[PATCHv3 0/9] Convert twl4030-madc to IIO API and add DT support

[PATCHv3 0/9] Convert twl4030-madc to IIO API and add DT support

[Sebastian Reichel]

Hi,

This is PATCHv3 for converting twl4030-madc to the IIO API and
adding DT support. The plan is to remove the private twl4030-madc
API once all users have been removed or converted to the IIO API.
The patchset compiles and has been tested on my Nokia N900.

Changes since PATCHv2 [0]:
 * Added Tested-by: Marek Belisko to all patches, which modify
   code used by twl4030-madc-battery driver
 * Update madc->use_second_irq as suggested by Lee Jones
 * Use dev_err instead of dev_dbg for error messages in probe function
 * Add a space between "{" and ".compatible"
 * Decrease indention of closing "}" in twl4030_madc_driver.driver

[0] https://lkml.org/lkml/2014/3/4/815

-- Sebastian

Sebastian Reichel (9):
  mfd: twl4030-madc: Use managed resources
  mfd: twl4030-madc: Add DT support and convert to IIO framework
  mfd: twl4030-madc: Cleanup driver
  mfd: twl-core: Add twl_i2c_read/write_u16
  mfd: twl4030-madc: Use twl_i2c_read/write_u16 for 16 bit registers
  Documentation: DT: Document twl4030-madc binding
  mfd: twl4030-madc: Move driver to drivers/iio/adc
  iio: documentation: Add ABI documentation for *_mean_raw
  iio: inkern: add iio_read_channel_average_raw

 Documentation/ABI/testing/sysfs-bus-iio            |   8 +
 .../devicetree/bindings/iio/adc/twl4030-madc.txt   |  24 ++
 drivers/iio/adc/Kconfig                            |  10 +
 drivers/iio/adc/Makefile                           |   1 +
 drivers/{mfd => iio/adc}/twl4030-madc.c            | 302 +++++++++++++--------
 drivers/iio/inkern.c                               |  18 ++
 drivers/mfd/Kconfig                                |  10 -
 drivers/mfd/Makefile                               |   1 -
 include/linux/i2c/twl.h                            |  12 +
 include/linux/i2c/twl4030-madc.h                   |   2 +-
 include/linux/iio/consumer.h                       |  13 +
 11 files changed, 275 insertions(+), 126 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/twl4030-madc.txt
 rename drivers/{mfd => iio/adc}/twl4030-madc.c (75%)

-- 
1.9.0

[PATCHv3 1/9] mfd: twl4030-madc: Use managed resources

[Sebastian Reichel]

Update twl4030-madc driver to use managed resources.

Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
Acked-by: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Tested-by: Marek Belisko <marek-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
---
 drivers/mfd/twl4030-madc.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
index 4c583e4..5458561 100644
--- a/drivers/mfd/twl4030-madc.c
+++ b/drivers/mfd/twl4030-madc.c
@@ -702,14 +702,14 @@ static int twl4030_madc_probe(struct platform_device *pdev)
 {
 	struct twl4030_madc_data *madc;
 	struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev);
-	int ret;
+	int irq, ret;
 	u8 regval;
 
 	if (!pdata) {
 		dev_err(&pdev->dev, "platform_data not available\n");
 		return -EINVAL;
 	}
-	madc = kzalloc(sizeof(*madc), GFP_KERNEL);
+	madc = devm_kzalloc(&pdev->dev, sizeof(*madc), GFP_KERNEL);
 	if (!madc)
 		return -ENOMEM;
 
@@ -726,7 +726,7 @@ static int twl4030_madc_probe(struct platform_device *pdev)
 	    TWL4030_MADC_ISR1 : TWL4030_MADC_ISR2;
 	ret = twl4030_madc_set_power(madc, 1);
 	if (ret < 0)
-		goto err_power;
+		return ret;
 	ret = twl4030_madc_set_current_generator(madc, 0, 1);
 	if (ret < 0)
 		goto err_current_generator;
@@ -770,7 +770,9 @@ static int twl4030_madc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, madc);
 	mutex_init(&madc->lock);
-	ret = request_threaded_irq(platform_get_irq(pdev, 0), NULL,
+
+	irq = platform_get_irq(pdev, 0);
+	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
 				   twl4030_madc_threaded_irq_handler,
 				   IRQF_TRIGGER_RISING, "twl4030_madc", madc);
 	if (ret) {
@@ -783,9 +785,6 @@ err_i2c:
 	twl4030_madc_set_current_generator(madc, 0, 0);
 err_current_generator:
 	twl4030_madc_set_power(madc, 0);
-err_power:
-	kfree(madc);
-
 	return ret;
 }
 
@@ -793,10 +792,8 @@ static int twl4030_madc_remove(struct platform_device *pdev)
 {
 	struct twl4030_madc_data *madc = platform_get_drvdata(pdev);
 
-	free_irq(platform_get_irq(pdev, 0), madc);
 	twl4030_madc_set_current_generator(madc, 0, 0);
 	twl4030_madc_set_power(madc, 0);
-	kfree(madc);
 
 	return 0;
 }
-- 
1.9.0

[PATCHv3 2/9] mfd: twl4030-madc: Add DT support and convert to IIO framework

[Sebastian Reichel]

This converts twl4030-madc module to use the Industrial IO ADC
framework and adds device tree support.

Signed-off-by: Sebastian Reichel <sre@debian.org>
Tested-by: Marek Belisko <marek@goldelico.com>
---
 drivers/mfd/twl4030-madc.c | 127 +++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 116 insertions(+), 11 deletions(-)

diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
index 5458561..1c5c4db 100644
--- a/drivers/mfd/twl4030-madc.c
+++ b/drivers/mfd/twl4030-madc.c
@@ -47,11 +47,14 @@
 #include <linux/gfp.h>
 #include <linux/err.h>
 
+#include <linux/iio/iio.h>
+
 /*
  * struct twl4030_madc_data - a container for madc info
  * @dev - pointer to device structure for madc
  * @lock - mutex protecting this data structure
  * @requests - Array of request struct corresponding to SW1, SW2 and RT
+ * @use_second_irq - IRQ selection (main or co-processor)
  * @imr - Interrupt mask register of MADC
  * @isr - Interrupt status register of MADC
  */
@@ -59,10 +62,71 @@ struct twl4030_madc_data {
 	struct device *dev;
 	struct mutex lock;	/* mutex protecting this data structure */
 	struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
+	bool use_second_irq;
 	int imr;
 	int isr;
 };
 
+static int twl4030_madc_read(struct iio_dev *iio_dev,
+			     const struct iio_chan_spec *chan,
+			     int *val, int *val2, long mask)
+{
+	struct twl4030_madc_data *madc = iio_priv(iio_dev);
+	struct twl4030_madc_request req;
+	int ret;
+
+	req.method = madc->use_second_irq ? TWL4030_MADC_SW2 : TWL4030_MADC_SW1;
+
+	req.channels = BIT(chan->channel);
+	req.active = false;
+	req.func_cb = NULL;
+	req.type = TWL4030_MADC_WAIT;
+	req.raw = !(mask == IIO_CHAN_INFO_PROCESSED);
+	req.do_avg = (mask == IIO_CHAN_INFO_AVERAGE_RAW);
+
+	ret = twl4030_madc_conversion(&req);
+	if (ret < 0)
+		return ret;
+
+	*val = req.rbuf[chan->channel];
+
+	return IIO_VAL_INT;
+}
+
+static const struct iio_info twl4030_madc_iio_info = {
+	.read_raw = &twl4030_madc_read,
+	.driver_module = THIS_MODULE,
+};
+
+#define TWL4030_ADC_CHANNEL(_channel, _type, _name) {	\
+	.type = _type,					\
+	.channel = _channel,				\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
+			      BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
+			      BIT(IIO_CHAN_INFO_PROCESSED), \
+	.datasheet_name = _name,			\
+	.indexed = 1,					\
+}
+
+static const struct iio_chan_spec twl4030_madc_iio_channels[] = {
+	TWL4030_ADC_CHANNEL(0, IIO_VOLTAGE, "ADCIN0"),
+	TWL4030_ADC_CHANNEL(1, IIO_TEMP, "ADCIN1"),
+	TWL4030_ADC_CHANNEL(2, IIO_VOLTAGE, "ADCIN2"),
+	TWL4030_ADC_CHANNEL(3, IIO_VOLTAGE, "ADCIN3"),
+	TWL4030_ADC_CHANNEL(4, IIO_VOLTAGE, "ADCIN4"),
+	TWL4030_ADC_CHANNEL(5, IIO_VOLTAGE, "ADCIN5"),
+	TWL4030_ADC_CHANNEL(6, IIO_VOLTAGE, "ADCIN6"),
+	TWL4030_ADC_CHANNEL(7, IIO_VOLTAGE, "ADCIN7"),
+	TWL4030_ADC_CHANNEL(8, IIO_VOLTAGE, "ADCIN8"),
+	TWL4030_ADC_CHANNEL(9, IIO_VOLTAGE, "ADCIN9"),
+	TWL4030_ADC_CHANNEL(10, IIO_CURRENT, "ADCIN10"),
+	TWL4030_ADC_CHANNEL(11, IIO_VOLTAGE, "ADCIN11"),
+	TWL4030_ADC_CHANNEL(12, IIO_VOLTAGE, "ADCIN12"),
+	TWL4030_ADC_CHANNEL(13, IIO_VOLTAGE, "ADCIN13"),
+	TWL4030_ADC_CHANNEL(14, IIO_VOLTAGE, "ADCIN14"),
+	TWL4030_ADC_CHANNEL(15, IIO_VOLTAGE, "ADCIN15"),
+};
+
 static struct twl4030_madc_data *twl4030_madc;
 
 struct twl4030_prescale_divider_ratios {
@@ -702,28 +766,49 @@ static int twl4030_madc_probe(struct platform_device *pdev)
 {
 	struct twl4030_madc_data *madc;
 	struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct device_node *np = pdev->dev.of_node;
 	int irq, ret;
 	u8 regval;
+	struct iio_dev *iio_dev = NULL;
 
-	if (!pdata) {
-		dev_err(&pdev->dev, "platform_data not available\n");
+	if (!pdata && !np) {
+		dev_err(&pdev->dev, "neither platform data nor Device Tree node available\n");
 		return -EINVAL;
 	}
-	madc = devm_kzalloc(&pdev->dev, sizeof(*madc), GFP_KERNEL);
-	if (!madc)
+
+	iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*madc));
+	if (!iio_dev) {
+		dev_err(&pdev->dev, "failed allocating iio device\n");
 		return -ENOMEM;
+	}
 
+	madc = iio_priv(iio_dev);
 	madc->dev = &pdev->dev;
 
+	iio_dev->name = dev_name(&pdev->dev);
+	iio_dev->dev.parent = &pdev->dev;
+	iio_dev->dev.of_node = pdev->dev.of_node;
+	iio_dev->info = &twl4030_madc_iio_info;
+	iio_dev->modes = INDIO_DIRECT_MODE;
+	iio_dev->channels = twl4030_madc_iio_channels;
+	iio_dev->num_channels = ARRAY_SIZE(twl4030_madc_iio_channels);
+
 	/*
 	 * Phoenix provides 2 interrupt lines. The first one is connected to
 	 * the OMAP. The other one can be connected to the other processor such
 	 * as modem. Hence two separate ISR and IMR registers.
 	 */
-	madc->imr = (pdata->irq_line == 1) ?
-	    TWL4030_MADC_IMR1 : TWL4030_MADC_IMR2;
-	madc->isr = (pdata->irq_line == 1) ?
-	    TWL4030_MADC_ISR1 : TWL4030_MADC_ISR2;
+	if (pdata)
+		madc->use_second_irq = (pdata->irq_line != 1);
+	else
+		madc->use_second_irq = of_property_read_bool(np,
+				       "ti,system-uses-second-madc-irq");
+
+	madc->imr = madc->use_second_irq ? TWL4030_MADC_IMR2 :
+					   TWL4030_MADC_IMR1;
+	madc->isr = madc->use_second_irq ? TWL4030_MADC_ISR2 :
+					   TWL4030_MADC_ISR1;
+
 	ret = twl4030_madc_set_power(madc, 1);
 	if (ret < 0)
 		return ret;
@@ -768,7 +853,7 @@ static int twl4030_madc_probe(struct platform_device *pdev)
 		}
 	}
 
-	platform_set_drvdata(pdev, madc);
+	platform_set_drvdata(pdev, iio_dev);
 	mutex_init(&madc->lock);
 
 	irq = platform_get_irq(pdev, 0);
@@ -776,11 +861,19 @@ static int twl4030_madc_probe(struct platform_device *pdev)
 				   twl4030_madc_threaded_irq_handler,
 				   IRQF_TRIGGER_RISING, "twl4030_madc", madc);
 	if (ret) {
-		dev_dbg(&pdev->dev, "could not request irq\n");
+		dev_err(&pdev->dev, "could not request irq\n");
 		goto err_i2c;
 	}
 	twl4030_madc = madc;
+
+	ret = iio_device_register(iio_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "could not register iio device\n");
+		goto err_i2c;
+	}
+
 	return 0;
+
 err_i2c:
 	twl4030_madc_set_current_generator(madc, 0, 0);
 err_current_generator:
@@ -790,20 +883,32 @@ err_current_generator:
 
 static int twl4030_madc_remove(struct platform_device *pdev)
 {
-	struct twl4030_madc_data *madc = platform_get_drvdata(pdev);
+	struct iio_dev *iio_dev = platform_get_drvdata(pdev);
+	struct twl4030_madc_data *madc = iio_priv(iio_dev);
 
 	twl4030_madc_set_current_generator(madc, 0, 0);
 	twl4030_madc_set_power(madc, 0);
 
+	iio_device_unregister(iio_dev);
+
 	return 0;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id twl_madc_of_match[] = {
+	{ .compatible = "ti,twl4030-madc", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, twl_madc_of_match);
+#endif
+
 static struct platform_driver twl4030_madc_driver = {
 	.probe = twl4030_madc_probe,
 	.remove = twl4030_madc_remove,
 	.driver = {
 		   .name = "twl4030_madc",
 		   .owner = THIS_MODULE,
+		   .of_match_table = of_match_ptr(twl_madc_of_match),
 		   },
 };
 
-- 
1.9.0

[PATCHv3 3/9] mfd: twl4030-madc: Cleanup driver

[Sebastian Reichel]

Some style fixes in twl4030-madc driver.

Reported-by: Jonathan Cameron <jic23@kernel.org>
Reported-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sebastian Reichel <sre@debian.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Marek Belisko <marek@goldelico.com>
---
 drivers/mfd/twl4030-madc.c       | 127 +++++++++++++++++++--------------------
 include/linux/i2c/twl4030-madc.h |   2 +-
 2 files changed, 62 insertions(+), 67 deletions(-)

diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
index 1c5c4db..890d520 100644
--- a/drivers/mfd/twl4030-madc.c
+++ b/drivers/mfd/twl4030-madc.c
@@ -49,22 +49,22 @@
 
 #include <linux/iio/iio.h>
 
-/*
+/**
  * struct twl4030_madc_data - a container for madc info
- * @dev - pointer to device structure for madc
- * @lock - mutex protecting this data structure
- * @requests - Array of request struct corresponding to SW1, SW2 and RT
- * @use_second_irq - IRQ selection (main or co-processor)
- * @imr - Interrupt mask register of MADC
- * @isr - Interrupt status register of MADC
+ * @dev:		Pointer to device structure for madc
+ * @lock:		Mutex protecting this data structure
+ * @requests:		Array of request struct corresponding to SW1, SW2 and RT
+ * @use_second_irq:	IRQ selection (main or co-processor)
+ * @imr:		Interrupt mask register of MADC
+ * @isr:		Interrupt status register of MADC
  */
 struct twl4030_madc_data {
 	struct device *dev;
 	struct mutex lock;	/* mutex protecting this data structure */
 	struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
 	bool use_second_irq;
-	int imr;
-	int isr;
+	u8 imr;
+	u8 isr;
 };
 
 static int twl4030_madc_read(struct iio_dev *iio_dev,
@@ -155,17 +155,16 @@ twl4030_divider_ratios[16] = {
 };
 
 
-/*
- * Conversion table from -3 to 55 degree Celcius
- */
-static int therm_tbl[] = {
-30800,	29500,	28300,	27100,
-26000,	24900,	23900,	22900,	22000,	21100,	20300,	19400,	18700,	17900,
-17200,	16500,	15900,	15300,	14700,	14100,	13600,	13100,	12600,	12100,
-11600,	11200,	10800,	10400,	10000,	9630,	9280,	8950,	8620,	8310,
-8020,	7730,	7460,	7200,	6950,	6710,	6470,	6250,	6040,	5830,
-5640,	5450,	5260,	5090,	4920,	4760,	4600,	4450,	4310,	4170,
-4040,	3910,	3790,	3670,	3550
+/* Conversion table from -3 to 55 degrees Celcius */
+static int twl4030_therm_tbl[] = {
+	30800,	29500,	28300,	27100,
+	26000,	24900,	23900,	22900,	22000,	21100,	20300,	19400,	18700,
+	17900,	17200,	16500,	15900,	15300,	14700,	14100,	13600,	13100,
+	12600,	12100,	11600,	11200,	10800,	10400,	10000,	9630,	9280,
+	8950,	8620,	8310,	8020,	7730,	7460,	7200,	6950,	6710,
+	6470,	6250,	6040,	5830,	5640,	5450,	5260,	5090,	4920,
+	4760,	4600,	4450,	4310,	4170,	4040,	3910,	3790,	3670,
+	3550
 };
 
 /*
@@ -197,11 +196,12 @@ const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = {
 			      },
 };
 
-/*
- * Function to read a particular channel value.
- * @madc - pointer to struct twl4030_madc_data
- * @reg - lsb of ADC Channel
- * If the i2c read fails it returns an error else returns 0.
+/**
+ * twl4030_madc_channel_raw_read() - Function to read a particular channel value
+ * @madc:	pointer to struct twl4030_madc_data
+ * @reg:	lsb of ADC Channel
+ *
+ * Return: 0 on success, an error code otherwise.
  */
 static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
 {
@@ -227,7 +227,7 @@ static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
 }
 
 /*
- * Return battery temperature
+ * Return battery temperature in degrees Celsius
  * Or < 0 on failure.
  */
 static int twl4030battery_temperature(int raw_volt)
@@ -236,18 +236,18 @@ static int twl4030battery_temperature(int raw_volt)
 	int temp, curr, volt, res, ret;
 
 	volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R;
-	/* Getting and calculating the supply current in micro ampers */
+	/* Getting and calculating the supply current in micro amperes */
 	ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val,
 		REG_BCICTL2);
 	if (ret < 0)
 		return ret;
+
 	curr = ((val & TWL4030_BCI_ITHEN) + 1) * 10;
 	/* Getting and calculating the thermistor resistance in ohms */
 	res = volt * 1000 / curr;
 	/* calculating temperature */
 	for (temp = 58; temp >= 0; temp--) {
-		int actual = therm_tbl[temp];
-
+		int actual = twl4030_therm_tbl[temp];
 		if ((actual - res) >= 0)
 			break;
 	}
@@ -269,11 +269,12 @@ static int twl4030battery_current(int raw_volt)
 	else /* slope of 0.88 mV/mA */
 		return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2;
 }
+
 /*
  * Function to read channel values
  * @madc - pointer to twl4030_madc_data struct
  * @reg_base - Base address of the first channel
- * @Channels - 16 bit bitmap. If the bit is set, channel value is read
+ * @Channels - 16 bit bitmap. If the bit is set, channel's value is read
  * @buf - The channel values are stored here. if read fails error
  * @raw - Return raw values without conversion
  * value is stored
@@ -284,17 +285,17 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
 				      long channels, int *buf,
 				      bool raw)
 {
-	int count = 0, count_req = 0, i;
+	int count = 0;
+	int i;
 	u8 reg;
 
 	for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) {
-		reg = reg_base + 2 * i;
+		reg = reg_base + (2 * i);
 		buf[i] = twl4030_madc_channel_raw_read(madc, reg);
 		if (buf[i] < 0) {
-			dev_err(madc->dev,
-				"Unable to read register 0x%X\n", reg);
-			count_req++;
-			continue;
+			dev_err(madc->dev, "Unable to read register 0x%X\n",
+				reg);
+			return buf[i];
 		}
 		if (raw) {
 			count++;
@@ -305,7 +306,7 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
 			buf[i] = twl4030battery_current(buf[i]);
 			if (buf[i] < 0) {
 				dev_err(madc->dev, "err reading current\n");
-				count_req++;
+				return buf[i];
 			} else {
 				count++;
 				buf[i] = buf[i] - 750;
@@ -315,7 +316,7 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
 			buf[i] = twl4030battery_temperature(buf[i]);
 			if (buf[i] < 0) {
 				dev_err(madc->dev, "err reading temperature\n");
-				count_req++;
+				return buf[i];
 			} else {
 				buf[i] -= 3;
 				count++;
@@ -336,8 +337,6 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
 				twl4030_divider_ratios[i].numerator);
 		}
 	}
-	if (count_req)
-		dev_err(madc->dev, "%d channel conversion failed\n", count_req);
 
 	return count;
 }
@@ -361,13 +360,13 @@ static int twl4030_madc_enable_irq(struct twl4030_madc_data *madc, u8 id)
 			madc->imr);
 		return ret;
 	}
+
 	val &= ~(1 << id);
 	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
 	if (ret) {
 		dev_err(madc->dev,
 			"unable to write imr register 0x%X\n", madc->imr);
 		return ret;
-
 	}
 
 	return 0;
@@ -430,7 +429,7 @@ static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc)
 			continue;
 		ret = twl4030_madc_disable_irq(madc, i);
 		if (ret < 0)
-			dev_dbg(madc->dev, "Disable interrupt failed%d\n", i);
+			dev_dbg(madc->dev, "Disable interrupt failed %d\n", i);
 		madc->requests[i].result_pending = 1;
 	}
 	for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
@@ -512,21 +511,17 @@ static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc,
 {
 	const struct twl4030_madc_conversion_method *method;
 	int ret = 0;
+
+	if (conv_method != TWL4030_MADC_SW1 && conv_method != TWL4030_MADC_SW2)
+		return -ENOTSUPP;
+
 	method = &twl4030_conversion_methods[conv_method];
-	switch (conv_method) {
-	case TWL4030_MADC_SW1:
-	case TWL4030_MADC_SW2:
-		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
-				       TWL4030_MADC_SW_START, method->ctrl);
-		if (ret) {
-			dev_err(madc->dev,
-				"unable to write ctrl register 0x%X\n",
-				method->ctrl);
-			return ret;
-		}
-		break;
-	default:
-		break;
+	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, TWL4030_MADC_SW_START,
+			       method->ctrl);
+	if (ret) {
+		dev_err(madc->dev, "unable to write ctrl register 0x%X\n",
+			method->ctrl);
+		return ret;
 	}
 
 	return 0;
@@ -623,8 +618,8 @@ int twl4030_madc_conversion(struct twl4030_madc_request *req)
 				       ch_lsb, method->avg);
 		if (ret) {
 			dev_err(twl4030_madc->dev,
-				"unable to write sel reg 0x%X\n",
-				method->sel + 1);
+				"unable to write avg reg 0x%X\n",
+				method->avg);
 			goto out;
 		}
 	}
@@ -665,10 +660,6 @@ out:
 }
 EXPORT_SYMBOL_GPL(twl4030_madc_conversion);
 
-/*
- * Return channel value
- * Or < 0 on failure.
- */
 int twl4030_get_madc_conversion(int channel_no)
 {
 	struct twl4030_madc_request req;
@@ -703,6 +694,7 @@ static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
 					      int chan, int on)
 {
 	int ret;
+	int regmask;
 	u8 regval;
 
 	ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE,
@@ -712,10 +704,13 @@ static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
 			TWL4030_BCI_BCICTL1);
 		return ret;
 	}
+
+	regmask = chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
 	if (on)
-		regval |= chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
+		regval |= regmask;
 	else
-		regval &= chan ? ~TWL4030_BCI_ITHEN : ~TWL4030_BCI_TYPEN;
+		regval &= ~regmask;
+
 	ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
 			       regval, TWL4030_BCI_BCICTL1);
 	if (ret) {
@@ -730,7 +725,7 @@ static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
 /*
  * Function that sets MADC software power on bit to enable MADC
  * @madc - pointer to twl4030_madc_data struct
- * @on - Enable or disable MADC software powen on bit.
+ * @on - Enable or disable MADC software power on bit.
  * returns error if i2c read/write fails else 0
  */
 static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on)
@@ -909,7 +904,7 @@ static struct platform_driver twl4030_madc_driver = {
 		   .name = "twl4030_madc",
 		   .owner = THIS_MODULE,
 		   .of_match_table = of_match_ptr(twl_madc_of_match),
-		   },
+	},
 };
 
 module_platform_driver(twl4030_madc_driver);
diff --git a/include/linux/i2c/twl4030-madc.h b/include/linux/i2c/twl4030-madc.h
index 01f5951..1c0134d 100644
--- a/include/linux/i2c/twl4030-madc.h
+++ b/include/linux/i2c/twl4030-madc.h
@@ -44,7 +44,7 @@ struct twl4030_madc_conversion_method {
 
 struct twl4030_madc_request {
 	unsigned long channels;
-	u16 do_avg;
+	bool do_avg;
 	u16 method;
 	u16 type;
 	bool active;
-- 
1.9.0

[PATCHv3 4/9] mfd: twl-core: Add twl_i2c_read/write_u16

[Sebastian Reichel]

Add a simple twl_i2c_read/write_u16 wrapper over
the twl_i2c_read/write, which is similar to the
twl_i2c_read/write_u8 wrapper.

Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
Acked-by: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Tested-by: Marek Belisko <marek-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
---
 include/linux/i2c/twl.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/i2c/twl.h b/include/linux/i2c/twl.h
index ade1c06..d2b1670 100644
--- a/include/linux/i2c/twl.h
+++ b/include/linux/i2c/twl.h
@@ -195,6 +195,18 @@ static inline int twl_i2c_read_u8(u8 mod_no, u8 *val, u8 reg) {
 	return twl_i2c_read(mod_no, val, reg, 1);
 }
 
+static inline int twl_i2c_write_u16(u8 mod_no, u16 val, u8 reg) {
+	val = cpu_to_le16(val);
+	return twl_i2c_write(mod_no, (u8*) &val, reg, 2);
+}
+
+static inline int twl_i2c_read_u16(u8 mod_no, u16 *val, u8 reg) {
+	int ret;
+	ret = twl_i2c_read(mod_no, (u8*) val, reg, 2);
+	*val = le16_to_cpu(*val);
+	return ret;
+}
+
 int twl_get_type(void);
 int twl_get_version(void);
 int twl_get_hfclk_rate(void);
-- 
1.9.0

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[PATCHv3 5/9] mfd: twl4030-madc: Use twl_i2c_read/write_u16 for 16 bit registers

[Sebastian Reichel]

Simplify reading and writing of 16 bit TWL registers in the
driver by using twl_i2c_read_u16 and twl_i2c_write_u16.

Signed-off-by: Sebastian Reichel <sre@debian.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Tested-by: Marek Belisko <marek@goldelico.com>
---
 drivers/mfd/twl4030-madc.c | 39 ++++++++-------------------------------
 1 file changed, 8 insertions(+), 31 deletions(-)

diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
index 890d520..ccfb10d 100644
--- a/drivers/mfd/twl4030-madc.c
+++ b/drivers/mfd/twl4030-madc.c
@@ -205,25 +205,19 @@ const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = {
  */
 static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
 {
-	u8 msb, lsb;
+	u16 val;
 	int ret;
 	/*
 	 * For each ADC channel, we have MSB and LSB register pair. MSB address
 	 * is always LSB address+1. reg parameter is the address of LSB register
 	 */
-	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &msb, reg + 1);
+	ret = twl_i2c_read_u16(TWL4030_MODULE_MADC, &val, reg);
 	if (ret) {
-		dev_err(madc->dev, "unable to read MSB register 0x%X\n",
-			reg + 1);
-		return ret;
-	}
-	ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &lsb, reg);
-	if (ret) {
-		dev_err(madc->dev, "unable to read LSB register 0x%X\n", reg);
+		dev_err(madc->dev, "unable to read register 0x%X\n", reg);
 		return ret;
 	}
 
-	return (int)(((msb << 8) | lsb) >> 6);
+	return (int)(val >> 6);
 }
 
 /*
@@ -572,7 +566,6 @@ static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc,
 int twl4030_madc_conversion(struct twl4030_madc_request *req)
 {
 	const struct twl4030_madc_conversion_method *method;
-	u8 ch_msb, ch_lsb;
 	int ret;
 
 	if (!req || !twl4030_madc)
@@ -588,37 +581,21 @@ int twl4030_madc_conversion(struct twl4030_madc_request *req)
 		ret = -EBUSY;
 		goto out;
 	}
-	ch_msb = (req->channels >> 8) & 0xff;
-	ch_lsb = req->channels & 0xff;
 	method = &twl4030_conversion_methods[req->method];
 	/* Select channels to be converted */
-	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, ch_msb, method->sel + 1);
+	ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, method->sel);
 	if (ret) {
 		dev_err(twl4030_madc->dev,
-			"unable to write sel register 0x%X\n", method->sel + 1);
-		goto out;
-	}
-	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, ch_lsb, method->sel);
-	if (ret) {
-		dev_err(twl4030_madc->dev,
-			"unable to write sel register 0x%X\n", method->sel + 1);
+			"unable to write sel register 0x%X\n", method->sel);
 		goto out;
 	}
 	/* Select averaging for all channels if do_avg is set */
 	if (req->do_avg) {
-		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
-				       ch_msb, method->avg + 1);
+		ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels,
+				       method->avg);
 		if (ret) {
 			dev_err(twl4030_madc->dev,
 				"unable to write avg register 0x%X\n",
-				method->avg + 1);
-			goto out;
-		}
-		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
-				       ch_lsb, method->avg);
-		if (ret) {
-			dev_err(twl4030_madc->dev,
-				"unable to write avg reg 0x%X\n",
 				method->avg);
 			goto out;
 		}
-- 
1.9.0

[PATCHv3 6/9] Documentation: DT: Document twl4030-madc binding

[Sebastian Reichel]

Add devicetree binding documentation for twl4030-madc
analog digital converter.

Signed-off-by: Sebastian Reichel <sre@debian.org>
---
 .../devicetree/bindings/iio/adc/twl4030-madc.txt   | 24 ++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/twl4030-madc.txt

diff --git a/Documentation/devicetree/bindings/iio/adc/twl4030-madc.txt b/Documentation/devicetree/bindings/iio/adc/twl4030-madc.txt
new file mode 100644
index 0000000..6bdd214
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/twl4030-madc.txt
@@ -0,0 +1,24 @@
+* TWL4030 Monitoring Analog to Digital Converter (MADC)
+
+The MADC subsystem in the TWL4030 consists of a 10-bit ADC
+combined with a 16-input analog multiplexer.
+
+Required properties:
+  - compatible: Should contain "ti,twl4030-madc".
+  - interrupts: IRQ line for the MADC submodule.
+  - #io-channel-cells: Should be set to <1>.
+
+Optional properties:
+  - ti,system-uses-second-madc-irq: boolean, set if the second madc irq register
+				    should be used, which is intended to be used
+				    by Co-Processors (e.g. a modem).
+
+Example:
+
+&twl {
+	madc {
+		compatible = "ti,twl4030-madc";
+		interrupts = <3>;
+		#io-channel-cells = <1>;
+	};
+};
-- 
1.9.0

[PATCHv3 7/9] mfd: twl4030-madc: Move driver to drivers/iio/adc

[Sebastian Reichel]

This is a driver for an A/D converter, which belongs into
drivers/iio/adc.

Signed-off-by: Sebastian Reichel <sre@debian.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/adc/Kconfig                 | 10 ++++++++++
 drivers/iio/adc/Makefile                |  1 +
 drivers/{mfd => iio/adc}/twl4030-madc.c |  0
 drivers/mfd/Kconfig                     | 10 ----------
 drivers/mfd/Makefile                    |  1 -
 5 files changed, 11 insertions(+), 11 deletions(-)
 rename drivers/{mfd => iio/adc}/twl4030-madc.c (100%)

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 2209f28..427f75c 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -183,6 +183,16 @@ config TI_AM335X_ADC
 	  Say yes here to build support for Texas Instruments ADC
 	  driver which is also a MFD client.
 
+config TWL4030_MADC
+	tristate "TWL4030 MADC (Monitoring A/D Converter)"
+	depends on TWL4030_CORE
+	help
+	This driver provides support for Triton TWL4030-MADC. The
+	driver supports both RT and SW conversion methods.
+
+	This driver can also be built as a module. If so, the module will be
+	called twl4030-madc.
+
 config TWL6030_GPADC
 	tristate "TWL6030 GPADC (General Purpose A/D Converter) Support"
 	depends on TWL4030_CORE
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index ba9a10a..9acf2df 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -20,5 +20,6 @@ obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_NAU7802) += nau7802.o
 obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
 obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
+obj-$(CONFIG_TWL4030_MADC) += twl4030-madc.o
 obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o
 obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
diff --git a/drivers/mfd/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c
similarity index 100%
rename from drivers/mfd/twl4030-madc.c
rename to drivers/iio/adc/twl4030-madc.c
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 49bb445..23a8a51 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -935,16 +935,6 @@ config TWL4030_CORE
 	  high speed USB OTG transceiver, an audio codec (on most
 	  versions) and many other features.
 
-config TWL4030_MADC
-	tristate "TI TWL4030 MADC"
-	depends on TWL4030_CORE
-	help
-	This driver provides support for triton TWL4030-MADC. The
-	driver supports both RT and SW conversion methods.
-
-	This driver can be built as a module. If so it will be
-	named twl4030-madc
-
 config TWL4030_POWER
 	bool "TI TWL4030 power resources"
 	depends on TWL4030_CORE && ARM
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 5aea5ef..c8eb0bc 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -71,7 +71,6 @@ obj-$(CONFIG_MFD_TPS80031)	+= tps80031.o
 obj-$(CONFIG_MENELAUS)		+= menelaus.o
 
 obj-$(CONFIG_TWL4030_CORE)	+= twl-core.o twl4030-irq.o twl6030-irq.o
-obj-$(CONFIG_TWL4030_MADC)      += twl4030-madc.o
 obj-$(CONFIG_TWL4030_POWER)    += twl4030-power.o
 obj-$(CONFIG_MFD_TWL4030_AUDIO)	+= twl4030-audio.o
 obj-$(CONFIG_TWL6040_CORE)	+= twl6040.o
-- 
1.9.0

[PATCHv3 8/9] iio: documentation: Add ABI documentation for *_mean_raw

[Sebastian Reichel]

Add ABI documentation for in_*_mean_raw files, which are
already supported and used in the kernel for some time.

Signed-off-by: Sebastian Reichel <sre@debian.org>
---
 Documentation/ABI/testing/sysfs-bus-iio | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index 6e02c50..58ba333 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -210,6 +210,14 @@ Contact:	linux-iio@vger.kernel.org
 Description:
 		Scaled humidity measurement in milli percent.
 
+What:		/sys/bus/iio/devices/iio:deviceX/in_X_mean_raw
+KernelVersion:	3.5
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Averaged raw measurement from channel X. The number of values
+		used for averaging is device specific. The converting rules for
+		normal raw values also applies to the averaged raw values.
+
 What:		/sys/bus/iio/devices/iio:deviceX/in_accel_offset
 What:		/sys/bus/iio/devices/iio:deviceX/in_accel_x_offset
 What:		/sys/bus/iio/devices/iio:deviceX/in_accel_y_offset
-- 
1.9.0

[PATCHv3 9/9] iio: inkern: add iio_read_channel_average_raw

[Sebastian Reichel]

Add iio_read_channel_average_raw to support reading
averaged raw values in consumer drivers.

Signed-off-by: Sebastian Reichel <sre@debian.org>
---
 drivers/iio/inkern.c         | 18 ++++++++++++++++++
 include/linux/iio/consumer.h | 13 +++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index 0cf5f8e..adeba5a 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -443,6 +443,24 @@ err_unlock:
 }
 EXPORT_SYMBOL_GPL(iio_read_channel_raw);
 
+int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
+{
+	int ret;
+
+	mutex_lock(&chan->indio_dev->info_exist_lock);
+	if (chan->indio_dev->info == NULL) {
+		ret = -ENODEV;
+		goto err_unlock;
+	}
+
+	ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_AVERAGE_RAW);
+err_unlock:
+	mutex_unlock(&chan->indio_dev->info_exist_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_average_raw);
+
 static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
 	int raw, int *processed, unsigned int scale)
 {
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index 2752b1f..651f9a0 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -123,6 +123,19 @@ int iio_read_channel_raw(struct iio_channel *chan,
 			 int *val);
 
 /**
+ * iio_read_channel_average_raw() - read from a given channel
+ * @chan:		The channel being queried.
+ * @val:		Value read back.
+ *
+ * Note raw reads from iio channels are in adc counts and hence
+ * scale will need to be applied if standard units required.
+ *
+ * In opposit to the normal iio_read_channel_raw this function
+ * returns the average of multiple reads.
+ */
+int iio_read_channel_average_raw(struct iio_channel *chan, int *val);
+
+/**
  * iio_read_channel_processed() - read processed value from a given channel
  * @chan:		The channel being queried.
  * @val:		Value read back.
-- 
1.9.0

Re: [PATCHv3 2/9] mfd: twl4030-madc: Add DT support and convert to IIO framework

[Lee Jones]

> This converts twl4030-madc module to use the Industrial IO ADC
> framework and adds device tree support.
> 
> Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
> Tested-by: Marek Belisko <marek-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
> ---
>  drivers/mfd/twl4030-madc.c | 127 +++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 116 insertions(+), 11 deletions(-)

It looks as if my previous review comments have been addressed.
  Acked-by: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCHv3 1/9] mfd: twl4030-madc: Use managed resources

[Jonathan Cameron]

On 10/03/14 17:25, Sebastian Reichel wrote:
> Update twl4030-madc driver to use managed resources.
>
> Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
> Acked-by: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Tested-by: Marek Belisko <marek-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
My email client was having a crazy day and not showing me this revision of the
patches - I'll bring my comments across so they don't get lost.

Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>


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Re: [PATCHv3 2/9] mfd: twl4030-madc: Add DT support and convert to IIO framework

[Jonathan Cameron]

On 10/03/14 17:25, Sebastian Reichel wrote:
> This converts twl4030-madc module to use the Industrial IO ADC
> framework and adds device tree support.
>
> Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
> Tested-by: Marek Belisko <marek-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>

One issue in the remove function.  Reorder that
and I'm happy.

> ---
>   drivers/mfd/twl4030-madc.c | 127 +++++++++++++++++++++++++++++++++++++++++----
>   1 file changed, 116 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
> index 5458561..1c5c4db 100644
> --- a/drivers/mfd/twl4030-madc.c
> +++ b/drivers/mfd/twl4030-madc.c
> @@ -47,11 +47,14 @@
>   #include <linux/gfp.h>
>   #include <linux/err.h>
>
> +#include <linux/iio/iio.h>
> +
>   /*
>    * struct twl4030_madc_data - a container for madc info
>    * @dev - pointer to device structure for madc
>    * @lock - mutex protecting this data structure
>    * @requests - Array of request struct corresponding to SW1, SW2 and RT
> + * @use_second_irq - IRQ selection (main or co-processor)
>    * @imr - Interrupt mask register of MADC
>    * @isr - Interrupt status register of MADC
>    */
> @@ -59,10 +62,71 @@ struct twl4030_madc_data {
>   	struct device *dev;
>   	struct mutex lock;	/* mutex protecting this data structure */
>   	struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
> +	bool use_second_irq;
>   	int imr;
>   	int isr;
>   };
>
> +static int twl4030_madc_read(struct iio_dev *iio_dev,
> +			     const struct iio_chan_spec *chan,
> +			     int *val, int *val2, long mask)
> +{
> +	struct twl4030_madc_data *madc = iio_priv(iio_dev);
> +	struct twl4030_madc_request req;
> +	int ret;
> +
> +	req.method = madc->use_second_irq ? TWL4030_MADC_SW2 : TWL4030_MADC_SW1;
> +
> +	req.channels = BIT(chan->channel);
> +	req.active = false;
> +	req.func_cb = NULL;
> +	req.type = TWL4030_MADC_WAIT;
> +	req.raw = !(mask == IIO_CHAN_INFO_PROCESSED);
> +	req.do_avg = (mask == IIO_CHAN_INFO_AVERAGE_RAW);
> +
> +	ret = twl4030_madc_conversion(&req);
> +	if (ret < 0)
> +		return ret;
> +
> +	*val = req.rbuf[chan->channel];
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static const struct iio_info twl4030_madc_iio_info = {
> +	.read_raw = &twl4030_madc_read,
> +	.driver_module = THIS_MODULE,
> +};
> +
> +#define TWL4030_ADC_CHANNEL(_channel, _type, _name) {	\
> +	.type = _type,					\
> +	.channel = _channel,				\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
> +			      BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
> +			      BIT(IIO_CHAN_INFO_PROCESSED), \
> +	.datasheet_name = _name,			\
> +	.indexed = 1,					\
> +}
> +
> +static const struct iio_chan_spec twl4030_madc_iio_channels[] = {
> +	TWL4030_ADC_CHANNEL(0, IIO_VOLTAGE, "ADCIN0"),
> +	TWL4030_ADC_CHANNEL(1, IIO_TEMP, "ADCIN1"),
> +	TWL4030_ADC_CHANNEL(2, IIO_VOLTAGE, "ADCIN2"),
> +	TWL4030_ADC_CHANNEL(3, IIO_VOLTAGE, "ADCIN3"),
> +	TWL4030_ADC_CHANNEL(4, IIO_VOLTAGE, "ADCIN4"),
> +	TWL4030_ADC_CHANNEL(5, IIO_VOLTAGE, "ADCIN5"),
> +	TWL4030_ADC_CHANNEL(6, IIO_VOLTAGE, "ADCIN6"),
> +	TWL4030_ADC_CHANNEL(7, IIO_VOLTAGE, "ADCIN7"),
> +	TWL4030_ADC_CHANNEL(8, IIO_VOLTAGE, "ADCIN8"),
> +	TWL4030_ADC_CHANNEL(9, IIO_VOLTAGE, "ADCIN9"),
> +	TWL4030_ADC_CHANNEL(10, IIO_CURRENT, "ADCIN10"),
> +	TWL4030_ADC_CHANNEL(11, IIO_VOLTAGE, "ADCIN11"),
> +	TWL4030_ADC_CHANNEL(12, IIO_VOLTAGE, "ADCIN12"),
> +	TWL4030_ADC_CHANNEL(13, IIO_VOLTAGE, "ADCIN13"),
> +	TWL4030_ADC_CHANNEL(14, IIO_VOLTAGE, "ADCIN14"),
> +	TWL4030_ADC_CHANNEL(15, IIO_VOLTAGE, "ADCIN15"),
> +};
> +
>   static struct twl4030_madc_data *twl4030_madc;
>
>   struct twl4030_prescale_divider_ratios {
> @@ -702,28 +766,49 @@ static int twl4030_madc_probe(struct platform_device *pdev)
>   {
>   	struct twl4030_madc_data *madc;
>   	struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev);
> +	struct device_node *np = pdev->dev.of_node;
>   	int irq, ret;
>   	u8 regval;
> +	struct iio_dev *iio_dev = NULL;
>
> -	if (!pdata) {
> -		dev_err(&pdev->dev, "platform_data not available\n");
> +	if (!pdata && !np) {
> +		dev_err(&pdev->dev, "neither platform data nor Device Tree node available\n");
>   		return -EINVAL;
>   	}
> -	madc = devm_kzalloc(&pdev->dev, sizeof(*madc), GFP_KERNEL);
> -	if (!madc)
> +
> +	iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*madc));
> +	if (!iio_dev) {
> +		dev_err(&pdev->dev, "failed allocating iio device\n");
>   		return -ENOMEM;
> +	}
>
> +	madc = iio_priv(iio_dev);
>   	madc->dev = &pdev->dev;
>
> +	iio_dev->name = dev_name(&pdev->dev);
> +	iio_dev->dev.parent = &pdev->dev;
> +	iio_dev->dev.of_node = pdev->dev.of_node;
> +	iio_dev->info = &twl4030_madc_iio_info;
> +	iio_dev->modes = INDIO_DIRECT_MODE;
> +	iio_dev->channels = twl4030_madc_iio_channels;
> +	iio_dev->num_channels = ARRAY_SIZE(twl4030_madc_iio_channels);
> +
>   	/*
>   	 * Phoenix provides 2 interrupt lines. The first one is connected to
>   	 * the OMAP. The other one can be connected to the other processor such
>   	 * as modem. Hence two separate ISR and IMR registers.
>   	 */
> -	madc->imr = (pdata->irq_line == 1) ?
> -	    TWL4030_MADC_IMR1 : TWL4030_MADC_IMR2;
> -	madc->isr = (pdata->irq_line == 1) ?
> -	    TWL4030_MADC_ISR1 : TWL4030_MADC_ISR2;
> +	if (pdata)
> +		madc->use_second_irq = (pdata->irq_line != 1);
> +	else
> +		madc->use_second_irq = of_property_read_bool(np,
> +				       "ti,system-uses-second-madc-irq");
> +
> +	madc->imr = madc->use_second_irq ? TWL4030_MADC_IMR2 :
> +					   TWL4030_MADC_IMR1;
> +	madc->isr = madc->use_second_irq ? TWL4030_MADC_ISR2 :
> +					   TWL4030_MADC_ISR1;
> +
>   	ret = twl4030_madc_set_power(madc, 1);
>   	if (ret < 0)
>   		return ret;
> @@ -768,7 +853,7 @@ static int twl4030_madc_probe(struct platform_device *pdev)
>   		}
>   	}
>
> -	platform_set_drvdata(pdev, madc);
> +	platform_set_drvdata(pdev, iio_dev);
>   	mutex_init(&madc->lock);
>
>   	irq = platform_get_irq(pdev, 0);
> @@ -776,11 +861,19 @@ static int twl4030_madc_probe(struct platform_device *pdev)
>   				   twl4030_madc_threaded_irq_handler,
>   				   IRQF_TRIGGER_RISING, "twl4030_madc", madc);
>   	if (ret) {
> -		dev_dbg(&pdev->dev, "could not request irq\n");
> +		dev_err(&pdev->dev, "could not request irq\n");
>   		goto err_i2c;
>   	}
>   	twl4030_madc = madc;
> +
> +	ret = iio_device_register(iio_dev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "could not register iio device\n");
> +		goto err_i2c;
> +	}
> +
>   	return 0;
> +
>   err_i2c:
>   	twl4030_madc_set_current_generator(madc, 0, 0);
>   err_current_generator:
> @@ -790,20 +883,32 @@ err_current_generator:
>
>   static int twl4030_madc_remove(struct platform_device *pdev)
>   {
> -	struct twl4030_madc_data *madc = platform_get_drvdata(pdev);
> +	struct iio_dev *iio_dev = platform_get_drvdata(pdev);
> +	struct twl4030_madc_data *madc = iio_priv(iio_dev);
>
>   	twl4030_madc_set_current_generator(madc, 0, 0);
>   	twl4030_madc_set_power(madc, 0);
>
Disabling the user interface 'after' turning off the device is a bad idea.
Also as a general rule remove functions should reverse the order of probes.
That way they are obviously right.  Hence this iio_device_unregister needs
to be the first thing in this function I think!
> +	iio_device_unregister(iio_dev);
> +
>   	return 0;
>   }
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id twl_madc_of_match[] = {
> +	{ .compatible = "ti,twl4030-madc", },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, twl_madc_of_match);
> +#endif
> +
>   static struct platform_driver twl4030_madc_driver = {
>   	.probe = twl4030_madc_probe,
>   	.remove = twl4030_madc_remove,
>   	.driver = {
>   		   .name = "twl4030_madc",
>   		   .owner = THIS_MODULE,
> +		   .of_match_table = of_match_ptr(twl_madc_of_match),
>   		   },
>   };
>
>

Re: [PATCHv3 3/9] mfd: twl4030-madc: Cleanup driver

[Jonathan Cameron]

On 10/03/14 17:25, Sebastian Reichel wrote:
> Some style fixes in twl4030-madc driver.
>
> Reported-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Reported-by: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
> Acked-by: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Tested-by: Marek Belisko <marek-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

One, whilst you are here request below.
> ---
>   drivers/mfd/twl4030-madc.c       | 127 +++++++++++++++++++--------------------
>   include/linux/i2c/twl4030-madc.h |   2 +-
>   2 files changed, 62 insertions(+), 67 deletions(-)
>
> diff --git a/drivers/mfd/twl4030-madc.c b/drivers/mfd/twl4030-madc.c
> index 1c5c4db..890d520 100644
> --- a/drivers/mfd/twl4030-madc.c
> +++ b/drivers/mfd/twl4030-madc.c
> @@ -49,22 +49,22 @@
>
>   #include <linux/iio/iio.h>
>
> -/*
> +/**
>    * struct twl4030_madc_data - a container for madc info
> - * @dev - pointer to device structure for madc
> - * @lock - mutex protecting this data structure
> - * @requests - Array of request struct corresponding to SW1, SW2 and RT
> - * @use_second_irq - IRQ selection (main or co-processor)
> - * @imr - Interrupt mask register of MADC
> - * @isr - Interrupt status register of MADC
> + * @dev:		Pointer to device structure for madc
> + * @lock:		Mutex protecting this data structure
> + * @requests:		Array of request struct corresponding to SW1, SW2 and RT
> + * @use_second_irq:	IRQ selection (main or co-processor)
> + * @imr:		Interrupt mask register of MADC
> + * @isr:		Interrupt status register of MADC
>    */
>   struct twl4030_madc_data {
>   	struct device *dev;
>   	struct mutex lock;	/* mutex protecting this data structure */
>   	struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
>   	bool use_second_irq;
> -	int imr;
> -	int isr;
> +	u8 imr;
> +	u8 isr;
>   };
>
>   static int twl4030_madc_read(struct iio_dev *iio_dev,
> @@ -155,17 +155,16 @@ twl4030_divider_ratios[16] = {
>   };
>
>
> -/*
> - * Conversion table from -3 to 55 degree Celcius
> - */
> -static int therm_tbl[] = {
> -30800,	29500,	28300,	27100,
> -26000,	24900,	23900,	22900,	22000,	21100,	20300,	19400,	18700,	17900,
> -17200,	16500,	15900,	15300,	14700,	14100,	13600,	13100,	12600,	12100,
> -11600,	11200,	10800,	10400,	10000,	9630,	9280,	8950,	8620,	8310,
> -8020,	7730,	7460,	7200,	6950,	6710,	6470,	6250,	6040,	5830,
> -5640,	5450,	5260,	5090,	4920,	4760,	4600,	4450,	4310,	4170,
> -4040,	3910,	3790,	3670,	3550
> +/* Conversion table from -3 to 55 degrees Celcius */
> +static int twl4030_therm_tbl[] = {
> +	30800,	29500,	28300,	27100,
> +	26000,	24900,	23900,	22900,	22000,	21100,	20300,	19400,	18700,
> +	17900,	17200,	16500,	15900,	15300,	14700,	14100,	13600,	13100,
> +	12600,	12100,	11600,	11200,	10800,	10400,	10000,	9630,	9280,
> +	8950,	8620,	8310,	8020,	7730,	7460,	7200,	6950,	6710,
> +	6470,	6250,	6040,	5830,	5640,	5450,	5260,	5090,	4920,
> +	4760,	4600,	4450,	4310,	4170,	4040,	3910,	3790,	3670,
> +	3550
>   };
>
>   /*
> @@ -197,11 +196,12 @@ const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = {
>   			      },
>   };
>
> -/*
> - * Function to read a particular channel value.
> - * @madc - pointer to struct twl4030_madc_data
> - * @reg - lsb of ADC Channel
> - * If the i2c read fails it returns an error else returns 0.
> +/**
> + * twl4030_madc_channel_raw_read() - Function to read a particular channel value
> + * @madc:	pointer to struct twl4030_madc_data
> + * @reg:	lsb of ADC Channel
> + *
> + * Return: 0 on success, an error code otherwise.
>    */
>   static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
>   {
> @@ -227,7 +227,7 @@ static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
>   }
>
>   /*
> - * Return battery temperature
> + * Return battery temperature in degrees Celsius
>    * Or < 0 on failure.
>    */
>   static int twl4030battery_temperature(int raw_volt)
> @@ -236,18 +236,18 @@ static int twl4030battery_temperature(int raw_volt)
>   	int temp, curr, volt, res, ret;
>
>   	volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R;
> -	/* Getting and calculating the supply current in micro ampers */
> +	/* Getting and calculating the supply current in micro amperes */
>   	ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val,
>   		REG_BCICTL2);
>   	if (ret < 0)
>   		return ret;
> +
>   	curr = ((val & TWL4030_BCI_ITHEN) + 1) * 10;
>   	/* Getting and calculating the thermistor resistance in ohms */
>   	res = volt * 1000 / curr;
>   	/* calculating temperature */
>   	for (temp = 58; temp >= 0; temp--) {
> -		int actual = therm_tbl[temp];
> -
> +		int actual = twl4030_therm_tbl[temp];
>   		if ((actual - res) >= 0)
>   			break;
>   	}
> @@ -269,11 +269,12 @@ static int twl4030battery_current(int raw_volt)
>   	else /* slope of 0.88 mV/mA */
>   		return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2;
>   }
> +
>   /*
>    * Function to read channel values
>    * @madc - pointer to twl4030_madc_data struct
>    * @reg_base - Base address of the first channel
> - * @Channels - 16 bit bitmap. If the bit is set, channel value is read
> + * @Channels - 16 bit bitmap. If the bit is set, channel's value is read
>    * @buf - The channel values are stored here. if read fails error
>    * @raw - Return raw values without conversion
>    * value is stored
> @@ -284,17 +285,17 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
>   				      long channels, int *buf,
>   				      bool raw)
>   {
> -	int count = 0, count_req = 0, i;
> +	int count = 0;
> +	int i;
>   	u8 reg;
>
>   	for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) {
> -		reg = reg_base + 2 * i;
> +		reg = reg_base + (2 * i);
>   		buf[i] = twl4030_madc_channel_raw_read(madc, reg);
>   		if (buf[i] < 0) {
> -			dev_err(madc->dev,
> -				"Unable to read register 0x%X\n", reg);
> -			count_req++;
> -			continue;
> +			dev_err(madc->dev, "Unable to read register 0x%X\n",
> +				reg);
> +			return buf[i];
>   		}
>   		if (raw) {
>   			count++;
> @@ -305,7 +306,7 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
>   			buf[i] = twl4030battery_current(buf[i]);
>   			if (buf[i] < 0) {
>   				dev_err(madc->dev, "err reading current\n");
> -				count_req++;
> +				return buf[i];
>   			} else {
>   				count++;
>   				buf[i] = buf[i] - 750;
> @@ -315,7 +316,7 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
>   			buf[i] = twl4030battery_temperature(buf[i]);
>   			if (buf[i] < 0) {
>   				dev_err(madc->dev, "err reading temperature\n");
> -				count_req++;
> +				return buf[i];
>   			} else {
>   				buf[i] -= 3;
>   				count++;
> @@ -336,8 +337,6 @@ static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
>   				twl4030_divider_ratios[i].numerator);
>   		}
>   	}
> -	if (count_req)
> -		dev_err(madc->dev, "%d channel conversion failed\n", count_req);
>
>   	return count;
>   }
> @@ -361,13 +360,13 @@ static int twl4030_madc_enable_irq(struct twl4030_madc_data *madc, u8 id)
>   			madc->imr);
>   		return ret;
>   	}
> +
>   	val &= ~(1 << id);
>   	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
>   	if (ret) {
>   		dev_err(madc->dev,
>   			"unable to write imr register 0x%X\n", madc->imr);
>   		return ret;
> -
>   	}
>
>   	return 0;
> @@ -430,7 +429,7 @@ static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc)
>   			continue;
>   		ret = twl4030_madc_disable_irq(madc, i);
>   		if (ret < 0)
> -			dev_dbg(madc->dev, "Disable interrupt failed%d\n", i);
> +			dev_dbg(madc->dev, "Disable interrupt failed %d\n", i);
>   		madc->requests[i].result_pending = 1;
>   	}
>   	for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
> @@ -512,21 +511,17 @@ static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc,
>   {
>   	const struct twl4030_madc_conversion_method *method;
>   	int ret = 0;
> +
> +	if (conv_method != TWL4030_MADC_SW1 && conv_method != TWL4030_MADC_SW2)
> +		return -ENOTSUPP;
> +
>   	method = &twl4030_conversion_methods[conv_method];
> -	switch (conv_method) {
> -	case TWL4030_MADC_SW1:
> -	case TWL4030_MADC_SW2:
> -		ret = twl_i2c_write_u8(TWL4030_MODULE_MADC,
> -				       TWL4030_MADC_SW_START, method->ctrl);
> -		if (ret) {
> -			dev_err(madc->dev,
> -				"unable to write ctrl register 0x%X\n",
> -				method->ctrl);
> -			return ret;
> -		}
> -		break;
> -	default:
> -		break;
> +	ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, TWL4030_MADC_SW_START,
> +			       method->ctrl);
> +	if (ret) {
> +		dev_err(madc->dev, "unable to write ctrl register 0x%X\n",
> +			method->ctrl);
> +		return ret;
>   	}
>
>   	return 0;
> @@ -623,8 +618,8 @@ int twl4030_madc_conversion(struct twl4030_madc_request *req)
>   				       ch_lsb, method->avg);
>   		if (ret) {
>   			dev_err(twl4030_madc->dev,
> -				"unable to write sel reg 0x%X\n",
> -				method->sel + 1);
> +				"unable to write avg reg 0x%X\n",
> +				method->avg);
>   			goto out;
>   		}
>   	}
> @@ -665,10 +660,6 @@ out:
>   }
>   EXPORT_SYMBOL_GPL(twl4030_madc_conversion);
>
> -/*
> - * Return channel value
> - * Or < 0 on failure.
> - */
>   int twl4030_get_madc_conversion(int channel_no)
>   {
>   	struct twl4030_madc_request req;
> @@ -703,6 +694,7 @@ static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
>   					      int chan, int on)
>   {
>   	int ret;
> +	int regmask;
>   	u8 regval;
>
>   	ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE,
> @@ -712,10 +704,13 @@ static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
>   			TWL4030_BCI_BCICTL1);
>   		return ret;
>   	}
> +
> +	regmask = chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
>   	if (on)
> -		regval |= chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
> +		regval |= regmask;
>   	else
> -		regval &= chan ? ~TWL4030_BCI_ITHEN : ~TWL4030_BCI_TYPEN;
> +		regval &= ~regmask;
> +
>   	ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
>   			       regval, TWL4030_BCI_BCICTL1);
>   	if (ret) {
> @@ -730,7 +725,7 @@ static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
Would be nice if this one was also in kernel-doc format :)
>   /*
>    * Function that sets MADC software power on bit to enable MADC
>    * @madc - pointer to twl4030_madc_data struct
> - * @on - Enable or disable MADC software powen on bit.
> + * @on - Enable or disable MADC software power on bit.
>    * returns error if i2c read/write fails else 0
>    */
>   static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on)
> @@ -909,7 +904,7 @@ static struct platform_driver twl4030_madc_driver = {
>   		   .name = "twl4030_madc",
>   		   .owner = THIS_MODULE,
>   		   .of_match_table = of_match_ptr(twl_madc_of_match),
> -		   },
> +	},
>   };
>
>   module_platform_driver(twl4030_madc_driver);
> diff --git a/include/linux/i2c/twl4030-madc.h b/include/linux/i2c/twl4030-madc.h
> index 01f5951..1c0134d 100644
> --- a/include/linux/i2c/twl4030-madc.h
> +++ b/include/linux/i2c/twl4030-madc.h
> @@ -44,7 +44,7 @@ struct twl4030_madc_conversion_method {
>
>   struct twl4030_madc_request {
>   	unsigned long channels;
> -	u16 do_avg;
> +	bool do_avg;
>   	u16 method;
>   	u16 type;
>   	bool active;
>

Re: [PATCHv3 8/9] iio: documentation: Add ABI documentation for *_mean_raw

[Jonathan Cameron]

On 10/03/14 17:25, Sebastian Reichel wrote:
> Add ABI documentation for in_*_mean_raw files, which are
> already supported and used in the kernel for some time.
>
> Signed-off-by: Sebastian Reichel <sre-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org>
As this one stands fine on it's own...

Applied to the togreg branch of iio.git

Thanks
> ---
>   Documentation/ABI/testing/sysfs-bus-iio | 8 ++++++++
>   1 file changed, 8 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> index 6e02c50..58ba333 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio
> +++ b/Documentation/ABI/testing/sysfs-bus-iio
> @@ -210,6 +210,14 @@ Contact:	linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>   Description:
>   		Scaled humidity measurement in milli percent.
>
> +What:		/sys/bus/iio/devices/iio:deviceX/in_X_mean_raw
> +KernelVersion:	3.5
> +Contact:	linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> +Description:
> +		Averaged raw measurement from channel X. The number of values
> +		used for averaging is device specific. The converting rules for
> +		normal raw values also applies to the averaged raw values.
> +
>   What:		/sys/bus/iio/devices/iio:deviceX/in_accel_offset
>   What:		/sys/bus/iio/devices/iio:deviceX/in_accel_x_offset
>   What:		/sys/bus/iio/devices/iio:deviceX/in_accel_y_offset
>

Re: [PATCHv3 9/9] iio: inkern: add iio_read_channel_average_raw

[Jonathan Cameron]

On 10/03/14 17:25, Sebastian Reichel wrote:
> Add iio_read_channel_average_raw to support reading
> averaged raw values in consumer drivers.
>
> Signed-off-by: Sebastian Reichel <sre@debian.org>
As this one also stands fine on it's own and isn't actually used
by the rest of the patch set - applied to the togreg branch of iio.git
This will get pushed out initially as 'testing' for the autobuilders
to play.

Jonathan
> ---
>   drivers/iio/inkern.c         | 18 ++++++++++++++++++
>   include/linux/iio/consumer.h | 13 +++++++++++++
>   2 files changed, 31 insertions(+)
>
> diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
> index 0cf5f8e..adeba5a 100644
> --- a/drivers/iio/inkern.c
> +++ b/drivers/iio/inkern.c
> @@ -443,6 +443,24 @@ err_unlock:
>   }
>   EXPORT_SYMBOL_GPL(iio_read_channel_raw);
>
> +int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
> +{
> +	int ret;
> +
> +	mutex_lock(&chan->indio_dev->info_exist_lock);
> +	if (chan->indio_dev->info == NULL) {
> +		ret = -ENODEV;
> +		goto err_unlock;
> +	}
> +
> +	ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_AVERAGE_RAW);
> +err_unlock:
> +	mutex_unlock(&chan->indio_dev->info_exist_lock);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(iio_read_channel_average_raw);
> +
>   static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
>   	int raw, int *processed, unsigned int scale)
>   {
> diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
> index 2752b1f..651f9a0 100644
> --- a/include/linux/iio/consumer.h
> +++ b/include/linux/iio/consumer.h
> @@ -123,6 +123,19 @@ int iio_read_channel_raw(struct iio_channel *chan,
>   			 int *val);
>
>   /**
> + * iio_read_channel_average_raw() - read from a given channel
> + * @chan:		The channel being queried.
> + * @val:		Value read back.
> + *
> + * Note raw reads from iio channels are in adc counts and hence
> + * scale will need to be applied if standard units required.
> + *
> + * In opposit to the normal iio_read_channel_raw this function
> + * returns the average of multiple reads.
> + */
> +int iio_read_channel_average_raw(struct iio_channel *chan, int *val);
> +
> +/**
>    * iio_read_channel_processed() - read processed value from a given channel
>    * @chan:		The channel being queried.
>    * @val:		Value read back.
>