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* [PATCH v3] IIO ADC support for AD7923
@ 2013-02-13  6:47 Christophe Leroy
  2013-02-13  9:19 ` Lars-Peter Clausen
  0 siblings, 1 reply; 4+ messages in thread
From: Christophe Leroy @ 2013-02-13  6:47 UTC (permalink / raw)
  To: Jonathan Cameron; +Cc: linux-kernel, linux-iio, patrick.vasseur

This patch adds support for Analog Devices AD7923 ADC in the IIO Subsystem.

Signed-off-by: Patrick Vasseur <patrick.vasseur@c-s.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

diff -urN linux-next-e347c98/drivers/iio/adc/Kconfig linux-next-e347c98.new/drivers/iio/adc/Kconfig
--- linux-next-e347c98/drivers/iio/adc/Kconfig	2013-02-08 05:22:35.000000000 +0100
+++ linux-next-e347c98.new/drivers/iio/adc/Kconfig	2013-02-12 13:02:52.000000000 +0100
@@ -30,6 +30,18 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad7298.
 
+config AD7923
+	tristate "Analog Devices AD7923 ADC driver"
+	depends on SPI
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes here to build support for Analog Devices AD7923
+	  4 Channel ADC with temperature sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad7923.
+
 config AD7791
 	tristate "Analog Devices AD7791 ADC driver"
 	depends on SPI
diff -urN linux-next-e347c98/drivers/iio/adc/Makefile linux-next-e347c98.new/drivers/iio/adc/Makefile
--- linux-next-e347c98/drivers/iio/adc/Makefile	2013-02-08 05:22:35.000000000 +0100
+++ linux-next-e347c98.new/drivers/iio/adc/Makefile	2013-02-12 13:03:02.000000000 +0100
@@ -5,6 +5,7 @@
 obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
 obj-$(CONFIG_AD7266) += ad7266.o
 obj-$(CONFIG_AD7298) += ad7298.o
+obj-$(CONFIG_AD7923) += ad7923.o
 obj-$(CONFIG_AD7476) += ad7476.o
 obj-$(CONFIG_AD7791) += ad7791.o
 obj-$(CONFIG_AD7793) += ad7793.o
diff -urN linux-next-e347c98/drivers/iio/adc/ad7923.c linux-next-e347c98.new/drivers/iio/adc/ad7923.c
--- linux-next-e347c98/drivers/iio/adc/ad7923.c	1970-01-01 01:00:00.000000000 +0100
+++ linux-next-e347c98.new/drivers/iio/adc/ad7923.c	2013-02-13 02:03:38.000000000 +0100
@@ -0,0 +1,298 @@
+/*
+ * AD7923 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc (from AD7923 Driver)
+ * Copyright 2012 CS Systemes d'Information
+ *
+ * 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/module.h>
+#include <linux/interrupt.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define AD7923_WRITE_CR		(1 << 11)	/* write control register */
+#define AD7923_RANGE		(1 << 1)	/* range to REFin */
+#define AD7923_CODING		(1 << 0)	/* coding is straight binary */
+#define AD7923_PM_MODE_AS	(1)		/* auto shutdown */
+#define AD7923_PM_MODE_FS	(2)		/* full shutdown */
+#define AD7923_PM_MODE_OPS	(3)		/* normal operation */
+#define AD7923_CHANNEL_0	(0)		/* analog input 0 */
+#define AD7923_CHANNEL_1	(1)		/* analog input 1 */
+#define AD7923_CHANNEL_2	(2)		/* analog input 2 */
+#define AD7923_CHANNEL_3	(3)		/* analog input 3 */
+#define AD7923_SEQUENCE_OFF	(0)		/* no sequence fonction */
+#define AD7923_SEQUENCE_PROTECT	(2)		/* no interrupt write cycle */
+#define AD7923_SEQUENCE_ON	(3)		/* continuous sequence */
+
+#define AD7923_MAX_CHAN		4
+
+#define AD7923_PM_MODE_WRITE(mode)	(mode << 4)	/* write mode */
+#define AD7923_CHANNEL_WRITE(channel)	(channel << 6)	/* write channel */
+#define AD7923_SEQUENCE_WRITE(sequence)	(((sequence & 1) << 3) \
+					+ ((sequence & 2) << 9))
+						/* write sequence fonction */
+/* left shift for CR : bit 11 transmit in first */
+#define AD7923_SHIFT_REGISTER	4
+
+/* val = value, dec = left shift, bits = number of bits of the mask */
+#define EXTRACT(val, dec, bits)		((val >> dec) & ((1 << bits) - 1))
+
+struct ad7923_state {
+	struct spi_device		*spi;
+	struct spi_transfer		ring_xfer[5];
+	struct spi_transfer		scan_single_xfer[2];
+	struct spi_message		ring_msg;
+	struct spi_message		scan_single_msg;
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+	__be16				rx_buf[4] ____cacheline_aligned;
+	__be16				tx_buf[4];
+};
+
+#define AD7923_V_CHAN(index)						\
+	{								\
+		.type = IIO_VOLTAGE,					\
+		.indexed = 1,						\
+		.channel = index,					\
+		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |		\
+		IIO_CHAN_INFO_SCALE_SHARED_BIT,				\
+		.address = index,					\
+		.scan_index = index,					\
+		.scan_type = {						\
+			.sign = 'u',					\
+			.realbits = 12,					\
+			.storagebits = 16,				\
+			.endianness = IIO_BE,				\
+		},							\
+	}
+
+static const struct iio_chan_spec ad7923_channels[] = {
+	AD7923_V_CHAN(0),
+	AD7923_V_CHAN(1),
+	AD7923_V_CHAN(2),
+	AD7923_V_CHAN(3),
+	IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+/**
+ * ad7923_update_scan_mode() setup the spi transfer buffer for the new scan mask
+ **/
+static int ad7923_update_scan_mode(struct iio_dev *indio_dev,
+	const unsigned long *active_scan_mask)
+{
+	struct ad7923_state *st = iio_priv(indio_dev);
+	int i, cmd, len;
+
+	len = 0;
+	for_each_set_bit(i, active_scan_mask, AD7923_MAX_CHAN) {
+		cmd = AD7923_WRITE_CR | AD7923_CODING | AD7923_RANGE |
+			AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
+			AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
+			AD7923_CHANNEL_WRITE(i);
+		cmd <<= AD7923_SHIFT_REGISTER;
+		st->tx_buf[len++] = cpu_to_be16(cmd);
+	}
+	/* build spi ring message */
+	st->ring_xfer[0].tx_buf = &st->tx_buf[0];
+	st->ring_xfer[0].len = len;
+	st->ring_xfer[0].cs_change = 1;
+
+	spi_message_init(&st->ring_msg);
+	spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
+
+	for (i = 0; i < len; i++) {
+		st->ring_xfer[i + 1].rx_buf = &st->rx_buf[i];
+		st->ring_xfer[i + 1].len = 2;
+		st->ring_xfer[i + 1].cs_change = 1;
+		spi_message_add_tail(&st->ring_xfer[i + 1], &st->ring_msg);
+	}
+	/* make sure last transfer cs_change is not set */
+	st->ring_xfer[i + 1].cs_change = 0;
+
+	return 0;
+}
+
+/**
+ * ad7923_trigger_handler() bh of trigger launched polling to ring buffer
+ *
+ * Currently there is no option in this driver to disable the saving of
+ * timestamps within the ring.
+ **/
+static irqreturn_t ad7923_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct ad7923_state *st = iio_priv(indio_dev);
+	s64 time_ns = 0;
+	int b_sent;
+
+	b_sent = spi_sync(st->spi, &st->ring_msg);
+	if (b_sent)
+		goto done;
+
+	if (indio_dev->scan_timestamp) {
+		time_ns = iio_get_time_ns();
+		memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
+			&time_ns, sizeof(time_ns));
+	}
+
+	iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
+
+done:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int ad7923_scan_direct(struct ad7923_state *st, unsigned ch)
+{
+	int ret, cmd;
+
+	cmd = AD7923_WRITE_CR | AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
+		AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) | AD7923_CODING |
+		AD7923_CHANNEL_WRITE(ch) | AD7923_RANGE;
+	cmd <<= AD7923_SHIFT_REGISTER;
+	st->tx_buf[0] = cpu_to_be16(cmd);
+
+	ret = spi_sync(st->spi, &st->scan_single_msg);
+	if (ret)
+		return ret;
+
+	return be16_to_cpu(st->rx_buf[0]);
+}
+
+static int ad7923_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	int ret;
+	struct ad7923_state *st = iio_priv(indio_dev);
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&indio_dev->mlock);
+		if (iio_buffer_enabled(indio_dev))
+			ret = -EBUSY;
+		else
+			ret = ad7923_scan_direct(st, chan->address);
+		mutex_unlock(&indio_dev->mlock);
+
+		if (ret < 0)
+			return ret;
+
+		if (chan->address == EXTRACT(ret, 12, 4))
+			*val = EXTRACT(ret, 0, 12);
+
+		return IIO_VAL_INT;
+	}
+	return -EINVAL;
+}
+
+static const struct iio_info ad7923_info = {
+	.read_raw = &ad7923_read_raw,
+	.update_scan_mode = ad7923_update_scan_mode,
+	.driver_module = THIS_MODULE,
+};
+
+static int ad7923_probe(struct spi_device *spi)
+{
+	struct ad7923_state *st;
+	struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
+	int ret;
+
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+
+	spi_set_drvdata(spi, indio_dev);
+
+	st->spi = spi;
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = ad7923_channels;
+	indio_dev->num_channels = ARRAY_SIZE(ad7923_channels);
+	indio_dev->info = &ad7923_info;
+
+	/* Setup default message */
+
+	st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
+	st->scan_single_xfer[0].len = 2;
+	st->scan_single_xfer[0].cs_change = 1;
+	st->scan_single_xfer[1].rx_buf = &st->rx_buf[0];
+	st->scan_single_xfer[1].len = 2;
+
+	spi_message_init(&st->scan_single_msg);
+	spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
+	spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
+
+	ret = iio_triggered_buffer_setup(indio_dev, NULL,
+			&ad7923_trigger_handler, NULL);
+	if (ret)
+		goto error_free;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_cleanup_ring;
+
+	return 0;
+
+error_cleanup_ring:
+	iio_triggered_buffer_cleanup(indio_dev);
+error_free:
+	iio_device_free(indio_dev);
+
+	return ret;
+}
+
+static int ad7923_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+	iio_device_free(indio_dev);
+
+	return 0;
+}
+
+static const struct spi_device_id ad7923_id[] = {
+	{"ad7923", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, ad7923_id);
+
+static struct spi_driver ad7923_driver = {
+	.driver = {
+		.name	= "ad7923",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ad7923_probe,
+	.remove		= ad7923_remove,
+	.id_table	= ad7923_id,
+};
+module_spi_driver(ad7923_driver);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_AUTHOR("Patrick Vasseur <patrick.vasseur@c-s.fr>");
+MODULE_DESCRIPTION("Analog Devices AD7923 ADC");
+MODULE_LICENSE("GPL v2");

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v3] IIO ADC support for AD7923
  2013-02-13  6:47 [PATCH v3] IIO ADC support for AD7923 Christophe Leroy
@ 2013-02-13  9:19 ` Lars-Peter Clausen
  2013-02-13  9:20   ` Jonathan Cameron
  0 siblings, 1 reply; 4+ messages in thread
From: Lars-Peter Clausen @ 2013-02-13  9:19 UTC (permalink / raw)
  To: Christophe Leroy
  Cc: Jonathan Cameron, linux-kernel, linux-iio, patrick.vasseur

On 02/13/2013 07:47 AM, Christophe Leroy wrote:
> This patch adds support for Analog Devices AD7923 ADC in the IIO Subsystem.
> 
> Signed-off-by: Patrick Vasseur <patrick.vasseur@c-s.fr>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Looks good, thanks.

Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

> 
> diff -urN linux-next-e347c98/drivers/iio/adc/Kconfig linux-next-e347c98.new/drivers/iio/adc/Kconfig
> --- linux-next-e347c98/drivers/iio/adc/Kconfig	2013-02-08 05:22:35.000000000 +0100
> +++ linux-next-e347c98.new/drivers/iio/adc/Kconfig	2013-02-12 13:02:52.000000000 +0100
> @@ -30,6 +30,18 @@
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called ad7298.
>  
> +config AD7923
> +	tristate "Analog Devices AD7923 ADC driver"
> +	depends on SPI
> +	select IIO_BUFFER
> +	select IIO_TRIGGERED_BUFFER
> +	help
> +	  Say yes here to build support for Analog Devices AD7923
> +	  4 Channel ADC with temperature sensor.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called ad7923.
> +
>  config AD7791
>  	tristate "Analog Devices AD7791 ADC driver"
>  	depends on SPI
> diff -urN linux-next-e347c98/drivers/iio/adc/Makefile linux-next-e347c98.new/drivers/iio/adc/Makefile
> --- linux-next-e347c98/drivers/iio/adc/Makefile	2013-02-08 05:22:35.000000000 +0100
> +++ linux-next-e347c98.new/drivers/iio/adc/Makefile	2013-02-12 13:03:02.000000000 +0100
> @@ -5,6 +5,7 @@
>  obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
>  obj-$(CONFIG_AD7266) += ad7266.o
>  obj-$(CONFIG_AD7298) += ad7298.o
> +obj-$(CONFIG_AD7923) += ad7923.o
>  obj-$(CONFIG_AD7476) += ad7476.o
>  obj-$(CONFIG_AD7791) += ad7791.o
>  obj-$(CONFIG_AD7793) += ad7793.o
> diff -urN linux-next-e347c98/drivers/iio/adc/ad7923.c linux-next-e347c98.new/drivers/iio/adc/ad7923.c
> --- linux-next-e347c98/drivers/iio/adc/ad7923.c	1970-01-01 01:00:00.000000000 +0100
> +++ linux-next-e347c98.new/drivers/iio/adc/ad7923.c	2013-02-13 02:03:38.000000000 +0100
> @@ -0,0 +1,298 @@
> +/*
> + * AD7923 SPI ADC driver
> + *
> + * Copyright 2011 Analog Devices Inc (from AD7923 Driver)
> + * Copyright 2012 CS Systemes d'Information
> + *
> + * 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/module.h>
> +#include <linux/interrupt.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> +#define AD7923_WRITE_CR		(1 << 11)	/* write control register */
> +#define AD7923_RANGE		(1 << 1)	/* range to REFin */
> +#define AD7923_CODING		(1 << 0)	/* coding is straight binary */
> +#define AD7923_PM_MODE_AS	(1)		/* auto shutdown */
> +#define AD7923_PM_MODE_FS	(2)		/* full shutdown */
> +#define AD7923_PM_MODE_OPS	(3)		/* normal operation */
> +#define AD7923_CHANNEL_0	(0)		/* analog input 0 */
> +#define AD7923_CHANNEL_1	(1)		/* analog input 1 */
> +#define AD7923_CHANNEL_2	(2)		/* analog input 2 */
> +#define AD7923_CHANNEL_3	(3)		/* analog input 3 */
> +#define AD7923_SEQUENCE_OFF	(0)		/* no sequence fonction */
> +#define AD7923_SEQUENCE_PROTECT	(2)		/* no interrupt write cycle */
> +#define AD7923_SEQUENCE_ON	(3)		/* continuous sequence */
> +
> +#define AD7923_MAX_CHAN		4
> +
> +#define AD7923_PM_MODE_WRITE(mode)	(mode << 4)	/* write mode */
> +#define AD7923_CHANNEL_WRITE(channel)	(channel << 6)	/* write channel */
> +#define AD7923_SEQUENCE_WRITE(sequence)	(((sequence & 1) << 3) \
> +					+ ((sequence & 2) << 9))
> +						/* write sequence fonction */
> +/* left shift for CR : bit 11 transmit in first */
> +#define AD7923_SHIFT_REGISTER	4
> +
> +/* val = value, dec = left shift, bits = number of bits of the mask */
> +#define EXTRACT(val, dec, bits)		((val >> dec) & ((1 << bits) - 1))
> +
> +struct ad7923_state {
> +	struct spi_device		*spi;
> +	struct spi_transfer		ring_xfer[5];
> +	struct spi_transfer		scan_single_xfer[2];
> +	struct spi_message		ring_msg;
> +	struct spi_message		scan_single_msg;
> +	/*
> +	 * DMA (thus cache coherency maintenance) requires the
> +	 * transfer buffers to live in their own cache lines.
> +	 */
> +	__be16				rx_buf[4] ____cacheline_aligned;
> +	__be16				tx_buf[4];
> +};
> +
> +#define AD7923_V_CHAN(index)						\
> +	{								\
> +		.type = IIO_VOLTAGE,					\
> +		.indexed = 1,						\
> +		.channel = index,					\
> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |		\
> +		IIO_CHAN_INFO_SCALE_SHARED_BIT,				\
> +		.address = index,					\
> +		.scan_index = index,					\
> +		.scan_type = {						\
> +			.sign = 'u',					\
> +			.realbits = 12,					\
> +			.storagebits = 16,				\
> +			.endianness = IIO_BE,				\
> +		},							\
> +	}
> +
> +static const struct iio_chan_spec ad7923_channels[] = {
> +	AD7923_V_CHAN(0),
> +	AD7923_V_CHAN(1),
> +	AD7923_V_CHAN(2),
> +	AD7923_V_CHAN(3),
> +	IIO_CHAN_SOFT_TIMESTAMP(4),
> +};
> +
> +/**
> + * ad7923_update_scan_mode() setup the spi transfer buffer for the new scan mask
> + **/
> +static int ad7923_update_scan_mode(struct iio_dev *indio_dev,
> +	const unsigned long *active_scan_mask)
> +{
> +	struct ad7923_state *st = iio_priv(indio_dev);
> +	int i, cmd, len;
> +
> +	len = 0;
> +	for_each_set_bit(i, active_scan_mask, AD7923_MAX_CHAN) {
> +		cmd = AD7923_WRITE_CR | AD7923_CODING | AD7923_RANGE |
> +			AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
> +			AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
> +			AD7923_CHANNEL_WRITE(i);
> +		cmd <<= AD7923_SHIFT_REGISTER;
> +		st->tx_buf[len++] = cpu_to_be16(cmd);
> +	}
> +	/* build spi ring message */
> +	st->ring_xfer[0].tx_buf = &st->tx_buf[0];
> +	st->ring_xfer[0].len = len;
> +	st->ring_xfer[0].cs_change = 1;
> +
> +	spi_message_init(&st->ring_msg);
> +	spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
> +
> +	for (i = 0; i < len; i++) {
> +		st->ring_xfer[i + 1].rx_buf = &st->rx_buf[i];
> +		st->ring_xfer[i + 1].len = 2;
> +		st->ring_xfer[i + 1].cs_change = 1;
> +		spi_message_add_tail(&st->ring_xfer[i + 1], &st->ring_msg);
> +	}
> +	/* make sure last transfer cs_change is not set */
> +	st->ring_xfer[i + 1].cs_change = 0;
> +
> +	return 0;
> +}
> +
> +/**
> + * ad7923_trigger_handler() bh of trigger launched polling to ring buffer
> + *
> + * Currently there is no option in this driver to disable the saving of
> + * timestamps within the ring.
> + **/
> +static irqreturn_t ad7923_trigger_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *indio_dev = pf->indio_dev;
> +	struct ad7923_state *st = iio_priv(indio_dev);
> +	s64 time_ns = 0;
> +	int b_sent;
> +
> +	b_sent = spi_sync(st->spi, &st->ring_msg);
> +	if (b_sent)
> +		goto done;
> +
> +	if (indio_dev->scan_timestamp) {
> +		time_ns = iio_get_time_ns();
> +		memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
> +			&time_ns, sizeof(time_ns));
> +	}
> +
> +	iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
> +
> +done:
> +	iio_trigger_notify_done(indio_dev->trig);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int ad7923_scan_direct(struct ad7923_state *st, unsigned ch)
> +{
> +	int ret, cmd;
> +
> +	cmd = AD7923_WRITE_CR | AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
> +		AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) | AD7923_CODING |
> +		AD7923_CHANNEL_WRITE(ch) | AD7923_RANGE;
> +	cmd <<= AD7923_SHIFT_REGISTER;
> +	st->tx_buf[0] = cpu_to_be16(cmd);
> +
> +	ret = spi_sync(st->spi, &st->scan_single_msg);
> +	if (ret)
> +		return ret;
> +
> +	return be16_to_cpu(st->rx_buf[0]);
> +}
> +
> +static int ad7923_read_raw(struct iio_dev *indio_dev,
> +			   struct iio_chan_spec const *chan,
> +			   int *val,
> +			   int *val2,
> +			   long m)
> +{
> +	int ret;
> +	struct ad7923_state *st = iio_priv(indio_dev);
> +
> +	switch (m) {
> +	case IIO_CHAN_INFO_RAW:
> +		mutex_lock(&indio_dev->mlock);
> +		if (iio_buffer_enabled(indio_dev))
> +			ret = -EBUSY;
> +		else
> +			ret = ad7923_scan_direct(st, chan->address);
> +		mutex_unlock(&indio_dev->mlock);
> +
> +		if (ret < 0)
> +			return ret;
> +
> +		if (chan->address == EXTRACT(ret, 12, 4))
> +			*val = EXTRACT(ret, 0, 12);
> +
> +		return IIO_VAL_INT;
> +	}
> +	return -EINVAL;
> +}
> +
> +static const struct iio_info ad7923_info = {
> +	.read_raw = &ad7923_read_raw,
> +	.update_scan_mode = ad7923_update_scan_mode,
> +	.driver_module = THIS_MODULE,
> +};
> +
> +static int ad7923_probe(struct spi_device *spi)
> +{
> +	struct ad7923_state *st;
> +	struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
> +	int ret;
> +
> +	if (indio_dev == NULL)
> +		return -ENOMEM;
> +
> +	st = iio_priv(indio_dev);
> +
> +	spi_set_drvdata(spi, indio_dev);
> +
> +	st->spi = spi;
> +
> +	indio_dev->name = spi_get_device_id(spi)->name;
> +	indio_dev->dev.parent = &spi->dev;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels = ad7923_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(ad7923_channels);
> +	indio_dev->info = &ad7923_info;
> +
> +	/* Setup default message */
> +
> +	st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
> +	st->scan_single_xfer[0].len = 2;
> +	st->scan_single_xfer[0].cs_change = 1;
> +	st->scan_single_xfer[1].rx_buf = &st->rx_buf[0];
> +	st->scan_single_xfer[1].len = 2;
> +
> +	spi_message_init(&st->scan_single_msg);
> +	spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
> +	spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
> +
> +	ret = iio_triggered_buffer_setup(indio_dev, NULL,
> +			&ad7923_trigger_handler, NULL);
> +	if (ret)
> +		goto error_free;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret)
> +		goto error_cleanup_ring;
> +
> +	return 0;
> +
> +error_cleanup_ring:
> +	iio_triggered_buffer_cleanup(indio_dev);
> +error_free:
> +	iio_device_free(indio_dev);
> +
> +	return ret;
> +}
> +
> +static int ad7923_remove(struct spi_device *spi)
> +{
> +	struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +
> +	iio_device_unregister(indio_dev);
> +	iio_triggered_buffer_cleanup(indio_dev);
> +	iio_device_free(indio_dev);
> +
> +	return 0;
> +}
> +
> +static const struct spi_device_id ad7923_id[] = {
> +	{"ad7923", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(spi, ad7923_id);
> +
> +static struct spi_driver ad7923_driver = {
> +	.driver = {
> +		.name	= "ad7923",
> +		.owner	= THIS_MODULE,
> +	},
> +	.probe		= ad7923_probe,
> +	.remove		= ad7923_remove,
> +	.id_table	= ad7923_id,
> +};
> +module_spi_driver(ad7923_driver);
> +
> +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
> +MODULE_AUTHOR("Patrick Vasseur <patrick.vasseur@c-s.fr>");
> +MODULE_DESCRIPTION("Analog Devices AD7923 ADC");
> +MODULE_LICENSE("GPL v2");
> --
> 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


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v3] IIO ADC support for AD7923
  2013-02-13  9:19 ` Lars-Peter Clausen
@ 2013-02-13  9:20   ` Jonathan Cameron
  2013-03-03 12:11     ` Jonathan Cameron
  0 siblings, 1 reply; 4+ messages in thread
From: Jonathan Cameron @ 2013-02-13  9:20 UTC (permalink / raw)
  To: Lars-Peter Clausen
  Cc: Christophe Leroy, Jonathan Cameron, linux-kernel, linux-iio,
	patrick.vasseur

On 13/02/13 09:19, Lars-Peter Clausen wrote:
> On 02/13/2013 07:47 AM, Christophe Leroy wrote:
>> This patch adds support for Analog Devices AD7923 ADC in the IIO Subsystem.
>>
>> Signed-off-by: Patrick Vasseur <patrick.vasseur@c-s.fr>
>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>
> Looks good, thanks.
>
> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Just missed the merge window I'm afraid. I'll queue this up for
going into staging-next after Linus closes the main merge window.
>
>>
>> diff -urN linux-next-e347c98/drivers/iio/adc/Kconfig linux-next-e347c98.new/drivers/iio/adc/Kconfig
>> --- linux-next-e347c98/drivers/iio/adc/Kconfig	2013-02-08 05:22:35.000000000 +0100
>> +++ linux-next-e347c98.new/drivers/iio/adc/Kconfig	2013-02-12 13:02:52.000000000 +0100
>> @@ -30,6 +30,18 @@
>>   	  To compile this driver as a module, choose M here: the
>>   	  module will be called ad7298.
>>
>> +config AD7923
>> +	tristate "Analog Devices AD7923 ADC driver"
>> +	depends on SPI
>> +	select IIO_BUFFER
>> +	select IIO_TRIGGERED_BUFFER
>> +	help
>> +	  Say yes here to build support for Analog Devices AD7923
>> +	  4 Channel ADC with temperature sensor.
>> +
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called ad7923.
>> +
>>   config AD7791
>>   	tristate "Analog Devices AD7791 ADC driver"
>>   	depends on SPI
>> diff -urN linux-next-e347c98/drivers/iio/adc/Makefile linux-next-e347c98.new/drivers/iio/adc/Makefile
>> --- linux-next-e347c98/drivers/iio/adc/Makefile	2013-02-08 05:22:35.000000000 +0100
>> +++ linux-next-e347c98.new/drivers/iio/adc/Makefile	2013-02-12 13:03:02.000000000 +0100
>> @@ -5,6 +5,7 @@
>>   obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
>>   obj-$(CONFIG_AD7266) += ad7266.o
>>   obj-$(CONFIG_AD7298) += ad7298.o
>> +obj-$(CONFIG_AD7923) += ad7923.o
>>   obj-$(CONFIG_AD7476) += ad7476.o
>>   obj-$(CONFIG_AD7791) += ad7791.o
>>   obj-$(CONFIG_AD7793) += ad7793.o
>> diff -urN linux-next-e347c98/drivers/iio/adc/ad7923.c linux-next-e347c98.new/drivers/iio/adc/ad7923.c
>> --- linux-next-e347c98/drivers/iio/adc/ad7923.c	1970-01-01 01:00:00.000000000 +0100
>> +++ linux-next-e347c98.new/drivers/iio/adc/ad7923.c	2013-02-13 02:03:38.000000000 +0100
>> @@ -0,0 +1,298 @@
>> +/*
>> + * AD7923 SPI ADC driver
>> + *
>> + * Copyright 2011 Analog Devices Inc (from AD7923 Driver)
>> + * Copyright 2012 CS Systemes d'Information
>> + *
>> + * 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/module.h>
>> +#include <linux/interrupt.h>
>> +
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +#include <linux/iio/buffer.h>
>> +#include <linux/iio/trigger_consumer.h>
>> +#include <linux/iio/triggered_buffer.h>
>> +
>> +#define AD7923_WRITE_CR		(1 << 11)	/* write control register */
>> +#define AD7923_RANGE		(1 << 1)	/* range to REFin */
>> +#define AD7923_CODING		(1 << 0)	/* coding is straight binary */
>> +#define AD7923_PM_MODE_AS	(1)		/* auto shutdown */
>> +#define AD7923_PM_MODE_FS	(2)		/* full shutdown */
>> +#define AD7923_PM_MODE_OPS	(3)		/* normal operation */
>> +#define AD7923_CHANNEL_0	(0)		/* analog input 0 */
>> +#define AD7923_CHANNEL_1	(1)		/* analog input 1 */
>> +#define AD7923_CHANNEL_2	(2)		/* analog input 2 */
>> +#define AD7923_CHANNEL_3	(3)		/* analog input 3 */
>> +#define AD7923_SEQUENCE_OFF	(0)		/* no sequence fonction */
>> +#define AD7923_SEQUENCE_PROTECT	(2)		/* no interrupt write cycle */
>> +#define AD7923_SEQUENCE_ON	(3)		/* continuous sequence */
>> +
>> +#define AD7923_MAX_CHAN		4
>> +
>> +#define AD7923_PM_MODE_WRITE(mode)	(mode << 4)	/* write mode */
>> +#define AD7923_CHANNEL_WRITE(channel)	(channel << 6)	/* write channel */
>> +#define AD7923_SEQUENCE_WRITE(sequence)	(((sequence & 1) << 3) \
>> +					+ ((sequence & 2) << 9))
>> +						/* write sequence fonction */
>> +/* left shift for CR : bit 11 transmit in first */
>> +#define AD7923_SHIFT_REGISTER	4
>> +
>> +/* val = value, dec = left shift, bits = number of bits of the mask */
>> +#define EXTRACT(val, dec, bits)		((val >> dec) & ((1 << bits) - 1))
>> +
>> +struct ad7923_state {
>> +	struct spi_device		*spi;
>> +	struct spi_transfer		ring_xfer[5];
>> +	struct spi_transfer		scan_single_xfer[2];
>> +	struct spi_message		ring_msg;
>> +	struct spi_message		scan_single_msg;
>> +	/*
>> +	 * DMA (thus cache coherency maintenance) requires the
>> +	 * transfer buffers to live in their own cache lines.
>> +	 */
>> +	__be16				rx_buf[4] ____cacheline_aligned;
>> +	__be16				tx_buf[4];
>> +};
>> +
>> +#define AD7923_V_CHAN(index)						\
>> +	{								\
>> +		.type = IIO_VOLTAGE,					\
>> +		.indexed = 1,						\
>> +		.channel = index,					\
>> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |		\
>> +		IIO_CHAN_INFO_SCALE_SHARED_BIT,				\
>> +		.address = index,					\
>> +		.scan_index = index,					\
>> +		.scan_type = {						\
>> +			.sign = 'u',					\
>> +			.realbits = 12,					\
>> +			.storagebits = 16,				\
>> +			.endianness = IIO_BE,				\
>> +		},							\
>> +	}
>> +
>> +static const struct iio_chan_spec ad7923_channels[] = {
>> +	AD7923_V_CHAN(0),
>> +	AD7923_V_CHAN(1),
>> +	AD7923_V_CHAN(2),
>> +	AD7923_V_CHAN(3),
>> +	IIO_CHAN_SOFT_TIMESTAMP(4),
>> +};
>> +
>> +/**
>> + * ad7923_update_scan_mode() setup the spi transfer buffer for the new scan mask
>> + **/
>> +static int ad7923_update_scan_mode(struct iio_dev *indio_dev,
>> +	const unsigned long *active_scan_mask)
>> +{
>> +	struct ad7923_state *st = iio_priv(indio_dev);
>> +	int i, cmd, len;
>> +
>> +	len = 0;
>> +	for_each_set_bit(i, active_scan_mask, AD7923_MAX_CHAN) {
>> +		cmd = AD7923_WRITE_CR | AD7923_CODING | AD7923_RANGE |
>> +			AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
>> +			AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
>> +			AD7923_CHANNEL_WRITE(i);
>> +		cmd <<= AD7923_SHIFT_REGISTER;
>> +		st->tx_buf[len++] = cpu_to_be16(cmd);
>> +	}
>> +	/* build spi ring message */
>> +	st->ring_xfer[0].tx_buf = &st->tx_buf[0];
>> +	st->ring_xfer[0].len = len;
>> +	st->ring_xfer[0].cs_change = 1;
>> +
>> +	spi_message_init(&st->ring_msg);
>> +	spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
>> +
>> +	for (i = 0; i < len; i++) {
>> +		st->ring_xfer[i + 1].rx_buf = &st->rx_buf[i];
>> +		st->ring_xfer[i + 1].len = 2;
>> +		st->ring_xfer[i + 1].cs_change = 1;
>> +		spi_message_add_tail(&st->ring_xfer[i + 1], &st->ring_msg);
>> +	}
>> +	/* make sure last transfer cs_change is not set */
>> +	st->ring_xfer[i + 1].cs_change = 0;
>> +
>> +	return 0;
>> +}
>> +
>> +/**
>> + * ad7923_trigger_handler() bh of trigger launched polling to ring buffer
>> + *
>> + * Currently there is no option in this driver to disable the saving of
>> + * timestamps within the ring.
>> + **/
>> +static irqreturn_t ad7923_trigger_handler(int irq, void *p)
>> +{
>> +	struct iio_poll_func *pf = p;
>> +	struct iio_dev *indio_dev = pf->indio_dev;
>> +	struct ad7923_state *st = iio_priv(indio_dev);
>> +	s64 time_ns = 0;
>> +	int b_sent;
>> +
>> +	b_sent = spi_sync(st->spi, &st->ring_msg);
>> +	if (b_sent)
>> +		goto done;
>> +
>> +	if (indio_dev->scan_timestamp) {
>> +		time_ns = iio_get_time_ns();
>> +		memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
>> +			&time_ns, sizeof(time_ns));
>> +	}
>> +
>> +	iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
>> +
>> +done:
>> +	iio_trigger_notify_done(indio_dev->trig);
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int ad7923_scan_direct(struct ad7923_state *st, unsigned ch)
>> +{
>> +	int ret, cmd;
>> +
>> +	cmd = AD7923_WRITE_CR | AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
>> +		AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) | AD7923_CODING |
>> +		AD7923_CHANNEL_WRITE(ch) | AD7923_RANGE;
>> +	cmd <<= AD7923_SHIFT_REGISTER;
>> +	st->tx_buf[0] = cpu_to_be16(cmd);
>> +
>> +	ret = spi_sync(st->spi, &st->scan_single_msg);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return be16_to_cpu(st->rx_buf[0]);
>> +}
>> +
>> +static int ad7923_read_raw(struct iio_dev *indio_dev,
>> +			   struct iio_chan_spec const *chan,
>> +			   int *val,
>> +			   int *val2,
>> +			   long m)
>> +{
>> +	int ret;
>> +	struct ad7923_state *st = iio_priv(indio_dev);
>> +
>> +	switch (m) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		mutex_lock(&indio_dev->mlock);
>> +		if (iio_buffer_enabled(indio_dev))
>> +			ret = -EBUSY;
>> +		else
>> +			ret = ad7923_scan_direct(st, chan->address);
>> +		mutex_unlock(&indio_dev->mlock);
>> +
>> +		if (ret < 0)
>> +			return ret;
>> +
>> +		if (chan->address == EXTRACT(ret, 12, 4))
>> +			*val = EXTRACT(ret, 0, 12);
>> +
>> +		return IIO_VAL_INT;
>> +	}
>> +	return -EINVAL;
>> +}
>> +
>> +static const struct iio_info ad7923_info = {
>> +	.read_raw = &ad7923_read_raw,
>> +	.update_scan_mode = ad7923_update_scan_mode,
>> +	.driver_module = THIS_MODULE,
>> +};
>> +
>> +static int ad7923_probe(struct spi_device *spi)
>> +{
>> +	struct ad7923_state *st;
>> +	struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
>> +	int ret;
>> +
>> +	if (indio_dev == NULL)
>> +		return -ENOMEM;
>> +
>> +	st = iio_priv(indio_dev);
>> +
>> +	spi_set_drvdata(spi, indio_dev);
>> +
>> +	st->spi = spi;
>> +
>> +	indio_dev->name = spi_get_device_id(spi)->name;
>> +	indio_dev->dev.parent = &spi->dev;
>> +	indio_dev->modes = INDIO_DIRECT_MODE;
>> +	indio_dev->channels = ad7923_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(ad7923_channels);
>> +	indio_dev->info = &ad7923_info;
>> +
>> +	/* Setup default message */
>> +
>> +	st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
>> +	st->scan_single_xfer[0].len = 2;
>> +	st->scan_single_xfer[0].cs_change = 1;
>> +	st->scan_single_xfer[1].rx_buf = &st->rx_buf[0];
>> +	st->scan_single_xfer[1].len = 2;
>> +
>> +	spi_message_init(&st->scan_single_msg);
>> +	spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
>> +	spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
>> +
>> +	ret = iio_triggered_buffer_setup(indio_dev, NULL,
>> +			&ad7923_trigger_handler, NULL);
>> +	if (ret)
>> +		goto error_free;
>> +
>> +	ret = iio_device_register(indio_dev);
>> +	if (ret)
>> +		goto error_cleanup_ring;
>> +
>> +	return 0;
>> +
>> +error_cleanup_ring:
>> +	iio_triggered_buffer_cleanup(indio_dev);
>> +error_free:
>> +	iio_device_free(indio_dev);
>> +
>> +	return ret;
>> +}
>> +
>> +static int ad7923_remove(struct spi_device *spi)
>> +{
>> +	struct iio_dev *indio_dev = spi_get_drvdata(spi);
>> +
>> +	iio_device_unregister(indio_dev);
>> +	iio_triggered_buffer_cleanup(indio_dev);
>> +	iio_device_free(indio_dev);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct spi_device_id ad7923_id[] = {
>> +	{"ad7923", 0},
>> +	{}
>> +};
>> +MODULE_DEVICE_TABLE(spi, ad7923_id);
>> +
>> +static struct spi_driver ad7923_driver = {
>> +	.driver = {
>> +		.name	= "ad7923",
>> +		.owner	= THIS_MODULE,
>> +	},
>> +	.probe		= ad7923_probe,
>> +	.remove		= ad7923_remove,
>> +	.id_table	= ad7923_id,
>> +};
>> +module_spi_driver(ad7923_driver);
>> +
>> +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
>> +MODULE_AUTHOR("Patrick Vasseur <patrick.vasseur@c-s.fr>");
>> +MODULE_DESCRIPTION("Analog Devices AD7923 ADC");
>> +MODULE_LICENSE("GPL v2");
>> --
>> 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
>
> --
> 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
>


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v3] IIO ADC support for AD7923
  2013-02-13  9:20   ` Jonathan Cameron
@ 2013-03-03 12:11     ` Jonathan Cameron
  0 siblings, 0 replies; 4+ messages in thread
From: Jonathan Cameron @ 2013-03-03 12:11 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: Lars-Peter Clausen, Christophe Leroy, linux-kernel, linux-iio,
	patrick.vasseur

On 02/13/2013 09:20 AM, Jonathan Cameron wrote:
> On 13/02/13 09:19, Lars-Peter Clausen wrote:
>> On 02/13/2013 07:47 AM, Christophe Leroy wrote:
>>> This patch adds support for Analog Devices AD7923 ADC in the IIO Subsystem.
>>>
>>> Signed-off-by: Patrick Vasseur <patrick.vasseur@c-s.fr>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>
>> Looks good, thanks.
>>
>> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
> Just missed the merge window I'm afraid. I'll queue this up for
> going into staging-next after Linus closes the main merge window.

Applied to the togreg branch of iio.git
>>
>>>
>>> diff -urN linux-next-e347c98/drivers/iio/adc/Kconfig linux-next-e347c98.new/drivers/iio/adc/Kconfig
>>> --- linux-next-e347c98/drivers/iio/adc/Kconfig    2013-02-08 05:22:35.000000000 +0100
>>> +++ linux-next-e347c98.new/drivers/iio/adc/Kconfig    2013-02-12 13:02:52.000000000 +0100
>>> @@ -30,6 +30,18 @@
>>>         To compile this driver as a module, choose M here: the
>>>         module will be called ad7298.
>>>
>>> +config AD7923
>>> +    tristate "Analog Devices AD7923 ADC driver"
>>> +    depends on SPI
>>> +    select IIO_BUFFER
>>> +    select IIO_TRIGGERED_BUFFER
>>> +    help
>>> +      Say yes here to build support for Analog Devices AD7923
>>> +      4 Channel ADC with temperature sensor.
>>> +
>>> +      To compile this driver as a module, choose M here: the
>>> +      module will be called ad7923.
>>> +
>>>   config AD7791
>>>       tristate "Analog Devices AD7791 ADC driver"
>>>       depends on SPI
>>> diff -urN linux-next-e347c98/drivers/iio/adc/Makefile linux-next-e347c98.new/drivers/iio/adc/Makefile
>>> --- linux-next-e347c98/drivers/iio/adc/Makefile    2013-02-08 05:22:35.000000000 +0100
>>> +++ linux-next-e347c98.new/drivers/iio/adc/Makefile    2013-02-12 13:03:02.000000000 +0100
>>> @@ -5,6 +5,7 @@
>>>   obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
>>>   obj-$(CONFIG_AD7266) += ad7266.o
>>>   obj-$(CONFIG_AD7298) += ad7298.o
>>> +obj-$(CONFIG_AD7923) += ad7923.o
>>>   obj-$(CONFIG_AD7476) += ad7476.o
>>>   obj-$(CONFIG_AD7791) += ad7791.o
>>>   obj-$(CONFIG_AD7793) += ad7793.o
>>> diff -urN linux-next-e347c98/drivers/iio/adc/ad7923.c linux-next-e347c98.new/drivers/iio/adc/ad7923.c
>>> --- linux-next-e347c98/drivers/iio/adc/ad7923.c    1970-01-01 01:00:00.000000000 +0100
>>> +++ linux-next-e347c98.new/drivers/iio/adc/ad7923.c    2013-02-13 02:03:38.000000000 +0100
>>> @@ -0,0 +1,298 @@
>>> +/*
>>> + * AD7923 SPI ADC driver
>>> + *
>>> + * Copyright 2011 Analog Devices Inc (from AD7923 Driver)
>>> + * Copyright 2012 CS Systemes d'Information
>>> + *
>>> + * 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/module.h>
>>> +#include <linux/interrupt.h>
>>> +
>>> +#include <linux/iio/iio.h>
>>> +#include <linux/iio/sysfs.h>
>>> +#include <linux/iio/buffer.h>
>>> +#include <linux/iio/trigger_consumer.h>
>>> +#include <linux/iio/triggered_buffer.h>
>>> +
>>> +#define AD7923_WRITE_CR        (1 << 11)    /* write control register */
>>> +#define AD7923_RANGE        (1 << 1)    /* range to REFin */
>>> +#define AD7923_CODING        (1 << 0)    /* coding is straight binary */
>>> +#define AD7923_PM_MODE_AS    (1)        /* auto shutdown */
>>> +#define AD7923_PM_MODE_FS    (2)        /* full shutdown */
>>> +#define AD7923_PM_MODE_OPS    (3)        /* normal operation */
>>> +#define AD7923_CHANNEL_0    (0)        /* analog input 0 */
>>> +#define AD7923_CHANNEL_1    (1)        /* analog input 1 */
>>> +#define AD7923_CHANNEL_2    (2)        /* analog input 2 */
>>> +#define AD7923_CHANNEL_3    (3)        /* analog input 3 */
>>> +#define AD7923_SEQUENCE_OFF    (0)        /* no sequence fonction */
>>> +#define AD7923_SEQUENCE_PROTECT    (2)        /* no interrupt write cycle */
>>> +#define AD7923_SEQUENCE_ON    (3)        /* continuous sequence */
>>> +
>>> +#define AD7923_MAX_CHAN        4
>>> +
>>> +#define AD7923_PM_MODE_WRITE(mode)    (mode << 4)    /* write mode */
>>> +#define AD7923_CHANNEL_WRITE(channel)    (channel << 6)    /* write channel */
>>> +#define AD7923_SEQUENCE_WRITE(sequence)    (((sequence & 1) << 3) \
>>> +                    + ((sequence & 2) << 9))
>>> +                        /* write sequence fonction */
>>> +/* left shift for CR : bit 11 transmit in first */
>>> +#define AD7923_SHIFT_REGISTER    4
>>> +
>>> +/* val = value, dec = left shift, bits = number of bits of the mask */
>>> +#define EXTRACT(val, dec, bits)        ((val >> dec) & ((1 << bits) - 1))
>>> +
>>> +struct ad7923_state {
>>> +    struct spi_device        *spi;
>>> +    struct spi_transfer        ring_xfer[5];
>>> +    struct spi_transfer        scan_single_xfer[2];
>>> +    struct spi_message        ring_msg;
>>> +    struct spi_message        scan_single_msg;
>>> +    /*
>>> +     * DMA (thus cache coherency maintenance) requires the
>>> +     * transfer buffers to live in their own cache lines.
>>> +     */
>>> +    __be16                rx_buf[4] ____cacheline_aligned;
>>> +    __be16                tx_buf[4];
>>> +};
>>> +
>>> +#define AD7923_V_CHAN(index)                        \
>>> +    {                                \
>>> +        .type = IIO_VOLTAGE,                    \
>>> +        .indexed = 1,                        \
>>> +        .channel = index,                    \
>>> +        .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |        \
>>> +        IIO_CHAN_INFO_SCALE_SHARED_BIT,                \
>>> +        .address = index,                    \
>>> +        .scan_index = index,                    \
>>> +        .scan_type = {                        \
>>> +            .sign = 'u',                    \
>>> +            .realbits = 12,                    \
>>> +            .storagebits = 16,                \
>>> +            .endianness = IIO_BE,                \
>>> +        },                            \
>>> +    }
>>> +
>>> +static const struct iio_chan_spec ad7923_channels[] = {
>>> +    AD7923_V_CHAN(0),
>>> +    AD7923_V_CHAN(1),
>>> +    AD7923_V_CHAN(2),
>>> +    AD7923_V_CHAN(3),
>>> +    IIO_CHAN_SOFT_TIMESTAMP(4),
>>> +};
>>> +
>>> +/**
>>> + * ad7923_update_scan_mode() setup the spi transfer buffer for the new scan mask
>>> + **/
>>> +static int ad7923_update_scan_mode(struct iio_dev *indio_dev,
>>> +    const unsigned long *active_scan_mask)
>>> +{
>>> +    struct ad7923_state *st = iio_priv(indio_dev);
>>> +    int i, cmd, len;
>>> +
>>> +    len = 0;
>>> +    for_each_set_bit(i, active_scan_mask, AD7923_MAX_CHAN) {
>>> +        cmd = AD7923_WRITE_CR | AD7923_CODING | AD7923_RANGE |
>>> +            AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
>>> +            AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
>>> +            AD7923_CHANNEL_WRITE(i);
>>> +        cmd <<= AD7923_SHIFT_REGISTER;
>>> +        st->tx_buf[len++] = cpu_to_be16(cmd);
>>> +    }
>>> +    /* build spi ring message */
>>> +    st->ring_xfer[0].tx_buf = &st->tx_buf[0];
>>> +    st->ring_xfer[0].len = len;
>>> +    st->ring_xfer[0].cs_change = 1;
>>> +
>>> +    spi_message_init(&st->ring_msg);
>>> +    spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
>>> +
>>> +    for (i = 0; i < len; i++) {
>>> +        st->ring_xfer[i + 1].rx_buf = &st->rx_buf[i];
>>> +        st->ring_xfer[i + 1].len = 2;
>>> +        st->ring_xfer[i + 1].cs_change = 1;
>>> +        spi_message_add_tail(&st->ring_xfer[i + 1], &st->ring_msg);
>>> +    }
>>> +    /* make sure last transfer cs_change is not set */
>>> +    st->ring_xfer[i + 1].cs_change = 0;
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +/**
>>> + * ad7923_trigger_handler() bh of trigger launched polling to ring buffer
>>> + *
>>> + * Currently there is no option in this driver to disable the saving of
>>> + * timestamps within the ring.
>>> + **/
>>> +static irqreturn_t ad7923_trigger_handler(int irq, void *p)
>>> +{
>>> +    struct iio_poll_func *pf = p;
>>> +    struct iio_dev *indio_dev = pf->indio_dev;
>>> +    struct ad7923_state *st = iio_priv(indio_dev);
>>> +    s64 time_ns = 0;
>>> +    int b_sent;
>>> +
>>> +    b_sent = spi_sync(st->spi, &st->ring_msg);
>>> +    if (b_sent)
>>> +        goto done;
>>> +
>>> +    if (indio_dev->scan_timestamp) {
>>> +        time_ns = iio_get_time_ns();
>>> +        memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
>>> +            &time_ns, sizeof(time_ns));
>>> +    }
>>> +
>>> +    iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
>>> +
>>> +done:
>>> +    iio_trigger_notify_done(indio_dev->trig);
>>> +
>>> +    return IRQ_HANDLED;
>>> +}
>>> +
>>> +static int ad7923_scan_direct(struct ad7923_state *st, unsigned ch)
>>> +{
>>> +    int ret, cmd;
>>> +
>>> +    cmd = AD7923_WRITE_CR | AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS) |
>>> +        AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) | AD7923_CODING |
>>> +        AD7923_CHANNEL_WRITE(ch) | AD7923_RANGE;
>>> +    cmd <<= AD7923_SHIFT_REGISTER;
>>> +    st->tx_buf[0] = cpu_to_be16(cmd);
>>> +
>>> +    ret = spi_sync(st->spi, &st->scan_single_msg);
>>> +    if (ret)
>>> +        return ret;
>>> +
>>> +    return be16_to_cpu(st->rx_buf[0]);
>>> +}
>>> +
>>> +static int ad7923_read_raw(struct iio_dev *indio_dev,
>>> +               struct iio_chan_spec const *chan,
>>> +               int *val,
>>> +               int *val2,
>>> +               long m)
>>> +{
>>> +    int ret;
>>> +    struct ad7923_state *st = iio_priv(indio_dev);
>>> +
>>> +    switch (m) {
>>> +    case IIO_CHAN_INFO_RAW:
>>> +        mutex_lock(&indio_dev->mlock);
>>> +        if (iio_buffer_enabled(indio_dev))
>>> +            ret = -EBUSY;
>>> +        else
>>> +            ret = ad7923_scan_direct(st, chan->address);
>>> +        mutex_unlock(&indio_dev->mlock);
>>> +
>>> +        if (ret < 0)
>>> +            return ret;
>>> +
>>> +        if (chan->address == EXTRACT(ret, 12, 4))
>>> +            *val = EXTRACT(ret, 0, 12);
>>> +
>>> +        return IIO_VAL_INT;
>>> +    }
>>> +    return -EINVAL;
>>> +}
>>> +
>>> +static const struct iio_info ad7923_info = {
>>> +    .read_raw = &ad7923_read_raw,
>>> +    .update_scan_mode = ad7923_update_scan_mode,
>>> +    .driver_module = THIS_MODULE,
>>> +};
>>> +
>>> +static int ad7923_probe(struct spi_device *spi)
>>> +{
>>> +    struct ad7923_state *st;
>>> +    struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
>>> +    int ret;
>>> +
>>> +    if (indio_dev == NULL)
>>> +        return -ENOMEM;
>>> +
>>> +    st = iio_priv(indio_dev);
>>> +
>>> +    spi_set_drvdata(spi, indio_dev);
>>> +
>>> +    st->spi = spi;
>>> +
>>> +    indio_dev->name = spi_get_device_id(spi)->name;
>>> +    indio_dev->dev.parent = &spi->dev;
>>> +    indio_dev->modes = INDIO_DIRECT_MODE;
>>> +    indio_dev->channels = ad7923_channels;
>>> +    indio_dev->num_channels = ARRAY_SIZE(ad7923_channels);
>>> +    indio_dev->info = &ad7923_info;
>>> +
>>> +    /* Setup default message */
>>> +
>>> +    st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
>>> +    st->scan_single_xfer[0].len = 2;
>>> +    st->scan_single_xfer[0].cs_change = 1;
>>> +    st->scan_single_xfer[1].rx_buf = &st->rx_buf[0];
>>> +    st->scan_single_xfer[1].len = 2;
>>> +
>>> +    spi_message_init(&st->scan_single_msg);
>>> +    spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
>>> +    spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
>>> +
>>> +    ret = iio_triggered_buffer_setup(indio_dev, NULL,
>>> +            &ad7923_trigger_handler, NULL);
>>> +    if (ret)
>>> +        goto error_free;
>>> +
>>> +    ret = iio_device_register(indio_dev);
>>> +    if (ret)
>>> +        goto error_cleanup_ring;
>>> +
>>> +    return 0;
>>> +
>>> +error_cleanup_ring:
>>> +    iio_triggered_buffer_cleanup(indio_dev);
>>> +error_free:
>>> +    iio_device_free(indio_dev);
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +static int ad7923_remove(struct spi_device *spi)
>>> +{
>>> +    struct iio_dev *indio_dev = spi_get_drvdata(spi);
>>> +
>>> +    iio_device_unregister(indio_dev);
>>> +    iio_triggered_buffer_cleanup(indio_dev);
>>> +    iio_device_free(indio_dev);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static const struct spi_device_id ad7923_id[] = {
>>> +    {"ad7923", 0},
>>> +    {}
>>> +};
>>> +MODULE_DEVICE_TABLE(spi, ad7923_id);
>>> +
>>> +static struct spi_driver ad7923_driver = {
>>> +    .driver = {
>>> +        .name    = "ad7923",
>>> +        .owner    = THIS_MODULE,
>>> +    },
>>> +    .probe        = ad7923_probe,
>>> +    .remove        = ad7923_remove,
>>> +    .id_table    = ad7923_id,
>>> +};
>>> +module_spi_driver(ad7923_driver);
>>> +
>>> +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
>>> +MODULE_AUTHOR("Patrick Vasseur <patrick.vasseur@c-s.fr>");
>>> +MODULE_DESCRIPTION("Analog Devices AD7923 ADC");
>>> +MODULE_LICENSE("GPL v2");
>>> -- 
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>>
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>>
> 
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^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2013-03-03 12:11 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-02-13  6:47 [PATCH v3] IIO ADC support for AD7923 Christophe Leroy
2013-02-13  9:19 ` Lars-Peter Clausen
2013-02-13  9:20   ` Jonathan Cameron
2013-03-03 12:11     ` Jonathan Cameron

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