[PATCH 1/4] Input: ad714xx-spi - force SPI bus into the default 8-bit mode

[PATCH 1/4] Input: ad714xx-spi - force SPI bus into the default 8-bit mode

[Dmitry Torokhov]

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

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
 drivers/input/misc/ad714x-spi.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
index 4120dd5..da83ac9 100644
--- a/drivers/input/misc/ad714x-spi.c
+++ b/drivers/input/misc/ad714x-spi.c
@@ -54,6 +54,12 @@ static int ad714x_spi_write(struct device *dev, unsigned short reg,
 static int __devinit ad714x_spi_probe(struct spi_device *spi)
 {
 	struct ad714x_chip *chip;
+	int err;
+
+	spi->bits_per_word = 8;
+	err = spi_setup(spi);
+	if (err < 0)
+		return err;
 
 	chip = ad714x_probe(&spi->dev, BUS_SPI, spi->irq,
 			    ad714x_spi_read, ad714x_spi_write);
-- 
1.7.6

[PATCH 2/4] Input: ad714x - fix endianness issues

[Dmitry Torokhov]

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

Allow driver to be used on Big Endian boxes.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
 drivers/input/misc/ad714x-i2c.c |   34 ++++++++++------------------------
 drivers/input/misc/ad714x-spi.c |   24 +++++++++++++++---------
 2 files changed, 25 insertions(+), 33 deletions(-)

diff --git a/drivers/input/misc/ad714x-i2c.c b/drivers/input/misc/ad714x-i2c.c
index e21deb1..00a6a22 100644
--- a/drivers/input/misc/ad714x-i2c.c
+++ b/drivers/input/misc/ad714x-i2c.c
@@ -32,17 +32,12 @@ static int ad714x_i2c_write(struct device *dev, unsigned short reg,
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	int ret = 0;
-	u8 *_reg = (u8 *)&reg;
-	u8 *_data = (u8 *)&data;
-
-	u8 tx[4] = {
-		_reg[1],
-		_reg[0],
-		_data[1],
-		_data[0]
+	unsigned short tx[2] = {
+		cpu_to_be16(reg),
+		cpu_to_be16(data)
 	};
 
-	ret = i2c_master_send(client, tx, 4);
+	ret = i2c_master_send(client, (u8 *)tx, 4);
 	if (ret < 0)
 		dev_err(&client->dev, "I2C write error\n");
 
@@ -54,25 +49,16 @@ static int ad714x_i2c_read(struct device *dev, unsigned short reg,
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	int ret = 0;
-	u8 *_reg = (u8 *)&reg;
-	u8 *_data = (u8 *)data;
+	unsigned short tx = cpu_to_be16(reg);
 
-	u8 tx[2] = {
-		_reg[1],
-		_reg[0]
-	};
-	u8 rx[2];
-
-	ret = i2c_master_send(client, tx, 2);
+	ret = i2c_master_send(client, (u8 *)&tx, 2);
 	if (ret >= 0)
-		ret = i2c_master_recv(client, rx, 2);
+		ret = i2c_master_recv(client, (u8 *)data, 2);
 
-	if (unlikely(ret < 0)) {
+	if (unlikely(ret < 0))
 		dev_err(&client->dev, "I2C read error\n");
-	} else {
-		_data[0] = rx[1];
-		_data[1] = rx[0];
-	}
+	else
+		*data = be16_to_cpu(*data);
 
 	return ret;
 }
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
index da83ac9..0c7f948 100644
--- a/drivers/input/misc/ad714x-spi.c
+++ b/drivers/input/misc/ad714x-spi.c
@@ -6,7 +6,7 @@
  * Licensed under the GPL-2 or later.
  */
 
-#include <linux/input.h>	/* BUS_I2C */
+#include <linux/input.h>	/* BUS_SPI */
 #include <linux/module.h>
 #include <linux/spi/spi.h>
 #include <linux/pm.h>
@@ -30,22 +30,28 @@ static int ad714x_spi_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);
 
-static int ad714x_spi_read(struct device *dev, unsigned short reg,
-		unsigned short *data)
+static int ad714x_spi_read(struct device *dev,
+			   unsigned short reg, unsigned short *data)
 {
 	struct spi_device *spi = to_spi_device(dev);
-	unsigned short tx = AD714x_SPI_CMD_PREFIX | AD714x_SPI_READ | reg;
+	unsigned short tx = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
+					AD714x_SPI_READ | reg);
+	int ret;
 
-	return spi_write_then_read(spi, (u8 *)&tx, 2, (u8 *)data, 2);
+	ret = spi_write_then_read(spi, &tx, 2, data, 2);
+
+	*data = be16_to_cpup(data);
+
+	return ret;
 }
 
-static int ad714x_spi_write(struct device *dev, unsigned short reg,
-		unsigned short data)
+static int ad714x_spi_write(struct device *dev,
+			    unsigned short reg, unsigned short data)
 {
 	struct spi_device *spi = to_spi_device(dev);
 	unsigned short tx[2] = {
-		AD714x_SPI_CMD_PREFIX | reg,
-		data
+		cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg),
+		cpu_to_be16(data)
 	};
 
 	return spi_write(spi, (u8 *)tx, 4);
-- 
1.7.6

Re: [PATCH 2/4] Input: ad714x - fix endianness issues

[Mark Brown]

On Sun, Aug 21, 2011 at 01:09:03PM -0700, Dmitry Torokhov wrote:
> From: Michael Hennerich <michael.hennerich@analog.com>
> 
> Allow driver to be used on Big Endian boxes.
> 
> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Might the regmap API be helpful here?

Re: [PATCH 2/4] Input: ad714x - fix endianness issues

[Dmitry Torokhov]

On Tue, Aug 23, 2011 at 05:22:57PM +0100, Mark Brown wrote:
> On Sun, Aug 21, 2011 at 01:09:03PM -0700, Dmitry Torokhov wrote:
> > From: Michael Hennerich <michael.hennerich@analog.com>
> > 
> > Allow driver to be used on Big Endian boxes.
> > 
> > Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
> > Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
> 
> Might the regmap API be helpful here?

Looks like it might ;)... But as a follow-up for 3.2.

Thanks.

-- 
Dmitry

[PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Dmitry Torokhov]

spi_write() requires use of DMA-safe (cacheline aligned) buffers.
Also use the same buffers when reading data since to avoid extra
locking and potential memory allocation in spi_write_then_read().

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
 drivers/input/misc/ad714x-i2c.c |   60 ++++++++++++++------------
 drivers/input/misc/ad714x-spi.c |   51 ++++++++++++++++------
 drivers/input/misc/ad714x.c     |   90 +++++++++++++--------------------------
 drivers/input/misc/ad714x.h     |   33 +++++++++++++-
 4 files changed, 131 insertions(+), 103 deletions(-)

diff --git a/drivers/input/misc/ad714x-i2c.c b/drivers/input/misc/ad714x-i2c.c
index 00a6a22..6c61218 100644
--- a/drivers/input/misc/ad714x-i2c.c
+++ b/drivers/input/misc/ad714x-i2c.c
@@ -27,40 +27,46 @@ static int ad714x_i2c_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);
 
-static int ad714x_i2c_write(struct device *dev, unsigned short reg,
-				unsigned short data)
+static int ad714x_i2c_write(struct ad714x_chip *chip,
+			    unsigned short reg, unsigned short data)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	int ret = 0;
-	unsigned short tx[2] = {
-		cpu_to_be16(reg),
-		cpu_to_be16(data)
-	};
-
-	ret = i2c_master_send(client, (u8 *)tx, 4);
-	if (ret < 0)
-		dev_err(&client->dev, "I2C write error\n");
-
-	return ret;
+	struct i2c_client *client = to_i2c_client(chip->dev);
+	int error;
+
+	chip->xfer_buf[0] = cpu_to_be16(reg);
+	chip->xfer_buf[1] = cpu_to_be16(data);
+
+	error = i2c_master_send(client, (u8 *)chip->xfer_buf,
+				2 * sizeof(*chip->xfer_buf));
+	if (unlikely(error < 0)) {
+		dev_err(&client->dev, "I2C write error: %d\n", error);
+		return error;
+	}
+
+	return 0;
 }
 
-static int ad714x_i2c_read(struct device *dev, unsigned short reg,
-				unsigned short *data)
+static int ad714x_i2c_read(struct ad714x_chip *chip,
+			   unsigned short reg, unsigned short *data)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	int ret = 0;
-	unsigned short tx = cpu_to_be16(reg);
+	struct i2c_client *client = to_i2c_client(chip->dev);
+	int error;
+
+	chip->xfer_buf[0] = cpu_to_be16(reg);
 
-	ret = i2c_master_send(client, (u8 *)&tx, 2);
-	if (ret >= 0)
-		ret = i2c_master_recv(client, (u8 *)data, 2);
+	error = i2c_master_send(client, (u8 *)chip->xfer_buf,
+				sizeof(*chip->xfer_buf));
+	if (error >= 0)
+		error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
+					sizeof(*chip->xfer_buf));
 
-	if (unlikely(ret < 0))
-		dev_err(&client->dev, "I2C read error\n");
-	else
-		*data = be16_to_cpu(*data);
+	if (unlikely(error < 0)) {
+		dev_err(&client->dev, "I2C read error: %d\n", error);
+		return error;
+	}
 
-	return ret;
+	*data = be16_to_cpup(chip->xfer_buf);
+	return 0;
 }
 
 static int __devinit ad714x_i2c_probe(struct i2c_client *client,
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
index 0c7f948..306577d 100644
--- a/drivers/input/misc/ad714x-spi.c
+++ b/drivers/input/misc/ad714x-spi.c
@@ -30,31 +30,54 @@ static int ad714x_spi_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);
 
-static int ad714x_spi_read(struct device *dev,
+static int ad714x_spi_read(struct ad714x_chip *chip,
 			   unsigned short reg, unsigned short *data)
 {
-	struct spi_device *spi = to_spi_device(dev);
-	unsigned short tx = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
+	struct spi_device *spi = to_spi_device(chip->dev);
+	struct spi_message message;
+	struct spi_transfer xfer[2];
+	int error;
+
+	spi_message_init(&message);
+	memset(xfer, 0, sizeof(xfer));
+
+	chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
 					AD714x_SPI_READ | reg);
-	int ret;
+	xfer[0].tx_buf = &chip->xfer_buf[0];
+	xfer[0].len = sizeof(chip->xfer_buf[0]);
+	spi_message_add_tail(&xfer[0], &message);
 
-	ret = spi_write_then_read(spi, &tx, 2, data, 2);
+	xfer[1].rx_buf = &chip->xfer_buf[1];
+	xfer[1].len = sizeof(chip->xfer_buf[1]);
+	spi_message_add_tail(&xfer[1], &message);
 
-	*data = be16_to_cpup(data);
+	error = spi_sync(spi, &message);
+	if (unlikely(error)) {
+		dev_err(chip->dev, "SPI read error: %d\n", error);
+		return error;
+	}
 
-	return ret;
+	*data = be16_to_cpu(chip->xfer_buf[1]);
+	return 0;
 }
 
-static int ad714x_spi_write(struct device *dev,
+static int ad714x_spi_write(struct ad714x_chip *chip,
 			    unsigned short reg, unsigned short data)
 {
-	struct spi_device *spi = to_spi_device(dev);
-	unsigned short tx[2] = {
-		cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg),
-		cpu_to_be16(data)
-	};
+	struct spi_device *spi = to_spi_device(chip->dev);
+	int error;
 
-	return spi_write(spi, (u8 *)tx, 4);
+	chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg);
+	chip->xfer_buf[1] = cpu_to_be16(data);
+
+	error = spi_write(spi, (u8 *)chip->xfer_buf,
+			  2 * sizeof(*chip->xfer_buf));
+	if (unlikely(error)) {
+		dev_err(chip->dev, "SPI write error: %d\n", error);
+		return error;
+	}
+
+	return 0;
 }
 
 static int __devinit ad714x_spi_probe(struct spi_device *spi)
diff --git a/drivers/input/misc/ad714x.c b/drivers/input/misc/ad714x.c
index c3a62c4..2be0366 100644
--- a/drivers/input/misc/ad714x.c
+++ b/drivers/input/misc/ad714x.c
@@ -59,7 +59,6 @@
 #define STAGE11_AMBIENT		0x27D
 
 #define PER_STAGE_REG_NUM      36
-#define STAGE_NUM              12
 #define STAGE_CFGREG_NUM       8
 #define SYS_CFGREG_NUM         8
 
@@ -124,28 +123,6 @@ struct ad714x_driver_data {
  * information to integrate all things which will be private data
  * of spi/i2c device
  */
-struct ad714x_chip {
-	unsigned short h_state;
-	unsigned short l_state;
-	unsigned short c_state;
-	unsigned short adc_reg[STAGE_NUM];
-	unsigned short amb_reg[STAGE_NUM];
-	unsigned short sensor_val[STAGE_NUM];
-
-	struct ad714x_platform_data *hw;
-	struct ad714x_driver_data *sw;
-
-	int irq;
-	struct device *dev;
-	ad714x_read_t read;
-	ad714x_write_t write;
-
-	struct mutex mutex;
-
-	unsigned product;
-	unsigned version;
-};
-
 static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 				int start_stage, int end_stage)
 {
@@ -154,13 +131,13 @@ static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 
 	mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 
-	ad714x->read(ad714x->dev, STG_COM_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
 	data |= 1 << end_stage;
-	ad714x->write(ad714x->dev, STG_COM_INT_EN_REG, data);
+	ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 
-	ad714x->read(ad714x->dev, STG_HIGH_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
 	data &= ~mask;
-	ad714x->write(ad714x->dev, STG_HIGH_INT_EN_REG, data);
+	ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 }
 
 static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
@@ -171,13 +148,13 @@ static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
 
 	mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 
-	ad714x->read(ad714x->dev, STG_COM_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
 	data &= ~(1 << end_stage);
-	ad714x->write(ad714x->dev, STG_COM_INT_EN_REG, data);
+	ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 
-	ad714x->read(ad714x->dev, STG_HIGH_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
 	data |= mask;
-	ad714x->write(ad714x->dev, STG_HIGH_INT_EN_REG, data);
+	ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 }
 
 static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
@@ -274,10 +251,8 @@ static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 	int i;
 
 	for (i = hw->start_stage; i <= hw->end_stage; i++) {
-		ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
-			&ad714x->adc_reg[i]);
-		ad714x->read(ad714x->dev,
-				STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
+		ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
+		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 				&ad714x->amb_reg[i]);
 
 		ad714x->sensor_val[i] = abs(ad714x->adc_reg[i] -
@@ -445,10 +420,8 @@ static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 	int i;
 
 	for (i = hw->start_stage; i <= hw->end_stage; i++) {
-		ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
-			&ad714x->adc_reg[i]);
-		ad714x->read(ad714x->dev,
-				STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
+		ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
+		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 				&ad714x->amb_reg[i]);
 		if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
 			ad714x->sensor_val[i] = ad714x->adc_reg[i] -
@@ -598,10 +571,8 @@ static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 	int i;
 
 	for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
-		ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
-				&ad714x->adc_reg[i]);
-		ad714x->read(ad714x->dev,
-				STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
+		ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
+		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 				&ad714x->amb_reg[i]);
 		if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
 			ad714x->sensor_val[i] = ad714x->adc_reg[i] -
@@ -891,7 +862,7 @@ static int ad714x_hw_detect(struct ad714x_chip *ad714x)
 {
 	unsigned short data;
 
-	ad714x->read(ad714x->dev, AD714X_PARTID_REG, &data);
+	ad714x->read(ad714x, AD714X_PARTID_REG, &data);
 	switch (data & 0xFFF0) {
 	case AD7142_PARTID:
 		ad714x->product = 0x7142;
@@ -940,23 +911,22 @@ static void ad714x_hw_init(struct ad714x_chip *ad714x)
 	for (i = 0; i < STAGE_NUM; i++) {
 		reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
 		for (j = 0; j < STAGE_CFGREG_NUM; j++)
-			ad714x->write(ad714x->dev, reg_base + j,
+			ad714x->write(ad714x, reg_base + j,
 					ad714x->hw->stage_cfg_reg[i][j]);
 	}
 
 	for (i = 0; i < SYS_CFGREG_NUM; i++)
-		ad714x->write(ad714x->dev, AD714X_SYSCFG_REG + i,
+		ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
 			ad714x->hw->sys_cfg_reg[i]);
 	for (i = 0; i < SYS_CFGREG_NUM; i++)
-		ad714x->read(ad714x->dev, AD714X_SYSCFG_REG + i,
-			&data);
+		ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data);
 
-	ad714x->write(ad714x->dev, AD714X_STG_CAL_EN_REG, 0xFFF);
+	ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
 
 	/* clear all interrupts */
-	ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG, &data);
-	ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG, &data);
-	ad714x->read(ad714x->dev, STG_COM_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
 }
 
 static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
@@ -966,9 +936,9 @@ static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
 
 	mutex_lock(&ad714x->mutex);
 
-	ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG, &ad714x->l_state);
-	ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG, &ad714x->h_state);
-	ad714x->read(ad714x->dev, STG_COM_INT_STA_REG, &ad714x->c_state);
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state);
+	ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &ad714x->h_state);
+	ad714x->read(ad714x, STG_COM_INT_STA_REG, &ad714x->c_state);
 
 	for (i = 0; i < ad714x->hw->button_num; i++)
 		ad714x_button_state_machine(ad714x, i);
@@ -1245,7 +1215,7 @@ int ad714x_disable(struct ad714x_chip *ad714x)
 	mutex_lock(&ad714x->mutex);
 
 	data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
-	ad714x->write(ad714x->dev, AD714X_PWR_CTRL, data);
+	ad714x->write(ad714x, AD714X_PWR_CTRL, data);
 
 	mutex_unlock(&ad714x->mutex);
 
@@ -1263,16 +1233,16 @@ int ad714x_enable(struct ad714x_chip *ad714x)
 
 	/* resume to non-shutdown mode */
 
-	ad714x->write(ad714x->dev, AD714X_PWR_CTRL,
+	ad714x->write(ad714x, AD714X_PWR_CTRL,
 			ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
 
 	/* make sure the interrupt output line is not low level after resume,
 	 * otherwise we will get no chance to enter falling-edge irq again
 	 */
 
-	ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG, &data);
-	ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG, &data);
-	ad714x->read(ad714x->dev, STG_COM_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
 
 	mutex_unlock(&ad714x->mutex);
 
diff --git a/drivers/input/misc/ad714x.h b/drivers/input/misc/ad714x.h
index 45c54fb..d12d149 100644
--- a/drivers/input/misc/ad714x.h
+++ b/drivers/input/misc/ad714x.h
@@ -11,11 +11,40 @@
 
 #include <linux/types.h>
 
+#define STAGE_NUM              12
+
 struct device;
+struct ad714x_platform_data;
+struct ad714x_driver_data;
 struct ad714x_chip;
 
-typedef int (*ad714x_read_t)(struct device *, unsigned short, unsigned short *);
-typedef int (*ad714x_write_t)(struct device *, unsigned short, unsigned short);
+typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *);
+typedef int (*ad714x_write_t)(struct ad714x_chip *, unsigned short, unsigned short);
+
+struct ad714x_chip {
+	unsigned short h_state;
+	unsigned short l_state;
+	unsigned short c_state;
+	unsigned short adc_reg[STAGE_NUM];
+	unsigned short amb_reg[STAGE_NUM];
+	unsigned short sensor_val[STAGE_NUM];
+
+	struct ad714x_platform_data *hw;
+	struct ad714x_driver_data *sw;
+
+	int irq;
+	struct device *dev;
+	ad714x_read_t read;
+	ad714x_write_t write;
+
+	struct mutex mutex;
+
+	unsigned product;
+	unsigned version;
+
+	__be16 xfer_buf[16] ____cacheline_aligned;
+
+};
 
 int ad714x_disable(struct ad714x_chip *ad714x);
 int ad714x_enable(struct ad714x_chip *ad714x);
-- 
1.7.6

Re: [Device-drivers-devel] [PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Mike Frysinger]

On Sun, Aug 21, 2011 at 16:09, Dmitry Torokhov wrote:
> spi_write() requires use of DMA-safe (cacheline aligned) buffers.
> Also use the same buffers when reading data since to avoid extra
> locking and potential memory allocation in spi_write_then_read().

seems like there's a whole lot of style changes unrelated to spi and
dma ... more so than the actual dma/spi change.
-mike

Re: [Device-drivers-devel] [PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Dmitry Torokhov]

ike Frysinger <vapier.adi@gmail.com> wrote:

>On Sun, Aug 21, 2011 at 16:09, Dmitry Torokhov wrote:
>> spi_write() requires use of DMA-safe (cacheline aligned) buffers.
>> Also use the same buffers when reading data since to avoid extra
>> locking and potential memory allocation in spi_write_then_read().
>
>seems like there's a whole lot of style changes unrelated to spi and
>dma ... more so than the actual dma/spi change.

Hmm, I tried to control myself so (aside of return -> error) renames there shouldn't be many style changes... The diff looks big because we are passing ad714x instead of ad714x->dev to the read/write methods. 

-- 
Dmitry

Re: [Device-drivers-devel] [PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Dmitry Torokhov]

ike Frysinger <vapier.adi@gmail.com> wrote:

>On Sun, Aug 21, 2011 at 16:09, Dmitry Torokhov wrote:
>> spi_write() requires use of DMA-safe (cacheline aligned) buffers.
>> Also use the same buffers when reading data since to avoid extra
>> locking and potential memory allocation in spi_write_then_read().
>
>seems like there's a whole lot of style changes unrelated to spi and
>dma ... more so than the actual dma/spi change.

Hmm, I tried to control myself so (aside of return -> error) renames there shouldn't be many style changes... The diff looks big because we are passing ad714x instead of ad714x->dev to the read/write methods. 

-- 
Dmitry

Re: [PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Michael Hennerich]

On 08/21/2011 10:09 PM, Dmitry Torokhov wrote:
> spi_write() requires use of DMA-safe (cacheline aligned) buffers.
> Also use the same buffers when reading data since to avoid extra
> locking and potential memory allocation in spi_write_then_read().
>
> Signed-off-by: Dmitry Torokhov<dtor@mail.ru>
Looks good - one piece of the original patch set got lost.
See below - patch follows.

Thanks!

Acked-by: Michael Hennerich <michael.hennerich@analog.com>

> ---
>   drivers/input/misc/ad714x-i2c.c |   60 ++++++++++++++------------
>   drivers/input/misc/ad714x-spi.c |   51 ++++++++++++++++------
>   drivers/input/misc/ad714x.c     |   90 +++++++++++++--------------------------
>   drivers/input/misc/ad714x.h     |   33 +++++++++++++-
>   4 files changed, 131 insertions(+), 103 deletions(-)
>
> diff --git a/drivers/input/misc/ad714x-i2c.c b/drivers/input/misc/ad714x-i2c.c
> index 00a6a22..6c61218 100644
> --- a/drivers/input/misc/ad714x-i2c.c
> +++ b/drivers/input/misc/ad714x-i2c.c
> @@ -27,40 +27,46 @@ static int ad714x_i2c_resume(struct device *dev)
>
>   static SIMPLE_DEV_PM_OPS(ad714x_i2c_pm, ad714x_i2c_suspend, ad714x_i2c_resume);
>
> -static int ad714x_i2c_write(struct device *dev, unsigned short reg,
> -                               unsigned short data)
> +static int ad714x_i2c_write(struct ad714x_chip *chip,
> +                           unsigned short reg, unsigned short data)
>   {
> -       struct i2c_client *client = to_i2c_client(dev);
> -       int ret = 0;
> -       unsigned short tx[2] = {
> -               cpu_to_be16(reg),
> -               cpu_to_be16(data)
> -       };
> -
> -       ret = i2c_master_send(client, (u8 *)tx, 4);
> -       if (ret<  0)
> -               dev_err(&client->dev, "I2C write error\n");
> -
> -       return ret;
> +       struct i2c_client *client = to_i2c_client(chip->dev);
> +       int error;
> +
> +       chip->xfer_buf[0] = cpu_to_be16(reg);
> +       chip->xfer_buf[1] = cpu_to_be16(data);
> +
> +       error = i2c_master_send(client, (u8 *)chip->xfer_buf,
> +                               2 * sizeof(*chip->xfer_buf));
> +       if (unlikely(error<  0)) {
> +               dev_err(&client->dev, "I2C write error: %d\n", error);
> +               return error;
> +       }
> +
> +       return 0;
>   }
>
> -static int ad714x_i2c_read(struct device *dev, unsigned short reg,
> -                               unsigned short *data)
> +static int ad714x_i2c_read(struct ad714x_chip *chip,
> +                          unsigned short reg, unsigned short *data)
>   {
> -       struct i2c_client *client = to_i2c_client(dev);
> -       int ret = 0;
> -       unsigned short tx = cpu_to_be16(reg);
> +       struct i2c_client *client = to_i2c_client(chip->dev);
> +       int error;
> +
> +       chip->xfer_buf[0] = cpu_to_be16(reg);
>
> -       ret = i2c_master_send(client, (u8 *)&tx, 2);
> -       if (ret>= 0)
> -               ret = i2c_master_recv(client, (u8 *)data, 2);
> +       error = i2c_master_send(client, (u8 *)chip->xfer_buf,
> +                               sizeof(*chip->xfer_buf));
> +       if (error>= 0)
> +               error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
> +                                       sizeof(*chip->xfer_buf));
>
> -       if (unlikely(ret<  0))
> -               dev_err(&client->dev, "I2C read error\n");
> -       else
> -               *data = be16_to_cpu(*data);
> +       if (unlikely(error<  0)) {
> +               dev_err(&client->dev, "I2C read error: %d\n", error);
> +               return error;
> +       }
>
> -       return ret;
> +       *data = be16_to_cpup(chip->xfer_buf);
> +       return 0;
>   }
>
>   static int __devinit ad714x_i2c_probe(struct i2c_client *client,
> diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
> index 0c7f948..306577d 100644
> --- a/drivers/input/misc/ad714x-spi.c
> +++ b/drivers/input/misc/ad714x-spi.c
> @@ -30,31 +30,54 @@ static int ad714x_spi_resume(struct device *dev)
>
>   static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);
>
> -static int ad714x_spi_read(struct device *dev,
> +static int ad714x_spi_read(struct ad714x_chip *chip,
>                             unsigned short reg, unsigned short *data)
>   {
> -       struct spi_device *spi = to_spi_device(dev);
> -       unsigned short tx = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
> +       struct spi_device *spi = to_spi_device(chip->dev);
> +       struct spi_message message;
> +       struct spi_transfer xfer[2];
> +       int error;
> +
> +       spi_message_init(&message);
> +       memset(xfer, 0, sizeof(xfer));
> +
> +       chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX |
>                                          AD714x_SPI_READ | reg);
> -       int ret;
> +       xfer[0].tx_buf =&chip->xfer_buf[0];
> +       xfer[0].len = sizeof(chip->xfer_buf[0]);
> +       spi_message_add_tail(&xfer[0],&message);
>
> -       ret = spi_write_then_read(spi,&tx, 2, data, 2);
> +       xfer[1].rx_buf =&chip->xfer_buf[1];
> +       xfer[1].len = sizeof(chip->xfer_buf[1]);
> +       spi_message_add_tail(&xfer[1],&message);
>
> -       *data = be16_to_cpup(data);
> +       error = spi_sync(spi,&message);
> +       if (unlikely(error)) {
> +               dev_err(chip->dev, "SPI read error: %d\n", error);
> +               return error;
> +       }
>
> -       return ret;
> +       *data = be16_to_cpu(chip->xfer_buf[1]);
> +       return 0;
>   }
>
> -static int ad714x_spi_write(struct device *dev,
> +static int ad714x_spi_write(struct ad714x_chip *chip,
>                              unsigned short reg, unsigned short data)
>   {
> -       struct spi_device *spi = to_spi_device(dev);
> -       unsigned short tx[2] = {
> -               cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg),
> -               cpu_to_be16(data)
> -       };
> +       struct spi_device *spi = to_spi_device(chip->dev);
> +       int error;
>
> -       return spi_write(spi, (u8 *)tx, 4);
> +       chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg);
> +       chip->xfer_buf[1] = cpu_to_be16(data);
> +
> +       error = spi_write(spi, (u8 *)chip->xfer_buf,
> +                         2 * sizeof(*chip->xfer_buf));
> +       if (unlikely(error)) {
> +               dev_err(chip->dev, "SPI write error: %d\n", error);
> +               return error;
> +       }
> +
> +       return 0;
>   }
>
>   static int __devinit ad714x_spi_probe(struct spi_device *spi)
> diff --git a/drivers/input/misc/ad714x.c b/drivers/input/misc/ad714x.c
> index c3a62c4..2be0366 100644
> --- a/drivers/input/misc/ad714x.c
> +++ b/drivers/input/misc/ad714x.c
> @@ -59,7 +59,6 @@
>   #define STAGE11_AMBIENT                0x27D
>
>   #define PER_STAGE_REG_NUM      36
> -#define STAGE_NUM              12
>   #define STAGE_CFGREG_NUM       8
>   #define SYS_CFGREG_NUM         8
>
> @@ -124,28 +123,6 @@ struct ad714x_driver_data {
>    * information to integrate all things which will be private data
>    * of spi/i2c device
>    */
> -struct ad714x_chip {
> -       unsigned short h_state;
> -       unsigned short l_state;
> -       unsigned short c_state;
> -       unsigned short adc_reg[STAGE_NUM];
> -       unsigned short amb_reg[STAGE_NUM];
> -       unsigned short sensor_val[STAGE_NUM];
> -
> -       struct ad714x_platform_data *hw;
> -       struct ad714x_driver_data *sw;
> -
> -       int irq;
> -       struct device *dev;
> -       ad714x_read_t read;
> -       ad714x_write_t write;
> -
> -       struct mutex mutex;
> -
> -       unsigned product;
> -       unsigned version;
> -};
> -
>   static void ad714x_use_com_int(struct ad714x_chip *ad714x,
>                                  int start_stage, int end_stage)
>   {
> @@ -154,13 +131,13 @@ static void ad714x_use_com_int(struct ad714x_chip *ad714x,
>
>          mask = ((1<<  (end_stage + 1)) - 1) - ((1<<  start_stage) - 1);
>
> -       ad714x->read(ad714x->dev, STG_COM_INT_EN_REG,&data);
> +       ad714x->read(ad714x, STG_COM_INT_EN_REG,&data);
>          data |= 1<<  end_stage;
> -       ad714x->write(ad714x->dev, STG_COM_INT_EN_REG, data);
> +       ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
>
> -       ad714x->read(ad714x->dev, STG_HIGH_INT_EN_REG,&data);
> +       ad714x->read(ad714x, STG_HIGH_INT_EN_REG,&data);
>          data&= ~mask;
> -       ad714x->write(ad714x->dev, STG_HIGH_INT_EN_REG, data);
> +       ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
>   }
>
>   static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
> @@ -171,13 +148,13 @@ static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
>
>          mask = ((1<<  (end_stage + 1)) - 1) - ((1<<  start_stage) - 1);
>
> -       ad714x->read(ad714x->dev, STG_COM_INT_EN_REG,&data);
> +       ad714x->read(ad714x, STG_COM_INT_EN_REG,&data);
>          data&= ~(1<<  end_stage);
> -       ad714x->write(ad714x->dev, STG_COM_INT_EN_REG, data);
> +       ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
>
> -       ad714x->read(ad714x->dev, STG_HIGH_INT_EN_REG,&data);
> +       ad714x->read(ad714x, STG_HIGH_INT_EN_REG,&data);
>          data |= mask;
> -       ad714x->write(ad714x->dev, STG_HIGH_INT_EN_REG, data);
> +       ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
>   }
>
>   static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
> @@ -274,10 +251,8 @@ static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
>          int i;
>
>          for (i = hw->start_stage; i<= hw->end_stage; i++) {
> -               ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
> -&ad714x->adc_reg[i]);
> -               ad714x->read(ad714x->dev,
> -                               STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
> +               ad714x->read(ad714x, CDC_RESULT_S0 + i,&ad714x->adc_reg[i]);
> +               ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
>                                  &ad714x->amb_reg[i]);
>
>                  ad714x->sensor_val[i] = abs(ad714x->adc_reg[i] -
> @@ -445,10 +420,8 @@ static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
>          int i;
>
>          for (i = hw->start_stage; i<= hw->end_stage; i++) {
> -               ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
> -&ad714x->adc_reg[i]);
> -               ad714x->read(ad714x->dev,
> -                               STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
> +               ad714x->read(ad714x, CDC_RESULT_S0 + i,&ad714x->adc_reg[i]);
> +               ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
>                                  &ad714x->amb_reg[i]);
>                  if (ad714x->adc_reg[i]>  ad714x->amb_reg[i])
>                          ad714x->sensor_val[i] = ad714x->adc_reg[i] -
> @@ -598,10 +571,8 @@ static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
>          int i;
>
>          for (i = hw->x_start_stage; i<= hw->x_end_stage; i++) {
> -               ad714x->read(ad714x->dev, CDC_RESULT_S0 + i,
> -&ad714x->adc_reg[i]);
> -               ad714x->read(ad714x->dev,
> -                               STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
> +               ad714x->read(ad714x, CDC_RESULT_S0 + i,&ad714x->adc_reg[i]);
> +               ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
>                                  &ad714x->amb_reg[i]);
>                  if (ad714x->adc_reg[i]>  ad714x->amb_reg[i])
>                          ad714x->sensor_val[i] = ad714x->adc_reg[i] -
> @@ -891,7 +862,7 @@ static int ad714x_hw_detect(struct ad714x_chip *ad714x)
>   {
>          unsigned short data;
>
> -       ad714x->read(ad714x->dev, AD714X_PARTID_REG,&data);
> +       ad714x->read(ad714x, AD714X_PARTID_REG,&data);
>          switch (data&  0xFFF0) {
>          case AD7142_PARTID:
>                  ad714x->product = 0x7142;
> @@ -940,23 +911,22 @@ static void ad714x_hw_init(struct ad714x_chip *ad714x)
>          for (i = 0; i<  STAGE_NUM; i++) {
>                  reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
>                  for (j = 0; j<  STAGE_CFGREG_NUM; j++)
> -                       ad714x->write(ad714x->dev, reg_base + j,
> +                       ad714x->write(ad714x, reg_base + j,
>                                          ad714x->hw->stage_cfg_reg[i][j]);
>          }
>
>          for (i = 0; i<  SYS_CFGREG_NUM; i++)
> -               ad714x->write(ad714x->dev, AD714X_SYSCFG_REG + i,
> +               ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
>                          ad714x->hw->sys_cfg_reg[i]);
>          for (i = 0; i<  SYS_CFGREG_NUM; i++)
> -               ad714x->read(ad714x->dev, AD714X_SYSCFG_REG + i,
> -&data);
> +               ad714x->read(ad714x, AD714X_SYSCFG_REG + i,&data);
>
> -       ad714x->write(ad714x->dev, AD714X_STG_CAL_EN_REG, 0xFFF);
> +       ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
>
>          /* clear all interrupts */
> -       ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG,&data);
> -       ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG,&data);
> -       ad714x->read(ad714x->dev, STG_COM_INT_STA_REG,&data);
> +       ad714x->read(ad714x, STG_LOW_INT_STA_REG,&data);
> +       ad714x->read(ad714x, STG_HIGH_INT_STA_REG,&data);
> +       ad714x->read(ad714x, STG_COM_INT_STA_REG,&data);
>   }
>
>   static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
> @@ -966,9 +936,9 @@ static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
>
>          mutex_lock(&ad714x->mutex);
>
> -       ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG,&ad714x->l_state);
> -       ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG,&ad714x->h_state);
> -       ad714x->read(ad714x->dev, STG_COM_INT_STA_REG,&ad714x->c_state);
> +       ad714x->read(ad714x, STG_LOW_INT_STA_REG,&ad714x->l_state);
> +       ad714x->read(ad714x, STG_HIGH_INT_STA_REG,&ad714x->h_state);
> +       ad714x->read(ad714x, STG_COM_INT_STA_REG,&ad714x->c_state);
>
>          for (i = 0; i<  ad714x->hw->button_num; i++)
>                  ad714x_button_state_machine(ad714x, i);
> @@ -1245,7 +1215,7 @@ int ad714x_disable(struct ad714x_chip *ad714x)
>          mutex_lock(&ad714x->mutex);
>
>          data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
> -       ad714x->write(ad714x->dev, AD714X_PWR_CTRL, data);
> +       ad714x->write(ad714x, AD714X_PWR_CTRL, data);
>
>          mutex_unlock(&ad714x->mutex);
>
> @@ -1263,16 +1233,16 @@ int ad714x_enable(struct ad714x_chip *ad714x)
>
>          /* resume to non-shutdown mode */
>
> -       ad714x->write(ad714x->dev, AD714X_PWR_CTRL,
> +       ad714x->write(ad714x, AD714X_PWR_CTRL,
>                          ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
>
>          /* make sure the interrupt output line is not low level after resume,
>           * otherwise we will get no chance to enter falling-edge irq again
>           */
>
> -       ad714x->read(ad714x->dev, STG_LOW_INT_STA_REG,&data);
> -       ad714x->read(ad714x->dev, STG_HIGH_INT_STA_REG,&data);
> -       ad714x->read(ad714x->dev, STG_COM_INT_STA_REG,&data);
> +       ad714x->read(ad714x, STG_LOW_INT_STA_REG,&data);
> +       ad714x->read(ad714x, STG_HIGH_INT_STA_REG,&data);
> +       ad714x->read(ad714x, STG_COM_INT_STA_REG,&data);
>
>          mutex_unlock(&ad714x->mutex);
>
> diff --git a/drivers/input/misc/ad714x.h b/drivers/input/misc/ad714x.h
> index 45c54fb..d12d149 100644
> --- a/drivers/input/misc/ad714x.h
> +++ b/drivers/input/misc/ad714x.h
> @@ -11,11 +11,40 @@
>
>   #include<linux/types.h>
>
> +#define STAGE_NUM              12
> +
>   struct device;
> +struct ad714x_platform_data;
> +struct ad714x_driver_data;
>   struct ad714x_chip;
>
> -typedef int (*ad714x_read_t)(struct device *, unsigned short, unsigned short *);
> -typedef int (*ad714x_write_t)(struct device *, unsigned short, unsigned short);
> +typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *);
> +typedef int (*ad714x_write_t)(struct ad714x_chip *, unsigned short, unsigned short);
> +
> +struct ad714x_chip {
> +       unsigned short h_state;
> +       unsigned short l_state;
Since we read status interrupt registers in row, we also need to place the
storage members sequentially. This part got dropped from the original 
patch set.
Patch follows.


> +       unsigned short c_state;
> +       unsigned short adc_reg[STAGE_NUM];
> +       unsigned short amb_reg[STAGE_NUM];
> +       unsigned short sensor_val[STAGE_NUM];
> +
> +       struct ad714x_platform_data *hw;
> +       struct ad714x_driver_data *sw;
> +
> +       int irq;
> +       struct device *dev;
> +       ad714x_read_t read;
> +       ad714x_write_t write;
> +
> +       struct mutex mutex;
> +
> +       unsigned product;
> +       unsigned version;
> +
> +       __be16 xfer_buf[16] ____cacheline_aligned;
> +
> +};
>
>   int ad714x_disable(struct ad714x_chip *ad714x);
>   int ad714x_enable(struct ad714x_chip *ad714x);
> --
> 1.7.6
>
>


-- 
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

Re: [PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Dmitry Torokhov]

On Monday, August 22, 2011 04:43:52 AM Michael Hennerich wrote:
> On 08/21/2011 10:09 PM, Dmitry Torokhov wrote:
> > spi_write() requires use of DMA-safe (cacheline aligned) buffers.
> > Also use the same buffers when reading data since to avoid extra
> > locking and potential memory allocation in spi_write_then_read().
> > 
> > Signed-off-by: Dmitry Torokhov<dtor@mail.ru>
> 
> Looks good - one piece of the original patch set got lost.

Aww, sorry about that.

> See below - patch follows.

Thank you very much, I'll fold it in your original patch - no reason
for having a known broken change in the tree if it can be corrected.

-- 
Dmitry

RE: [PATCH 3/4] Input: ad714x - use DMA-safe buffers for spi_write()

[Hennerich, Michael]

Dmitry Torokhov wrote on 2011-08-22:
> On Monday, August 22, 2011 04:43:52 AM Michael Hennerich wrote:
>> On 08/21/2011 10:09 PM, Dmitry Torokhov wrote:
>>> spi_write() requires use of DMA-safe (cacheline aligned) buffers.
>>> Also use the same buffers when reading data since to avoid extra
>>> locking and potential memory allocation in spi_write_then_read().
>>>
>>> Signed-off-by: Dmitry Torokhov<dtor@mail.ru>
>>
>> Looks good - one piece of the original patch set got lost.
>
> Aww, sorry about that.
>
>> See below - patch follows.
>
> Thank you very much, I'll fold it in your original patch - no reason
> for having a known broken change in the tree if it can be corrected.
>

Thanks!

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

[PATCH 4/4] Input: ad714x - read the interrupt status registers in a row

[Dmitry Torokhov]

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

The interrupt status registers should be read in row to avoid invalid data.

Alter "read" method for both bus options to allow reading several registers
in a row and make sure we read interrupt status registers properly.

Read sequence saves 50% of bus transactions compared to single register
reads. So use it also for the result registers, which are also located
in a row.

Also update copyright notice.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---
 drivers/input/misc/ad714x-i2c.c |   11 ++++--
 drivers/input/misc/ad714x-spi.c |   11 ++++--
 drivers/input/misc/ad714x.c     |   62 ++++++++++++++++++++-------------------
 drivers/input/misc/ad714x.h     |    4 +-
 4 files changed, 48 insertions(+), 40 deletions(-)

diff --git a/drivers/input/misc/ad714x-i2c.c b/drivers/input/misc/ad714x-i2c.c
index 6c61218..025417d 100644
--- a/drivers/input/misc/ad714x-i2c.c
+++ b/drivers/input/misc/ad714x-i2c.c
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver (I2C bus)
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -47,9 +47,10 @@ static int ad714x_i2c_write(struct ad714x_chip *chip,
 }
 
 static int ad714x_i2c_read(struct ad714x_chip *chip,
-			   unsigned short reg, unsigned short *data)
+			   unsigned short reg, unsigned short *data, size_t len)
 {
 	struct i2c_client *client = to_i2c_client(chip->dev);
+	int i;
 	int error;
 
 	chip->xfer_buf[0] = cpu_to_be16(reg);
@@ -58,14 +59,16 @@ static int ad714x_i2c_read(struct ad714x_chip *chip,
 				sizeof(*chip->xfer_buf));
 	if (error >= 0)
 		error = i2c_master_recv(client, (u8 *)chip->xfer_buf,
-					sizeof(*chip->xfer_buf));
+					len * sizeof(*chip->xfer_buf));
 
 	if (unlikely(error < 0)) {
 		dev_err(&client->dev, "I2C read error: %d\n", error);
 		return error;
 	}
 
-	*data = be16_to_cpup(chip->xfer_buf);
+	for (i = 0; i < len; i++)
+		data[i] = be16_to_cpu(chip->xfer_buf[i]);
+
 	return 0;
 }
 
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
index 306577d..875b508 100644
--- a/drivers/input/misc/ad714x-spi.c
+++ b/drivers/input/misc/ad714x-spi.c
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver (SPI bus)
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -31,11 +31,12 @@ static int ad714x_spi_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);
 
 static int ad714x_spi_read(struct ad714x_chip *chip,
-			   unsigned short reg, unsigned short *data)
+			   unsigned short reg, unsigned short *data, size_t len)
 {
 	struct spi_device *spi = to_spi_device(chip->dev);
 	struct spi_message message;
 	struct spi_transfer xfer[2];
+	int i;
 	int error;
 
 	spi_message_init(&message);
@@ -48,7 +49,7 @@ static int ad714x_spi_read(struct ad714x_chip *chip,
 	spi_message_add_tail(&xfer[0], &message);
 
 	xfer[1].rx_buf = &chip->xfer_buf[1];
-	xfer[1].len = sizeof(chip->xfer_buf[1]);
+	xfer[1].len = sizeof(chip->xfer_buf[1]) * len;
 	spi_message_add_tail(&xfer[1], &message);
 
 	error = spi_sync(spi, &message);
@@ -57,7 +58,9 @@ static int ad714x_spi_read(struct ad714x_chip *chip,
 		return error;
 	}
 
-	*data = be16_to_cpu(chip->xfer_buf[1]);
+	for (i = 0; i < len; i++)
+		data[i] = be16_to_cpu(chip->xfer_buf[i + 1]);
+
 	return 0;
 }
 
diff --git a/drivers/input/misc/ad714x.c b/drivers/input/misc/ad714x.c
index 2be0366..ca42c7d 100644
--- a/drivers/input/misc/ad714x.c
+++ b/drivers/input/misc/ad714x.c
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -123,6 +123,7 @@ struct ad714x_driver_data {
  * information to integrate all things which will be private data
  * of spi/i2c device
  */
+
 static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 				int start_stage, int end_stage)
 {
@@ -131,11 +132,11 @@ static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 
 	mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 
-	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
 	data |= 1 << end_stage;
 	ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 
-	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
 	data &= ~mask;
 	ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 }
@@ -148,11 +149,11 @@ static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
 
 	mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 
-	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
 	data &= ~(1 << end_stage);
 	ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 
-	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data);
+	ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
 	data |= mask;
 	ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 }
@@ -250,13 +251,16 @@ static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 	struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 	int i;
 
+	ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
+			&ad714x->adc_reg[hw->start_stage],
+			hw->end_stage - hw->start_stage + 1);
+
 	for (i = hw->start_stage; i <= hw->end_stage; i++) {
-		ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
 		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
-				&ad714x->amb_reg[i]);
+				&ad714x->amb_reg[i], 1);
 
-		ad714x->sensor_val[i] = abs(ad714x->adc_reg[i] -
-				ad714x->amb_reg[i]);
+		ad714x->sensor_val[i] =
+			abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
 	}
 }
 
@@ -419,13 +423,16 @@ static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 	struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 	int i;
 
+	ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
+			&ad714x->adc_reg[hw->start_stage],
+			hw->end_stage - hw->start_stage + 1);
+
 	for (i = hw->start_stage; i <= hw->end_stage; i++) {
-		ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
 		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
-				&ad714x->amb_reg[i]);
+				&ad714x->amb_reg[i], 1);
 		if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
-			ad714x->sensor_val[i] = ad714x->adc_reg[i] -
-				ad714x->amb_reg[i];
+			ad714x->sensor_val[i] =
+				ad714x->adc_reg[i] - ad714x->amb_reg[i];
 		else
 			ad714x->sensor_val[i] = 0;
 	}
@@ -570,13 +577,16 @@ static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 	struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 	int i;
 
+	ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
+			&ad714x->adc_reg[hw->x_start_stage],
+			hw->x_end_stage - hw->x_start_stage + 1);
+
 	for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
-		ad714x->read(ad714x, CDC_RESULT_S0 + i, &ad714x->adc_reg[i]);
 		ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
-				&ad714x->amb_reg[i]);
+				&ad714x->amb_reg[i], 1);
 		if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
-			ad714x->sensor_val[i] = ad714x->adc_reg[i] -
-				ad714x->amb_reg[i];
+			ad714x->sensor_val[i] =
+				ad714x->adc_reg[i] - ad714x->amb_reg[i];
 		else
 			ad714x->sensor_val[i] = 0;
 	}
@@ -862,7 +872,7 @@ static int ad714x_hw_detect(struct ad714x_chip *ad714x)
 {
 	unsigned short data;
 
-	ad714x->read(ad714x, AD714X_PARTID_REG, &data);
+	ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
 	switch (data & 0xFFF0) {
 	case AD7142_PARTID:
 		ad714x->product = 0x7142;
@@ -919,14 +929,12 @@ static void ad714x_hw_init(struct ad714x_chip *ad714x)
 		ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
 			ad714x->hw->sys_cfg_reg[i]);
 	for (i = 0; i < SYS_CFGREG_NUM; i++)
-		ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data);
+		ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
 
 	ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
 
 	/* clear all interrupts */
-	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
-	ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
-	ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 }
 
 static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
@@ -936,9 +944,7 @@ static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
 
 	mutex_lock(&ad714x->mutex);
 
-	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state);
-	ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &ad714x->h_state);
-	ad714x->read(ad714x, STG_COM_INT_STA_REG, &ad714x->c_state);
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 
 	for (i = 0; i < ad714x->hw->button_num; i++)
 		ad714x_button_state_machine(ad714x, i);
@@ -1225,8 +1231,6 @@ EXPORT_SYMBOL(ad714x_disable);
 
 int ad714x_enable(struct ad714x_chip *ad714x)
 {
-	unsigned short data;
-
 	dev_dbg(ad714x->dev, "%s enter\n", __func__);
 
 	mutex_lock(&ad714x->mutex);
@@ -1240,9 +1244,7 @@ int ad714x_enable(struct ad714x_chip *ad714x)
 	 * otherwise we will get no chance to enter falling-edge irq again
 	 */
 
-	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &data);
-	ad714x->read(ad714x, STG_HIGH_INT_STA_REG, &data);
-	ad714x->read(ad714x, STG_COM_INT_STA_REG, &data);
+	ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 
 	mutex_unlock(&ad714x->mutex);
 
diff --git a/drivers/input/misc/ad714x.h b/drivers/input/misc/ad714x.h
index d12d149..6edc080 100644
--- a/drivers/input/misc/ad714x.h
+++ b/drivers/input/misc/ad714x.h
@@ -1,7 +1,7 @@
 /*
  * AD714X CapTouch Programmable Controller driver (bus interfaces)
  *
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2011 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */
@@ -18,7 +18,7 @@ struct ad714x_platform_data;
 struct ad714x_driver_data;
 struct ad714x_chip;
 
-typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *);
+typedef int (*ad714x_read_t)(struct ad714x_chip *, unsigned short, unsigned short *, size_t);
 typedef int (*ad714x_write_t)(struct ad714x_chip *, unsigned short, unsigned short);
 
 struct ad714x_chip {
-- 
1.7.6