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* [PATCH] staging: iio: adc: Replace mlock with driver private lock
@ 2017-03-20 14:12 Arushi Singhal
  2017-03-22 20:40 ` Jonathan Cameron
  0 siblings, 1 reply; 3+ messages in thread
From: Arushi Singhal @ 2017-03-20 14:12 UTC (permalink / raw)
  To: lars
  Cc: Michael Hennerich, Jonathan Cameron, Hartmut Knaack,
	Peter Meerwald-Stadler, Greg Kroah-Hartman, linux-iio, devel,
	linux-kernel, outreachy-kernel, lars

The IIO subsystem is redefining iio_dev->mlock to be used by
the IIO core only for protecting device operating mode changes.
ie. Changes between INDIO_DIRECT_MODE, INDIO_BUFFER_* modes.

In this driver, mlock was being used to protect hardware state
changes.  Replace it with a lock in the devices global data.

Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
---
 drivers/staging/iio/adc/ad7606.c | 8 ++++----
 drivers/staging/iio/adc/ad7606.h | 2 ++
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7606.c b/drivers/staging/iio/adc/ad7606.c
index 9dbfa64b1e53..9f529b34e018 100644
--- a/drivers/staging/iio/adc/ad7606.c
+++ b/drivers/staging/iio/adc/ad7606.c
@@ -208,7 +208,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 	switch (mask) {
 	case IIO_CHAN_INFO_SCALE:
 		ret = -EINVAL;
-		mutex_lock(&indio_dev->mlock);
+		mutex_lock(&st->lock);
 		for (i = 0; i < ARRAY_SIZE(scale_avail); i++)
 			if (val2 == scale_avail[i][1]) {
 				gpiod_set_value(st->gpio_range, i);
@@ -217,7 +217,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 				ret = 0;
 				break;
 			}
-		mutex_unlock(&indio_dev->mlock);
+		mutex_unlock(&st->lock);
 
 		return ret;
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
@@ -231,11 +231,11 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 		values[1] = (ret >> 1) & 1;
 		values[2] = (ret >> 2) & 1;
 
-		mutex_lock(&indio_dev->mlock);
+		mutex_lock(&st->lock);
 		gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
 				      values);
 		st->oversampling = val;
-		mutex_unlock(&indio_dev->mlock);
+		mutex_unlock(&st->lock);
 
 		return 0;
 	default:
diff --git a/drivers/staging/iio/adc/ad7606.h b/drivers/staging/iio/adc/ad7606.h
index 746f9553d2ba..5d59bdd78727 100644
--- a/drivers/staging/iio/adc/ad7606.h
+++ b/drivers/staging/iio/adc/ad7606.h
@@ -14,6 +14,7 @@
  * @name:		identification string for chip
  * @channels:		channel specification
  * @num_channels:	number of channels
+ * @lock		protect sensor state
  */
 
 struct ad7606_chip_info {
@@ -37,6 +38,7 @@ struct ad7606_state {
 	bool				done;
 	void __iomem			*base_address;
 
+	struct mutex			lock; /* protect sensor state */
 	struct gpio_desc		*gpio_convst;
 	struct gpio_desc		*gpio_reset;
 	struct gpio_desc		*gpio_range;
-- 
2.11.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* [PATCH] staging: iio: adc: Replace mlock with driver private lock
@ 2017-03-12 20:45 Gargi Sharma
  0 siblings, 0 replies; 3+ messages in thread
From: Gargi Sharma @ 2017-03-12 20:45 UTC (permalink / raw)
  To: outreachy-kernel
  Cc: lars, Michael.Hennerich, jic23, knaack.h, pmeerw, linux-iio,
	Gargi Sharma

The IIO subsystem is redefining iio_dev->mlock to be used by
the IIO core only for protecting device operating mode changes.
ie. Changes between INDIO_DIRECT_MODE, INDIO_BUFFER_* modes.

In this driver, mlock was being used to protect hardware state
changes.  Replace it with a lock in the devices global data.
This was done using Coccinelle Script.

@r1@
identifier xxx_state;
@@
struct xxx_state {
...
+ struct mutex          lock; /* protect sensor state */
};

@r2@
expression e;
@@
- mutex_lock(e);
+ mutex_lock(&st->lock);

@r3@
expression e;
@@
- mutex_unlock(e);
+ mutex_unlock(&st->lock);

Signed-off-by: Gargi Sharma <gs051095@gmail.com>
---
 drivers/staging/iio/adc/ad7280a.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7280a.c b/drivers/staging/iio/adc/ad7280a.c
index ee679ac..27a3ce3 100644
--- a/drivers/staging/iio/adc/ad7280a.c
+++ b/drivers/staging/iio/adc/ad7280a.c
@@ -136,6 +136,7 @@ struct ad7280_state {
 	unsigned char			cb_mask[AD7280A_MAX_CHAIN];
 
 	__be32				buf[2] ____cacheline_aligned;
+	struct mutex			lock;  /* protect sensor state */
 };
 
 static void ad7280_crc8_build_table(unsigned char *crc_tab)
@@ -410,7 +411,7 @@ static ssize_t ad7280_store_balance_sw(struct device *dev,
 	devaddr = this_attr->address >> 8;
 	ch = this_attr->address & 0xFF;
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 	if (readin)
 		st->cb_mask[devaddr] |= 1 << (ch + 2);
 	else
@@ -418,7 +419,7 @@ static ssize_t ad7280_store_balance_sw(struct device *dev,
 
 	ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
 			   0, st->cb_mask[devaddr]);
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return ret ? ret : len;
 }
@@ -433,10 +434,10 @@ static ssize_t ad7280_show_balance_timer(struct device *dev,
 	int ret;
 	unsigned int msecs;
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 	ret = ad7280_read(st, this_attr->address >> 8,
 			  this_attr->address & 0xFF);
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	if (ret < 0)
 		return ret;
@@ -466,11 +467,11 @@ static ssize_t ad7280_store_balance_timer(struct device *dev,
 	if (val > 31)
 		return -EINVAL;
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 	ret = ad7280_write(st, this_attr->address >> 8,
 			   this_attr->address & 0xFF,
 			   0, (val & 0x1F) << 3);
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return ret ? ret : len;
 }
@@ -655,7 +656,7 @@ static ssize_t ad7280_write_channel_config(struct device *dev,
 
 	val = clamp(val, 0L, 0xFFL);
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 	switch ((u32)this_attr->address) {
 	case AD7280A_CELL_OVERVOLTAGE:
 		st->cell_threshhigh = val;
@@ -674,7 +675,7 @@ static ssize_t ad7280_write_channel_config(struct device *dev,
 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
 			   this_attr->address, 1, val);
 
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return ret ? ret : len;
 }
@@ -792,13 +793,13 @@ static int ad7280_read_raw(struct iio_dev *indio_dev,
 
 	switch (m) {
 	case IIO_CHAN_INFO_RAW:
-		mutex_lock(&indio_dev->mlock);
+		mutex_lock(&st->lock);
 		if (chan->address == AD7280A_ALL_CELLS)
 			ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
 		else
 			ret = ad7280_read_channel(st, chan->address >> 8,
 						  chan->address & 0xFF);
-		mutex_unlock(&indio_dev->mlock);
+		mutex_unlock(&st->lock);
 
 		if (ret < 0)
 			return ret;
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2017-03-22 20:40 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2017-03-20 14:12 [PATCH] staging: iio: adc: Replace mlock with driver private lock Arushi Singhal
2017-03-22 20:40 ` Jonathan Cameron
  -- strict thread matches above, loose matches on Subject: below --
2017-03-12 20:45 Gargi Sharma

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