Merge tag 'staging-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging/IIO driver updates from Greg KH:
 "Here is the large set of staging and IIO driver changes for 5.8-rc1

  Nothing major, but a lot of new IIO drivers are included in here,
  along with other core iio cleanups and changes.

  On the staging driver front, again, nothing noticable. No new
  deletions or additions, just a ton of tiny cleanups all over the tree
  done by a lot of different people. Most coding style, but many actual
  real fixes and cleanups that are nice to see.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (618 commits)
  staging: rtl8723bs: Use common packet header constants
  staging: sm750fb: Add names to proc_setBLANK args
  staging: most: usb: init return value in default path of switch/case expression
  staging: vchiq: Get rid of VCHIQ_SERVICE_OPENEND callback reason
  staging: vchiq: move vchiq_release_message() into vchiq
  staging: vchi: Get rid of C++ guards
  staging: vchi: Get rid of not implemented function declarations
  staging: vchi: Get rid of vchiq_status_to_vchi()
  staging: vchi: Get rid of vchi_service_set_option()
  staging: vchi: Merge vchi_msg_queue() into vchi_queue_kernel_message()
  staging: vchiq: Move copy callback handling into vchiq
  staging: vchi: Get rid of vchi_queue_user_message()
  staging: vchi: Get rid of vchi_service_destroy()
  staging: most: usb: use function sysfs_streq
  staging: most: usb: add missing put_device calls
  staging: most: usb: use correct error codes
  staging: most: usb: replace code to calculate array index
  staging: most: usb: don't use error path to exit function on success
  staging: most: usb: move allocation of URB out of critical section
  staging: most: usb: return 0 instead of variable
  ...

1 files changed, 14 insertions, 8 deletions

diff --git a/drivers/iio/dac/ad5755.c b/drivers/iio/dac/ad5755.c
index 388ddd14bfd0..7723bd313fc6 100644
--- a/drivers/iio/dac/ad5755.c
+++ b/drivers/iio/dac/ad5755.c
@@ -82,6 +82,7 @@ struct ad5755_chip_info {
  * @pwr_down:	bitmask which contains  hether a channel is powered down or not
  * @ctrl:	software shadow of the channel ctrl registers
  * @channels:	iio channel spec for the device
+ * @lock	lock to protect the data buffer during SPI ops
  * @data:	spi transfer buffers
  */
 struct ad5755_state {
@@ -90,6 +91,7 @@ struct ad5755_state {
 	unsigned int			pwr_down;
 	unsigned int			ctrl[AD5755_NUM_CHANNELS];
 	struct iio_chan_spec		channels[AD5755_NUM_CHANNELS];
+	struct mutex			lock;
 
 	/*
 	 * DMA (thus cache coherency maintenance) requires the
@@ -174,11 +176,12 @@ static int ad5755_write_ctrl_unlocked(struct iio_dev *indio_dev,
 static int ad5755_write(struct iio_dev *indio_dev, unsigned int reg,
 	unsigned int val)
 {
+	struct ad5755_state *st = iio_priv(indio_dev);
 	int ret;
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 	ret = ad5755_write_unlocked(indio_dev, reg, val);
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return ret;
 }
@@ -186,11 +189,12 @@ static int ad5755_write(struct iio_dev *indio_dev, unsigned int reg,
 static int ad5755_write_ctrl(struct iio_dev *indio_dev, unsigned int channel,
 	unsigned int reg, unsigned int val)
 {
+	struct ad5755_state *st = iio_priv(indio_dev);
 	int ret;
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 	ret = ad5755_write_ctrl_unlocked(indio_dev, channel, reg, val);
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return ret;
 }
@@ -211,7 +215,7 @@ static int ad5755_read(struct iio_dev *indio_dev, unsigned int addr)
 		},
 	};
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 
 	st->data[0].d32 = cpu_to_be32(AD5755_READ_FLAG | (addr << 16));
 	st->data[1].d32 = cpu_to_be32(AD5755_NOOP);
@@ -220,7 +224,7 @@ static int ad5755_read(struct iio_dev *indio_dev, unsigned int addr)
 	if (ret >= 0)
 		ret = be32_to_cpu(st->data[1].d32) & 0xffff;
 
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return ret;
 }
@@ -246,7 +250,7 @@ static int ad5755_set_channel_pwr_down(struct iio_dev *indio_dev,
 	struct ad5755_state *st = iio_priv(indio_dev);
 	unsigned int mask = BIT(channel);
 
-	mutex_lock(&indio_dev->mlock);
+	mutex_lock(&st->lock);
 
 	if ((bool)(st->pwr_down & mask) == pwr_down)
 		goto out_unlock;
@@ -266,7 +270,7 @@ static int ad5755_set_channel_pwr_down(struct iio_dev *indio_dev,
 	}
 
 out_unlock:
-	mutex_unlock(&indio_dev->mlock);
+	mutex_unlock(&st->lock);
 
 	return 0;
 }
@@ -746,6 +750,8 @@ static int ad5755_probe(struct spi_device *spi)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->num_channels = AD5755_NUM_CHANNELS;
 
+	mutex_init(&st->lock);
+
 	if (spi->dev.of_node)
 		pdata = ad5755_parse_dt(&spi->dev);
 	else