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* [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec
@ 2011-07-15 12:59 michael.hennerich
  2011-07-15 12:59 ` [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System michael.hennerich
  2011-07-15 13:19 ` [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec Jonathan Cameron
  0 siblings, 2 replies; 13+ messages in thread
From: michael.hennerich @ 2011-07-15 12:59 UTC (permalink / raw)
  To: jic23; +Cc: linux-iio, device-drivers-devel, drivers, Michael Hennerich

From: Michael Hennerich <michael.hennerich@analog.com>

Allow dynamic allocation and population of channel spec.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
---
 drivers/staging/iio/iio.h |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
index 7a6ce4d..a9d7730 100644
--- a/drivers/staging/iio/iio.h
+++ b/drivers/staging/iio/iio.h
@@ -121,9 +121,9 @@ struct iio_chan_spec {
 		u8	storagebits;
 		u8	shift;
 	} scan_type;
-	const long		info_mask;
-	const long		event_mask;
-	const char		*extend_name;
+	long			info_mask;
+	long			event_mask;
+	char			*extend_name;
 	unsigned		processed_val:1;
 	unsigned		modified:1;
 	unsigned		indexed:1;
-- 
1.7.0.4

^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-15 12:59 [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec michael.hennerich
@ 2011-07-15 12:59 ` michael.hennerich
  2011-07-18 11:43   ` Jonathan Cameron
  2011-07-15 13:19 ` [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec Jonathan Cameron
  1 sibling, 1 reply; 13+ messages in thread
From: michael.hennerich @ 2011-07-15 12:59 UTC (permalink / raw)
  To: jic23; +Cc: linux-iio, device-drivers-devel, drivers, Michael Hennerich

From: Michael Hennerich <michael.hennerich@analog.com>


Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
---
 .../iio/Documentation/sysfs-bus-iio-adc-ad7280a    |   21 +
 drivers/staging/iio/adc/Kconfig                    |   10 +
 drivers/staging/iio/adc/Makefile                   |    1 +
 drivers/staging/iio/adc/ad7280a.c                  |  939 ++++++++++++++++++++
 drivers/staging/iio/adc/ad7280a.h                  |   38 +
 5 files changed, 1009 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
 create mode 100644 drivers/staging/iio/adc/ad7280a.c
 create mode 100644 drivers/staging/iio/adc/ad7280a.h

diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
new file mode 100644
index 0000000..fe90bd9
--- /dev/null
+++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
@@ -0,0 +1,21 @@
+What:		/sys/bus/iio/devices/deviceX/inY_balance_switch_en
+KernelVersion:	3.0.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Writing 1 enables the cell balance output switch corresponding
+		to input Y. Writing 0 disables it. If the inY_balance_timer is
+		set to a none zero value, the corresponding switch will enable
+		for the programmed amount of time, before it automatically
+		disables.
+
+What:		/sys/bus/iio/devices/deviceX/inY_balance_timer
+KernelVersion:	3.0.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		The inY_balance_timer file allows the user to program individual
+		times for each cell balance output. The AD7280A allows the user
+		to set the timer to a value from 0 minutes to 36.9 minutes.
+		The resolution of the timer is 71.5 sec. Corresponding to a
+		valid range of 0..31. When the timer value is set 0,
+		the timer is disabled. The cell balance outputs are controlled
+		only by inY_balance_switch_en.
diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index b39f2e1..60de7d7 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -182,6 +182,16 @@ config ADT7410
 	  Say yes here to build support for Analog Devices ADT7410
 	  temperature sensors.
 
+config AD7280
+	tristate "Analog Devices AD7280A Lithium Ion Battery Monitoring System"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices AD7280A
+	  Lithium Ion Battery Monitoring System.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad7280a
+
 config MAX1363
 	tristate "Maxim max1363 ADC driver"
 	depends on I2C
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index f020351..634a55f 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -40,3 +40,4 @@ obj-$(CONFIG_AD7816) += ad7816.o
 obj-$(CONFIG_ADT75) += adt75.o
 obj-$(CONFIG_ADT7310) += adt7310.o
 obj-$(CONFIG_ADT7410) += adt7410.o
+obj-$(CONFIG_AD7280) += ad7280a.o
diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
new file mode 100644
index 0000000..0efef55
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -0,0 +1,939 @@
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "adc.h"
+
+#include "ad7280a.h"
+
+/* Registers */
+#define AD7280A_CELL_VOLTAGE_1		0x0  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_2		0x1  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_3		0x2  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_4		0x3  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_5		0x4  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_6		0x5  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_1		0x6  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_2		0x7  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_3		0x8  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_4		0x9  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_5		0xA  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_6		0xB  /* D11 to D0, Read only */
+#define AD7280A_SELF_TEST		0xC  /* D11 to D0, Read only */
+#define AD7280A_CONTROL_HB		0xD  /* D15 to D8, Read/write */
+#define AD7280A_CONTROL_LB		0xE  /* D7 to D0, Read/write */
+#define AD7280A_CELL_OVERVOLTAGE	0xF  /* D7 to D0, Read/write */
+#define AD7280A_CELL_UNDERVOLTAGE	0x10 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_OVERVOLTAGE	0x11 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_UNDERVOLTAGE	0x12 /* D7 to D0, Read/write */
+#define AD7280A_ALERT			0x13 /* D7 to D0, Read/write */
+#define AD7280A_CELL_BALANCE		0x14 /* D7 to D0, Read/write */
+#define AD7280A_CB1_TIMER		0x15 /* D7 to D0, Read/write */
+#define AD7280A_CB2_TIMER		0x16 /* D7 to D0, Read/write */
+#define AD7280A_CB3_TIMER		0x17 /* D7 to D0, Read/write */
+#define AD7280A_CB4_TIMER		0x18 /* D7 to D0, Read/write */
+#define AD7280A_CB5_TIMER		0x19 /* D7 to D0, Read/write */
+#define AD7280A_CB6_TIMER		0x1A /* D7 to D0, Read/write */
+#define AD7280A_PD_TIMER		0x1B /* D7 to D0, Read/write */
+#define AD7280A_READ			0x1C /* D7 to D0, Read/write */
+#define AD7280A_CNVST_CONTROL		0x1D /* D7 to D0, Read/write */
+
+/* Bits and Masks */
+#define AD7280A_CTRL_HB_CONV_INPUT_ALL			(0 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4	(1 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL		(2 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST		(3 << 6)
+#define AD7280A_CTRL_HB_CONV_RES_READ_ALL		(0 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4	(1 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL		(2 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_NO		(3 << 4)
+#define AD7280A_CTRL_HB_CONV_START_CNVST		(0 << 3)
+#define AD7280A_CTRL_HB_CONV_START_CS			(1 << 3)
+#define AD7280A_CTRL_HB_CONV_AVG_DIS			(0 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_2			(1 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_4			(2 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_8			(3 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG(x)			((x) << 1)
+#define AD7280A_CTRL_HB_PWRDN_SW			(1 << 0)
+
+#define AD7280A_CTRL_LB_SWRST				(1 << 7)
+#define AD7280A_CTRL_LB_ACQ_TIME_400ns			(0 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_800ns			(1 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1200ns			(2 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1600ns			(3 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME(x)			((x) << 5)
+#define AD7280A_CTRL_LB_MUST_SET			(1 << 4)
+#define AD7280A_CTRL_LB_THERMISTOR_EN			(1 << 3)
+#define AD7280A_CTRL_LB_LOCK_DEV_ADDR			(1 << 2)
+#define AD7280A_CTRL_LB_INC_DEV_ADDR			(1 << 1)
+#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN		(1 << 0)
+
+#define AD7280A_ALERT_GEN_STATIC_HIGH			(1 << 6)
+#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN		(3 << 6)
+
+#define RES_MASK(bits)			((1 << (bits)) - 1)
+#define AD7280A_MAX_SPI_CLK_Hz		700000 /* < 1MHz */
+#define AD7280A_MAX_CHAIN		8
+#define AD7280A_CELLS_PER_DEV		6
+#define AD7280A_BITS			12
+#define AD7280A_NUM_CH			(AD7280A_AUX_ADC_6 - \
+					AD7280A_CELL_VOLTAGE_1 + 1)
+
+#define AD7280A_DEVADDR_MASTER		0
+#define AD7280A_DEVADDR_ALL		0x1F
+/* 5-bit device address is sent LSB first */
+#define AD7280A_DEVADDR(addr)	(((addr & 0x1) << 4) | ((addr & 0x2) << 3) | \
+				(addr & 0x4) | ((addr & 0x8) >> 3) | \
+				((addr & 0x10) >> 4))
+
+#define AD7280A_WRITE(DEVADDR, REGADDR, REGDATA, ADDRALL) \
+		      ((DEVADDR) << 27 | (REGADDR) << 21 | \
+		      ((REGDATA) & 0xFF) << 13 | ADDRALL << 12)
+
+#define AD7280A_APPEND_CRC(VAL, CRC) ((VAL) | (CRC) << 3 | 0x2)
+
+/*
+ * AD7280 CRC
+ *
+ * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F
+ */
+#define POLYNOM		0x2F
+#define POLYNOM_ORDER	8
+#define HIGHBIT		1 << (POLYNOM_ORDER - 1);
+
+struct ad7280_state {
+	struct spi_device		*spi;
+	struct iio_chan_spec		*channels;
+	struct iio_dev_attr		*iio_attr;
+	int				slave_num;
+	int				scan_cnt;
+	int				readback_delay_us;
+	unsigned char			crc_tab[256];
+	unsigned char			ctrl_hb;
+	unsigned char			ctrl_lb;
+	unsigned char			cell_threshhigh;
+	unsigned char			cell_threshlow;
+	unsigned char			aux_threshhigh;
+	unsigned char			aux_threshlow;
+	unsigned char			cb_mask[AD7280A_MAX_CHAIN];
+};
+
+static void ad7280_crc8_build_table(unsigned char *crc_tab)
+{
+	unsigned char bit, crc;
+	int cnt, i;
+
+	for (cnt = 0; cnt < 256; cnt++) {
+		crc = cnt;
+		for (i = 0; i < 8; i++) {
+			bit = crc & HIGHBIT;
+			crc <<= 1;
+			if (bit)
+				crc ^= POLYNOM;
+		}
+		crc_tab[cnt] = crc;
+	}
+}
+
+static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned val)
+{
+	unsigned char crc;
+
+	crc = crc_tab[val >> 16 & 0xFF];
+	crc = crc_tab[crc ^ (val >> 8 & 0xFF)];
+
+	return  crc ^ (val & 0xFF);
+}
+
+static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
+{
+	unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);
+
+	if (crc != ((val >> 2) & 0xFF))
+		return -EIO;
+
+	return 0;
+}
+
+static int __ad7280_write32(struct spi_device *spi, unsigned val)
+{
+	u32 data = cpu_to_be32(val);
+
+	return spi_write(spi, &data, 4);
+}
+
+static void ad7280_delay(struct ad7280_state *st)
+{
+	if (st->readback_delay_us < 50)
+		udelay(st->readback_delay_us);
+	else
+		msleep(1);
+}
+
+static int __ad7280_read32(struct spi_device *spi, unsigned *val)
+{
+	unsigned rx_buf, tx_buf = cpu_to_be32(0xF800030A);
+	int ret;
+
+	struct spi_transfer t = {
+		.tx_buf	= &tx_buf,
+		.rx_buf = &rx_buf,
+		.len = 4,
+	};
+	struct spi_message m;
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t, &m);
+
+	ret = spi_sync(spi, &m);
+	if (ret)
+		return ret;
+
+	*val = be32_to_cpu(rx_buf);
+
+	return 0;
+}
+
+static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
+			unsigned addr, bool all, unsigned val)
+{
+
+	unsigned reg = AD7280A_WRITE(devaddr, addr, val, all);
+
+	reg = AD7280A_APPEND_CRC(reg,
+		ad7280_calc_crc8(st->crc_tab, reg >> 11));
+
+	return __ad7280_write32(st->spi, reg);
+}
+
+static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
+			unsigned addr)
+{
+	int ret;
+	unsigned tmp;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_NO |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+	if (ret)
+		return ret;
+
+	__ad7280_read32(st->spi, &tmp);
+
+	if (ad7280_check_crc(st, tmp))
+		return -EIO;
+
+	if (((tmp >> 27) != devaddr) || (((tmp >> 21) & 0x3F) != addr))
+		return -EFAULT;
+
+	return (tmp >> 13) & 0xFF;
+}
+
+static int ad7280_read_channel(struct ad7280_state *st, unsigned devaddr,
+			       unsigned addr)
+{
+	int ret;
+	unsigned tmp;
+
+	ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_NO |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			AD7280A_CTRL_HB_CONV_START_CS |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ad7280_delay(st);
+
+	__ad7280_read32(st->spi, &tmp);
+
+	if (ad7280_check_crc(st, tmp))
+		return -EIO;
+
+	if (((tmp >> 27) != devaddr) || (((tmp >> 23) & 0xF) != addr))
+		return -EFAULT;
+
+	return (tmp >> 11) & 0xFFF;
+}
+
+static int ad7280_read_all_channels(struct ad7280_state *st, unsigned cnt,
+			     unsigned *array)
+{
+	int i, ret;
+	unsigned tmp, sum = 0;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+			   AD7280A_CELL_VOLTAGE_1 << 2);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			AD7280A_CTRL_HB_CONV_START_CS |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ad7280_delay(st);
+
+	for (i = 0; i < cnt; i++) {
+		__ad7280_read32(st->spi, &tmp);
+
+		if (ad7280_check_crc(st, tmp))
+			return -EIO;
+
+		if (array)
+			array[i] = tmp;
+		/* only sum cell voltages */
+		if (((tmp >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6)
+			sum += ((tmp >> 11) & 0xFFF);
+	}
+
+	return sum;
+}
+
+static int ad7280_chain_setup(struct ad7280_state *st)
+{
+	unsigned val, n;
+	int ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+			AD7280A_CTRL_LB_MUST_SET |
+			AD7280A_CTRL_LB_SWRST |
+			st->ctrl_lb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+			AD7280A_CTRL_LB_MUST_SET |
+			st->ctrl_lb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+			AD7280A_CONTROL_LB << 2);
+	if (ret)
+		return ret;
+
+	for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
+		__ad7280_read32(st->spi, &val);
+		if (val == 0)
+			return n - 1;
+
+		if (ad7280_check_crc(st, val))
+			return -EIO;
+
+		if (n != AD7280A_DEVADDR(val >> 27))
+			return -EIO;
+	}
+
+	return -EFAULT;
+}
+
+static ssize_t ad7280_show_balance_sw(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	return sprintf(buf, "%d\n",
+		       !!(st->cb_mask[this_attr->address >> 8] &
+		       (1 << ((this_attr->address & 0xFF) + 2))));
+}
+
+static ssize_t ad7280_store_balance_sw(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	bool readin;
+	int ret;
+	unsigned devaddr, ch;
+
+	ret = strtobool(buf, &readin);
+	if (ret)
+		return ret;
+
+	devaddr = this_attr->address >> 8;
+	ch = this_attr->address & 0xFF;
+
+	mutex_lock(&dev_info->mlock);
+	if (readin)
+		st->cb_mask[devaddr] |= 1 << (ch + 2);
+	else
+		st->cb_mask[devaddr] &= ~(1 << (ch + 2));
+
+	ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
+			   0, st->cb_mask[devaddr]);
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static ssize_t ad7280_show_balance_timer(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	int ret;
+
+	mutex_lock(&dev_info->mlock);
+	ret = ad7280_read(st, this_attr->address >> 8,
+			this_attr->address & 0xFF);
+	mutex_unlock(&dev_info->mlock);
+
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", ret >> 3);
+}
+
+static ssize_t ad7280_store_balance_timer(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	long val;
+	int ret;
+
+	ret = strict_strtol(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	mutex_lock(&dev_info->mlock);
+	ret = ad7280_write(st, this_attr->address >> 8,
+			   this_attr->address & 0xFF,
+			   0, (val & 0x1F) << 3);
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
+					   AD7280A_CELLS_PER_DEV * 2 + 1];
+
+static struct attribute_group ad7280_attrs_group = {
+	.attrs = ad7280_attributes,
+};
+
+static int ad7280_channel_init(struct ad7280_state *st)
+{
+	int dev, ch, cnt;
+
+	st->channels = kzalloc(sizeof(*st->channels) *
+				((st->slave_num + 1) * 12 + 2), GFP_KERNEL);
+	if (st->channels == NULL)
+		return -ENOMEM;
+
+	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_AUX_ADC_6; ch++,
+			cnt++) {
+			if (ch < AD7280A_AUX_ADC_1) {
+				st->channels[cnt].type = IIO_IN;
+				st->channels[cnt].channel = (dev * 6) + ch;
+			} else {
+				st->channels[cnt].type = IIO_TEMP;
+				st->channels[cnt].channel = (dev * 6) + ch - 6;
+			}
+			st->channels[cnt].indexed = 1;
+			st->channels[cnt].extend_name = NULL;
+			st->channels[cnt].info_mask =
+
+				(1 << IIO_CHAN_INFO_SCALE_SHARED);
+			st->channels[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 | ch;
+			st->channels[cnt].scan_index = cnt;
+			st->channels[cnt].scan_type.sign = 'u';
+			st->channels[cnt].scan_type.realbits = 12;
+			st->channels[cnt].scan_type.storagebits = 32;
+			st->channels[cnt].scan_type.shift = 0;
+		}
+
+	st->channels[cnt].type = IIO_IN_DIFF;
+	st->channels[cnt].channel = 0;
+	st->channels[cnt].channel2 = dev * 6 - 1;
+	st->channels[cnt].address = AD7280A_DEVADDR(dev) << 8 |
+		AD7280A_CELL_VOLTAGE_1;
+	st->channels[cnt].indexed = 1;
+	st->channels[cnt].extend_name = NULL;
+	st->channels[cnt].info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED);
+	st->channels[cnt].scan_index = cnt;
+	st->channels[cnt].scan_type.sign = 'u';
+	st->channels[cnt].scan_type.realbits = 32;
+	st->channels[cnt].scan_type.storagebits = 32;
+	st->channels[cnt].scan_type.shift = 0;
+	cnt++;
+	st->channels[cnt].type = IIO_TIMESTAMP;
+	st->channels[cnt].channel = -1;
+	st->channels[cnt].scan_index = cnt;
+	st->channels[cnt].scan_type.sign = 's';
+	st->channels[cnt].scan_type.realbits = 64;
+	st->channels[cnt].scan_type.storagebits = 64;
+	st->channels[cnt].scan_type.shift = 0;
+
+	return cnt + 1;
+}
+
+static int ad7280_attr_init(struct ad7280_state *st)
+{
+	int dev, ch, cnt;
+
+	st->iio_attr = kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1) *
+				AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
+	if (st->iio_attr == NULL)
+		return -ENOMEM;
+
+	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;
+			ch++, cnt++) {
+			st->iio_attr[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 | ch;
+			st->iio_attr[cnt].dev_attr.attr.mode =
+				S_IWUSR | S_IRUGO;
+			st->iio_attr[cnt].dev_attr.show =
+				ad7280_show_balance_sw;
+			st->iio_attr[cnt].dev_attr.store =
+				ad7280_store_balance_sw;
+			st->iio_attr[cnt].dev_attr.attr.name =
+				kasprintf(GFP_KERNEL, "in%d_balance_switch_en",
+					  (dev * AD7280A_CELLS_PER_DEV) + ch);
+			ad7280_attributes[cnt] =
+				&st->iio_attr[cnt].dev_attr.attr;
+			cnt++;
+			st->iio_attr[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 |
+				(AD7280A_CB1_TIMER + ch);
+			st->iio_attr[cnt].dev_attr.attr.mode =
+				S_IWUSR | S_IRUGO;
+			st->iio_attr[cnt].dev_attr.show =
+				ad7280_show_balance_timer;
+			st->iio_attr[cnt].dev_attr.store =
+				ad7280_store_balance_timer;
+			st->iio_attr[cnt].dev_attr.attr.name =
+				kasprintf(GFP_KERNEL, "in%d_balance_timer",
+					  (dev * AD7280A_CELLS_PER_DEV) + ch);
+			ad7280_attributes[cnt] =
+				&st->iio_attr[cnt].dev_attr.attr;
+		}
+
+	ad7280_attributes[cnt] = NULL;
+
+	return 0;
+}
+
+static ssize_t ad7280_read_channel_config(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	unsigned val;
+
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+		val = 1000 + (st->cell_threshhigh * 1568) / 100;
+		break;
+	case AD7280A_CELL_UNDERVOLTAGE:
+		val = 1000 + (st->cell_threshlow * 1568) / 100;
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+		val = (st->aux_threshhigh * 196) / 10;
+		break;
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		val = (st->aux_threshlow * 196) / 10;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t ad7280_write_channel_config(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	long val;
+	int ret;
+
+	ret = strict_strtol(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+	case AD7280A_CELL_UNDERVOLTAGE:
+		val = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		val = (val * 10) / 196; /* LSB 19.6mV */
+		break;
+	default:
+		return -EFAULT;
+	}
+
+	val = clamp(val, 0L, 0xFFL);
+
+	mutex_lock(&dev_info->mlock);
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+		st->cell_threshhigh = val;
+		break;
+	case AD7280A_CELL_UNDERVOLTAGE:
+		st->cell_threshlow = val;
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+		st->aux_threshhigh = val;
+		break;
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		st->aux_threshlow = val;
+		break;
+	}
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+			   this_attr->address, 1, val);
+
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static irqreturn_t ad7280_event_handler(int irq, void *private)
+{
+	struct iio_dev *dev_info = private;
+
+	iio_push_event(dev_info, 0,
+		       IIO_UNMOD_EVENT_CODE(IIO_IN,
+					    0,
+					    IIO_EV_TYPE_THRESH,
+					    IIO_EV_DIR_EITHER),
+		       iio_get_time_ns());
+
+	return IRQ_HANDLED;
+}
+
+static IIO_DEVICE_ATTR(in_thresh_low_value,
+		       S_IRUGO | S_IWUSR,
+		       ad7280_read_channel_config,
+		       ad7280_write_channel_config,
+		       AD7280A_CELL_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR(in_thresh_high_value,
+		       S_IRUGO | S_IWUSR,
+		       ad7280_read_channel_config,
+		       ad7280_write_channel_config,
+		       AD7280A_CELL_OVERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_low_value,
+		       S_IRUGO | S_IWUSR,
+		       ad7280_read_channel_config,
+		       ad7280_write_channel_config,
+		       AD7280A_AUX_ADC_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_high_value,
+		       S_IRUGO | S_IWUSR,
+		       ad7280_read_channel_config,
+		       ad7280_write_channel_config,
+		       AD7280A_AUX_ADC_OVERVOLTAGE);
+
+
+static struct attribute *ad7280_event_attributes[] = {
+	&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
+	&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
+	&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
+	&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
+	NULL,
+};
+
+static struct attribute_group ad7280_event_attrs_group = {
+	.attrs = ad7280_event_attributes,
+};
+
+static int ad7280_read_raw(struct iio_dev *dev_info,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad7280_state *st = iio_priv(dev_info);
+	unsigned int scale_uv;
+	int ret;
+
+	switch (m) {
+	case 0:
+		mutex_lock(&dev_info->mlock);
+		switch (chan->type) {
+		case IIO_IN:
+			ret = ad7280_read_channel(st, chan->address >> 8,
+						  chan->address & 0xFF);
+			break;
+		case IIO_IN_DIFF:
+			ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
+			break;
+		default:
+			ret = -EINVAL;
+		}
+		mutex_unlock(&dev_info->mlock);
+
+		if (ret < 0)
+			return ret;
+
+		*val = ret;
+
+		return IIO_VAL_INT;
+	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+		if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6)
+			scale_uv = (4000 * 1000) >> AD7280A_BITS;
+		else
+			scale_uv = (5000 * 1000) >> AD7280A_BITS;
+
+		*val =  scale_uv / 1000;
+		*val2 = (scale_uv % 1000) * 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+	return -EINVAL;
+}
+
+static const struct iio_info ad7280_info = {
+	.read_raw = &ad7280_read_raw,
+	.num_interrupt_lines = 1,
+	.event_attrs = &ad7280_event_attrs_group,
+	.attrs = &ad7280_attrs_group,
+	.driver_module = THIS_MODULE,
+};
+
+static struct ad7280_platform_data ad7793_default_pdata = {
+	.acquisition_time = AD7280A_ACQ_TIME_400ns,
+	.conversion_averaging = AD7280A_CONV_AVG_DIS,
+	.thermistor_term_en = true,
+};
+
+static int __devinit ad7280_probe(struct spi_device *spi)
+{
+	struct ad7280_platform_data *pdata = spi->dev.platform_data;
+	struct ad7280_state *st;
+	int ret, regdone = 0;
+	const unsigned short tACQ_ns[4] = {465, 1010, 1460, 1890};
+	const unsigned short nAVG[4] = {1, 2, 4, 8};
+	struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
+
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	spi_set_drvdata(spi, indio_dev);
+	st->spi = spi;
+
+	if (!pdata)
+		pdata = &ad7793_default_pdata;
+
+	ad7280_crc8_build_table(st->crc_tab);
+
+	st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_Hz;
+	st->spi->mode = SPI_MODE_1;
+	spi_setup(st->spi);
+
+	st->ctrl_lb = AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & 0x3);
+	st->ctrl_hb = AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averaging
+			& 0x3) | (pdata->thermistor_term_en ?
+			AD7280A_CTRL_LB_THERMISTOR_EN : 0);
+
+	ret = ad7280_chain_setup(st);
+	if (ret < 0)
+		goto error_free_device;
+
+	st->slave_num = ret;
+	st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
+	st->cell_threshhigh = 0xFF;
+	st->aux_threshhigh = 0xFF;
+
+	/*
+	 * Total Conversion Time = ((tACQ + tCONV) *
+	 *			   (Number of Conversions per Part)) −
+	 *			   tACQ + ((N - 1) * tDELAY)
+	 *
+	 * Readback Delay = Total Conversion Time + tWAIT
+	 */
+
+	st->readback_delay_us =
+		((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
+		(AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
+		- tACQ_ns[pdata->acquisition_time & 0x3] +
+		st->slave_num * 250;
+
+	/* Convert to usecs */
+	st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);
+	st->readback_delay_us += 5; /* Add tWAIT */
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = ad7280_channel_init(st);
+	if (ret < 0)
+		goto error_free_device;
+
+	indio_dev->num_channels = ret;
+	indio_dev->channels = st->channels;
+	indio_dev->info = &ad7280_info;
+
+	ret = ad7280_attr_init(st);
+	if (ret < 0)
+		goto error_free_channels;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_free_attr;
+	regdone = 1;
+
+	if (spi->irq > 0) {
+		ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+				   AD7280A_ALERT, 1,
+				   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
+		if (ret)
+			goto error_free_attr;
+
+		ret = ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
+				   AD7280A_ALERT, 0,
+				   AD7280A_ALERT_GEN_STATIC_HIGH |
+				   (pdata->chain_last_alert_ignore & 0xF));
+		if (ret)
+			goto error_free_attr;
+
+		ret = request_threaded_irq(spi->irq,
+					   NULL,
+					   ad7280_event_handler,
+					   IRQF_TRIGGER_FALLING |
+					   IRQF_ONESHOT,
+					   indio_dev->name,
+					   indio_dev);
+		if (ret)
+			goto error_free_attr;
+	}
+
+	return 0;
+
+error_free_attr:
+	kfree(st->iio_attr);
+
+error_free_channels:
+	kfree(st->channels);
+
+error_free_device:
+	if (regdone)
+		iio_device_unregister(indio_dev);
+	else
+		iio_free_device(indio_dev);
+
+	return ret;
+}
+
+static int __devexit ad7280_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ad7280_state *st = iio_priv(indio_dev);
+
+	if (spi->irq > 0)
+		free_irq(spi->irq, indio_dev);
+
+	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
+
+	kfree(st->channels);
+	kfree(st->iio_attr);
+	iio_device_unregister(indio_dev);
+
+	return 0;
+}
+
+static const struct spi_device_id ad7280_id[] = {
+	{"ad7280a", 0},
+	{}
+};
+
+static struct spi_driver ad7280_driver = {
+	.driver = {
+		.name	= "ad7280",
+		.bus	= &spi_bus_type,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ad7280_probe,
+	.remove		= __devexit_p(ad7280_remove),
+	.id_table	= ad7280_id,
+};
+
+static int __init ad7280_init(void)
+{
+	return spi_register_driver(&ad7280_driver);
+}
+module_init(ad7280_init);
+
+static void __exit ad7280_exit(void)
+{
+	spi_unregister_driver(&ad7280_driver);
+}
+module_exit(ad7280_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7280A");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/iio/adc/ad7280a.h b/drivers/staging/iio/adc/ad7280a.h
new file mode 100644
index 0000000..20400b0
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7280a.h
@@ -0,0 +1,38 @@
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_ADC_AD7280_H_
+#define IIO_ADC_AD7280_H_
+
+/*
+ * TODO: struct ad7280_platform_data needs to go into include/linux/iio
+ */
+
+#define AD7280A_ACQ_TIME_400ns			0
+#define AD7280A_ACQ_TIME_800ns			1
+#define AD7280A_ACQ_TIME_1200ns			2
+#define AD7280A_ACQ_TIME_1600ns			3
+
+#define AD7280A_CONV_AVG_DIS			0
+#define AD7280A_CONV_AVG_2			1
+#define AD7280A_CONV_AVG_4			2
+#define AD7280A_CONV_AVG_8			3
+
+#define AD7280A_ALERT_REMOVE_VIN5		(1 << 2)
+#define AD7280A_ALERT_REMOVE_VIN4_VIN5		(2 << 2)
+#define AD7280A_ALERT_REMOVE_AUX5		(1 << 0)
+#define AD7280A_ALERT_REMOVE_AUX4_AUX5		(2 << 0)
+
+struct ad7280_platform_data {
+	unsigned acquisition_time;
+	unsigned conversion_averaging;
+	unsigned chain_last_alert_ignore;
+	bool thermistor_term_en;
+};
+
+#endif /* IIO_ADC_AD7280_H_ */
-- 
1.7.0.4



^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec
  2011-07-15 12:59 [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec michael.hennerich
  2011-07-15 12:59 ` [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System michael.hennerich
@ 2011-07-15 13:19 ` Jonathan Cameron
  1 sibling, 0 replies; 13+ messages in thread
From: Jonathan Cameron @ 2011-07-15 13:19 UTC (permalink / raw)
  To: michael.hennerich; +Cc: linux-iio, device-drivers-devel, drivers

On 07/15/11 13:59, michael.hennerich@analog.com wrote:
> From: Michael Hennerich <michael.hennerich@analog.com>
> 
> Allow dynamic allocation and population of channel spec.
> 
> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
> ---
>  drivers/staging/iio/iio.h |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
> index 7a6ce4d..a9d7730 100644
> --- a/drivers/staging/iio/iio.h
> +++ b/drivers/staging/iio/iio.h
> @@ -121,9 +121,9 @@ struct iio_chan_spec {
>  		u8	storagebits;
>  		u8	shift;
>  	} scan_type;
> -	const long		info_mask;
> -	const long		event_mask;
> -	const char		*extend_name;
> +	long			info_mask;
> +	long			event_mask;
> +	char			*extend_name;
>  	unsigned		processed_val:1;
>  	unsigned		modified:1;
>  	unsigned		indexed:1;


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-15 12:59 ` [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System michael.hennerich
@ 2011-07-18 11:43   ` Jonathan Cameron
  2011-07-18 12:48     ` Michael Hennerich
  0 siblings, 1 reply; 13+ messages in thread
From: Jonathan Cameron @ 2011-07-18 11:43 UTC (permalink / raw)
  To: michael.hennerich; +Cc: linux-iio, device-drivers-devel, drivers

On 07/15/11 13:59, michael.hennerich@analog.com wrote:
> From: Michael Hennerich <michael.hennerich@analog.com>

Hi Michael, although anyone reading the datasheets will quickly
discover that this isn't a simple laptop style battery monitor,
it's probably worth making that clear in the patch title or
at very least here.

Driver is pretty clear. Couple of nitpicks / queries inline.

Thanks

Jonathan
>=20
>=20
> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
> ---
>  .../iio/Documentation/sysfs-bus-iio-adc-ad7280a    |   21 +
>  drivers/staging/iio/adc/Kconfig                    |   10 +
>  drivers/staging/iio/adc/Makefile                   |    1 +
>  drivers/staging/iio/adc/ad7280a.c                  |  939 ++++++++++=
++++++++++
>  drivers/staging/iio/adc/ad7280a.h                  |   38 +
>  5 files changed, 1009 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/staging/iio/Documentation/sysfs-bus-iio-a=
dc-ad7280a
>  create mode 100644 drivers/staging/iio/adc/ad7280a.c
>  create mode 100644 drivers/staging/iio/adc/ad7280a.h
>=20
> diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad72=
80a b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
> new file mode 100644
> index 0000000..fe90bd9
> --- /dev/null
> +++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
> @@ -0,0 +1,21 @@
> +What:		/sys/bus/iio/devices/deviceX/inY_balance_switch_en
> +KernelVersion:	3.0.0
> +Contact:	linux-iio@vger.kernel.org
> +Description:
> +		Writing 1 enables the cell balance output switch corresponding
> +		to input Y. Writing 0 disables it. If the inY_balance_timer is
> +		set to a none zero value, the corresponding switch will enable
> +		for the programmed amount of time, before it automatically
> +		disables.
> +
> +What:		/sys/bus/iio/devices/deviceX/inY_balance_timer
> +KernelVersion:	3.0.0
> +Contact:	linux-iio@vger.kernel.org
> +Description:
> +		The inY_balance_timer file allows the user to program individual
> +		times for each cell balance output. The AD7280A allows the user
> +		to set the timer to a value from 0 minutes to 36.9 minutes.
> +		The resolution of the timer is 71.5 sec. Corresponding to a
> +		valid range of 0..31. When the timer value is set 0,
> +		the timer is disabled. The cell balance outputs are controlled
> +		only by inY_balance_switch_en.
I'd prefer to see that in SI units and do the conversion to the interna=
l units
in the driver.

> diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/ad=
c/Kconfig
> index b39f2e1..60de7d7 100644
> --- a/drivers/staging/iio/adc/Kconfig
> +++ b/drivers/staging/iio/adc/Kconfig
> @@ -182,6 +182,16 @@ config ADT7410
>  	  Say yes here to build support for Analog Devices ADT7410
>  	  temperature sensors.
> =20
> +config AD7280
> +	tristate "Analog Devices AD7280A Lithium Ion Battery Monitoring Sys=
tem"
> +	depends on SPI
> +	help
> +	  Say yes here to build support for Analog Devices AD7280A
> +	  Lithium Ion Battery Monitoring System.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called ad7280a
> +
>  config MAX1363
>  	tristate "Maxim max1363 ADC driver"
>  	depends on I2C
> diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/a=
dc/Makefile
> index f020351..634a55f 100644
> --- a/drivers/staging/iio/adc/Makefile
> +++ b/drivers/staging/iio/adc/Makefile
> @@ -40,3 +40,4 @@ obj-$(CONFIG_AD7816) +=3D ad7816.o
>  obj-$(CONFIG_ADT75) +=3D adt75.o
>  obj-$(CONFIG_ADT7310) +=3D adt7310.o
>  obj-$(CONFIG_ADT7410) +=3D adt7410.o
> +obj-$(CONFIG_AD7280) +=3D ad7280a.o
> diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/=
adc/ad7280a.c
> new file mode 100644
> index 0000000..0efef55
> --- /dev/null
> +++ b/drivers/staging/iio/adc/ad7280a.c
> @@ -0,0 +1,939 @@
> +/*
> + * AD7280A Lithium Ion Battery Monitoring System
> + *
> + * Copyright 2011 Analog Devices Inc.
> + *
> + * Licensed under the GPL-2.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/sysfs.h>
> +#include <linux/spi/spi.h>
> +#include <linux/err.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +
> +#include "../iio.h"
> +#include "../sysfs.h"
> +#include "adc.h"
> +
> +#include "ad7280a.h"
> +
> +/* Registers */
> +#define AD7280A_CELL_VOLTAGE_1		0x0  /* D11 to D0, Read only */
> +#define AD7280A_CELL_VOLTAGE_2		0x1  /* D11 to D0, Read only */
> +#define AD7280A_CELL_VOLTAGE_3		0x2  /* D11 to D0, Read only */
> +#define AD7280A_CELL_VOLTAGE_4		0x3  /* D11 to D0, Read only */
> +#define AD7280A_CELL_VOLTAGE_5		0x4  /* D11 to D0, Read only */
> +#define AD7280A_CELL_VOLTAGE_6		0x5  /* D11 to D0, Read only */
> +#define AD7280A_AUX_ADC_1		0x6  /* D11 to D0, Read only */
> +#define AD7280A_AUX_ADC_2		0x7  /* D11 to D0, Read only */
> +#define AD7280A_AUX_ADC_3		0x8  /* D11 to D0, Read only */
> +#define AD7280A_AUX_ADC_4		0x9  /* D11 to D0, Read only */
> +#define AD7280A_AUX_ADC_5		0xA  /* D11 to D0, Read only */
> +#define AD7280A_AUX_ADC_6		0xB  /* D11 to D0, Read only */
> +#define AD7280A_SELF_TEST		0xC  /* D11 to D0, Read only */
> +#define AD7280A_CONTROL_HB		0xD  /* D15 to D8, Read/write */
> +#define AD7280A_CONTROL_LB		0xE  /* D7 to D0, Read/write */
> +#define AD7280A_CELL_OVERVOLTAGE	0xF  /* D7 to D0, Read/write */
> +#define AD7280A_CELL_UNDERVOLTAGE	0x10 /* D7 to D0, Read/write */
> +#define AD7280A_AUX_ADC_OVERVOLTAGE	0x11 /* D7 to D0, Read/write */
> +#define AD7280A_AUX_ADC_UNDERVOLTAGE	0x12 /* D7 to D0, Read/write */
> +#define AD7280A_ALERT			0x13 /* D7 to D0, Read/write */
> +#define AD7280A_CELL_BALANCE		0x14 /* D7 to D0, Read/write */
> +#define AD7280A_CB1_TIMER		0x15 /* D7 to D0, Read/write */
> +#define AD7280A_CB2_TIMER		0x16 /* D7 to D0, Read/write */
> +#define AD7280A_CB3_TIMER		0x17 /* D7 to D0, Read/write */
> +#define AD7280A_CB4_TIMER		0x18 /* D7 to D0, Read/write */
> +#define AD7280A_CB5_TIMER		0x19 /* D7 to D0, Read/write */
> +#define AD7280A_CB6_TIMER		0x1A /* D7 to D0, Read/write */
> +#define AD7280A_PD_TIMER		0x1B /* D7 to D0, Read/write */
> +#define AD7280A_READ			0x1C /* D7 to D0, Read/write */
> +#define AD7280A_CNVST_CONTROL		0x1D /* D7 to D0, Read/write */
> +
> +/* Bits and Masks */
> +#define AD7280A_CTRL_HB_CONV_INPUT_ALL			(0 << 6)
> +#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4	(1 << 6)
> +#define AD7280A_CTRL_HB_CONV_INPUT_6CELL		(2 << 6)
> +#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST		(3 << 6)
> +#define AD7280A_CTRL_HB_CONV_RES_READ_ALL		(0 << 4)
> +#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4	(1 << 4)
> +#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL		(2 << 4)
> +#define AD7280A_CTRL_HB_CONV_RES_READ_NO		(3 << 4)
> +#define AD7280A_CTRL_HB_CONV_START_CNVST		(0 << 3)
> +#define AD7280A_CTRL_HB_CONV_START_CS			(1 << 3)
> +#define AD7280A_CTRL_HB_CONV_AVG_DIS			(0 << 1)
> +#define AD7280A_CTRL_HB_CONV_AVG_2			(1 << 1)
> +#define AD7280A_CTRL_HB_CONV_AVG_4			(2 << 1)
> +#define AD7280A_CTRL_HB_CONV_AVG_8			(3 << 1)
> +#define AD7280A_CTRL_HB_CONV_AVG(x)			((x) << 1)
> +#define AD7280A_CTRL_HB_PWRDN_SW			(1 << 0)
> +
> +#define AD7280A_CTRL_LB_SWRST				(1 << 7)
> +#define AD7280A_CTRL_LB_ACQ_TIME_400ns			(0 << 5)
> +#define AD7280A_CTRL_LB_ACQ_TIME_800ns			(1 << 5)
> +#define AD7280A_CTRL_LB_ACQ_TIME_1200ns			(2 << 5)
> +#define AD7280A_CTRL_LB_ACQ_TIME_1600ns			(3 << 5)
> +#define AD7280A_CTRL_LB_ACQ_TIME(x)			((x) << 5)
> +#define AD7280A_CTRL_LB_MUST_SET			(1 << 4)
> +#define AD7280A_CTRL_LB_THERMISTOR_EN			(1 << 3)
> +#define AD7280A_CTRL_LB_LOCK_DEV_ADDR			(1 << 2)
> +#define AD7280A_CTRL_LB_INC_DEV_ADDR			(1 << 1)
> +#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN		(1 << 0)
> +
> +#define AD7280A_ALERT_GEN_STATIC_HIGH			(1 << 6)
> +#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN		(3 << 6)
> +
> +#define RES_MASK(bits)			((1 << (bits)) - 1)
> +#define AD7280A_MAX_SPI_CLK_Hz		700000 /* < 1MHz */
> +#define AD7280A_MAX_CHAIN		8
> +#define AD7280A_CELLS_PER_DEV		6
> +#define AD7280A_BITS			12
> +#define AD7280A_NUM_CH			(AD7280A_AUX_ADC_6 - \
> +					AD7280A_CELL_VOLTAGE_1 + 1)
> +
> +#define AD7280A_DEVADDR_MASTER		0
> +#define AD7280A_DEVADDR_ALL		0x1F
> +/* 5-bit device address is sent LSB first */
> +#define AD7280A_DEVADDR(addr)	(((addr & 0x1) << 4) | ((addr & 0x2) <=
< 3) | \
> +				(addr & 0x4) | ((addr & 0x8) >> 3) | \
> +				((addr & 0x10) >> 4))
> +
Probably squish this into the one user for clarity.

> +#define AD7280A_WRITE(DEVADDR, REGADDR, REGDATA, ADDRALL) \
> +		      ((DEVADDR) << 27 | (REGADDR) << 21 | \
> +		      ((REGDATA) & 0xFF) << 13 | ADDRALL << 12)
> +
Same with this one.
> +#define AD7280A_APPEND_CRC(VAL, CRC) ((VAL) | (CRC) << 3 | 0x2)
> +
> +/*
> + * AD7280 CRC
> + *
> + * P(x) =3D x^8 + x^5 + x^3 + x^2 + x^1 + x^0 =3D 0b100101111 =3D> 0=
x2F
> + */
> +#define POLYNOM		0x2F
> +#define POLYNOM_ORDER	8
> +#define HIGHBIT		1 << (POLYNOM_ORDER - 1);
> +
> +struct ad7280_state {
> +	struct spi_device		*spi;
> +	struct iio_chan_spec		*channels;
> +	struct iio_dev_attr		*iio_attr;
> +	int				slave_num;
> +	int				scan_cnt;
> +	int				readback_delay_us;
> +	unsigned char			crc_tab[256];
> +	unsigned char			ctrl_hb;
> +	unsigned char			ctrl_lb;
> +	unsigned char			cell_threshhigh;
> +	unsigned char			cell_threshlow;
> +	unsigned char			aux_threshhigh;
> +	unsigned char			aux_threshlow;
> +	unsigned char			cb_mask[AD7280A_MAX_CHAIN];
> +};
> +
> +static void ad7280_crc8_build_table(unsigned char *crc_tab)
> +{
> +	unsigned char bit, crc;
> +	int cnt, i;
> +
> +	for (cnt =3D 0; cnt < 256; cnt++) {
> +		crc =3D cnt;
> +		for (i =3D 0; i < 8; i++) {
> +			bit =3D crc & HIGHBIT;
> +			crc <<=3D 1;
> +			if (bit)
> +				crc ^=3D POLYNOM;
> +		}
> +		crc_tab[cnt] =3D crc;
> +	}
> +}
> +
> +static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsign=
ed val)
> +{
> +	unsigned char crc;
> +
> +	crc =3D crc_tab[val >> 16 & 0xFF];
> +	crc =3D crc_tab[crc ^ (val >> 8 & 0xFF)];
> +
> +	return  crc ^ (val & 0xFF);
> +}
> +
> +static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
> +{
> +	unsigned char crc =3D ad7280_calc_crc8(st->crc_tab, val >> 10);
> +
> +	if (crc !=3D ((val >> 2) & 0xFF))
> +		return -EIO;
> +
> +	return 0;
> +}
> +
Any real reason for this tiny wrapper?  I'd squash into the call
site given there is only one of them.
> +static int __ad7280_write32(struct spi_device *spi, unsigned val)
> +{
> +	u32 data =3D cpu_to_be32(val);
> +
> +	return spi_write(spi, &data, 4);
> +}
> +
This needs an explanatory comment.
> +static void ad7280_delay(struct ad7280_state *st)
> +{
> +	if (st->readback_delay_us < 50)
> +		udelay(st->readback_delay_us);
> +	else
> +		msleep(1);
> +}
> +
> +static int __ad7280_read32(struct spi_device *spi, unsigned *val)
> +{
Please explain the magic constant.

> +	unsigned rx_buf, tx_buf =3D cpu_to_be32(0xF800030A);
> +	int ret;
> +
> +	struct spi_transfer t =3D {
> +		.tx_buf	=3D &tx_buf,
> +		.rx_buf =3D &rx_buf,
> +		.len =3D 4,
> +	};
> +	struct spi_message m;
> +
> +	spi_message_init(&m);
> +	spi_message_add_tail(&t, &m);
> +
> +	ret =3D spi_sync(spi, &m);
> +	if (ret)
> +		return ret;
> +
> +	*val =3D be32_to_cpu(rx_buf);
> +
> +	return 0;
> +}
> +
> +static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
> +			unsigned addr, bool all, unsigned val)
> +{
> +
> +	unsigned reg =3D AD7280A_WRITE(devaddr, addr, val, all);
> +
> +	reg =3D AD7280A_APPEND_CRC(reg,
> +		ad7280_calc_crc8(st->crc_tab, reg >> 11));
> +
> +	return __ad7280_write32(st->spi, reg);
> +}
> +
> +static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
> +			unsigned addr)
> +{
> +	int ret;
> +	unsigned tmp;
This would benefit form a few explanatory comments.
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB=
, 1,
> +			AD7280A_CTRL_HB_CONV_INPUT_ALL |
> +			AD7280A_CTRL_HB_CONV_RES_READ_NO |
> +			st->ctrl_hb);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
> +			AD7280A_CTRL_HB_CONV_INPUT_ALL |
> +			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
> +			st->ctrl_hb);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
> +	if (ret)
> +		return ret;
> +
> +	__ad7280_read32(st->spi, &tmp);
> +
> +	if (ad7280_check_crc(st, tmp))
> +		return -EIO;
> +
> +	if (((tmp >> 27) !=3D devaddr) || (((tmp >> 21) & 0x3F) !=3D addr))
> +		return -EFAULT;
> +
> +	return (tmp >> 13) & 0xFF;
> +}
> +
> +static int ad7280_read_channel(struct ad7280_state *st, unsigned dev=
addr,
> +			       unsigned addr)
> +{
> +	int ret;
> +	unsigned tmp;
> +
> +	ret =3D ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB=
, 1,
> +			AD7280A_CTRL_HB_CONV_INPUT_ALL |
> +			AD7280A_CTRL_HB_CONV_RES_READ_NO |
> +			st->ctrl_hb);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
> +			AD7280A_CTRL_HB_CONV_INPUT_ALL |
> +			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
> +			AD7280A_CTRL_HB_CONV_START_CS |
> +			st->ctrl_hb);
> +	if (ret)
> +		return ret;
> +
> +	ad7280_delay(st);
> +
> +	__ad7280_read32(st->spi, &tmp);
> +
> +	if (ad7280_check_crc(st, tmp))
> +		return -EIO;
> +
> +	if (((tmp >> 27) !=3D devaddr) || (((tmp >> 23) & 0xF) !=3D addr))
> +		return -EFAULT;
> +
> +	return (tmp >> 11) & 0xFFF;
> +}
> +
> +static int ad7280_read_all_channels(struct ad7280_state *st, unsigne=
d cnt,
> +			     unsigned *array)
> +{
> +	int i, ret;
> +	unsigned tmp, sum =3D 0;
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
> +			   AD7280A_CELL_VOLTAGE_1 << 2);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB=
, 1,
> +			AD7280A_CTRL_HB_CONV_INPUT_ALL |
> +			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
> +			AD7280A_CTRL_HB_CONV_START_CS |
> +			st->ctrl_hb);
> +	if (ret)
> +		return ret;
> +
> +	ad7280_delay(st);
> +
> +	for (i =3D 0; i < cnt; i++) {
> +		__ad7280_read32(st->spi, &tmp);
> +
> +		if (ad7280_check_crc(st, tmp))
> +			return -EIO;
> +
> +		if (array)
> +			array[i] =3D tmp;
> +		/* only sum cell voltages */
> +		if (((tmp >> 23) & 0xF) <=3D AD7280A_CELL_VOLTAGE_6)
> +			sum +=3D ((tmp >> 11) & 0xFFF);
> +	}
> +
> +	return sum;
> +}
> +
> +static int ad7280_chain_setup(struct ad7280_state *st)
> +{
> +	unsigned val, n;
> +	int ret;
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB=
, 1,
> +			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
> +			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
> +			AD7280A_CTRL_LB_MUST_SET |
> +			AD7280A_CTRL_LB_SWRST |
> +			st->ctrl_lb);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB=
, 1,
> +			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
> +			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
> +			AD7280A_CTRL_LB_MUST_SET |
> +			st->ctrl_lb);
> +	if (ret)
> +		return ret;
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
> +			AD7280A_CONTROL_LB << 2);
> +	if (ret)
> +		return ret;
> +
> +	for (n =3D 0; n <=3D AD7280A_MAX_CHAIN; n++) {
> +		__ad7280_read32(st->spi, &val);
> +		if (val =3D=3D 0)
> +			return n - 1;
> +
> +		if (ad7280_check_crc(st, val))
> +			return -EIO;
> +
> +		if (n !=3D AD7280A_DEVADDR(val >> 27))
> +			return -EIO;
> +	}
> +
> +	return -EFAULT;
> +}
> +
> +static ssize_t ad7280_show_balance_sw(struct device *dev,
> +					struct device_attribute *attr,
> +					char *buf)
> +{
> +	struct iio_dev *dev_info =3D dev_get_drvdata(dev);
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
> +
> +	return sprintf(buf, "%d\n",
> +		       !!(st->cb_mask[this_attr->address >> 8] &
> +		       (1 << ((this_attr->address & 0xFF) + 2))));
> +}
> +
> +static ssize_t ad7280_store_balance_sw(struct device *dev,
> +					 struct device_attribute *attr,
> +					 const char *buf,
> +					 size_t len)
> +{
> +	struct iio_dev *dev_info =3D dev_get_drvdata(dev);
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
> +	bool readin;
> +	int ret;
> +	unsigned devaddr, ch;
> +
> +	ret =3D strtobool(buf, &readin);
> +	if (ret)
> +		return ret;
> +
> +	devaddr =3D this_attr->address >> 8;
> +	ch =3D this_attr->address & 0xFF;
> +
> +	mutex_lock(&dev_info->mlock);
> +	if (readin)
> +		st->cb_mask[devaddr] |=3D 1 << (ch + 2);
> +	else
> +		st->cb_mask[devaddr] &=3D ~(1 << (ch + 2));
> +
> +	ret =3D ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
> +			   0, st->cb_mask[devaddr]);
> +	mutex_unlock(&dev_info->mlock);
> +
> +	return ret ? ret : len;
> +}
> +
> +static ssize_t ad7280_show_balance_timer(struct device *dev,
> +					struct device_attribute *attr,
> +					char *buf)
> +{
> +	struct iio_dev *dev_info =3D dev_get_drvdata(dev);
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
> +	int ret;
> +
> +	mutex_lock(&dev_info->mlock);
> +	ret =3D ad7280_read(st, this_attr->address >> 8,
> +			this_attr->address & 0xFF);
> +	mutex_unlock(&dev_info->mlock);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%d\n", ret >> 3);
> +}
> +
> +static ssize_t ad7280_store_balance_timer(struct device *dev,
> +					 struct device_attribute *attr,
> +					 const char *buf,
> +					 size_t len)
> +{
> +	struct iio_dev *dev_info =3D dev_get_drvdata(dev);
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
> +	long val;
> +	int ret;
> +
> +	ret =3D strict_strtol(buf, 10, &val);
> +	if (ret)
> +		return ret;
> +
> +	mutex_lock(&dev_info->mlock);
> +	ret =3D ad7280_write(st, this_attr->address >> 8,
> +			   this_attr->address & 0xFF,
> +			   0, (val & 0x1F) << 3);
> +	mutex_unlock(&dev_info->mlock);
> +
> +	return ret ? ret : len;
> +}
> +
> +static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
> +					   AD7280A_CELLS_PER_DEV * 2 + 1];
> +
> +static struct attribute_group ad7280_attrs_group =3D {
> +	.attrs =3D ad7280_attributes,
> +};
> +
> +static int ad7280_channel_init(struct ad7280_state *st)
> +{
> +	int dev, ch, cnt;
> +
> +	st->channels =3D kzalloc(sizeof(*st->channels) *
> +				((st->slave_num + 1) * 12 + 2), GFP_KERNEL);
> +	if (st->channels =3D=3D NULL)
> +		return -ENOMEM;
> +
> +	for (dev =3D 0, cnt =3D 0; dev <=3D st->slave_num; dev++)
> +		for (ch =3D AD7280A_CELL_VOLTAGE_1; ch <=3D AD7280A_AUX_ADC_6; ch+=
+,
> +			cnt++) {
> +			if (ch < AD7280A_AUX_ADC_1) {
> +				st->channels[cnt].type =3D IIO_IN;
> +				st->channels[cnt].channel =3D (dev * 6) + ch;
> +			} else {
> +				st->channels[cnt].type =3D IIO_TEMP;
> +				st->channels[cnt].channel =3D (dev * 6) + ch - 6;
> +			}
> +			st->channels[cnt].indexed =3D 1;
> +			st->channels[cnt].extend_name =3D NULL;
Don't bother setting it then. You kzalloc'd the array.

> +			st->channels[cnt].info_mask =3D
> +
> +				(1 << IIO_CHAN_INFO_SCALE_SHARED);
Something strange in spacing above.
> +			st->channels[cnt].address =3D
> +				AD7280A_DEVADDR(dev) << 8 | ch;
> +			st->channels[cnt].scan_index =3D cnt;
> +			st->channels[cnt].scan_type.sign =3D 'u';
> +			st->channels[cnt].scan_type.realbits =3D 12;
> +			st->channels[cnt].scan_type.storagebits =3D 32;
> +			st->channels[cnt].scan_type.shift =3D 0;
> +		}
> +
I'm a little confused here. So we have 6 voltage and 6 temp channels fr=
om
each part in the chain. What is this last one?
> +	st->channels[cnt].type =3D IIO_IN_DIFF;
> +	st->channels[cnt].channel =3D 0;
> +	st->channels[cnt].channel2 =3D dev * 6 - 1;
> +	st->channels[cnt].address =3D AD7280A_DEVADDR(dev) << 8 |
> +		AD7280A_CELL_VOLTAGE_1;
> +	st->channels[cnt].indexed =3D 1;
Don't bother setting to NULL.
> +	st->channels[cnt].extend_name =3D NULL;
> +	st->channels[cnt].info_mask =3D (1 << IIO_CHAN_INFO_SCALE_SHARED);
> +	st->channels[cnt].scan_index =3D cnt;
> +	st->channels[cnt].scan_type.sign =3D 'u';
> +	st->channels[cnt].scan_type.realbits =3D 32;
> +	st->channels[cnt].scan_type.storagebits =3D 32;
> +	st->channels[cnt].scan_type.shift =3D 0;
> +	cnt++;
> +	st->channels[cnt].type =3D IIO_TIMESTAMP;
> +	st->channels[cnt].channel =3D -1;
> +	st->channels[cnt].scan_index =3D cnt;
> +	st->channels[cnt].scan_type.sign =3D 's';
> +	st->channels[cnt].scan_type.realbits =3D 64;
> +	st->channels[cnt].scan_type.storagebits =3D 64;
> +	st->channels[cnt].scan_type.shift =3D 0;
> +
> +	return cnt + 1;
> +}
> +
> +static int ad7280_attr_init(struct ad7280_state *st)
> +{
> +	int dev, ch, cnt;
> +
> +	st->iio_attr =3D kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1=
) *
> +				AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
> +	if (st->iio_attr =3D=3D NULL)
> +		return -ENOMEM;
> +
> +	for (dev =3D 0, cnt =3D 0; dev <=3D st->slave_num; dev++)
> +		for (ch =3D AD7280A_CELL_VOLTAGE_1; ch <=3D AD7280A_CELL_VOLTAGE_6=
;
> +			ch++, cnt++) {
> +			st->iio_attr[cnt].address =3D
> +				AD7280A_DEVADDR(dev) << 8 | ch;
> +			st->iio_attr[cnt].dev_attr.attr.mode =3D
> +				S_IWUSR | S_IRUGO;
> +			st->iio_attr[cnt].dev_attr.show =3D
> +				ad7280_show_balance_sw;
> +			st->iio_attr[cnt].dev_attr.store =3D
> +				ad7280_store_balance_sw;
> +			st->iio_attr[cnt].dev_attr.attr.name =3D
> +				kasprintf(GFP_KERNEL, "in%d_balance_switch_en",
> +					  (dev * AD7280A_CELLS_PER_DEV) + ch);
> +			ad7280_attributes[cnt] =3D
> +				&st->iio_attr[cnt].dev_attr.attr;
> +			cnt++;
> +			st->iio_attr[cnt].address =3D
> +				AD7280A_DEVADDR(dev) << 8 |
> +				(AD7280A_CB1_TIMER + ch);
> +			st->iio_attr[cnt].dev_attr.attr.mode =3D
> +				S_IWUSR | S_IRUGO;
> +			st->iio_attr[cnt].dev_attr.show =3D
> +				ad7280_show_balance_timer;
> +			st->iio_attr[cnt].dev_attr.store =3D
> +				ad7280_store_balance_timer;
> +			st->iio_attr[cnt].dev_attr.attr.name =3D
> +				kasprintf(GFP_KERNEL, "in%d_balance_timer",
> +					  (dev * AD7280A_CELLS_PER_DEV) + ch);
> +			ad7280_attributes[cnt] =3D
> +				&st->iio_attr[cnt].dev_attr.attr;
> +		}
> +
> +	ad7280_attributes[cnt] =3D NULL;
> +
> +	return 0;
> +}
> +
> +static ssize_t ad7280_read_channel_config(struct device *dev,
> +					struct device_attribute *attr,
> +					char *buf)
> +{
> +	struct iio_dev *dev_info =3D dev_get_drvdata(dev);
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
> +	unsigned val;
> +
> +	switch (this_attr->address) {
> +	case AD7280A_CELL_OVERVOLTAGE:
> +		val =3D 1000 + (st->cell_threshhigh * 1568) / 100;
> +		break;
> +	case AD7280A_CELL_UNDERVOLTAGE:
> +		val =3D 1000 + (st->cell_threshlow * 1568) / 100;
> +		break;
> +	case AD7280A_AUX_ADC_OVERVOLTAGE:
> +		val =3D (st->aux_threshhigh * 196) / 10;
> +		break;
> +	case AD7280A_AUX_ADC_UNDERVOLTAGE:
> +		val =3D (st->aux_threshlow * 196) / 10;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return sprintf(buf, "%d\n", val);
> +}
> +
> +static ssize_t ad7280_write_channel_config(struct device *dev,
> +					 struct device_attribute *attr,
> +					 const char *buf,
> +					 size_t len)
> +{
> +	struct iio_dev *dev_info =3D dev_get_drvdata(dev);
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
> +
> +	long val;
> +	int ret;
> +
> +	ret =3D strict_strtol(buf, 10, &val);
> +	if (ret)
> +		return ret;
> +
> +	switch (this_attr->address) {
> +	case AD7280A_CELL_OVERVOLTAGE:
> +	case AD7280A_CELL_UNDERVOLTAGE:
> +		val =3D ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
> +		break;
> +	case AD7280A_AUX_ADC_OVERVOLTAGE:
> +	case AD7280A_AUX_ADC_UNDERVOLTAGE:
> +		val =3D (val * 10) / 196; /* LSB 19.6mV */
> +		break;
> +	default:
> +		return -EFAULT;
> +	}
> +
> +	val =3D clamp(val, 0L, 0xFFL);
> +
> +	mutex_lock(&dev_info->mlock);
> +	switch (this_attr->address) {
> +	case AD7280A_CELL_OVERVOLTAGE:
> +		st->cell_threshhigh =3D val;
> +		break;
> +	case AD7280A_CELL_UNDERVOLTAGE:
> +		st->cell_threshlow =3D val;
> +		break;
> +	case AD7280A_AUX_ADC_OVERVOLTAGE:
> +		st->aux_threshhigh =3D val;
> +		break;
> +	case AD7280A_AUX_ADC_UNDERVOLTAGE:
> +		st->aux_threshlow =3D val;
> +		break;
> +	}
> +
> +	ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER,
> +			   this_attr->address, 1, val);
> +
> +	mutex_unlock(&dev_info->mlock);
> +
> +	return ret ? ret : len;
> +}
> +
> +static irqreturn_t ad7280_event_handler(int irq, void *private)
> +{
> +	struct iio_dev *dev_info =3D private;
> +
> +	iio_push_event(dev_info, 0,
> +		       IIO_UNMOD_EVENT_CODE(IIO_IN,
> +					    0,
> +					    IIO_EV_TYPE_THRESH,
> +					    IIO_EV_DIR_EITHER),
> +		       iio_get_time_ns());
You have thresholds for temp and voltage below, but only voltage
event. I wonder if the right thing here is to issue two events
(subject to what is enabled).  If everything is turned on, there
doesn't seem to be anyway to tell what happened.  If the event
is consistent, I guess you could write a strobe function that would
enable events up the chain and see when it kicked in. That would
tell you where it came from.  No idea if one ever wants to know though.


> +
> +	return IRQ_HANDLED;
> +}
> +
> +static IIO_DEVICE_ATTR(in_thresh_low_value,
> +		       S_IRUGO | S_IWUSR,
> +		       ad7280_read_channel_config,
> +		       ad7280_write_channel_config,
> +		       AD7280A_CELL_UNDERVOLTAGE);
> +
> +static IIO_DEVICE_ATTR(in_thresh_high_value,
> +		       S_IRUGO | S_IWUSR,
> +		       ad7280_read_channel_config,
> +		       ad7280_write_channel_config,
> +		       AD7280A_CELL_OVERVOLTAGE);
> +
> +static IIO_DEVICE_ATTR(temp_thresh_low_value,
> +		       S_IRUGO | S_IWUSR,
> +		       ad7280_read_channel_config,
> +		       ad7280_write_channel_config,
> +		       AD7280A_AUX_ADC_UNDERVOLTAGE);
> +
> +static IIO_DEVICE_ATTR(temp_thresh_high_value,
> +		       S_IRUGO | S_IWUSR,
> +		       ad7280_read_channel_config,
> +		       ad7280_write_channel_config,
> +		       AD7280A_AUX_ADC_OVERVOLTAGE);
These are shared over all channels?  Hmm. That's not a case
I'd considered when writing the chan spec stuff for events,
perhaps we need to allow for 'shared' events.  Technically
the only abi meeting approach right now is to have these
for every channel.  So write one channels threshold value
then a read would tell you they have all changed.
> +
> +
> +static struct attribute *ad7280_event_attributes[] =3D {
> +	&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
> +	&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
> +	&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
> +	&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
> +	NULL,
> +};
> +
> +static struct attribute_group ad7280_event_attrs_group =3D {
> +	.attrs =3D ad7280_event_attributes,
> +};
> +
> +static int ad7280_read_raw(struct iio_dev *dev_info,
> +			   struct iio_chan_spec const *chan,
> +			   int *val,
> +			   int *val2,
> +			   long m)
> +{
> +	struct ad7280_state *st =3D iio_priv(dev_info);
> +	unsigned int scale_uv;
> +	int ret;
> +
> +	switch (m) {
> +	case 0:
> +		mutex_lock(&dev_info->mlock);
> +		switch (chan->type) {
> +		case IIO_IN:
> +			ret =3D ad7280_read_channel(st, chan->address >> 8,
> +						  chan->address & 0xFF);
> +			break;
> +		case IIO_IN_DIFF:
> +			ret =3D ad7280_read_all_channels(st, st->scan_cnt, NULL);
Err... Really need some explanation for what this channel is!
> +			break;
> +		default:
> +			ret =3D -EINVAL;
> +		}
> +		mutex_unlock(&dev_info->mlock);
> +
> +		if (ret < 0)
> +			return ret;
> +
> +		*val =3D ret;
> +
> +		return IIO_VAL_INT;
> +	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
> +		if ((chan->address & 0xFF) <=3D AD7280A_CELL_VOLTAGE_6)
> +			scale_uv =3D (4000 * 1000) >> AD7280A_BITS;
> +		else
> +			scale_uv =3D (5000 * 1000) >> AD7280A_BITS;
> +
> +		*val =3D  scale_uv / 1000;
> +		*val2 =3D (scale_uv % 1000) * 1000;
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	}
> +	return -EINVAL;
> +}
> +
> +static const struct iio_info ad7280_info =3D {
> +	.read_raw =3D &ad7280_read_raw,
> +	.num_interrupt_lines =3D 1,
> +	.event_attrs =3D &ad7280_event_attrs_group,
> +	.attrs =3D &ad7280_attrs_group,
> +	.driver_module =3D THIS_MODULE,
> +};
> +
> +static struct ad7280_platform_data ad7793_default_pdata =3D {
> +	.acquisition_time =3D AD7280A_ACQ_TIME_400ns,
> +	.conversion_averaging =3D AD7280A_CONV_AVG_DIS,
> +	.thermistor_term_en =3D true,
> +};
const?
> +
> +static int __devinit ad7280_probe(struct spi_device *spi)
> +{
> +	struct ad7280_platform_data *pdata =3D spi->dev.platform_data;
> +	struct ad7280_state *st;
> +	int ret, regdone =3D 0;
> +	const unsigned short tACQ_ns[4] =3D {465, 1010, 1460, 1890};
> +	const unsigned short nAVG[4] =3D {1, 2, 4, 8};
> +	struct iio_dev *indio_dev =3D iio_allocate_device(sizeof(*st));
> +
> +	if (indio_dev =3D=3D NULL)
> +		return -ENOMEM;
> +
> +	st =3D iio_priv(indio_dev);
> +	spi_set_drvdata(spi, indio_dev);
> +	st->spi =3D spi;
> +
> +	if (!pdata)
> +		pdata =3D &ad7793_default_pdata;
> +
> +	ad7280_crc8_build_table(st->crc_tab);
> +
> +	st->spi->max_speed_hz =3D AD7280A_MAX_SPI_CLK_Hz;
> +	st->spi->mode =3D SPI_MODE_1;
> +	spi_setup(st->spi);
> +
> +	st->ctrl_lb =3D AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & =
0x3);
> +	st->ctrl_hb =3D AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averagin=
g
> +			& 0x3) | (pdata->thermistor_term_en ?
> +			AD7280A_CTRL_LB_THERMISTOR_EN : 0);
> +
> +	ret =3D ad7280_chain_setup(st);
> +	if (ret < 0)
> +		goto error_free_device;
> +
> +	st->slave_num =3D ret;
> +	st->scan_cnt =3D (st->slave_num + 1) * AD7280A_NUM_CH;
> +	st->cell_threshhigh =3D 0xFF;
> +	st->aux_threshhigh =3D 0xFF;
> +
> +	/*
> +	 * Total Conversion Time =3D ((tACQ + tCONV) *
> +	 *			   (Number of Conversions per Part)) =E2=88=92
> +	 *			   tACQ + ((N - 1) * tDELAY)
> +	 *
> +	 * Readback Delay =3D Total Conversion Time + tWAIT
> +	 */
> +
> +	st->readback_delay_us =3D
> +		((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
> +		(AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
> +		- tACQ_ns[pdata->acquisition_time & 0x3] +
> +		st->slave_num * 250;
> +
> +	/* Convert to usecs */
> +	st->readback_delay_us =3D DIV_ROUND_UP(st->readback_delay_us, 1000)=
;
> +	st->readback_delay_us +=3D 5; /* Add tWAIT */
> +
> +	indio_dev->name =3D spi_get_device_id(spi)->name;
> +	indio_dev->dev.parent =3D &spi->dev;
> +	indio_dev->modes =3D INDIO_DIRECT_MODE;
> +
> +	ret =3D ad7280_channel_init(st);
> +	if (ret < 0)
> +		goto error_free_device;
> +
> +	indio_dev->num_channels =3D ret;
> +	indio_dev->channels =3D st->channels;
> +	indio_dev->info =3D &ad7280_info;
> +
> +	ret =3D ad7280_attr_init(st);
> +	if (ret < 0)
> +		goto error_free_channels;
> +
> +	ret =3D iio_device_register(indio_dev);
> +	if (ret)
> +		goto error_free_attr;
> +	regdone =3D 1;
> +
> +	if (spi->irq > 0) {
> +		ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER,
> +				   AD7280A_ALERT, 1,
> +				   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
> +		if (ret)
> +			goto error_free_attr;
> +
> +		ret =3D ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
> +				   AD7280A_ALERT, 0,
> +				   AD7280A_ALERT_GEN_STATIC_HIGH |
> +				   (pdata->chain_last_alert_ignore & 0xF));
> +		if (ret)
> +			goto error_free_attr;
> +
> +		ret =3D request_threaded_irq(spi->irq,
> +					   NULL,
> +					   ad7280_event_handler,
> +					   IRQF_TRIGGER_FALLING |
> +					   IRQF_ONESHOT,
> +					   indio_dev->name,
> +					   indio_dev);
> +		if (ret)
> +			goto error_free_attr;
> +	}
> +
> +	return 0;
> +
> +error_free_attr:
> +	kfree(st->iio_attr);
> +
> +error_free_channels:
> +	kfree(st->channels);
> +
> +error_free_device:
> +	if (regdone)
> +		iio_device_unregister(indio_dev);
> +	else
> +		iio_free_device(indio_dev);
> +
> +	return ret;
> +}
> +
> +static int __devexit ad7280_remove(struct spi_device *spi)
> +{
> +	struct iio_dev *indio_dev =3D spi_get_drvdata(spi);
> +	struct ad7280_state *st =3D iio_priv(indio_dev);
> +
> +	if (spi->irq > 0)
> +		free_irq(spi->irq, indio_dev);
> +
> +	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
> +			AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
> +
> +	kfree(st->channels);
> +	kfree(st->iio_attr);
> +	iio_device_unregister(indio_dev);
> +
> +	return 0;
> +}
> +
> +static const struct spi_device_id ad7280_id[] =3D {
> +	{"ad7280a", 0},
> +	{}
> +};
> +
> +static struct spi_driver ad7280_driver =3D {
> +	.driver =3D {
> +		.name	=3D "ad7280",
> +		.bus	=3D &spi_bus_type,
> +		.owner	=3D THIS_MODULE,
> +	},
> +	.probe		=3D ad7280_probe,
> +	.remove		=3D __devexit_p(ad7280_remove),
> +	.id_table	=3D ad7280_id,
> +};
> +
> +static int __init ad7280_init(void)
> +{
> +	return spi_register_driver(&ad7280_driver);
> +}
> +module_init(ad7280_init);
> +
> +static void __exit ad7280_exit(void)
> +{
> +	spi_unregister_driver(&ad7280_driver);
> +}
> +module_exit(ad7280_exit);
> +
> +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
> +MODULE_DESCRIPTION("Analog Devices AD7280A");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/staging/iio/adc/ad7280a.h b/drivers/staging/iio/=
adc/ad7280a.h
> new file mode 100644
> index 0000000..20400b0
> --- /dev/null
> +++ b/drivers/staging/iio/adc/ad7280a.h
> @@ -0,0 +1,38 @@
> +/*
> + * AD7280A Lithium Ion Battery Monitoring System
> + *
> + * Copyright 2011 Analog Devices Inc.
> + *
> + * Licensed under the GPL-2.
> + */
> +
> +#ifndef IIO_ADC_AD7280_H_
> +#define IIO_ADC_AD7280_H_
> +
> +/*
> + * TODO: struct ad7280_platform_data needs to go into include/linux/=
iio
> + */
> +
> +#define AD7280A_ACQ_TIME_400ns			0
> +#define AD7280A_ACQ_TIME_800ns			1
> +#define AD7280A_ACQ_TIME_1200ns			2
> +#define AD7280A_ACQ_TIME_1600ns			3
> +
> +#define AD7280A_CONV_AVG_DIS			0
> +#define AD7280A_CONV_AVG_2			1
> +#define AD7280A_CONV_AVG_4			2
> +#define AD7280A_CONV_AVG_8			3
> +
> +#define AD7280A_ALERT_REMOVE_VIN5		(1 << 2)
> +#define AD7280A_ALERT_REMOVE_VIN4_VIN5		(2 << 2)
> +#define AD7280A_ALERT_REMOVE_AUX5		(1 << 0)
> +#define AD7280A_ALERT_REMOVE_AUX4_AUX5		(2 << 0)
> +
> +struct ad7280_platform_data {
> +	unsigned acquisition_time;
> +	unsigned conversion_averaging;
> +	unsigned chain_last_alert_ignore;
> +	bool thermistor_term_en;
> +};
> +
> +#endif /* IIO_ADC_AD7280_H_ */


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 11:43   ` Jonathan Cameron
@ 2011-07-18 12:48     ` Michael Hennerich
  2011-07-18 12:56       ` Jonathan Cameron
  0 siblings, 1 reply; 13+ messages in thread
From: Michael Hennerich @ 2011-07-18 12:48 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

On 07/18/2011 01:43 PM, Jonathan Cameron wrote:
> On 07/15/11 13:59, michael.hennerich@analog.com wrote:
>> From: Michael Hennerich<michael.hennerich@analog.com>
> Hi Michael, although anyone reading the datasheets will quickly
> discover that this isn't a simple laptop style battery monitor,
> it's probably worth making that clear in the patch title or
> at very least here.
>
> Driver is pretty clear. Couple of nitpicks / queries inline.
>
> Thanks
>
> Jonathan
>>
>> Signed-off-by: Michael Hennerich<michael.hennerich@analog.com>
>> ---
>>   .../iio/Documentation/sysfs-bus-iio-adc-ad7280a    |   21 +
>>   drivers/staging/iio/adc/Kconfig                    |   10 +
>>   drivers/staging/iio/adc/Makefile                   |    1 +
>>   drivers/staging/iio/adc/ad7280a.c                  |  939 ++++++++++=
++++++++++
>>   drivers/staging/iio/adc/ad7280a.h                  |   38 +
>>   5 files changed, 1009 insertions(+), 0 deletions(-)
>>   create mode 100644 drivers/staging/iio/Documentation/sysfs-bus-iio-a=
dc-ad7280a
>>   create mode 100644 drivers/staging/iio/adc/ad7280a.c
>>   create mode 100644 drivers/staging/iio/adc/ad7280a.h
>>
>> diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad728=
0a b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
>> new file mode 100644
>> index 0000000..fe90bd9
>> --- /dev/null
>> +++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
>> @@ -0,0 +1,21 @@
>> +What:                /sys/bus/iio/devices/deviceX/inY_balance_switch_=
en
>> +KernelVersion:       3.0.0
>> +Contact:     linux-iio@vger.kernel.org
>> +Description:
>> +             Writing 1 enables the cell balance output switch corresp=
onding
>> +             to input Y. Writing 0 disables it. If the inY_balance_ti=
mer is
>> +             set to a none zero value, the corresponding switch will =
enable
>> +             for the programmed amount of time, before it automatical=
ly
>> +             disables.
>> +
>> +What:                /sys/bus/iio/devices/deviceX/inY_balance_timer
>> +KernelVersion:       3.0.0
>> +Contact:     linux-iio@vger.kernel.org
>> +Description:
>> +             The inY_balance_timer file allows the user to program in=
dividual
>> +             times for each cell balance output. The AD7280A allows t=
he user
>> +             to set the timer to a value from 0 minutes to 36.9 minut=
es.
>> +             The resolution of the timer is 71.5 sec. Corresponding t=
o a
>> +             valid range of 0..31. When the timer value is set 0,
>> +             the timer is disabled. The cell balance outputs are cont=
rolled
>> +             only by inY_balance_switch_en.
> I'd prefer to see that in SI units and do the conversion to the interna=
l units
> in the driver.
ok
>> diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc=
/Kconfig
>> index b39f2e1..60de7d7 100644
>> --- a/drivers/staging/iio/adc/Kconfig
>> +++ b/drivers/staging/iio/adc/Kconfig
>> @@ -182,6 +182,16 @@ config ADT7410
>>          Say yes here to build support for Analog Devices ADT7410
>>          temperature sensors.
>>
>> +config AD7280
>> +     tristate "Analog Devices AD7280A Lithium Ion Battery Monitoring =
System"
>> +     depends on SPI
>> +     help
>> +       Say yes here to build support for Analog Devices AD7280A
>> +       Lithium Ion Battery Monitoring System.
>> +
>> +       To compile this driver as a module, choose M here: the
>> +       module will be called ad7280a
>> +
>>   config MAX1363
>>        tristate "Maxim max1363 ADC driver"
>>        depends on I2C
>> diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/ad=
c/Makefile
>> index f020351..634a55f 100644
>> --- a/drivers/staging/iio/adc/Makefile
>> +++ b/drivers/staging/iio/adc/Makefile
>> @@ -40,3 +40,4 @@ obj-$(CONFIG_AD7816) +=3D ad7816.o
>>   obj-$(CONFIG_ADT75) +=3D adt75.o
>>   obj-$(CONFIG_ADT7310) +=3D adt7310.o
>>   obj-$(CONFIG_ADT7410) +=3D adt7410.o
>> +obj-$(CONFIG_AD7280) +=3D ad7280a.o
>> diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/a=
dc/ad7280a.c
>> new file mode 100644
>> index 0000000..0efef55
>> --- /dev/null
>> +++ b/drivers/staging/iio/adc/ad7280a.c
>> @@ -0,0 +1,939 @@
>> +/*
>> + * AD7280A Lithium Ion Battery Monitoring System
>> + *
>> + * Copyright 2011 Analog Devices Inc.
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include<linux/device.h>
>> +#include<linux/kernel.h>
>> +#include<linux/slab.h>
>> +#include<linux/sysfs.h>
>> +#include<linux/spi/spi.h>
>> +#include<linux/err.h>
>> +#include<linux/delay.h>
>> +#include<linux/interrupt.h>
>> +
>> +#include "../iio.h"
>> +#include "../sysfs.h"
>> +#include "adc.h"
>> +
>> +#include "ad7280a.h"
>> +
>> +/* Registers */
>> +#define AD7280A_CELL_VOLTAGE_1               0x0  /* D11 to D0, Read =
only */
>> +#define AD7280A_CELL_VOLTAGE_2               0x1  /* D11 to D0, Read =
only */
>> +#define AD7280A_CELL_VOLTAGE_3               0x2  /* D11 to D0, Read =
only */
>> +#define AD7280A_CELL_VOLTAGE_4               0x3  /* D11 to D0, Read =
only */
>> +#define AD7280A_CELL_VOLTAGE_5               0x4  /* D11 to D0, Read =
only */
>> +#define AD7280A_CELL_VOLTAGE_6               0x5  /* D11 to D0, Read =
only */
>> +#define AD7280A_AUX_ADC_1            0x6  /* D11 to D0, Read only */
>> +#define AD7280A_AUX_ADC_2            0x7  /* D11 to D0, Read only */
>> +#define AD7280A_AUX_ADC_3            0x8  /* D11 to D0, Read only */
>> +#define AD7280A_AUX_ADC_4            0x9  /* D11 to D0, Read only */
>> +#define AD7280A_AUX_ADC_5            0xA  /* D11 to D0, Read only */
>> +#define AD7280A_AUX_ADC_6            0xB  /* D11 to D0, Read only */
>> +#define AD7280A_SELF_TEST            0xC  /* D11 to D0, Read only */
>> +#define AD7280A_CONTROL_HB           0xD  /* D15 to D8, Read/write */
>> +#define AD7280A_CONTROL_LB           0xE  /* D7 to D0, Read/write */
>> +#define AD7280A_CELL_OVERVOLTAGE     0xF  /* D7 to D0, Read/write */
>> +#define AD7280A_CELL_UNDERVOLTAGE    0x10 /* D7 to D0, Read/write */
>> +#define AD7280A_AUX_ADC_OVERVOLTAGE  0x11 /* D7 to D0, Read/write */
>> +#define AD7280A_AUX_ADC_UNDERVOLTAGE 0x12 /* D7 to D0, Read/write */
>> +#define AD7280A_ALERT                        0x13 /* D7 to D0, Read/w=
rite */
>> +#define AD7280A_CELL_BALANCE         0x14 /* D7 to D0, Read/write */
>> +#define AD7280A_CB1_TIMER            0x15 /* D7 to D0, Read/write */
>> +#define AD7280A_CB2_TIMER            0x16 /* D7 to D0, Read/write */
>> +#define AD7280A_CB3_TIMER            0x17 /* D7 to D0, Read/write */
>> +#define AD7280A_CB4_TIMER            0x18 /* D7 to D0, Read/write */
>> +#define AD7280A_CB5_TIMER            0x19 /* D7 to D0, Read/write */
>> +#define AD7280A_CB6_TIMER            0x1A /* D7 to D0, Read/write */
>> +#define AD7280A_PD_TIMER             0x1B /* D7 to D0, Read/write */
>> +#define AD7280A_READ                 0x1C /* D7 to D0, Read/write */
>> +#define AD7280A_CNVST_CONTROL                0x1D /* D7 to D0, Read/w=
rite */
>> +
>> +/* Bits and Masks */
>> +#define AD7280A_CTRL_HB_CONV_INPUT_ALL                       (0<<  6)
>> +#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4    (1<<  6)
>> +#define AD7280A_CTRL_HB_CONV_INPUT_6CELL             (2<<  6)
>> +#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST         (3<<  6)
>> +#define AD7280A_CTRL_HB_CONV_RES_READ_ALL            (0<<  4)
>> +#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4 (1<<  4)
>> +#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL          (2<<  4)
>> +#define AD7280A_CTRL_HB_CONV_RES_READ_NO             (3<<  4)
>> +#define AD7280A_CTRL_HB_CONV_START_CNVST             (0<<  3)
>> +#define AD7280A_CTRL_HB_CONV_START_CS                        (1<<  3)
>> +#define AD7280A_CTRL_HB_CONV_AVG_DIS                 (0<<  1)
>> +#define AD7280A_CTRL_HB_CONV_AVG_2                   (1<<  1)
>> +#define AD7280A_CTRL_HB_CONV_AVG_4                   (2<<  1)
>> +#define AD7280A_CTRL_HB_CONV_AVG_8                   (3<<  1)
>> +#define AD7280A_CTRL_HB_CONV_AVG(x)                  ((x)<<  1)
>> +#define AD7280A_CTRL_HB_PWRDN_SW                     (1<<  0)
>> +
>> +#define AD7280A_CTRL_LB_SWRST                                (1<<  7)
>> +#define AD7280A_CTRL_LB_ACQ_TIME_400ns                       (0<<  5)
>> +#define AD7280A_CTRL_LB_ACQ_TIME_800ns                       (1<<  5)
>> +#define AD7280A_CTRL_LB_ACQ_TIME_1200ns                      (2<<  5)
>> +#define AD7280A_CTRL_LB_ACQ_TIME_1600ns                      (3<<  5)
>> +#define AD7280A_CTRL_LB_ACQ_TIME(x)                  ((x)<<  5)
>> +#define AD7280A_CTRL_LB_MUST_SET                     (1<<  4)
>> +#define AD7280A_CTRL_LB_THERMISTOR_EN                        (1<<  3)
>> +#define AD7280A_CTRL_LB_LOCK_DEV_ADDR                        (1<<  2)
>> +#define AD7280A_CTRL_LB_INC_DEV_ADDR                 (1<<  1)
>> +#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN            (1<<  0)
>> +
>> +#define AD7280A_ALERT_GEN_STATIC_HIGH                        (1<<  6)
>> +#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN           (3<<  6)
>> +
>> +#define RES_MASK(bits)                       ((1<<  (bits)) - 1)
>> +#define AD7280A_MAX_SPI_CLK_Hz               700000 /*<  1MHz */
>> +#define AD7280A_MAX_CHAIN            8
>> +#define AD7280A_CELLS_PER_DEV                6
>> +#define AD7280A_BITS                 12
>> +#define AD7280A_NUM_CH                       (AD7280A_AUX_ADC_6 - \
>> +                                     AD7280A_CELL_VOLTAGE_1 + 1)
>> +
>> +#define AD7280A_DEVADDR_MASTER               0
>> +#define AD7280A_DEVADDR_ALL          0x1F
>> +/* 5-bit device address is sent LSB first */
>> +#define AD7280A_DEVADDR(addr)        (((addr&  0x1)<<  4) | ((addr&  =
0x2)<<  3) | \
>> +                             (addr&  0x4) | ((addr&  0x8)>>  3) | \
>> +                             ((addr&  0x10)>>  4))
>> +
> Probably squish this into the one user for clarity.
ok
>> +#define AD7280A_WRITE(DEVADDR, REGADDR, REGDATA, ADDRALL) \
>> +                   ((DEVADDR)<<  27 | (REGADDR)<<  21 | \
>> +                   ((REGDATA)&  0xFF)<<  13 | ADDRALL<<  12)
>> +
> Same with this one.
ok
>> +#define AD7280A_APPEND_CRC(VAL, CRC) ((VAL) | (CRC)<<  3 | 0x2)
>> +
>> +/*
>> + * AD7280 CRC
>> + *
>> + * P(x) =3D x^8 + x^5 + x^3 + x^2 + x^1 + x^0 =3D 0b100101111 =3D>  0=
x2F
>> + */
>> +#define POLYNOM              0x2F
>> +#define POLYNOM_ORDER        8
>> +#define HIGHBIT              1<<  (POLYNOM_ORDER - 1);
>> +
>> +struct ad7280_state {
>> +     struct spi_device               *spi;
>> +     struct iio_chan_spec            *channels;
>> +     struct iio_dev_attr             *iio_attr;
>> +     int                             slave_num;
>> +     int                             scan_cnt;
>> +     int                             readback_delay_us;
>> +     unsigned char                   crc_tab[256];
>> +     unsigned char                   ctrl_hb;
>> +     unsigned char                   ctrl_lb;
>> +     unsigned char                   cell_threshhigh;
>> +     unsigned char                   cell_threshlow;
>> +     unsigned char                   aux_threshhigh;
>> +     unsigned char                   aux_threshlow;
>> +     unsigned char                   cb_mask[AD7280A_MAX_CHAIN];
>> +};
>> +
>> +static void ad7280_crc8_build_table(unsigned char *crc_tab)
>> +{
>> +     unsigned char bit, crc;
>> +     int cnt, i;
>> +
>> +     for (cnt =3D 0; cnt<  256; cnt++) {
>> +             crc =3D cnt;
>> +             for (i =3D 0; i<  8; i++) {
>> +                     bit =3D crc&  HIGHBIT;
>> +                     crc<<=3D 1;
>> +                     if (bit)
>> +                             crc ^=3D POLYNOM;
>> +             }
>> +             crc_tab[cnt] =3D crc;
>> +     }
>> +}
>> +
>> +static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigne=
d val)
>> +{
>> +     unsigned char crc;
>> +
>> +     crc =3D crc_tab[val>>  16&  0xFF];
>> +     crc =3D crc_tab[crc ^ (val>>  8&  0xFF)];
>> +
>> +     return  crc ^ (val&  0xFF);
>> +}
>> +
>> +static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
>> +{
>> +     unsigned char crc =3D ad7280_calc_crc8(st->crc_tab, val>>  10);
>> +
>> +     if (crc !=3D ((val>>  2)&  0xFF))
>> +             return -EIO;
>> +
>> +     return 0;
>> +}
>> +
> Any real reason for this tiny wrapper?  I'd squash into the call
> site given there is only one of them.
Well for consistency - there is a __read why not having also a __write
which does endianess conversion and calling the bus method.

But right you are - there is only one user.
I'll squash it.

>> +static int __ad7280_write32(struct spi_device *spi, unsigned val)
>> +{
>> +     u32 data =3D cpu_to_be32(val);
>> +
>> +     return spi_write(spi,&data, 4);
>> +}
>> +
> This needs an explanatory comment.
ok
>> +static void ad7280_delay(struct ad7280_state *st)
>> +{
>> +     if (st->readback_delay_us<  50)
>> +             udelay(st->readback_delay_us);
>> +     else
>> +             msleep(1);
>> +}
>> +
>> +static int __ad7280_read32(struct spi_device *spi, unsigned *val)
>> +{
> Please explain the magic constant.
it's always the same, so calculating a CRC doesn't make much sense.
I'll add a comment.

>> +     unsigned rx_buf, tx_buf =3D cpu_to_be32(0xF800030A);
>> +     int ret;
>> +
>> +     struct spi_transfer t =3D {
>> +             .tx_buf =3D&tx_buf,
>> +             .rx_buf =3D&rx_buf,
>> +             .len =3D 4,
>> +     };
>> +     struct spi_message m;
>> +
>> +     spi_message_init(&m);
>> +     spi_message_add_tail(&t,&m);
>> +
>> +     ret =3D spi_sync(spi,&m);
>> +     if (ret)
>> +             return ret;
>> +
>> +     *val =3D be32_to_cpu(rx_buf);
>> +
>> +     return 0;
>> +}
>> +
>> +static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
>> +                     unsigned addr, bool all, unsigned val)
>> +{
>> +
>> +     unsigned reg =3D AD7280A_WRITE(devaddr, addr, val, all);
>> +
>> +     reg =3D AD7280A_APPEND_CRC(reg,
>> +             ad7280_calc_crc8(st->crc_tab, reg>>  11));
>> +
>> +     return __ad7280_write32(st->spi, reg);
>> +}
>> +
>> +static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
>> +                     unsigned addr)
>> +{
>> +     int ret;
>> +     unsigned tmp;
> This would benefit form a few explanatory comments.
ok
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL=
_HB, 1,
>> +                     AD7280A_CTRL_HB_CONV_INPUT_ALL |
>> +                     AD7280A_CTRL_HB_CONV_RES_READ_NO |
>> +                     st->ctrl_hb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
>> +                     AD7280A_CTRL_HB_CONV_INPUT_ALL |
>> +                     AD7280A_CTRL_HB_CONV_RES_READ_ALL |
>> +                     st->ctrl_hb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, devaddr, AD7280A_READ, 0, addr<<  2);
>> +     if (ret)
>> +             return ret;
>> +
>> +     __ad7280_read32(st->spi,&tmp);
>> +
>> +     if (ad7280_check_crc(st, tmp))
>> +             return -EIO;
>> +
>> +     if (((tmp>>  27) !=3D devaddr) || (((tmp>>  21)&  0x3F) !=3D add=
r))
>> +             return -EFAULT;
>> +
>> +     return (tmp>>  13)&  0xFF;
>> +}
>> +
>> +static int ad7280_read_channel(struct ad7280_state *st, unsigned deva=
ddr,
>> +                            unsigned addr)
>> +{
>> +     int ret;
>> +     unsigned tmp;
>> +
>> +     ret =3D ad7280_write(st, devaddr, AD7280A_READ, 0, addr<<  2);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL=
_HB, 1,
>> +                     AD7280A_CTRL_HB_CONV_INPUT_ALL |
>> +                     AD7280A_CTRL_HB_CONV_RES_READ_NO |
>> +                     st->ctrl_hb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
>> +                     AD7280A_CTRL_HB_CONV_INPUT_ALL |
>> +                     AD7280A_CTRL_HB_CONV_RES_READ_ALL |
>> +                     AD7280A_CTRL_HB_CONV_START_CS |
>> +                     st->ctrl_hb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ad7280_delay(st);
>> +
>> +     __ad7280_read32(st->spi,&tmp);
>> +
>> +     if (ad7280_check_crc(st, tmp))
>> +             return -EIO;
>> +
>> +     if (((tmp>>  27) !=3D devaddr) || (((tmp>>  23)&  0xF) !=3D addr=
))
>> +             return -EFAULT;
>> +
>> +     return (tmp>>  11)&  0xFFF;
>> +}
>> +
>> +static int ad7280_read_all_channels(struct ad7280_state *st, unsigned=
 cnt,
>> +                          unsigned *array)
>> +{
>> +     int i, ret;
>> +     unsigned tmp, sum =3D 0;
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1=
,
>> +                        AD7280A_CELL_VOLTAGE_1<<  2);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL=
_HB, 1,
>> +                     AD7280A_CTRL_HB_CONV_INPUT_ALL |
>> +                     AD7280A_CTRL_HB_CONV_RES_READ_ALL |
>> +                     AD7280A_CTRL_HB_CONV_START_CS |
>> +                     st->ctrl_hb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ad7280_delay(st);
>> +
>> +     for (i =3D 0; i<  cnt; i++) {
>> +             __ad7280_read32(st->spi,&tmp);
>> +
>> +             if (ad7280_check_crc(st, tmp))
>> +                     return -EIO;
>> +
>> +             if (array)
>> +                     array[i] =3D tmp;
>> +             /* only sum cell voltages */
>> +             if (((tmp>>  23)&  0xF)<=3D AD7280A_CELL_VOLTAGE_6)
>> +                     sum +=3D ((tmp>>  11)&  0xFFF);
>> +     }
>> +
>> +     return sum;
>> +}
>> +
>> +static int ad7280_chain_setup(struct ad7280_state *st)
>> +{
>> +     unsigned val, n;
>> +     int ret;
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL=
_LB, 1,
>> +                     AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
>> +                     AD7280A_CTRL_LB_LOCK_DEV_ADDR |
>> +                     AD7280A_CTRL_LB_MUST_SET |
>> +                     AD7280A_CTRL_LB_SWRST |
>> +                     st->ctrl_lb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL=
_LB, 1,
>> +                     AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
>> +                     AD7280A_CTRL_LB_LOCK_DEV_ADDR |
>> +                     AD7280A_CTRL_LB_MUST_SET |
>> +                     st->ctrl_lb);
>> +     if (ret)
>> +             return ret;
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1=
,
>> +                     AD7280A_CONTROL_LB<<  2);
>> +     if (ret)
>> +             return ret;
>> +
>> +     for (n =3D 0; n<=3D AD7280A_MAX_CHAIN; n++) {
>> +             __ad7280_read32(st->spi,&val);
>> +             if (val =3D=3D 0)
>> +                     return n - 1;
>> +
>> +             if (ad7280_check_crc(st, val))
>> +                     return -EIO;
>> +
>> +             if (n !=3D AD7280A_DEVADDR(val>>  27))
>> +                     return -EIO;
>> +     }
>> +
>> +     return -EFAULT;
>> +}
>> +
>> +static ssize_t ad7280_show_balance_sw(struct device *dev,
>> +                                     struct device_attribute *attr,
>> +                                     char *buf)
>> +{
>> +     struct iio_dev *dev_info =3D dev_get_drvdata(dev);
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
>> +
>> +     return sprintf(buf, "%d\n",
>> +                    !!(st->cb_mask[this_attr->address>>  8]&
>> +                    (1<<  ((this_attr->address&  0xFF) + 2))));
>> +}
>> +
>> +static ssize_t ad7280_store_balance_sw(struct device *dev,
>> +                                      struct device_attribute *attr,
>> +                                      const char *buf,
>> +                                      size_t len)
>> +{
>> +     struct iio_dev *dev_info =3D dev_get_drvdata(dev);
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
>> +     bool readin;
>> +     int ret;
>> +     unsigned devaddr, ch;
>> +
>> +     ret =3D strtobool(buf,&readin);
>> +     if (ret)
>> +             return ret;
>> +
>> +     devaddr =3D this_attr->address>>  8;
>> +     ch =3D this_attr->address&  0xFF;
>> +
>> +     mutex_lock(&dev_info->mlock);
>> +     if (readin)
>> +             st->cb_mask[devaddr] |=3D 1<<  (ch + 2);
>> +     else
>> +             st->cb_mask[devaddr]&=3D ~(1<<  (ch + 2));
>> +
>> +     ret =3D ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
>> +                        0, st->cb_mask[devaddr]);
>> +     mutex_unlock(&dev_info->mlock);
>> +
>> +     return ret ? ret : len;
>> +}
>> +
>> +static ssize_t ad7280_show_balance_timer(struct device *dev,
>> +                                     struct device_attribute *attr,
>> +                                     char *buf)
>> +{
>> +     struct iio_dev *dev_info =3D dev_get_drvdata(dev);
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
>> +     int ret;
>> +
>> +     mutex_lock(&dev_info->mlock);
>> +     ret =3D ad7280_read(st, this_attr->address>>  8,
>> +                     this_attr->address&  0xFF);
>> +     mutex_unlock(&dev_info->mlock);
>> +
>> +     if (ret<  0)
>> +             return ret;
>> +
>> +     return sprintf(buf, "%d\n", ret>>  3);
>> +}
>> +
>> +static ssize_t ad7280_store_balance_timer(struct device *dev,
>> +                                      struct device_attribute *attr,
>> +                                      const char *buf,
>> +                                      size_t len)
>> +{
>> +     struct iio_dev *dev_info =3D dev_get_drvdata(dev);
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
>> +     long val;
>> +     int ret;
>> +
>> +     ret =3D strict_strtol(buf, 10,&val);
>> +     if (ret)
>> +             return ret;
>> +
>> +     mutex_lock(&dev_info->mlock);
>> +     ret =3D ad7280_write(st, this_attr->address>>  8,
>> +                        this_attr->address&  0xFF,
>> +                        0, (val&  0x1F)<<  3);
>> +     mutex_unlock(&dev_info->mlock);
>> +
>> +     return ret ? ret : len;
>> +}
>> +
>> +static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
>> +                                        AD7280A_CELLS_PER_DEV * 2 + 1=
];
>> +
>> +static struct attribute_group ad7280_attrs_group =3D {
>> +     .attrs =3D ad7280_attributes,
>> +};
>> +
>> +static int ad7280_channel_init(struct ad7280_state *st)
>> +{
>> +     int dev, ch, cnt;
>> +
>> +     st->channels =3D kzalloc(sizeof(*st->channels) *
>> +                             ((st->slave_num + 1) * 12 + 2), GFP_KERN=
EL);
>> +     if (st->channels =3D=3D NULL)
>> +             return -ENOMEM;
>> +
>> +     for (dev =3D 0, cnt =3D 0; dev<=3D st->slave_num; dev++)
>> +             for (ch =3D AD7280A_CELL_VOLTAGE_1; ch<=3D AD7280A_AUX_A=
DC_6; ch++,
>> +                     cnt++) {
>> +                     if (ch<  AD7280A_AUX_ADC_1) {
>> +                             st->channels[cnt].type =3D IIO_IN;
>> +                             st->channels[cnt].channel =3D (dev * 6) =
+ ch;
>> +                     } else {
>> +                             st->channels[cnt].type =3D IIO_TEMP;
>> +                             st->channels[cnt].channel =3D (dev * 6) =
+ ch - 6;
>> +                     }
>> +                     st->channels[cnt].indexed =3D 1;
>> +                     st->channels[cnt].extend_name =3D NULL;
> Don't bother setting it then. You kzalloc'd the array.
ok
>> +                     st->channels[cnt].info_mask =3D
>> +
>> +                             (1<<  IIO_CHAN_INFO_SCALE_SHARED);
> Something strange in spacing above.
>> +                     st->channels[cnt].address =3D
>> +                             AD7280A_DEVADDR(dev)<<  8 | ch;
>> +                     st->channels[cnt].scan_index =3D cnt;
>> +                     st->channels[cnt].scan_type.sign =3D 'u';
>> +                     st->channels[cnt].scan_type.realbits =3D 12;
>> +                     st->channels[cnt].scan_type.storagebits =3D 32;
>> +                     st->channels[cnt].scan_type.shift =3D 0;
>> +             }
>> +
> I'm a little confused here. So we have 6 voltage and 6 temp channels fr=
om
> each part in the chain. What is this last one?
Thats the voltage across all cells in the stack.
>> +     st->channels[cnt].type =3D IIO_IN_DIFF;
>> +     st->channels[cnt].channel =3D 0;
>> +     st->channels[cnt].channel2 =3D dev * 6 - 1;
>> +     st->channels[cnt].address =3D AD7280A_DEVADDR(dev)<<  8 |
>> +             AD7280A_CELL_VOLTAGE_1;
>> +     st->channels[cnt].indexed =3D 1;
> Don't bother setting to NULL.
>> +     st->channels[cnt].extend_name =3D NULL;
>> +     st->channels[cnt].info_mask =3D (1<<  IIO_CHAN_INFO_SCALE_SHARED=
);
>> +     st->channels[cnt].scan_index =3D cnt;
>> +     st->channels[cnt].scan_type.sign =3D 'u';
>> +     st->channels[cnt].scan_type.realbits =3D 32;
>> +     st->channels[cnt].scan_type.storagebits =3D 32;
>> +     st->channels[cnt].scan_type.shift =3D 0;
>> +     cnt++;
>> +     st->channels[cnt].type =3D IIO_TIMESTAMP;
>> +     st->channels[cnt].channel =3D -1;
>> +     st->channels[cnt].scan_index =3D cnt;
>> +     st->channels[cnt].scan_type.sign =3D 's';
>> +     st->channels[cnt].scan_type.realbits =3D 64;
>> +     st->channels[cnt].scan_type.storagebits =3D 64;
>> +     st->channels[cnt].scan_type.shift =3D 0;
>> +
>> +     return cnt + 1;
>> +}
>> +
>> +static int ad7280_attr_init(struct ad7280_state *st)
>> +{
>> +     int dev, ch, cnt;
>> +
>> +     st->iio_attr =3D kzalloc(sizeof(*st->iio_attr) * (st->slave_num =
+ 1) *
>> +                             AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
>> +     if (st->iio_attr =3D=3D NULL)
>> +             return -ENOMEM;
>> +
>> +     for (dev =3D 0, cnt =3D 0; dev<=3D st->slave_num; dev++)
>> +             for (ch =3D AD7280A_CELL_VOLTAGE_1; ch<=3D AD7280A_CELL_=
VOLTAGE_6;
>> +                     ch++, cnt++) {
>> +                     st->iio_attr[cnt].address =3D
>> +                             AD7280A_DEVADDR(dev)<<  8 | ch;
>> +                     st->iio_attr[cnt].dev_attr.attr.mode =3D
>> +                             S_IWUSR | S_IRUGO;
>> +                     st->iio_attr[cnt].dev_attr.show =3D
>> +                             ad7280_show_balance_sw;
>> +                     st->iio_attr[cnt].dev_attr.store =3D
>> +                             ad7280_store_balance_sw;
>> +                     st->iio_attr[cnt].dev_attr.attr.name =3D
>> +                             kasprintf(GFP_KERNEL, "in%d_balance_swit=
ch_en",
>> +                                       (dev * AD7280A_CELLS_PER_DEV) =
+ ch);
>> +                     ad7280_attributes[cnt] =3D
>> +&st->iio_attr[cnt].dev_attr.attr;
>> +                     cnt++;
>> +                     st->iio_attr[cnt].address =3D
>> +                             AD7280A_DEVADDR(dev)<<  8 |
>> +                             (AD7280A_CB1_TIMER + ch);
>> +                     st->iio_attr[cnt].dev_attr.attr.mode =3D
>> +                             S_IWUSR | S_IRUGO;
>> +                     st->iio_attr[cnt].dev_attr.show =3D
>> +                             ad7280_show_balance_timer;
>> +                     st->iio_attr[cnt].dev_attr.store =3D
>> +                             ad7280_store_balance_timer;
>> +                     st->iio_attr[cnt].dev_attr.attr.name =3D
>> +                             kasprintf(GFP_KERNEL, "in%d_balance_time=
r",
>> +                                       (dev * AD7280A_CELLS_PER_DEV) =
+ ch);
>> +                     ad7280_attributes[cnt] =3D
>> +&st->iio_attr[cnt].dev_attr.attr;
>> +             }
>> +
>> +     ad7280_attributes[cnt] =3D NULL;
>> +
>> +     return 0;
>> +}
>> +
>> +static ssize_t ad7280_read_channel_config(struct device *dev,
>> +                                     struct device_attribute *attr,
>> +                                     char *buf)
>> +{
>> +     struct iio_dev *dev_info =3D dev_get_drvdata(dev);
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
>> +     unsigned val;
>> +
>> +     switch (this_attr->address) {
>> +     case AD7280A_CELL_OVERVOLTAGE:
>> +             val =3D 1000 + (st->cell_threshhigh * 1568) / 100;
>> +             break;
>> +     case AD7280A_CELL_UNDERVOLTAGE:
>> +             val =3D 1000 + (st->cell_threshlow * 1568) / 100;
>> +             break;
>> +     case AD7280A_AUX_ADC_OVERVOLTAGE:
>> +             val =3D (st->aux_threshhigh * 196) / 10;
>> +             break;
>> +     case AD7280A_AUX_ADC_UNDERVOLTAGE:
>> +             val =3D (st->aux_threshlow * 196) / 10;
>> +             break;
>> +     default:
>> +             return -EINVAL;
>> +     }
>> +
>> +     return sprintf(buf, "%d\n", val);
>> +}
>> +
>> +static ssize_t ad7280_write_channel_config(struct device *dev,
>> +                                      struct device_attribute *attr,
>> +                                      const char *buf,
>> +                                      size_t len)
>> +{
>> +     struct iio_dev *dev_info =3D dev_get_drvdata(dev);
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     struct iio_dev_attr *this_attr =3D to_iio_dev_attr(attr);
>> +
>> +     long val;
>> +     int ret;
>> +
>> +     ret =3D strict_strtol(buf, 10,&val);
>> +     if (ret)
>> +             return ret;
>> +
>> +     switch (this_attr->address) {
>> +     case AD7280A_CELL_OVERVOLTAGE:
>> +     case AD7280A_CELL_UNDERVOLTAGE:
>> +             val =3D ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
>> +             break;
>> +     case AD7280A_AUX_ADC_OVERVOLTAGE:
>> +     case AD7280A_AUX_ADC_UNDERVOLTAGE:
>> +             val =3D (val * 10) / 196; /* LSB 19.6mV */
>> +             break;
>> +     default:
>> +             return -EFAULT;
>> +     }
>> +
>> +     val =3D clamp(val, 0L, 0xFFL);
>> +
>> +     mutex_lock(&dev_info->mlock);
>> +     switch (this_attr->address) {
>> +     case AD7280A_CELL_OVERVOLTAGE:
>> +             st->cell_threshhigh =3D val;
>> +             break;
>> +     case AD7280A_CELL_UNDERVOLTAGE:
>> +             st->cell_threshlow =3D val;
>> +             break;
>> +     case AD7280A_AUX_ADC_OVERVOLTAGE:
>> +             st->aux_threshhigh =3D val;
>> +             break;
>> +     case AD7280A_AUX_ADC_UNDERVOLTAGE:
>> +             st->aux_threshlow =3D val;
>> +             break;
>> +     }
>> +
>> +     ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER,
>> +                        this_attr->address, 1, val);
>> +
>> +     mutex_unlock(&dev_info->mlock);
>> +
>> +     return ret ? ret : len;
>> +}
>> +
>> +static irqreturn_t ad7280_event_handler(int irq, void *private)
>> +{
>> +     struct iio_dev *dev_info =3D private;
>> +
>> +     iio_push_event(dev_info, 0,
>> +                    IIO_UNMOD_EVENT_CODE(IIO_IN,
>> +                                         0,
>> +                                         IIO_EV_TYPE_THRESH,
>> +                                         IIO_EV_DIR_EITHER),
>> +                    iio_get_time_ns());
> You have thresholds for temp and voltage below, but only voltage
> event. I wonder if the right thing here is to issue two events
> (subject to what is enabled).  If everything is turned on, there
> doesn't seem to be anyway to tell what happened.  If the event
> is consistent, I guess you could write a strobe function that would
> enable events up the chain and see when it kicked in. That would
> tell you where it came from.  No idea if one ever wants to know though.
Alternatively I could read all channels in the stack and compare
against the set thresholds. I think that would make the most sense here.

>
>> +
>> +     return IRQ_HANDLED;
>> +}
>> +
>> +static IIO_DEVICE_ATTR(in_thresh_low_value,
>> +                    S_IRUGO | S_IWUSR,
>> +                    ad7280_read_channel_config,
>> +                    ad7280_write_channel_config,
>> +                    AD7280A_CELL_UNDERVOLTAGE);
>> +
>> +static IIO_DEVICE_ATTR(in_thresh_high_value,
>> +                    S_IRUGO | S_IWUSR,
>> +                    ad7280_read_channel_config,
>> +                    ad7280_write_channel_config,
>> +                    AD7280A_CELL_OVERVOLTAGE);
>> +
>> +static IIO_DEVICE_ATTR(temp_thresh_low_value,
>> +                    S_IRUGO | S_IWUSR,
>> +                    ad7280_read_channel_config,
>> +                    ad7280_write_channel_config,
>> +                    AD7280A_AUX_ADC_UNDERVOLTAGE);
>> +
>> +static IIO_DEVICE_ATTR(temp_thresh_high_value,
>> +                    S_IRUGO | S_IWUSR,
>> +                    ad7280_read_channel_config,
>> +                    ad7280_write_channel_config,
>> +                    AD7280A_AUX_ADC_OVERVOLTAGE);
> These are shared over all channels?  Hmm. That's not a case
> I'd considered when writing the chan spec stuff for events,
> perhaps we need to allow for 'shared' events.  Technically
> the only abi meeting approach right now is to have these
> for every channel.  So write one channels threshold value
> then a read would tell you they have all changed.
Technically I could have different thresholds for any single
device in the chain, each featuring 6 cell and 6 temp/aux channels.

But in practice, you would set them to all being the same.
What prevents us from having the shared event thresholds?

>> +
>> +
>> +static struct attribute *ad7280_event_attributes[] =3D {
>> +&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
>> +&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
>> +&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
>> +&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
>> +     NULL,
>> +};
>> +
>> +static struct attribute_group ad7280_event_attrs_group =3D {
>> +     .attrs =3D ad7280_event_attributes,
>> +};
>> +
>> +static int ad7280_read_raw(struct iio_dev *dev_info,
>> +                        struct iio_chan_spec const *chan,
>> +                        int *val,
>> +                        int *val2,
>> +                        long m)
>> +{
>> +     struct ad7280_state *st =3D iio_priv(dev_info);
>> +     unsigned int scale_uv;
>> +     int ret;
>> +
>> +     switch (m) {
>> +     case 0:
>> +             mutex_lock(&dev_info->mlock);
>> +             switch (chan->type) {
>> +             case IIO_IN:
>> +                     ret =3D ad7280_read_channel(st, chan->address>> =
 8,
>> +                                               chan->address&  0xFF);
>> +                     break;
>> +             case IIO_IN_DIFF:
>> +                     ret =3D ad7280_read_all_channels(st, st->scan_cn=
t, NULL);
> Err... Really need some explanation for what this channel is!
Voltage across all cells.

>> +                     break;
>> +             default:
>> +                     ret =3D -EINVAL;
>> +             }
>> +             mutex_unlock(&dev_info->mlock);
>> +
>> +             if (ret<  0)
>> +                     return ret;
>> +
>> +             *val =3D ret;
>> +
>> +             return IIO_VAL_INT;
>> +     case (1<<  IIO_CHAN_INFO_SCALE_SHARED):
>> +             if ((chan->address&  0xFF)<=3D AD7280A_CELL_VOLTAGE_6)
>> +                     scale_uv =3D (4000 * 1000)>>  AD7280A_BITS;
>> +             else
>> +                     scale_uv =3D (5000 * 1000)>>  AD7280A_BITS;
>> +
>> +             *val =3D  scale_uv / 1000;
>> +             *val2 =3D (scale_uv % 1000) * 1000;
>> +             return IIO_VAL_INT_PLUS_MICRO;
>> +     }
>> +     return -EINVAL;
>> +}
>> +
>> +static const struct iio_info ad7280_info =3D {
>> +     .read_raw =3D&ad7280_read_raw,
>> +     .num_interrupt_lines =3D 1,
>> +     .event_attrs =3D&ad7280_event_attrs_group,
>> +     .attrs =3D&ad7280_attrs_group,
>> +     .driver_module =3D THIS_MODULE,
>> +};
>> +
>> +static struct ad7280_platform_data ad7793_default_pdata =3D {
>> +     .acquisition_time =3D AD7280A_ACQ_TIME_400ns,
>> +     .conversion_averaging =3D AD7280A_CONV_AVG_DIS,
>> +     .thermistor_term_en =3D true,
>> +};
> const?
ok
>> +
>> +static int __devinit ad7280_probe(struct spi_device *spi)
>> +{
>> +     struct ad7280_platform_data *pdata =3D spi->dev.platform_data;
>> +     struct ad7280_state *st;
>> +     int ret, regdone =3D 0;
>> +     const unsigned short tACQ_ns[4] =3D {465, 1010, 1460, 1890};
>> +     const unsigned short nAVG[4] =3D {1, 2, 4, 8};
>> +     struct iio_dev *indio_dev =3D iio_allocate_device(sizeof(*st));
>> +
>> +     if (indio_dev =3D=3D NULL)
>> +             return -ENOMEM;
>> +
>> +     st =3D iio_priv(indio_dev);
>> +     spi_set_drvdata(spi, indio_dev);
>> +     st->spi =3D spi;
>> +
>> +     if (!pdata)
>> +             pdata =3D&ad7793_default_pdata;
>> +
>> +     ad7280_crc8_build_table(st->crc_tab);
>> +
>> +     st->spi->max_speed_hz =3D AD7280A_MAX_SPI_CLK_Hz;
>> +     st->spi->mode =3D SPI_MODE_1;
>> +     spi_setup(st->spi);
>> +
>> +     st->ctrl_lb =3D AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time=
&  0x3);
>> +     st->ctrl_hb =3D AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_avera=
ging
>> +&  0x3) | (pdata->thermistor_term_en ?
>> +                     AD7280A_CTRL_LB_THERMISTOR_EN : 0);
>> +
>> +     ret =3D ad7280_chain_setup(st);
>> +     if (ret<  0)
>> +             goto error_free_device;
>> +
>> +     st->slave_num =3D ret;
>> +     st->scan_cnt =3D (st->slave_num + 1) * AD7280A_NUM_CH;
>> +     st->cell_threshhigh =3D 0xFF;
>> +     st->aux_threshhigh =3D 0xFF;
>> +
>> +     /*
>> +      * Total Conversion Time =3D ((tACQ + tCONV) *
>> +      *                         (Number of Conversions per Part)) =E2=
=88=92
>> +      *                         tACQ + ((N - 1) * tDELAY)
>> +      *
>> +      * Readback Delay =3D Total Conversion Time + tWAIT
>> +      */
>> +
>> +     st->readback_delay_us =3D
>> +             ((tACQ_ns[pdata->acquisition_time&  0x3] + 695) *
>> +             (AD7280A_NUM_CH * nAVG[pdata->conversion_averaging&  0x3=
]))
>> +             - tACQ_ns[pdata->acquisition_time&  0x3] +
>> +             st->slave_num * 250;
>> +
>> +     /* Convert to usecs */
>> +     st->readback_delay_us =3D DIV_ROUND_UP(st->readback_delay_us, 10=
00);
>> +     st->readback_delay_us +=3D 5; /* Add tWAIT */
>> +
>> +     indio_dev->name =3D spi_get_device_id(spi)->name;
>> +     indio_dev->dev.parent =3D&spi->dev;
>> +     indio_dev->modes =3D INDIO_DIRECT_MODE;
>> +
>> +     ret =3D ad7280_channel_init(st);
>> +     if (ret<  0)
>> +             goto error_free_device;
>> +
>> +     indio_dev->num_channels =3D ret;
>> +     indio_dev->channels =3D st->channels;
>> +     indio_dev->info =3D&ad7280_info;
>> +
>> +     ret =3D ad7280_attr_init(st);
>> +     if (ret<  0)
>> +             goto error_free_channels;
>> +
>> +     ret =3D iio_device_register(indio_dev);
>> +     if (ret)
>> +             goto error_free_attr;
>> +     regdone =3D 1;
>> +
>> +     if (spi->irq>  0) {
>> +             ret =3D ad7280_write(st, AD7280A_DEVADDR_MASTER,
>> +                                AD7280A_ALERT, 1,
>> +                                AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
>> +             if (ret)
>> +                     goto error_free_attr;
>> +
>> +             ret =3D ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
>> +                                AD7280A_ALERT, 0,
>> +                                AD7280A_ALERT_GEN_STATIC_HIGH |
>> +                                (pdata->chain_last_alert_ignore&  0xF=
));
>> +             if (ret)
>> +                     goto error_free_attr;
>> +
>> +             ret =3D request_threaded_irq(spi->irq,
>> +                                        NULL,
>> +                                        ad7280_event_handler,
>> +                                        IRQF_TRIGGER_FALLING |
>> +                                        IRQF_ONESHOT,
>> +                                        indio_dev->name,
>> +                                        indio_dev);
>> +             if (ret)
>> +                     goto error_free_attr;
>> +     }
>> +
>> +     return 0;
>> +
>> +error_free_attr:
>> +     kfree(st->iio_attr);
>> +
>> +error_free_channels:
>> +     kfree(st->channels);
>> +
>> +error_free_device:
>> +     if (regdone)
>> +             iio_device_unregister(indio_dev);
>> +     else
>> +             iio_free_device(indio_dev);
>> +
>> +     return ret;
>> +}
>> +
>> +static int __devexit ad7280_remove(struct spi_device *spi)
>> +{
>> +     struct iio_dev *indio_dev =3D spi_get_drvdata(spi);
>> +     struct ad7280_state *st =3D iio_priv(indio_dev);
>> +
>> +     if (spi->irq>  0)
>> +             free_irq(spi->irq, indio_dev);
>> +
>> +     ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
>> +                     AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
>> +
>> +     kfree(st->channels);
>> +     kfree(st->iio_attr);
>> +     iio_device_unregister(indio_dev);
>> +
>> +     return 0;
>> +}
>> +
>> +static const struct spi_device_id ad7280_id[] =3D {
>> +     {"ad7280a", 0},
>> +     {}
>> +};
>> +
>> +static struct spi_driver ad7280_driver =3D {
>> +     .driver =3D {
>> +             .name   =3D "ad7280",
>> +             .bus    =3D&spi_bus_type,
>> +             .owner  =3D THIS_MODULE,
>> +     },
>> +     .probe          =3D ad7280_probe,
>> +     .remove         =3D __devexit_p(ad7280_remove),
>> +     .id_table       =3D ad7280_id,
>> +};
>> +
>> +static int __init ad7280_init(void)
>> +{
>> +     return spi_register_driver(&ad7280_driver);
>> +}
>> +module_init(ad7280_init);
>> +
>> +static void __exit ad7280_exit(void)
>> +{
>> +     spi_unregister_driver(&ad7280_driver);
>> +}
>> +module_exit(ad7280_exit);
>> +
>> +MODULE_AUTHOR("Michael Hennerich<hennerich@blackfin.uclinux.org>");
>> +MODULE_DESCRIPTION("Analog Devices AD7280A");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/staging/iio/adc/ad7280a.h b/drivers/staging/iio/a=
dc/ad7280a.h
>> new file mode 100644
>> index 0000000..20400b0
>> --- /dev/null
>> +++ b/drivers/staging/iio/adc/ad7280a.h
>> @@ -0,0 +1,38 @@
>> +/*
>> + * AD7280A Lithium Ion Battery Monitoring System
>> + *
>> + * Copyright 2011 Analog Devices Inc.
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#ifndef IIO_ADC_AD7280_H_
>> +#define IIO_ADC_AD7280_H_
>> +
>> +/*
>> + * TODO: struct ad7280_platform_data needs to go into include/linux/i=
io
>> + */
>> +
>> +#define AD7280A_ACQ_TIME_400ns                       0
>> +#define AD7280A_ACQ_TIME_800ns                       1
>> +#define AD7280A_ACQ_TIME_1200ns                      2
>> +#define AD7280A_ACQ_TIME_1600ns                      3
>> +
>> +#define AD7280A_CONV_AVG_DIS                 0
>> +#define AD7280A_CONV_AVG_2                   1
>> +#define AD7280A_CONV_AVG_4                   2
>> +#define AD7280A_CONV_AVG_8                   3
>> +
>> +#define AD7280A_ALERT_REMOVE_VIN5            (1<<  2)
>> +#define AD7280A_ALERT_REMOVE_VIN4_VIN5               (2<<  2)
>> +#define AD7280A_ALERT_REMOVE_AUX5            (1<<  0)
>> +#define AD7280A_ALERT_REMOVE_AUX4_AUX5               (2<<  0)
>> +
>> +struct ad7280_platform_data {
>> +     unsigned acquisition_time;
>> +     unsigned conversion_averaging;
>> +     unsigned chain_last_alert_ignore;
>> +     bool thermistor_term_en;
>> +};
>> +
>> +#endif /* IIO_ADC_AD7280_H_ */
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

Thanks for the review.

--=20
Greetings,
Michael

--
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
Margaret Seif

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 12:48     ` Michael Hennerich
@ 2011-07-18 12:56       ` Jonathan Cameron
  2011-07-18 13:36         ` Michael Hennerich
  0 siblings, 1 reply; 13+ messages in thread
From: Jonathan Cameron @ 2011-07-18 12:56 UTC (permalink / raw)
  To: michael.hennerich
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

On 07/18/11 13:48, Michael Hennerich wrote:
> On 07/18/2011 01:43 PM, Jonathan Cameron wrote:
>> On 07/15/11 13:59, michael.hennerich@analog.com wrote:
>>> From: Michael Hennerich<michael.hennerich@analog.com>
>> Hi Michael, although anyone reading the datasheets will quickly
>> discover that this isn't a simple laptop style battery monitor,
>> it's probably worth making that clear in the patch title or
>> at very least here.
>>
>> Driver is pretty clear. Couple of nitpicks / queries inline.
>>
>> Thanks
>>
>> Jonathan
>>>
>>> Signed-off-by: Michael Hennerich<michael.hennerich@analog.com>
>>> ---
...
>>> +static irqreturn_t ad7280_event_handler(int irq, void *private)
>>> +{
>>> +     struct iio_dev *dev_info = private;
>>> +
>>> +     iio_push_event(dev_info, 0,
>>> +                    IIO_UNMOD_EVENT_CODE(IIO_IN,
>>> +                                         0,
>>> +                                         IIO_EV_TYPE_THRESH,
>>> +                                         IIO_EV_DIR_EITHER),
>>> +                    iio_get_time_ns());
>> You have thresholds for temp and voltage below, but only voltage
>> event. I wonder if the right thing here is to issue two events
>> (subject to what is enabled).  If everything is turned on, there
>> doesn't seem to be anyway to tell what happened.  If the event
>> is consistent, I guess you could write a strobe function that would
>> enable events up the chain and see when it kicked in. That would
>> tell you where it came from.  No idea if one ever wants to know though.
> Alternatively I could read all channels in the stack and compare
> against the set thresholds. I think that would make the most sense here.
Good point. That's much simpler.
> 
>>
>>> +
>>> +     return IRQ_HANDLED;
>>> +}
>>> +
>>> +static IIO_DEVICE_ATTR(in_thresh_low_value,
>>> +                    S_IRUGO | S_IWUSR,
>>> +                    ad7280_read_channel_config,
>>> +                    ad7280_write_channel_config,
>>> +                    AD7280A_CELL_UNDERVOLTAGE);
>>> +
>>> +static IIO_DEVICE_ATTR(in_thresh_high_value,
>>> +                    S_IRUGO | S_IWUSR,
>>> +                    ad7280_read_channel_config,
>>> +                    ad7280_write_channel_config,
>>> +                    AD7280A_CELL_OVERVOLTAGE);
>>> +
>>> +static IIO_DEVICE_ATTR(temp_thresh_low_value,
>>> +                    S_IRUGO | S_IWUSR,
>>> +                    ad7280_read_channel_config,
>>> +                    ad7280_write_channel_config,
>>> +                    AD7280A_AUX_ADC_UNDERVOLTAGE);
>>> +
>>> +static IIO_DEVICE_ATTR(temp_thresh_high_value,
>>> +                    S_IRUGO | S_IWUSR,
>>> +                    ad7280_read_channel_config,
>>> +                    ad7280_write_channel_config,
>>> +                    AD7280A_AUX_ADC_OVERVOLTAGE);
>> These are shared over all channels?  Hmm. That's not a case
>> I'd considered when writing the chan spec stuff for events,
>> perhaps we need to allow for 'shared' events.  Technically
>> the only abi meeting approach right now is to have these
>> for every channel.  So write one channels threshold value
>> then a read would tell you they have all changed.
> Technically I could have different thresholds for any single
> device in the chain, each featuring 6 cell and 6 temp/aux channels.
> 
> But in practice, you would set them to all being the same.
> What prevents us from having the shared event thresholds?
The difficulty in concisely specifying them in the chan spec
structures.  Good point though, it's fine abi wise.  Maybe
just leave these as you have them here for now and we can
think about how to concisely map them into the chan_spec
stuff at a later date..
> 
>>> +
>>> +
>>> +static struct attribute *ad7280_event_attributes[] = {
>>> +&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
>>> +&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
>>> +&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
>>> +&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
>>> +     NULL,
>>> +};
>>> +
>>> +static struct attribute_group ad7280_event_attrs_group = {
>>> +     .attrs = ad7280_event_attributes,
>>> +};
>>> +
>>> +static int ad7280_read_raw(struct iio_dev *dev_info,
>>> +                        struct iio_chan_spec const *chan,
>>> +                        int *val,
>>> +                        int *val2,
>>> +                        long m)
>>> +{
>>> +     struct ad7280_state *st = iio_priv(dev_info);
>>> +     unsigned int scale_uv;
>>> +     int ret;
>>> +
>>> +     switch (m) {
>>> +     case 0:
>>> +             mutex_lock(&dev_info->mlock);
>>> +             switch (chan->type) {
>>> +             case IIO_IN:
>>> +                     ret = ad7280_read_channel(st, chan->address>>  8,
>>> +                                               chan->address&  0xFF);
>>> +                     break;
>>> +             case IIO_IN_DIFF:
>>> +                     ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
>> Err... Really need some explanation for what this channel is!
> Voltage across all cells.
Fair enough. So are the other voltages not differential as well? (across a given
cell rather than referred to a base voltage)
...

>>> +
>>> +#endif /* IIO_ADC_AD7280_H_ */
>> -- 
>> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
> 
> Thanks for the review.
> 
You are welcome.



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 12:56       ` Jonathan Cameron
@ 2011-07-18 13:36         ` Michael Hennerich
  2011-07-18 13:41           ` Jonathan Cameron
  2011-07-18 15:06           ` Michael Hennerich
  0 siblings, 2 replies; 13+ messages in thread
From: Michael Hennerich @ 2011-07-18 13:36 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

On 07/18/2011 02:56 PM, Jonathan Cameron wrote:
> On 07/18/11 13:48, Michael Hennerich wrote:
>> On 07/18/2011 01:43 PM, Jonathan Cameron wrote:
>>> On 07/15/11 13:59, michael.hennerich@analog.com wrote:
>>>> From: Michael Hennerich<michael.hennerich@analog.com>
>>> Hi Michael, although anyone reading the datasheets will quickly
>>> discover that this isn't a simple laptop style battery monitor,
>>> it's probably worth making that clear in the patch title or
>>> at very least here.
>>>
>>> Driver is pretty clear. Couple of nitpicks / queries inline.
>>>
>>> Thanks
>>>
>>> Jonathan
>>>> Signed-off-by: Michael Hennerich<michael.hennerich@analog.com>
>>>> ---
> ...
>>>> +static irqreturn_t ad7280_event_handler(int irq, void *private)
>>>> +{
>>>> +     struct iio_dev *dev_info = private;
>>>> +
>>>> +     iio_push_event(dev_info, 0,
>>>> +                    IIO_UNMOD_EVENT_CODE(IIO_IN,
>>>> +                                         0,
>>>> +                                         IIO_EV_TYPE_THRESH,
>>>> +                                         IIO_EV_DIR_EITHER),
>>>> +                    iio_get_time_ns());
>>> You have thresholds for temp and voltage below, but only voltage
>>> event. I wonder if the right thing here is to issue two events
>>> (subject to what is enabled).  If everything is turned on, there
>>> doesn't seem to be anyway to tell what happened.  If the event
>>> is consistent, I guess you could write a strobe function that would
>>> enable events up the chain and see when it kicked in. That would
>>> tell you where it came from.  No idea if one ever wants to know though.
>> Alternatively I could read all channels in the stack and compare
>> against the set thresholds. I think that would make the most sense here.
> Good point. That's much simpler.
>>>> +
>>>> +     return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +static IIO_DEVICE_ATTR(in_thresh_low_value,
>>>> +                    S_IRUGO | S_IWUSR,
>>>> +                    ad7280_read_channel_config,
>>>> +                    ad7280_write_channel_config,
>>>> +                    AD7280A_CELL_UNDERVOLTAGE);
>>>> +
>>>> +static IIO_DEVICE_ATTR(in_thresh_high_value,
>>>> +                    S_IRUGO | S_IWUSR,
>>>> +                    ad7280_read_channel_config,
>>>> +                    ad7280_write_channel_config,
>>>> +                    AD7280A_CELL_OVERVOLTAGE);
>>>> +
>>>> +static IIO_DEVICE_ATTR(temp_thresh_low_value,
>>>> +                    S_IRUGO | S_IWUSR,
>>>> +                    ad7280_read_channel_config,
>>>> +                    ad7280_write_channel_config,
>>>> +                    AD7280A_AUX_ADC_UNDERVOLTAGE);
>>>> +
>>>> +static IIO_DEVICE_ATTR(temp_thresh_high_value,
>>>> +                    S_IRUGO | S_IWUSR,
>>>> +                    ad7280_read_channel_config,
>>>> +                    ad7280_write_channel_config,
>>>> +                    AD7280A_AUX_ADC_OVERVOLTAGE);
>>> These are shared over all channels?  Hmm. That's not a case
>>> I'd considered when writing the chan spec stuff for events,
>>> perhaps we need to allow for 'shared' events.  Technically
>>> the only abi meeting approach right now is to have these
>>> for every channel.  So write one channels threshold value
>>> then a read would tell you they have all changed.
>> Technically I could have different thresholds for any single
>> device in the chain, each featuring 6 cell and 6 temp/aux channels.
>>
>> But in practice, you would set them to all being the same.
>> What prevents us from having the shared event thresholds?
> The difficulty in concisely specifying them in the chan spec
> structures.  Good point though, it's fine abi wise.  Maybe
> just leave these as you have them here for now and we can
> think about how to concisely map them into the chan_spec
> stuff at a later date..
>>>> +
>>>> +
>>>> +static struct attribute *ad7280_event_attributes[] = {
>>>> +&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
>>>> +&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
>>>> +&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
>>>> +&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
>>>> +     NULL,
>>>> +};
>>>> +
>>>> +static struct attribute_group ad7280_event_attrs_group = {
>>>> +     .attrs = ad7280_event_attributes,
>>>> +};
>>>> +
>>>> +static int ad7280_read_raw(struct iio_dev *dev_info,
>>>> +                        struct iio_chan_spec const *chan,
>>>> +                        int *val,
>>>> +                        int *val2,
>>>> +                        long m)
>>>> +{
>>>> +     struct ad7280_state *st = iio_priv(dev_info);
>>>> +     unsigned int scale_uv;
>>>> +     int ret;
>>>> +
>>>> +     switch (m) {
>>>> +     case 0:
>>>> +             mutex_lock(&dev_info->mlock);
>>>> +             switch (chan->type) {
>>>> +             case IIO_IN:
>>>> +                     ret = ad7280_read_channel(st, chan->address>>   8,
>>>> +                                               chan->address&   0xFF);
>>>> +                     break;
>>>> +             case IIO_IN_DIFF:
>>>> +                     ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
>>> Err... Really need some explanation for what this channel is!
>> Voltage across all cells.
> Fair enough. So are the other voltages not differential as well? (across a given
> cell rather than referred to a base voltage)
> ...
Yes technically seen they are all differential.

>>>> +
>>>> +#endif /* IIO_ADC_AD7280_H_ */
>>> -- 
>>> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>
>> Thanks for the review.
>>
> You are welcome.
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


-- 
Greetings,
Michael

--
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
Margaret Seif

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 13:36         ` Michael Hennerich
@ 2011-07-18 13:41           ` Jonathan Cameron
  2011-07-18 13:47             ` Michael Hennerich
  2011-07-18 15:06           ` Michael Hennerich
  1 sibling, 1 reply; 13+ messages in thread
From: Jonathan Cameron @ 2011-07-18 13:41 UTC (permalink / raw)
  To: michael.hennerich
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers


>>>>> +
>>>>> +static int ad7280_read_raw(struct iio_dev *dev_info,
>>>>> +                        struct iio_chan_spec const *chan,
>>>>> +                        int *val,
>>>>> +                        int *val2,
>>>>> +                        long m)
>>>>> +{
>>>>> +     struct ad7280_state *st = iio_priv(dev_info);
>>>>> +     unsigned int scale_uv;
>>>>> +     int ret;
>>>>> +
>>>>> +     switch (m) {
>>>>> +     case 0:
>>>>> +             mutex_lock(&dev_info->mlock);
>>>>> +             switch (chan->type) {
>>>>> +             case IIO_IN:
>>>>> +                     ret = ad7280_read_channel(st, chan->address>>   8,
>>>>> +                                               chan->address&   0xFF);
>>>>> +                     break;
>>>>> +             case IIO_IN_DIFF:
>>>>> +                     ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
>>>> Err... Really need some explanation for what this channel is!
>>> Voltage across all cells.
>> Fair enough. So are the other voltages not differential as well? (across a given
>> cell rather than referred to a base voltage)
>> ...
> Yes technically seen they are all differential.
> 
Any cost in setting them up as such then?

in1-in0
in2-in1 etc
+
inX-in0 for your summed one?


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 13:41           ` Jonathan Cameron
@ 2011-07-18 13:47             ` Michael Hennerich
  0 siblings, 0 replies; 13+ messages in thread
From: Michael Hennerich @ 2011-07-18 13:47 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

On 07/18/2011 03:41 PM, Jonathan Cameron wrote:
>>>>>> +
>>>>>> +static int ad7280_read_raw(struct iio_dev *dev_info,
>>>>>> +                        struct iio_chan_spec const *chan,
>>>>>> +                        int *val,
>>>>>> +                        int *val2,
>>>>>> +                        long m)
>>>>>> +{
>>>>>> +     struct ad7280_state *st = iio_priv(dev_info);
>>>>>> +     unsigned int scale_uv;
>>>>>> +     int ret;
>>>>>> +
>>>>>> +     switch (m) {
>>>>>> +     case 0:
>>>>>> +             mutex_lock(&dev_info->mlock);
>>>>>> +             switch (chan->type) {
>>>>>> +             case IIO_IN:
>>>>>> +                     ret = ad7280_read_channel(st, chan->address>>    8,
>>>>>> +                                               chan->address&    0xFF);
>>>>>> +                     break;
>>>>>> +             case IIO_IN_DIFF:
>>>>>> +                     ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
>>>>> Err... Really need some explanation for what this channel is!
>>>> Voltage across all cells.
>>> Fair enough. So are the other voltages not differential as well? (across a given
>>> cell rather than referred to a base voltage)
>>> ...
>> Yes technically seen they are all differential.
>>
> Any cost in setting them up as such then?
>
> in1-in0
> in2-in1 etc
> +
> inX-in0 for your summed one?
Yes this is already on my to-do list...
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


-- 
Greetings,
Michael

--
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
Margaret Seif

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 13:36         ` Michael Hennerich
  2011-07-18 13:41           ` Jonathan Cameron
@ 2011-07-18 15:06           ` Michael Hennerich
  2011-07-18 15:12             ` Jonathan Cameron
  1 sibling, 1 reply; 13+ messages in thread
From: Michael Hennerich @ 2011-07-18 15:06 UTC (permalink / raw)
  To: Hennerich, Michael
  Cc: Jonathan Cameron, linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

On 07/18/2011 03:36 PM, Michael Hennerich wrote:
> On 07/18/2011 02:56 PM, Jonathan Cameron wrote:
>> On 07/18/11 13:48, Michael Hennerich wrote:
>>> On 07/18/2011 01:43 PM, Jonathan Cameron wrote:
>>>> On 07/15/11 13:59, michael.hennerich@analog.com wrote:
>>>>
>> ...
>>>>> +static irqreturn_t ad7280_event_handler(int irq, void *private)
>>>>> +{
>>>>> +     struct iio_dev *dev_info = private;
>>>>> +
>>>>> +     iio_push_event(dev_info, 0,
>>>>> +                    IIO_UNMOD_EVENT_CODE(IIO_IN,
>>>>> +                                         0,
>>>>> +                                         IIO_EV_TYPE_THRESH,
>>>>> +                                         IIO_EV_DIR_EITHER),
>>>>> +                    iio_get_time_ns());
>>>> You have thresholds for temp and voltage below, but only voltage
>>>> event. I wonder if the right thing here is to issue two events
>>>> (subject to what is enabled).  If everything is turned on, there
>>>> doesn't seem to be anyway to tell what happened.  If the event
>>>> is consistent, I guess you could write a strobe function that would
>>>> enable events up the chain and see when it kicked in. That would
>>>> tell you where it came from.  No idea if one ever wants to know though.
>>> Alternatively I could read all channels in the stack and compare
>>> against the set thresholds. I think that would make the most sense here.
>> Good point. That's much simpler.
>>
Actually - I remember why I didn't do that in the first place.
The bits reserved in IIO_EVENT_CODE for the number are not enough.


-- 
Greetings,
Michael

--
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
Margaret Seif



^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-18 15:06           ` Michael Hennerich
@ 2011-07-18 15:12             ` Jonathan Cameron
  0 siblings, 0 replies; 13+ messages in thread
From: Jonathan Cameron @ 2011-07-18 15:12 UTC (permalink / raw)
  To: michael.hennerich
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

On 07/18/11 16:06, Michael Hennerich wrote:
> On 07/18/2011 03:36 PM, Michael Hennerich wrote:
>> On 07/18/2011 02:56 PM, Jonathan Cameron wrote:
>>> On 07/18/11 13:48, Michael Hennerich wrote:
>>>> On 07/18/2011 01:43 PM, Jonathan Cameron wrote:
>>>>> On 07/15/11 13:59, michael.hennerich@analog.com wrote:
>>>>>
>>> ...
>>>>>> +static irqreturn_t ad7280_event_handler(int irq, void *private)
>>>>>> +{
>>>>>> +     struct iio_dev *dev_info = private;
>>>>>> +
>>>>>> +     iio_push_event(dev_info, 0,
>>>>>> +                    IIO_UNMOD_EVENT_CODE(IIO_IN,
>>>>>> +                                         0,
>>>>>> +                                         IIO_EV_TYPE_THRESH,
>>>>>> +                                         IIO_EV_DIR_EITHER),
>>>>>> +                    iio_get_time_ns());
>>>>> You have thresholds for temp and voltage below, but only voltage
>>>>> event. I wonder if the right thing here is to issue two events
>>>>> (subject to what is enabled).  If everything is turned on, there
>>>>> doesn't seem to be anyway to tell what happened.  If the event
>>>>> is consistent, I guess you could write a strobe function that would
>>>>> enable events up the chain and see when it kicked in. That would
>>>>> tell you where it came from.  No idea if one ever wants to know though.
>>>> Alternatively I could read all channels in the stack and compare
>>>> against the set thresholds. I think that would make the most sense here.
>>> Good point. That's much simpler.
>>>
> Actually - I remember why I didn't do that in the first place.
> The bits reserved in IIO_EVENT_CODE for the number are not enough.
Fair enough.  Then we need to fix that.  What is the maximum number you need?

^ permalink raw reply	[flat|nested] 13+ messages in thread

* [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-20 13:03 michael.hennerich
@ 2011-07-20 13:03 ` michael.hennerich
  2011-07-20 13:03 ` michael.hennerich
  1 sibling, 0 replies; 13+ messages in thread
From: michael.hennerich @ 2011-07-20 13:03 UTC (permalink / raw)
  To: greg; +Cc: linux-iio, device-drivers-devel, drivers, jic23,
	Michael Hennerich

From: Michael Hennerich <michael.hennerich@analog.com>

The AD7280A monitoring system contains all the functions required for
general purpose monitoring and maintenance of stacked
lithium ion batteries as used in hybrid electric vehicles,
battery backup applications, etc.

Changes since V1:

Make cell channels all type IIO_IN_DIFF, update documentation accordingly.
Remove unused and redundant defines.
Use SI units where applicable.
Remove unnecessary wrapper function.
Remove redundant initialization.
Add comments where requested.
Revise event handler.
Use const where applicable.

Changes since V2:

Remove redundant adc.h include file, scheduled for removal.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
---
 .../iio/Documentation/sysfs-bus-iio-adc-ad7280a    |   21 +
 drivers/staging/iio/adc/Kconfig                    |   10 +
 drivers/staging/iio/adc/Makefile                   |    1 +
 drivers/staging/iio/adc/ad7280a.c                  |  992 ++++++++++++++++++++
 drivers/staging/iio/adc/ad7280a.h                  |   38 +
 5 files changed, 1062 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
 create mode 100644 drivers/staging/iio/adc/ad7280a.c
 create mode 100644 drivers/staging/iio/adc/ad7280a.h

diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
new file mode 100644
index 0000000..863d385
--- /dev/null
+++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
@@ -0,0 +1,21 @@
+What:		/sys/bus/iio/devices/deviceX/inY-inZ_balance_switch_en
+KernelVersion:	3.0.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Writing 1 enables the cell balance output switch corresponding
+		to input Y. Writing 0 disables it. If the inY-inZ_balance_timer
+		is set to a none zero value, the corresponding switch will
+		enable for the programmed amount of time, before it
+		automatically disables.
+
+What:		/sys/bus/iio/devices/deviceX/inY-inZ_balance_timer
+KernelVersion:	3.0.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		The inY-inZ_balance_timer file allows the user to program
+		individual times for each cell balance output. The AD7280A
+		allows the user to set the timer to a value from 0 minutes to
+		36.9 minutes. The resolution of the timer is 71.5 sec.
+		The value written is the on-time in milliseconds. When the
+		timer value is set 0, the timer is disabled. The cell balance
+		outputs are controlled only by inY-inZ_balance_switch_en.
diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index b39f2e1..60de7d7 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -182,6 +182,16 @@ config ADT7410
 	  Say yes here to build support for Analog Devices ADT7410
 	  temperature sensors.

+config AD7280
+	tristate "Analog Devices AD7280A Lithium Ion Battery Monitoring System"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices AD7280A
+	  Lithium Ion Battery Monitoring System.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad7280a
+
 config MAX1363
 	tristate "Maxim max1363 ADC driver"
 	depends on I2C
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index f020351..634a55f 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -40,3 +40,4 @@ obj-$(CONFIG_AD7816) += ad7816.o
 obj-$(CONFIG_ADT75) += adt75.o
 obj-$(CONFIG_ADT7310) += adt7310.o
 obj-$(CONFIG_ADT7410) += adt7410.o
+obj-$(CONFIG_AD7280) += ad7280a.o
diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
new file mode 100644
index 0000000..ab6cf9c
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -0,0 +1,992 @@
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+#include "ad7280a.h"
+
+/* Registers */
+#define AD7280A_CELL_VOLTAGE_1		0x0  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_2		0x1  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_3		0x2  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_4		0x3  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_5		0x4  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_6		0x5  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_1		0x6  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_2		0x7  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_3		0x8  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_4		0x9  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_5		0xA  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_6		0xB  /* D11 to D0, Read only */
+#define AD7280A_SELF_TEST		0xC  /* D11 to D0, Read only */
+#define AD7280A_CONTROL_HB		0xD  /* D15 to D8, Read/write */
+#define AD7280A_CONTROL_LB		0xE  /* D7 to D0, Read/write */
+#define AD7280A_CELL_OVERVOLTAGE	0xF  /* D7 to D0, Read/write */
+#define AD7280A_CELL_UNDERVOLTAGE	0x10 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_OVERVOLTAGE	0x11 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_UNDERVOLTAGE	0x12 /* D7 to D0, Read/write */
+#define AD7280A_ALERT			0x13 /* D7 to D0, Read/write */
+#define AD7280A_CELL_BALANCE		0x14 /* D7 to D0, Read/write */
+#define AD7280A_CB1_TIMER		0x15 /* D7 to D0, Read/write */
+#define AD7280A_CB2_TIMER		0x16 /* D7 to D0, Read/write */
+#define AD7280A_CB3_TIMER		0x17 /* D7 to D0, Read/write */
+#define AD7280A_CB4_TIMER		0x18 /* D7 to D0, Read/write */
+#define AD7280A_CB5_TIMER		0x19 /* D7 to D0, Read/write */
+#define AD7280A_CB6_TIMER		0x1A /* D7 to D0, Read/write */
+#define AD7280A_PD_TIMER		0x1B /* D7 to D0, Read/write */
+#define AD7280A_READ			0x1C /* D7 to D0, Read/write */
+#define AD7280A_CNVST_CONTROL		0x1D /* D7 to D0, Read/write */
+
+/* Bits and Masks */
+#define AD7280A_CTRL_HB_CONV_INPUT_ALL			(0 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4	(1 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL		(2 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST		(3 << 6)
+#define AD7280A_CTRL_HB_CONV_RES_READ_ALL		(0 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4	(1 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL		(2 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_NO		(3 << 4)
+#define AD7280A_CTRL_HB_CONV_START_CNVST		(0 << 3)
+#define AD7280A_CTRL_HB_CONV_START_CS			(1 << 3)
+#define AD7280A_CTRL_HB_CONV_AVG_DIS			(0 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_2			(1 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_4			(2 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_8			(3 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG(x)			((x) << 1)
+#define AD7280A_CTRL_HB_PWRDN_SW			(1 << 0)
+
+#define AD7280A_CTRL_LB_SWRST				(1 << 7)
+#define AD7280A_CTRL_LB_ACQ_TIME_400ns			(0 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_800ns			(1 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1200ns			(2 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1600ns			(3 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME(x)			((x) << 5)
+#define AD7280A_CTRL_LB_MUST_SET			(1 << 4)
+#define AD7280A_CTRL_LB_THERMISTOR_EN			(1 << 3)
+#define AD7280A_CTRL_LB_LOCK_DEV_ADDR			(1 << 2)
+#define AD7280A_CTRL_LB_INC_DEV_ADDR			(1 << 1)
+#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN		(1 << 0)
+
+#define AD7280A_ALERT_GEN_STATIC_HIGH			(1 << 6)
+#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN		(3 << 6)
+
+#define AD7280A_ALL_CELLS				(0xAD << 16)
+
+#define AD7280A_MAX_SPI_CLK_Hz		700000 /* < 1MHz */
+#define AD7280A_MAX_CHAIN		8
+#define AD7280A_CELLS_PER_DEV		6
+#define AD7280A_BITS			12
+#define AD7280A_NUM_CH			(AD7280A_AUX_ADC_6 - \
+					AD7280A_CELL_VOLTAGE_1 + 1)
+
+#define AD7280A_DEVADDR_MASTER		0
+#define AD7280A_DEVADDR_ALL		0x1F
+/* 5-bit device address is sent LSB first */
+#define AD7280A_DEVADDR(addr)	(((addr & 0x1) << 4) | ((addr & 0x2) << 3) | \
+				(addr & 0x4) | ((addr & 0x8) >> 3) | \
+				((addr & 0x10) >> 4))
+
+/* During a read a valid write is mandatory.
+ * So writing to the highest available address (Address 0x1F)
+ * and setting the address all parts bit to 0 is recommended
+ * So the TXVAL is AD7280A_DEVADDR_ALL + CRC
+ */
+#define AD7280A_READ_TXVAL	0xF800030A
+
+/*
+ * AD7280 CRC
+ *
+ * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F
+ */
+#define POLYNOM		0x2F
+#define POLYNOM_ORDER	8
+#define HIGHBIT		1 << (POLYNOM_ORDER - 1);
+
+struct ad7280_state {
+	struct spi_device		*spi;
+	struct iio_chan_spec		*channels;
+	struct iio_dev_attr		*iio_attr;
+	int				slave_num;
+	int				scan_cnt;
+	int				readback_delay_us;
+	unsigned char			crc_tab[256];
+	unsigned char			ctrl_hb;
+	unsigned char			ctrl_lb;
+	unsigned char			cell_threshhigh;
+	unsigned char			cell_threshlow;
+	unsigned char			aux_threshhigh;
+	unsigned char			aux_threshlow;
+	unsigned char			cb_mask[AD7280A_MAX_CHAIN];
+};
+
+static void ad7280_crc8_build_table(unsigned char *crc_tab)
+{
+	unsigned char bit, crc;
+	int cnt, i;
+
+	for (cnt = 0; cnt < 256; cnt++) {
+		crc = cnt;
+		for (i = 0; i < 8; i++) {
+			bit = crc & HIGHBIT;
+			crc <<= 1;
+			if (bit)
+				crc ^= POLYNOM;
+		}
+		crc_tab[cnt] = crc;
+	}
+}
+
+static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned val)
+{
+	unsigned char crc;
+
+	crc = crc_tab[val >> 16 & 0xFF];
+	crc = crc_tab[crc ^ (val >> 8 & 0xFF)];
+
+	return  crc ^ (val & 0xFF);
+}
+
+static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
+{
+	unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);
+
+	if (crc != ((val >> 2) & 0xFF))
+		return -EIO;
+
+	return 0;
+}
+
+/* After initiating a conversion sequence we need to wait until the
+ * conversion is done. The delay is typically in the range of 15..30 us
+ * however depending an the number of devices in the daisy chain and the
+ * number of averages taken, conversion delays and acquisition time options
+ * it may take up to 250us, in this case we better sleep instead of busy
+ * wait.
+ */
+
+static void ad7280_delay(struct ad7280_state *st)
+{
+	if (st->readback_delay_us < 50)
+		udelay(st->readback_delay_us);
+	else
+		msleep(1);
+}
+
+static int __ad7280_read32(struct spi_device *spi, unsigned *val)
+{
+	unsigned rx_buf, tx_buf = cpu_to_be32(AD7280A_READ_TXVAL);
+	int ret;
+
+	struct spi_transfer t = {
+		.tx_buf	= &tx_buf,
+		.rx_buf = &rx_buf,
+		.len = 4,
+	};
+	struct spi_message m;
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t, &m);
+
+	ret = spi_sync(spi, &m);
+	if (ret)
+		return ret;
+
+	*val = be32_to_cpu(rx_buf);
+
+	return 0;
+}
+
+static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
+			unsigned addr, bool all, unsigned val)
+{
+	unsigned reg = (devaddr << 27 | addr << 21 |
+			(val & 0xFF) << 13 | all << 12);
+
+	reg |= ad7280_calc_crc8(st->crc_tab, reg >> 11) << 3 | 0x2;
+	reg = cpu_to_be32(reg);
+
+	return spi_write(st->spi, &reg, 4);
+}
+
+static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
+			unsigned addr)
+{
+	int ret;
+	unsigned tmp;
+
+	/* turns off the read operation on all parts */
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_NO |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	/* turns on the read operation on the addressed part */
+	ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	/* Set register address on the part to be read from */
+	ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+	if (ret)
+		return ret;
+
+	__ad7280_read32(st->spi, &tmp);
+
+	if (ad7280_check_crc(st, tmp))
+		return -EIO;
+
+	if (((tmp >> 27) != devaddr) || (((tmp >> 21) & 0x3F) != addr))
+		return -EFAULT;
+
+	return (tmp >> 13) & 0xFF;
+}
+
+static int ad7280_read_channel(struct ad7280_state *st, unsigned devaddr,
+			       unsigned addr)
+{
+	int ret;
+	unsigned tmp;
+
+	ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_NO |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			AD7280A_CTRL_HB_CONV_START_CS |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ad7280_delay(st);
+
+	__ad7280_read32(st->spi, &tmp);
+
+	if (ad7280_check_crc(st, tmp))
+		return -EIO;
+
+	if (((tmp >> 27) != devaddr) || (((tmp >> 23) & 0xF) != addr))
+		return -EFAULT;
+
+	return (tmp >> 11) & 0xFFF;
+}
+
+static int ad7280_read_all_channels(struct ad7280_state *st, unsigned cnt,
+			     unsigned *array)
+{
+	int i, ret;
+	unsigned tmp, sum = 0;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+			   AD7280A_CELL_VOLTAGE_1 << 2);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			AD7280A_CTRL_HB_CONV_START_CS |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ad7280_delay(st);
+
+	for (i = 0; i < cnt; i++) {
+		__ad7280_read32(st->spi, &tmp);
+
+		if (ad7280_check_crc(st, tmp))
+			return -EIO;
+
+		if (array)
+			array[i] = tmp;
+		/* only sum cell voltages */
+		if (((tmp >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6)
+			sum += ((tmp >> 11) & 0xFFF);
+	}
+
+	return sum;
+}
+
+static int ad7280_chain_setup(struct ad7280_state *st)
+{
+	unsigned val, n;
+	int ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+			AD7280A_CTRL_LB_MUST_SET |
+			AD7280A_CTRL_LB_SWRST |
+			st->ctrl_lb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+			AD7280A_CTRL_LB_MUST_SET |
+			st->ctrl_lb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+			AD7280A_CONTROL_LB << 2);
+	if (ret)
+		return ret;
+
+	for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
+		__ad7280_read32(st->spi, &val);
+		if (val == 0)
+			return n - 1;
+
+		if (ad7280_check_crc(st, val))
+			return -EIO;
+
+		if (n != AD7280A_DEVADDR(val >> 27))
+			return -EIO;
+	}
+
+	return -EFAULT;
+}
+
+static ssize_t ad7280_show_balance_sw(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	return sprintf(buf, "%d\n",
+		       !!(st->cb_mask[this_attr->address >> 8] &
+		       (1 << ((this_attr->address & 0xFF) + 2))));
+}
+
+static ssize_t ad7280_store_balance_sw(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	bool readin;
+	int ret;
+	unsigned devaddr, ch;
+
+	ret = strtobool(buf, &readin);
+	if (ret)
+		return ret;
+
+	devaddr = this_attr->address >> 8;
+	ch = this_attr->address & 0xFF;
+
+	mutex_lock(&dev_info->mlock);
+	if (readin)
+		st->cb_mask[devaddr] |= 1 << (ch + 2);
+	else
+		st->cb_mask[devaddr] &= ~(1 << (ch + 2));
+
+	ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
+			   0, st->cb_mask[devaddr]);
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static ssize_t ad7280_show_balance_timer(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	int ret;
+	unsigned msecs;
+
+	mutex_lock(&dev_info->mlock);
+	ret = ad7280_read(st, this_attr->address >> 8,
+			this_attr->address & 0xFF);
+	mutex_unlock(&dev_info->mlock);
+
+	if (ret < 0)
+		return ret;
+
+	msecs = (ret >> 3) * 71500;
+
+	return sprintf(buf, "%d\n", msecs);
+}
+
+static ssize_t ad7280_store_balance_timer(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	long val;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	val /= 71500;
+
+	if (val > 31)
+		return -EINVAL;
+
+	mutex_lock(&dev_info->mlock);
+	ret = ad7280_write(st, this_attr->address >> 8,
+			   this_attr->address & 0xFF,
+			   0, (val & 0x1F) << 3);
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
+					   AD7280A_CELLS_PER_DEV * 2 + 1];
+
+static struct attribute_group ad7280_attrs_group = {
+	.attrs = ad7280_attributes,
+};
+
+static int ad7280_channel_init(struct ad7280_state *st)
+{
+	int dev, ch, cnt;
+
+	st->channels = kzalloc(sizeof(*st->channels) *
+				((st->slave_num + 1) * 12 + 2), GFP_KERNEL);
+	if (st->channels == NULL)
+		return -ENOMEM;
+
+	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_AUX_ADC_6; ch++,
+			cnt++) {
+			if (ch < AD7280A_AUX_ADC_1) {
+				st->channels[cnt].type = IIO_IN_DIFF;
+				st->channels[cnt].channel = (dev * 6) + ch;
+				st->channels[cnt].channel2 =
+					st->channels[cnt].channel + 1;
+			} else {
+				st->channels[cnt].type = IIO_TEMP;
+				st->channels[cnt].channel = (dev * 6) + ch - 6;
+			}
+			st->channels[cnt].indexed = 1;
+			st->channels[cnt].info_mask =
+				(1 << IIO_CHAN_INFO_SCALE_SHARED);
+			st->channels[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 | ch;
+			st->channels[cnt].scan_index = cnt;
+			st->channels[cnt].scan_type.sign = 'u';
+			st->channels[cnt].scan_type.realbits = 12;
+			st->channels[cnt].scan_type.storagebits = 32;
+			st->channels[cnt].scan_type.shift = 0;
+		}
+
+	st->channels[cnt].type = IIO_IN_DIFF;
+	st->channels[cnt].channel = 0;
+	st->channels[cnt].channel2 = dev * 6;
+	st->channels[cnt].address = AD7280A_ALL_CELLS;
+	st->channels[cnt].indexed = 1;
+	st->channels[cnt].info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED);
+	st->channels[cnt].scan_index = cnt;
+	st->channels[cnt].scan_type.sign = 'u';
+	st->channels[cnt].scan_type.realbits = 32;
+	st->channels[cnt].scan_type.storagebits = 32;
+	st->channels[cnt].scan_type.shift = 0;
+	cnt++;
+	st->channels[cnt].type = IIO_TIMESTAMP;
+	st->channels[cnt].channel = -1;
+	st->channels[cnt].scan_index = cnt;
+	st->channels[cnt].scan_type.sign = 's';
+	st->channels[cnt].scan_type.realbits = 64;
+	st->channels[cnt].scan_type.storagebits = 64;
+	st->channels[cnt].scan_type.shift = 0;
+
+	return cnt + 1;
+}
+
+static int ad7280_attr_init(struct ad7280_state *st)
+{
+	int dev, ch, cnt;
+
+	st->iio_attr = kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1) *
+				AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
+	if (st->iio_attr == NULL)
+		return -ENOMEM;
+
+	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;
+			ch++, cnt++) {
+			st->iio_attr[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 | ch;
+			st->iio_attr[cnt].dev_attr.attr.mode =
+				S_IWUSR | S_IRUGO;
+			st->iio_attr[cnt].dev_attr.show =
+				ad7280_show_balance_sw;
+			st->iio_attr[cnt].dev_attr.store =
+				ad7280_store_balance_sw;
+			st->iio_attr[cnt].dev_attr.attr.name =
+				kasprintf(GFP_KERNEL,
+					"in%d-in%d_balance_switch_en",
+					(dev * AD7280A_CELLS_PER_DEV) + ch,
+					(dev * AD7280A_CELLS_PER_DEV) + ch + 1);
+			ad7280_attributes[cnt] =
+				&st->iio_attr[cnt].dev_attr.attr;
+			cnt++;
+			st->iio_attr[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 |
+				(AD7280A_CB1_TIMER + ch);
+			st->iio_attr[cnt].dev_attr.attr.mode =
+				S_IWUSR | S_IRUGO;
+			st->iio_attr[cnt].dev_attr.show =
+				ad7280_show_balance_timer;
+			st->iio_attr[cnt].dev_attr.store =
+				ad7280_store_balance_timer;
+			st->iio_attr[cnt].dev_attr.attr.name =
+				kasprintf(GFP_KERNEL, "in%d-in%d_balance_timer",
+					(dev * AD7280A_CELLS_PER_DEV) + ch,
+					(dev * AD7280A_CELLS_PER_DEV) + ch + 1);
+			ad7280_attributes[cnt] =
+				&st->iio_attr[cnt].dev_attr.attr;
+		}
+
+	ad7280_attributes[cnt] = NULL;
+
+	return 0;
+}
+
+static ssize_t ad7280_read_channel_config(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	unsigned val;
+
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+		val = 1000 + (st->cell_threshhigh * 1568) / 100;
+		break;
+	case AD7280A_CELL_UNDERVOLTAGE:
+		val = 1000 + (st->cell_threshlow * 1568) / 100;
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+		val = (st->aux_threshhigh * 196) / 10;
+		break;
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		val = (st->aux_threshlow * 196) / 10;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t ad7280_write_channel_config(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	long val;
+	int ret;
+
+	ret = strict_strtol(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+	case AD7280A_CELL_UNDERVOLTAGE:
+		val = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		val = (val * 10) / 196; /* LSB 19.6mV */
+		break;
+	default:
+		return -EFAULT;
+	}
+
+	val = clamp(val, 0L, 0xFFL);
+
+	mutex_lock(&dev_info->mlock);
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+		st->cell_threshhigh = val;
+		break;
+	case AD7280A_CELL_UNDERVOLTAGE:
+		st->cell_threshlow = val;
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+		st->aux_threshhigh = val;
+		break;
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		st->aux_threshlow = val;
+		break;
+	}
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+			   this_attr->address, 1, val);
+
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static irqreturn_t ad7280_event_handler(int irq, void *private)
+{
+	struct iio_dev *dev_info = private;
+	struct ad7280_state *st = iio_priv(dev_info);
+	unsigned *channels;
+	int i, ret;
+
+	channels = kzalloc(sizeof(*channels) * st->scan_cnt, GFP_KERNEL);
+	if (channels == NULL)
+		return IRQ_HANDLED;
+
+	ret = ad7280_read_all_channels(st, st->scan_cnt, channels);
+	if (ret < 0)
+		return IRQ_HANDLED;
+
+	for (i = 0; i < st->scan_cnt; i++) {
+		if (((channels[i] >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6) {
+			if (((channels[i] >> 11) & 0xFFF) >=
+				st->cell_threshhigh)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_IN_DIFF,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_RISING),
+					iio_get_time_ns());
+			else if (((channels[i] >> 11) & 0xFFF) <=
+				st->cell_threshlow)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_IN_DIFF,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_FALLING),
+					iio_get_time_ns());
+		} else {
+			if (((channels[i] >> 11) & 0xFFF) >= st->aux_threshhigh)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_RISING),
+					iio_get_time_ns());
+			else if (((channels[i] >> 11) & 0xFFF) <=
+				st->aux_threshlow)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_FALLING),
+					iio_get_time_ns());
+		}
+	}
+
+	kfree(channels);
+
+	return IRQ_HANDLED;
+}
+
+static IIO_DEVICE_ATTR_NAMED(in_thresh_low_value,
+		in-in_thresh_low_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_CELL_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR_NAMED(in_thresh_high_value,
+		in-in_thresh_high_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_CELL_OVERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_low_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_AUX_ADC_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_high_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_AUX_ADC_OVERVOLTAGE);
+
+
+static struct attribute *ad7280_event_attributes[] = {
+	&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
+	&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
+	&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
+	&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
+	NULL,
+};
+
+static struct attribute_group ad7280_event_attrs_group = {
+	.attrs = ad7280_event_attributes,
+};
+
+static int ad7280_read_raw(struct iio_dev *dev_info,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad7280_state *st = iio_priv(dev_info);
+	unsigned int scale_uv;
+	int ret;
+
+	switch (m) {
+	case 0:
+		mutex_lock(&dev_info->mlock);
+		if (chan->address == AD7280A_ALL_CELLS)
+			ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
+		else
+			ret = ad7280_read_channel(st, chan->address >> 8,
+						  chan->address & 0xFF);
+		mutex_unlock(&dev_info->mlock);
+
+		if (ret < 0)
+			return ret;
+
+		*val = ret;
+
+		return IIO_VAL_INT;
+	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+		if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6)
+			scale_uv = (4000 * 1000) >> AD7280A_BITS;
+		else
+			scale_uv = (5000 * 1000) >> AD7280A_BITS;
+
+		*val =  scale_uv / 1000;
+		*val2 = (scale_uv % 1000) * 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+	return -EINVAL;
+}
+
+static const struct iio_info ad7280_info = {
+	.read_raw = &ad7280_read_raw,
+	.num_interrupt_lines = 1,
+	.event_attrs = &ad7280_event_attrs_group,
+	.attrs = &ad7280_attrs_group,
+	.driver_module = THIS_MODULE,
+};
+
+static const struct ad7280_platform_data ad7793_default_pdata = {
+	.acquisition_time = AD7280A_ACQ_TIME_400ns,
+	.conversion_averaging = AD7280A_CONV_AVG_DIS,
+	.thermistor_term_en = true,
+};
+
+static int __devinit ad7280_probe(struct spi_device *spi)
+{
+	const struct ad7280_platform_data *pdata = spi->dev.platform_data;
+	struct ad7280_state *st;
+	int ret, regdone = 0;
+	const unsigned short tACQ_ns[4] = {465, 1010, 1460, 1890};
+	const unsigned short nAVG[4] = {1, 2, 4, 8};
+	struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
+
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	spi_set_drvdata(spi, indio_dev);
+	st->spi = spi;
+
+	if (!pdata)
+		pdata = &ad7793_default_pdata;
+
+	ad7280_crc8_build_table(st->crc_tab);
+
+	st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_Hz;
+	st->spi->mode = SPI_MODE_1;
+	spi_setup(st->spi);
+
+	st->ctrl_lb = AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & 0x3);
+	st->ctrl_hb = AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averaging
+			& 0x3) | (pdata->thermistor_term_en ?
+			AD7280A_CTRL_LB_THERMISTOR_EN : 0);
+
+	ret = ad7280_chain_setup(st);
+	if (ret < 0)
+		goto error_free_device;
+
+	st->slave_num = ret;
+	st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
+	st->cell_threshhigh = 0xFF;
+	st->aux_threshhigh = 0xFF;
+
+	/*
+	 * Total Conversion Time = ((tACQ + tCONV) *
+	 *			   (Number of Conversions per Part)) −
+	 *			   tACQ + ((N - 1) * tDELAY)
+	 *
+	 * Readback Delay = Total Conversion Time + tWAIT
+	 */
+
+	st->readback_delay_us =
+		((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
+		(AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
+		- tACQ_ns[pdata->acquisition_time & 0x3] +
+		st->slave_num * 250;
+
+	/* Convert to usecs */
+	st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);
+	st->readback_delay_us += 5; /* Add tWAIT */
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = ad7280_channel_init(st);
+	if (ret < 0)
+		goto error_free_device;
+
+	indio_dev->num_channels = ret;
+	indio_dev->channels = st->channels;
+	indio_dev->info = &ad7280_info;
+
+	ret = ad7280_attr_init(st);
+	if (ret < 0)
+		goto error_free_channels;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_free_attr;
+	regdone = 1;
+
+	if (spi->irq > 0) {
+		ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+				   AD7280A_ALERT, 1,
+				   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
+		if (ret)
+			goto error_free_attr;
+
+		ret = ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
+				   AD7280A_ALERT, 0,
+				   AD7280A_ALERT_GEN_STATIC_HIGH |
+				   (pdata->chain_last_alert_ignore & 0xF));
+		if (ret)
+			goto error_free_attr;
+
+		ret = request_threaded_irq(spi->irq,
+					   NULL,
+					   ad7280_event_handler,
+					   IRQF_TRIGGER_FALLING |
+					   IRQF_ONESHOT,
+					   indio_dev->name,
+					   indio_dev);
+		if (ret)
+			goto error_free_attr;
+	}
+
+	return 0;
+
+error_free_attr:
+	kfree(st->iio_attr);
+
+error_free_channels:
+	kfree(st->channels);
+
+error_free_device:
+	if (regdone)
+		iio_device_unregister(indio_dev);
+	else
+		iio_free_device(indio_dev);
+
+	return ret;
+}
+
+static int __devexit ad7280_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ad7280_state *st = iio_priv(indio_dev);
+
+	if (spi->irq > 0)
+		free_irq(spi->irq, indio_dev);
+
+	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
+
+	kfree(st->channels);
+	kfree(st->iio_attr);
+	iio_device_unregister(indio_dev);
+
+	return 0;
+}
+
+static const struct spi_device_id ad7280_id[] = {
+	{"ad7280a", 0},
+	{}
+};
+
+static struct spi_driver ad7280_driver = {
+	.driver = {
+		.name	= "ad7280",
+		.bus	= &spi_bus_type,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ad7280_probe,
+	.remove		= __devexit_p(ad7280_remove),
+	.id_table	= ad7280_id,
+};
+
+static int __init ad7280_init(void)
+{
+	return spi_register_driver(&ad7280_driver);
+}
+module_init(ad7280_init);
+
+static void __exit ad7280_exit(void)
+{
+	spi_unregister_driver(&ad7280_driver);
+}
+module_exit(ad7280_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7280A");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/iio/adc/ad7280a.h b/drivers/staging/iio/adc/ad7280a.h
new file mode 100644
index 0000000..20400b0
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7280a.h
@@ -0,0 +1,38 @@
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_ADC_AD7280_H_
+#define IIO_ADC_AD7280_H_
+
+/*
+ * TODO: struct ad7280_platform_data needs to go into include/linux/iio
+ */
+
+#define AD7280A_ACQ_TIME_400ns			0
+#define AD7280A_ACQ_TIME_800ns			1
+#define AD7280A_ACQ_TIME_1200ns			2
+#define AD7280A_ACQ_TIME_1600ns			3
+
+#define AD7280A_CONV_AVG_DIS			0
+#define AD7280A_CONV_AVG_2			1
+#define AD7280A_CONV_AVG_4			2
+#define AD7280A_CONV_AVG_8			3
+
+#define AD7280A_ALERT_REMOVE_VIN5		(1 << 2)
+#define AD7280A_ALERT_REMOVE_VIN4_VIN5		(2 << 2)
+#define AD7280A_ALERT_REMOVE_AUX5		(1 << 0)
+#define AD7280A_ALERT_REMOVE_AUX4_AUX5		(2 << 0)
+
+struct ad7280_platform_data {
+	unsigned acquisition_time;
+	unsigned conversion_averaging;
+	unsigned chain_last_alert_ignore;
+	bool thermistor_term_en;
+};
+
+#endif /* IIO_ADC_AD7280_H_ */
--
1.7.0.4

^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System
  2011-07-20 13:03 michael.hennerich
  2011-07-20 13:03 ` [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System michael.hennerich
@ 2011-07-20 13:03 ` michael.hennerich
  1 sibling, 0 replies; 13+ messages in thread
From: michael.hennerich @ 2011-07-20 13:03 UTC (permalink / raw)
  To: greg; +Cc: linux-iio, device-drivers-devel, drivers, jic23,
	Michael Hennerich

From: Michael Hennerich <michael.hennerich@analog.com>

The AD7280A monitoring system contains all the functions required for
general purpose monitoring and maintenance of stacked
lithium ion batteries as used in hybrid electric vehicles,
battery backup applications, etc.

Changes since V1:

Make cell channels all type IIO_IN_DIFF, update documentation accordingly.
Remove unused and redundant defines.
Use SI units where applicable.
Remove unnecessary wrapper function.
Remove redundant initialization.
Add comments where requested.
Revise event handler.
Use const where applicable.

Changes since V2:

Remove redundant adc.h include file, scheduled for removal.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
---
 .../iio/Documentation/sysfs-bus-iio-adc-ad7280a    |   21 +
 drivers/staging/iio/adc/Kconfig                    |   10 +
 drivers/staging/iio/adc/Makefile                   |    1 +
 drivers/staging/iio/adc/ad7280a.c                  |  992 ++++++++++++++++++++
 drivers/staging/iio/adc/ad7280a.h                  |   38 +
 5 files changed, 1062 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
 create mode 100644 drivers/staging/iio/adc/ad7280a.c
 create mode 100644 drivers/staging/iio/adc/ad7280a.h

diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
new file mode 100644
index 0000000..863d385
--- /dev/null
+++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-adc-ad7280a
@@ -0,0 +1,21 @@
+What:		/sys/bus/iio/devices/deviceX/inY-inZ_balance_switch_en
+KernelVersion:	3.0.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Writing 1 enables the cell balance output switch corresponding
+		to input Y. Writing 0 disables it. If the inY-inZ_balance_timer
+		is set to a none zero value, the corresponding switch will
+		enable for the programmed amount of time, before it
+		automatically disables.
+
+What:		/sys/bus/iio/devices/deviceX/inY-inZ_balance_timer
+KernelVersion:	3.0.0
+Contact:	linux-iio@vger.kernel.org
+Description:
+		The inY-inZ_balance_timer file allows the user to program
+		individual times for each cell balance output. The AD7280A
+		allows the user to set the timer to a value from 0 minutes to
+		36.9 minutes. The resolution of the timer is 71.5 sec.
+		The value written is the on-time in milliseconds. When the
+		timer value is set 0, the timer is disabled. The cell balance
+		outputs are controlled only by inY-inZ_balance_switch_en.
diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index b39f2e1..60de7d7 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -182,6 +182,16 @@ config ADT7410
 	  Say yes here to build support for Analog Devices ADT7410
 	  temperature sensors.
 
+config AD7280
+	tristate "Analog Devices AD7280A Lithium Ion Battery Monitoring System"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices AD7280A
+	  Lithium Ion Battery Monitoring System.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad7280a
+
 config MAX1363
 	tristate "Maxim max1363 ADC driver"
 	depends on I2C
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index f020351..634a55f 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -40,3 +40,4 @@ obj-$(CONFIG_AD7816) += ad7816.o
 obj-$(CONFIG_ADT75) += adt75.o
 obj-$(CONFIG_ADT7310) += adt7310.o
 obj-$(CONFIG_ADT7410) += adt7410.o
+obj-$(CONFIG_AD7280) += ad7280a.o
diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
new file mode 100644
index 0000000..ab6cf9c
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -0,0 +1,992 @@
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+#include "ad7280a.h"
+
+/* Registers */
+#define AD7280A_CELL_VOLTAGE_1		0x0  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_2		0x1  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_3		0x2  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_4		0x3  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_5		0x4  /* D11 to D0, Read only */
+#define AD7280A_CELL_VOLTAGE_6		0x5  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_1		0x6  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_2		0x7  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_3		0x8  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_4		0x9  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_5		0xA  /* D11 to D0, Read only */
+#define AD7280A_AUX_ADC_6		0xB  /* D11 to D0, Read only */
+#define AD7280A_SELF_TEST		0xC  /* D11 to D0, Read only */
+#define AD7280A_CONTROL_HB		0xD  /* D15 to D8, Read/write */
+#define AD7280A_CONTROL_LB		0xE  /* D7 to D0, Read/write */
+#define AD7280A_CELL_OVERVOLTAGE	0xF  /* D7 to D0, Read/write */
+#define AD7280A_CELL_UNDERVOLTAGE	0x10 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_OVERVOLTAGE	0x11 /* D7 to D0, Read/write */
+#define AD7280A_AUX_ADC_UNDERVOLTAGE	0x12 /* D7 to D0, Read/write */
+#define AD7280A_ALERT			0x13 /* D7 to D0, Read/write */
+#define AD7280A_CELL_BALANCE		0x14 /* D7 to D0, Read/write */
+#define AD7280A_CB1_TIMER		0x15 /* D7 to D0, Read/write */
+#define AD7280A_CB2_TIMER		0x16 /* D7 to D0, Read/write */
+#define AD7280A_CB3_TIMER		0x17 /* D7 to D0, Read/write */
+#define AD7280A_CB4_TIMER		0x18 /* D7 to D0, Read/write */
+#define AD7280A_CB5_TIMER		0x19 /* D7 to D0, Read/write */
+#define AD7280A_CB6_TIMER		0x1A /* D7 to D0, Read/write */
+#define AD7280A_PD_TIMER		0x1B /* D7 to D0, Read/write */
+#define AD7280A_READ			0x1C /* D7 to D0, Read/write */
+#define AD7280A_CNVST_CONTROL		0x1D /* D7 to D0, Read/write */
+
+/* Bits and Masks */
+#define AD7280A_CTRL_HB_CONV_INPUT_ALL			(0 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4	(1 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_6CELL		(2 << 6)
+#define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST		(3 << 6)
+#define AD7280A_CTRL_HB_CONV_RES_READ_ALL		(0 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4	(1 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_6CELL		(2 << 4)
+#define AD7280A_CTRL_HB_CONV_RES_READ_NO		(3 << 4)
+#define AD7280A_CTRL_HB_CONV_START_CNVST		(0 << 3)
+#define AD7280A_CTRL_HB_CONV_START_CS			(1 << 3)
+#define AD7280A_CTRL_HB_CONV_AVG_DIS			(0 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_2			(1 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_4			(2 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG_8			(3 << 1)
+#define AD7280A_CTRL_HB_CONV_AVG(x)			((x) << 1)
+#define AD7280A_CTRL_HB_PWRDN_SW			(1 << 0)
+
+#define AD7280A_CTRL_LB_SWRST				(1 << 7)
+#define AD7280A_CTRL_LB_ACQ_TIME_400ns			(0 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_800ns			(1 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1200ns			(2 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME_1600ns			(3 << 5)
+#define AD7280A_CTRL_LB_ACQ_TIME(x)			((x) << 5)
+#define AD7280A_CTRL_LB_MUST_SET			(1 << 4)
+#define AD7280A_CTRL_LB_THERMISTOR_EN			(1 << 3)
+#define AD7280A_CTRL_LB_LOCK_DEV_ADDR			(1 << 2)
+#define AD7280A_CTRL_LB_INC_DEV_ADDR			(1 << 1)
+#define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN		(1 << 0)
+
+#define AD7280A_ALERT_GEN_STATIC_HIGH			(1 << 6)
+#define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN		(3 << 6)
+
+#define AD7280A_ALL_CELLS				(0xAD << 16)
+
+#define AD7280A_MAX_SPI_CLK_Hz		700000 /* < 1MHz */
+#define AD7280A_MAX_CHAIN		8
+#define AD7280A_CELLS_PER_DEV		6
+#define AD7280A_BITS			12
+#define AD7280A_NUM_CH			(AD7280A_AUX_ADC_6 - \
+					AD7280A_CELL_VOLTAGE_1 + 1)
+
+#define AD7280A_DEVADDR_MASTER		0
+#define AD7280A_DEVADDR_ALL		0x1F
+/* 5-bit device address is sent LSB first */
+#define AD7280A_DEVADDR(addr)	(((addr & 0x1) << 4) | ((addr & 0x2) << 3) | \
+				(addr & 0x4) | ((addr & 0x8) >> 3) | \
+				((addr & 0x10) >> 4))
+
+/* During a read a valid write is mandatory.
+ * So writing to the highest available address (Address 0x1F)
+ * and setting the address all parts bit to 0 is recommended
+ * So the TXVAL is AD7280A_DEVADDR_ALL + CRC
+ */
+#define AD7280A_READ_TXVAL	0xF800030A
+
+/*
+ * AD7280 CRC
+ *
+ * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F
+ */
+#define POLYNOM		0x2F
+#define POLYNOM_ORDER	8
+#define HIGHBIT		1 << (POLYNOM_ORDER - 1);
+
+struct ad7280_state {
+	struct spi_device		*spi;
+	struct iio_chan_spec		*channels;
+	struct iio_dev_attr		*iio_attr;
+	int				slave_num;
+	int				scan_cnt;
+	int				readback_delay_us;
+	unsigned char			crc_tab[256];
+	unsigned char			ctrl_hb;
+	unsigned char			ctrl_lb;
+	unsigned char			cell_threshhigh;
+	unsigned char			cell_threshlow;
+	unsigned char			aux_threshhigh;
+	unsigned char			aux_threshlow;
+	unsigned char			cb_mask[AD7280A_MAX_CHAIN];
+};
+
+static void ad7280_crc8_build_table(unsigned char *crc_tab)
+{
+	unsigned char bit, crc;
+	int cnt, i;
+
+	for (cnt = 0; cnt < 256; cnt++) {
+		crc = cnt;
+		for (i = 0; i < 8; i++) {
+			bit = crc & HIGHBIT;
+			crc <<= 1;
+			if (bit)
+				crc ^= POLYNOM;
+		}
+		crc_tab[cnt] = crc;
+	}
+}
+
+static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned val)
+{
+	unsigned char crc;
+
+	crc = crc_tab[val >> 16 & 0xFF];
+	crc = crc_tab[crc ^ (val >> 8 & 0xFF)];
+
+	return  crc ^ (val & 0xFF);
+}
+
+static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
+{
+	unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);
+
+	if (crc != ((val >> 2) & 0xFF))
+		return -EIO;
+
+	return 0;
+}
+
+/* After initiating a conversion sequence we need to wait until the
+ * conversion is done. The delay is typically in the range of 15..30 us
+ * however depending an the number of devices in the daisy chain and the
+ * number of averages taken, conversion delays and acquisition time options
+ * it may take up to 250us, in this case we better sleep instead of busy
+ * wait.
+ */
+
+static void ad7280_delay(struct ad7280_state *st)
+{
+	if (st->readback_delay_us < 50)
+		udelay(st->readback_delay_us);
+	else
+		msleep(1);
+}
+
+static int __ad7280_read32(struct spi_device *spi, unsigned *val)
+{
+	unsigned rx_buf, tx_buf = cpu_to_be32(AD7280A_READ_TXVAL);
+	int ret;
+
+	struct spi_transfer t = {
+		.tx_buf	= &tx_buf,
+		.rx_buf = &rx_buf,
+		.len = 4,
+	};
+	struct spi_message m;
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t, &m);
+
+	ret = spi_sync(spi, &m);
+	if (ret)
+		return ret;
+
+	*val = be32_to_cpu(rx_buf);
+
+	return 0;
+}
+
+static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
+			unsigned addr, bool all, unsigned val)
+{
+	unsigned reg = (devaddr << 27 | addr << 21 |
+			(val & 0xFF) << 13 | all << 12);
+
+	reg |= ad7280_calc_crc8(st->crc_tab, reg >> 11) << 3 | 0x2;
+	reg = cpu_to_be32(reg);
+
+	return spi_write(st->spi, &reg, 4);
+}
+
+static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
+			unsigned addr)
+{
+	int ret;
+	unsigned tmp;
+
+	/* turns off the read operation on all parts */
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_NO |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	/* turns on the read operation on the addressed part */
+	ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	/* Set register address on the part to be read from */
+	ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+	if (ret)
+		return ret;
+
+	__ad7280_read32(st->spi, &tmp);
+
+	if (ad7280_check_crc(st, tmp))
+		return -EIO;
+
+	if (((tmp >> 27) != devaddr) || (((tmp >> 21) & 0x3F) != addr))
+		return -EFAULT;
+
+	return (tmp >> 13) & 0xFF;
+}
+
+static int ad7280_read_channel(struct ad7280_state *st, unsigned devaddr,
+			       unsigned addr)
+{
+	int ret;
+	unsigned tmp;
+
+	ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_NO |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			AD7280A_CTRL_HB_CONV_START_CS |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ad7280_delay(st);
+
+	__ad7280_read32(st->spi, &tmp);
+
+	if (ad7280_check_crc(st, tmp))
+		return -EIO;
+
+	if (((tmp >> 27) != devaddr) || (((tmp >> 23) & 0xF) != addr))
+		return -EFAULT;
+
+	return (tmp >> 11) & 0xFFF;
+}
+
+static int ad7280_read_all_channels(struct ad7280_state *st, unsigned cnt,
+			     unsigned *array)
+{
+	int i, ret;
+	unsigned tmp, sum = 0;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+			   AD7280A_CELL_VOLTAGE_1 << 2);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_CONV_INPUT_ALL |
+			AD7280A_CTRL_HB_CONV_RES_READ_ALL |
+			AD7280A_CTRL_HB_CONV_START_CS |
+			st->ctrl_hb);
+	if (ret)
+		return ret;
+
+	ad7280_delay(st);
+
+	for (i = 0; i < cnt; i++) {
+		__ad7280_read32(st->spi, &tmp);
+
+		if (ad7280_check_crc(st, tmp))
+			return -EIO;
+
+		if (array)
+			array[i] = tmp;
+		/* only sum cell voltages */
+		if (((tmp >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6)
+			sum += ((tmp >> 11) & 0xFFF);
+	}
+
+	return sum;
+}
+
+static int ad7280_chain_setup(struct ad7280_state *st)
+{
+	unsigned val, n;
+	int ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+			AD7280A_CTRL_LB_MUST_SET |
+			AD7280A_CTRL_LB_SWRST |
+			st->ctrl_lb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
+			AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
+			AD7280A_CTRL_LB_LOCK_DEV_ADDR |
+			AD7280A_CTRL_LB_MUST_SET |
+			st->ctrl_lb);
+	if (ret)
+		return ret;
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
+			AD7280A_CONTROL_LB << 2);
+	if (ret)
+		return ret;
+
+	for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
+		__ad7280_read32(st->spi, &val);
+		if (val == 0)
+			return n - 1;
+
+		if (ad7280_check_crc(st, val))
+			return -EIO;
+
+		if (n != AD7280A_DEVADDR(val >> 27))
+			return -EIO;
+	}
+
+	return -EFAULT;
+}
+
+static ssize_t ad7280_show_balance_sw(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	return sprintf(buf, "%d\n",
+		       !!(st->cb_mask[this_attr->address >> 8] &
+		       (1 << ((this_attr->address & 0xFF) + 2))));
+}
+
+static ssize_t ad7280_store_balance_sw(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	bool readin;
+	int ret;
+	unsigned devaddr, ch;
+
+	ret = strtobool(buf, &readin);
+	if (ret)
+		return ret;
+
+	devaddr = this_attr->address >> 8;
+	ch = this_attr->address & 0xFF;
+
+	mutex_lock(&dev_info->mlock);
+	if (readin)
+		st->cb_mask[devaddr] |= 1 << (ch + 2);
+	else
+		st->cb_mask[devaddr] &= ~(1 << (ch + 2));
+
+	ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
+			   0, st->cb_mask[devaddr]);
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static ssize_t ad7280_show_balance_timer(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	int ret;
+	unsigned msecs;
+
+	mutex_lock(&dev_info->mlock);
+	ret = ad7280_read(st, this_attr->address >> 8,
+			this_attr->address & 0xFF);
+	mutex_unlock(&dev_info->mlock);
+
+	if (ret < 0)
+		return ret;
+
+	msecs = (ret >> 3) * 71500;
+
+	return sprintf(buf, "%d\n", msecs);
+}
+
+static ssize_t ad7280_store_balance_timer(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	long val;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	val /= 71500;
+
+	if (val > 31)
+		return -EINVAL;
+
+	mutex_lock(&dev_info->mlock);
+	ret = ad7280_write(st, this_attr->address >> 8,
+			   this_attr->address & 0xFF,
+			   0, (val & 0x1F) << 3);
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
+					   AD7280A_CELLS_PER_DEV * 2 + 1];
+
+static struct attribute_group ad7280_attrs_group = {
+	.attrs = ad7280_attributes,
+};
+
+static int ad7280_channel_init(struct ad7280_state *st)
+{
+	int dev, ch, cnt;
+
+	st->channels = kzalloc(sizeof(*st->channels) *
+				((st->slave_num + 1) * 12 + 2), GFP_KERNEL);
+	if (st->channels == NULL)
+		return -ENOMEM;
+
+	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_AUX_ADC_6; ch++,
+			cnt++) {
+			if (ch < AD7280A_AUX_ADC_1) {
+				st->channels[cnt].type = IIO_IN_DIFF;
+				st->channels[cnt].channel = (dev * 6) + ch;
+				st->channels[cnt].channel2 =
+					st->channels[cnt].channel + 1;
+			} else {
+				st->channels[cnt].type = IIO_TEMP;
+				st->channels[cnt].channel = (dev * 6) + ch - 6;
+			}
+			st->channels[cnt].indexed = 1;
+			st->channels[cnt].info_mask =
+				(1 << IIO_CHAN_INFO_SCALE_SHARED);
+			st->channels[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 | ch;
+			st->channels[cnt].scan_index = cnt;
+			st->channels[cnt].scan_type.sign = 'u';
+			st->channels[cnt].scan_type.realbits = 12;
+			st->channels[cnt].scan_type.storagebits = 32;
+			st->channels[cnt].scan_type.shift = 0;
+		}
+
+	st->channels[cnt].type = IIO_IN_DIFF;
+	st->channels[cnt].channel = 0;
+	st->channels[cnt].channel2 = dev * 6;
+	st->channels[cnt].address = AD7280A_ALL_CELLS;
+	st->channels[cnt].indexed = 1;
+	st->channels[cnt].info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED);
+	st->channels[cnt].scan_index = cnt;
+	st->channels[cnt].scan_type.sign = 'u';
+	st->channels[cnt].scan_type.realbits = 32;
+	st->channels[cnt].scan_type.storagebits = 32;
+	st->channels[cnt].scan_type.shift = 0;
+	cnt++;
+	st->channels[cnt].type = IIO_TIMESTAMP;
+	st->channels[cnt].channel = -1;
+	st->channels[cnt].scan_index = cnt;
+	st->channels[cnt].scan_type.sign = 's';
+	st->channels[cnt].scan_type.realbits = 64;
+	st->channels[cnt].scan_type.storagebits = 64;
+	st->channels[cnt].scan_type.shift = 0;
+
+	return cnt + 1;
+}
+
+static int ad7280_attr_init(struct ad7280_state *st)
+{
+	int dev, ch, cnt;
+
+	st->iio_attr = kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1) *
+				AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
+	if (st->iio_attr == NULL)
+		return -ENOMEM;
+
+	for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
+		for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;
+			ch++, cnt++) {
+			st->iio_attr[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 | ch;
+			st->iio_attr[cnt].dev_attr.attr.mode =
+				S_IWUSR | S_IRUGO;
+			st->iio_attr[cnt].dev_attr.show =
+				ad7280_show_balance_sw;
+			st->iio_attr[cnt].dev_attr.store =
+				ad7280_store_balance_sw;
+			st->iio_attr[cnt].dev_attr.attr.name =
+				kasprintf(GFP_KERNEL,
+					"in%d-in%d_balance_switch_en",
+					(dev * AD7280A_CELLS_PER_DEV) + ch,
+					(dev * AD7280A_CELLS_PER_DEV) + ch + 1);
+			ad7280_attributes[cnt] =
+				&st->iio_attr[cnt].dev_attr.attr;
+			cnt++;
+			st->iio_attr[cnt].address =
+				AD7280A_DEVADDR(dev) << 8 |
+				(AD7280A_CB1_TIMER + ch);
+			st->iio_attr[cnt].dev_attr.attr.mode =
+				S_IWUSR | S_IRUGO;
+			st->iio_attr[cnt].dev_attr.show =
+				ad7280_show_balance_timer;
+			st->iio_attr[cnt].dev_attr.store =
+				ad7280_store_balance_timer;
+			st->iio_attr[cnt].dev_attr.attr.name =
+				kasprintf(GFP_KERNEL, "in%d-in%d_balance_timer",
+					(dev * AD7280A_CELLS_PER_DEV) + ch,
+					(dev * AD7280A_CELLS_PER_DEV) + ch + 1);
+			ad7280_attributes[cnt] =
+				&st->iio_attr[cnt].dev_attr.attr;
+		}
+
+	ad7280_attributes[cnt] = NULL;
+
+	return 0;
+}
+
+static ssize_t ad7280_read_channel_config(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	unsigned val;
+
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+		val = 1000 + (st->cell_threshhigh * 1568) / 100;
+		break;
+	case AD7280A_CELL_UNDERVOLTAGE:
+		val = 1000 + (st->cell_threshlow * 1568) / 100;
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+		val = (st->aux_threshhigh * 196) / 10;
+		break;
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		val = (st->aux_threshlow * 196) / 10;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t ad7280_write_channel_config(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7280_state *st = iio_priv(dev_info);
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	long val;
+	int ret;
+
+	ret = strict_strtol(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+	case AD7280A_CELL_UNDERVOLTAGE:
+		val = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		val = (val * 10) / 196; /* LSB 19.6mV */
+		break;
+	default:
+		return -EFAULT;
+	}
+
+	val = clamp(val, 0L, 0xFFL);
+
+	mutex_lock(&dev_info->mlock);
+	switch (this_attr->address) {
+	case AD7280A_CELL_OVERVOLTAGE:
+		st->cell_threshhigh = val;
+		break;
+	case AD7280A_CELL_UNDERVOLTAGE:
+		st->cell_threshlow = val;
+		break;
+	case AD7280A_AUX_ADC_OVERVOLTAGE:
+		st->aux_threshhigh = val;
+		break;
+	case AD7280A_AUX_ADC_UNDERVOLTAGE:
+		st->aux_threshlow = val;
+		break;
+	}
+
+	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+			   this_attr->address, 1, val);
+
+	mutex_unlock(&dev_info->mlock);
+
+	return ret ? ret : len;
+}
+
+static irqreturn_t ad7280_event_handler(int irq, void *private)
+{
+	struct iio_dev *dev_info = private;
+	struct ad7280_state *st = iio_priv(dev_info);
+	unsigned *channels;
+	int i, ret;
+
+	channels = kzalloc(sizeof(*channels) * st->scan_cnt, GFP_KERNEL);
+	if (channels == NULL)
+		return IRQ_HANDLED;
+
+	ret = ad7280_read_all_channels(st, st->scan_cnt, channels);
+	if (ret < 0)
+		return IRQ_HANDLED;
+
+	for (i = 0; i < st->scan_cnt; i++) {
+		if (((channels[i] >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6) {
+			if (((channels[i] >> 11) & 0xFFF) >=
+				st->cell_threshhigh)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_IN_DIFF,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_RISING),
+					iio_get_time_ns());
+			else if (((channels[i] >> 11) & 0xFFF) <=
+				st->cell_threshlow)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_IN_DIFF,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_FALLING),
+					iio_get_time_ns());
+		} else {
+			if (((channels[i] >> 11) & 0xFFF) >= st->aux_threshhigh)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_RISING),
+					iio_get_time_ns());
+			else if (((channels[i] >> 11) & 0xFFF) <=
+				st->aux_threshlow)
+				iio_push_event(dev_info, 0,
+					IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+					0,
+					IIO_EV_TYPE_THRESH,
+					IIO_EV_DIR_FALLING),
+					iio_get_time_ns());
+		}
+	}
+
+	kfree(channels);
+
+	return IRQ_HANDLED;
+}
+
+static IIO_DEVICE_ATTR_NAMED(in_thresh_low_value,
+		in-in_thresh_low_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_CELL_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR_NAMED(in_thresh_high_value,
+		in-in_thresh_high_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_CELL_OVERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_low_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_AUX_ADC_UNDERVOLTAGE);
+
+static IIO_DEVICE_ATTR(temp_thresh_high_value,
+		S_IRUGO | S_IWUSR,
+		ad7280_read_channel_config,
+		ad7280_write_channel_config,
+		AD7280A_AUX_ADC_OVERVOLTAGE);
+
+
+static struct attribute *ad7280_event_attributes[] = {
+	&iio_dev_attr_in_thresh_low_value.dev_attr.attr,
+	&iio_dev_attr_in_thresh_high_value.dev_attr.attr,
+	&iio_dev_attr_temp_thresh_low_value.dev_attr.attr,
+	&iio_dev_attr_temp_thresh_high_value.dev_attr.attr,
+	NULL,
+};
+
+static struct attribute_group ad7280_event_attrs_group = {
+	.attrs = ad7280_event_attributes,
+};
+
+static int ad7280_read_raw(struct iio_dev *dev_info,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad7280_state *st = iio_priv(dev_info);
+	unsigned int scale_uv;
+	int ret;
+
+	switch (m) {
+	case 0:
+		mutex_lock(&dev_info->mlock);
+		if (chan->address == AD7280A_ALL_CELLS)
+			ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
+		else
+			ret = ad7280_read_channel(st, chan->address >> 8,
+						  chan->address & 0xFF);
+		mutex_unlock(&dev_info->mlock);
+
+		if (ret < 0)
+			return ret;
+
+		*val = ret;
+
+		return IIO_VAL_INT;
+	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+		if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6)
+			scale_uv = (4000 * 1000) >> AD7280A_BITS;
+		else
+			scale_uv = (5000 * 1000) >> AD7280A_BITS;
+
+		*val =  scale_uv / 1000;
+		*val2 = (scale_uv % 1000) * 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+	return -EINVAL;
+}
+
+static const struct iio_info ad7280_info = {
+	.read_raw = &ad7280_read_raw,
+	.num_interrupt_lines = 1,
+	.event_attrs = &ad7280_event_attrs_group,
+	.attrs = &ad7280_attrs_group,
+	.driver_module = THIS_MODULE,
+};
+
+static const struct ad7280_platform_data ad7793_default_pdata = {
+	.acquisition_time = AD7280A_ACQ_TIME_400ns,
+	.conversion_averaging = AD7280A_CONV_AVG_DIS,
+	.thermistor_term_en = true,
+};
+
+static int __devinit ad7280_probe(struct spi_device *spi)
+{
+	const struct ad7280_platform_data *pdata = spi->dev.platform_data;
+	struct ad7280_state *st;
+	int ret, regdone = 0;
+	const unsigned short tACQ_ns[4] = {465, 1010, 1460, 1890};
+	const unsigned short nAVG[4] = {1, 2, 4, 8};
+	struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
+
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	spi_set_drvdata(spi, indio_dev);
+	st->spi = spi;
+
+	if (!pdata)
+		pdata = &ad7793_default_pdata;
+
+	ad7280_crc8_build_table(st->crc_tab);
+
+	st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_Hz;
+	st->spi->mode = SPI_MODE_1;
+	spi_setup(st->spi);
+
+	st->ctrl_lb = AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & 0x3);
+	st->ctrl_hb = AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averaging
+			& 0x3) | (pdata->thermistor_term_en ?
+			AD7280A_CTRL_LB_THERMISTOR_EN : 0);
+
+	ret = ad7280_chain_setup(st);
+	if (ret < 0)
+		goto error_free_device;
+
+	st->slave_num = ret;
+	st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
+	st->cell_threshhigh = 0xFF;
+	st->aux_threshhigh = 0xFF;
+
+	/*
+	 * Total Conversion Time = ((tACQ + tCONV) *
+	 *			   (Number of Conversions per Part)) −
+	 *			   tACQ + ((N - 1) * tDELAY)
+	 *
+	 * Readback Delay = Total Conversion Time + tWAIT
+	 */
+
+	st->readback_delay_us =
+		((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
+		(AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
+		- tACQ_ns[pdata->acquisition_time & 0x3] +
+		st->slave_num * 250;
+
+	/* Convert to usecs */
+	st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);
+	st->readback_delay_us += 5; /* Add tWAIT */
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = ad7280_channel_init(st);
+	if (ret < 0)
+		goto error_free_device;
+
+	indio_dev->num_channels = ret;
+	indio_dev->channels = st->channels;
+	indio_dev->info = &ad7280_info;
+
+	ret = ad7280_attr_init(st);
+	if (ret < 0)
+		goto error_free_channels;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_free_attr;
+	regdone = 1;
+
+	if (spi->irq > 0) {
+		ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
+				   AD7280A_ALERT, 1,
+				   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
+		if (ret)
+			goto error_free_attr;
+
+		ret = ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
+				   AD7280A_ALERT, 0,
+				   AD7280A_ALERT_GEN_STATIC_HIGH |
+				   (pdata->chain_last_alert_ignore & 0xF));
+		if (ret)
+			goto error_free_attr;
+
+		ret = request_threaded_irq(spi->irq,
+					   NULL,
+					   ad7280_event_handler,
+					   IRQF_TRIGGER_FALLING |
+					   IRQF_ONESHOT,
+					   indio_dev->name,
+					   indio_dev);
+		if (ret)
+			goto error_free_attr;
+	}
+
+	return 0;
+
+error_free_attr:
+	kfree(st->iio_attr);
+
+error_free_channels:
+	kfree(st->channels);
+
+error_free_device:
+	if (regdone)
+		iio_device_unregister(indio_dev);
+	else
+		iio_free_device(indio_dev);
+
+	return ret;
+}
+
+static int __devexit ad7280_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ad7280_state *st = iio_priv(indio_dev);
+
+	if (spi->irq > 0)
+		free_irq(spi->irq, indio_dev);
+
+	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
+			AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
+
+	kfree(st->channels);
+	kfree(st->iio_attr);
+	iio_device_unregister(indio_dev);
+
+	return 0;
+}
+
+static const struct spi_device_id ad7280_id[] = {
+	{"ad7280a", 0},
+	{}
+};
+
+static struct spi_driver ad7280_driver = {
+	.driver = {
+		.name	= "ad7280",
+		.bus	= &spi_bus_type,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ad7280_probe,
+	.remove		= __devexit_p(ad7280_remove),
+	.id_table	= ad7280_id,
+};
+
+static int __init ad7280_init(void)
+{
+	return spi_register_driver(&ad7280_driver);
+}
+module_init(ad7280_init);
+
+static void __exit ad7280_exit(void)
+{
+	spi_unregister_driver(&ad7280_driver);
+}
+module_exit(ad7280_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7280A");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/iio/adc/ad7280a.h b/drivers/staging/iio/adc/ad7280a.h
new file mode 100644
index 0000000..20400b0
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7280a.h
@@ -0,0 +1,38 @@
+/*
+ * AD7280A Lithium Ion Battery Monitoring System
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_ADC_AD7280_H_
+#define IIO_ADC_AD7280_H_
+
+/*
+ * TODO: struct ad7280_platform_data needs to go into include/linux/iio
+ */
+
+#define AD7280A_ACQ_TIME_400ns			0
+#define AD7280A_ACQ_TIME_800ns			1
+#define AD7280A_ACQ_TIME_1200ns			2
+#define AD7280A_ACQ_TIME_1600ns			3
+
+#define AD7280A_CONV_AVG_DIS			0
+#define AD7280A_CONV_AVG_2			1
+#define AD7280A_CONV_AVG_4			2
+#define AD7280A_CONV_AVG_8			3
+
+#define AD7280A_ALERT_REMOVE_VIN5		(1 << 2)
+#define AD7280A_ALERT_REMOVE_VIN4_VIN5		(2 << 2)
+#define AD7280A_ALERT_REMOVE_AUX5		(1 << 0)
+#define AD7280A_ALERT_REMOVE_AUX4_AUX5		(2 << 0)
+
+struct ad7280_platform_data {
+	unsigned acquisition_time;
+	unsigned conversion_averaging;
+	unsigned chain_last_alert_ignore;
+	bool thermistor_term_en;
+};
+
+#endif /* IIO_ADC_AD7280_H_ */
-- 
1.7.0.4

^ permalink raw reply related	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2011-07-20 13:03 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-07-15 12:59 [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec michael.hennerich
2011-07-15 12:59 ` [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System michael.hennerich
2011-07-18 11:43   ` Jonathan Cameron
2011-07-18 12:48     ` Michael Hennerich
2011-07-18 12:56       ` Jonathan Cameron
2011-07-18 13:36         ` Michael Hennerich
2011-07-18 13:41           ` Jonathan Cameron
2011-07-18 13:47             ` Michael Hennerich
2011-07-18 15:06           ` Michael Hennerich
2011-07-18 15:12             ` Jonathan Cameron
2011-07-15 13:19 ` [PATCH 1/2] iio: core: deconstify members of struct iio_chan_spec Jonathan Cameron
  -- strict thread matches above, loose matches on Subject: below --
2011-07-20 13:03 michael.hennerich
2011-07-20 13:03 ` [PATCH 2/2] iio: adc: New driver for AD7280A Lithium Ion Battery Monitoring System michael.hennerich
2011-07-20 13:03 ` michael.hennerich

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