2017-03-19 21:00:43

by Simran Singhal

[permalink] [raw]
Subject: [PATCH v6] staging: Use buf_lock instead of mlock and Refactor code

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 buf_lock in the devices global data.

As buf_lock protects both the adis16060_spi_write() and
adis16060_spi_read() functions and both are always called in
pair. First write, then read. Thus, refactor the code to have
one single function adis16060_spi_write_than_read() which is
protected by the existing buf_lock.

Removed nested locks as the function adis16060_read_raw call
a lock on &st->buf_lock and then calls the function
adis16060_spi_write which again tries to get hold
of the same lock.

Signed-off-by: simran singhal <[email protected]>
---

v6:
-Change commit message
-Remove nested lock

drivers/staging/iio/gyro/adis16060_core.c | 40 ++++++++++---------------------
1 file changed, 13 insertions(+), 27 deletions(-)

diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c
index c9d46e7..1c6de46 100644
--- a/drivers/staging/iio/gyro/adis16060_core.c
+++ b/drivers/staging/iio/gyro/adis16060_core.c
@@ -40,25 +40,17 @@ struct adis16060_state {

static struct iio_dev *adis16060_iio_dev;

-static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val)
+static int adis16060_spi_write_than_read(struct iio_dev *indio_dev,
+ u8 conf, u16 *val)
{
int ret;
struct adis16060_state *st = iio_priv(indio_dev);

- mutex_lock(&st->buf_lock);
- st->buf[2] = val; /* The last 8 bits clocked in are latched */
+ st->buf[2] = conf; /* The last 8 bits clocked in are latched */
ret = spi_write(st->us_w, st->buf, 3);
- mutex_unlock(&st->buf_lock);
-
- return ret;
-}
-
-static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
-{
- int ret;
- struct adis16060_state *st = iio_priv(indio_dev);

- mutex_lock(&st->buf_lock);
+ if (ret < 0)
+ return ret;

ret = spi_read(st->us_r, st->buf, 3);

@@ -69,8 +61,8 @@ static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
*/
if (!ret)
*val = ((st->buf[0] & 0x3) << 12) |
- (st->buf[1] << 4) |
- ((st->buf[2] >> 4) & 0xF);
+ (st->buf[1] << 4) |
+ ((st->buf[2] >> 4) & 0xF);
mutex_unlock(&st->buf_lock);

return ret;
@@ -83,20 +75,18 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
{
u16 tval = 0;
int ret;
+ struct adis16060_state *st = iio_priv(indio_dev);

switch (mask) {
case IIO_CHAN_INFO_RAW:
/* Take the iio_dev status lock */
- mutex_lock(&indio_dev->mlock);
- ret = adis16060_spi_write(indio_dev, chan->address);
+ mutex_lock(&st->buf_lock);
+ ret = adis16060_spi_write_than_read(indio_dev,
+ chan->address, &tval);
+ mutex_unlock(&st->buf_lock);
if (ret < 0)
- goto out_unlock;
+ return ret;

- ret = adis16060_spi_read(indio_dev, &tval);
- if (ret < 0)
- goto out_unlock;
-
- mutex_unlock(&indio_dev->mlock);
*val = tval;
return IIO_VAL_INT;
case IIO_CHAN_INFO_OFFSET:
@@ -110,10 +100,6 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
}

return -EINVAL;
-
-out_unlock:
- mutex_unlock(&indio_dev->mlock);
- return ret;
}

static const struct iio_info adis16060_info = {
--
2.7.4


2017-03-21 16:49:34

by Alison Schofield

[permalink] [raw]
Subject: Re: [Outreachy kernel] [PATCH v6] staging: Use buf_lock instead of mlock and Refactor code

On Mon, Mar 20, 2017 at 01:36:21AM +0530, simran singhal wrote:

Hi Simran,

I going to ask for a v7 without looking at the code ;)
Subject line needs subsystem and driver.
Subject and log message can be improved.

> 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 buf_lock in the devices global data.
^^^^^^^^^^^ this was not done
>
> As buf_lock protects both the adis16060_spi_write() and
> adis16060_spi_read() functions and both are always called in
> pair. First write, then read. Thus, refactor the code to have
> one single function adis16060_spi_write_than_read() which is
> protected by the existing buf_lock.
This was done. So, you were able to obsolete the need for mlock
by creating the paired function.

>
> Removed nested locks as the function adis16060_read_raw call
> a lock on &st->buf_lock and then calls the function
> adis16060_spi_write which again tries to get hold
> of the same lock.
^^^^ this was not done. Yes, you avoided nested locks through
proper coding, but we don't want to give the impression in the
log message that there was a pre-existing nested lock issue.

I did checkpatch & compile it...but looked no further yet.

alisons
>
> Signed-off-by: simran singhal <[email protected]>
> ---
>
> v6:
> -Change commit message
> -Remove nested lock
>
> drivers/staging/iio/gyro/adis16060_core.c | 40 ++++++++++---------------------
> 1 file changed, 13 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c
> index c9d46e7..1c6de46 100644
> --- a/drivers/staging/iio/gyro/adis16060_core.c
> +++ b/drivers/staging/iio/gyro/adis16060_core.c
> @@ -40,25 +40,17 @@ struct adis16060_state {
>
> static struct iio_dev *adis16060_iio_dev;
>
> -static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val)
> +static int adis16060_spi_write_than_read(struct iio_dev *indio_dev,
> + u8 conf, u16 *val)
> {
> int ret;
> struct adis16060_state *st = iio_priv(indio_dev);
>
> - mutex_lock(&st->buf_lock);
> - st->buf[2] = val; /* The last 8 bits clocked in are latched */
> + st->buf[2] = conf; /* The last 8 bits clocked in are latched */
> ret = spi_write(st->us_w, st->buf, 3);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret;
> -}
> -
> -static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
> -{
> - int ret;
> - struct adis16060_state *st = iio_priv(indio_dev);
>
> - mutex_lock(&st->buf_lock);
> + if (ret < 0)
> + return ret;
>
> ret = spi_read(st->us_r, st->buf, 3);
>
> @@ -69,8 +61,8 @@ static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
> */
> if (!ret)
> *val = ((st->buf[0] & 0x3) << 12) |
> - (st->buf[1] << 4) |
> - ((st->buf[2] >> 4) & 0xF);
> + (st->buf[1] << 4) |
> + ((st->buf[2] >> 4) & 0xF);
> mutex_unlock(&st->buf_lock);
>
> return ret;
> @@ -83,20 +75,18 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
> {
> u16 tval = 0;
> int ret;
> + struct adis16060_state *st = iio_priv(indio_dev);
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> /* Take the iio_dev status lock */
> - mutex_lock(&indio_dev->mlock);
> - ret = adis16060_spi_write(indio_dev, chan->address);
> + mutex_lock(&st->buf_lock);
> + ret = adis16060_spi_write_than_read(indio_dev,
> + chan->address, &tval);
> + mutex_unlock(&st->buf_lock);
> if (ret < 0)
> - goto out_unlock;
> + return ret;
>
> - ret = adis16060_spi_read(indio_dev, &tval);
> - if (ret < 0)
> - goto out_unlock;
> -
> - mutex_unlock(&indio_dev->mlock);
> *val = tval;
> return IIO_VAL_INT;
> case IIO_CHAN_INFO_OFFSET:
> @@ -110,10 +100,6 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
> }
>
> return -EINVAL;
> -
> -out_unlock:
> - mutex_unlock(&indio_dev->mlock);
> - return ret;
> }
>
> static const struct iio_info adis16060_info = {
> --
> 2.7.4
>
> --
> You received this message because you are subscribed to the Google Groups "outreachy-kernel" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> To post to this group, send email to [email protected].
> To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/20170319200621.GA21295%40singhal-Inspiron-5558.
> For more options, visit https://groups.google.com/d/optout.

2017-03-21 17:05:23

by Simran Singhal

[permalink] [raw]
Subject: Re: [Outreachy kernel] [PATCH v6] staging: Use buf_lock instead of mlock and Refactor code

On Tue, Mar 21, 2017 at 10:18 PM, Alison Schofield <[email protected]> wrote:
> On Mon, Mar 20, 2017 at 01:36:21AM +0530, simran singhal wrote:
>
> Hi Simran,
>
> I going to ask for a v7 without looking at the code ;)
> Subject line needs subsystem and driver.
> Subject and log message can be improved.

Hi Alison,
I have already sent v7 with changed subject.

>
>> 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 buf_lock in the devices global data.
> ^^^^^^^^^^^ this was not done
>>
>> As buf_lock protects both the adis16060_spi_write() and
>> adis16060_spi_read() functions and both are always called in
>> pair. First write, then read. Thus, refactor the code to have
>> one single function adis16060_spi_write_than_read() which is
>> protected by the existing buf_lock.
> This was done. So, you were able to obsolete the need for mlock
> by creating the paired function.
>
>>
>> Removed nested locks as the function adis16060_read_raw call
>> a lock on &st->buf_lock and then calls the function
>> adis16060_spi_write which again tries to get hold
>> of the same lock.
> ^^^^ this was not done. Yes, you avoided nested locks through
> proper coding, but we don't want to give the impression in the
> log message that there was a pre-existing nested lock issue.
>
> I did checkpatch & compile it...but looked no further yet.
>
> alisons
>>
>> Signed-off-by: simran singhal <[email protected]>
>> ---
>>
>> v6:
>> -Change commit message
>> -Remove nested lock
>>
>> drivers/staging/iio/gyro/adis16060_core.c | 40 ++++++++++---------------------
>> 1 file changed, 13 insertions(+), 27 deletions(-)
>>
>> diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c
>> index c9d46e7..1c6de46 100644
>> --- a/drivers/staging/iio/gyro/adis16060_core.c
>> +++ b/drivers/staging/iio/gyro/adis16060_core.c
>> @@ -40,25 +40,17 @@ struct adis16060_state {
>>
>> static struct iio_dev *adis16060_iio_dev;
>>
>> -static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val)
>> +static int adis16060_spi_write_than_read(struct iio_dev *indio_dev,
>> + u8 conf, u16 *val)
>> {
>> int ret;
>> struct adis16060_state *st = iio_priv(indio_dev);
>>
>> - mutex_lock(&st->buf_lock);
>> - st->buf[2] = val; /* The last 8 bits clocked in are latched */
>> + st->buf[2] = conf; /* The last 8 bits clocked in are latched */
>> ret = spi_write(st->us_w, st->buf, 3);
>> - mutex_unlock(&st->buf_lock);
>> -
>> - return ret;
>> -}
>> -
>> -static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
>> -{
>> - int ret;
>> - struct adis16060_state *st = iio_priv(indio_dev);
>>
>> - mutex_lock(&st->buf_lock);
>> + if (ret < 0)
>> + return ret;
>>
>> ret = spi_read(st->us_r, st->buf, 3);
>>
>> @@ -69,8 +61,8 @@ static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
>> */
>> if (!ret)
>> *val = ((st->buf[0] & 0x3) << 12) |
>> - (st->buf[1] << 4) |
>> - ((st->buf[2] >> 4) & 0xF);
>> + (st->buf[1] << 4) |
>> + ((st->buf[2] >> 4) & 0xF);
>> mutex_unlock(&st->buf_lock);
>>
>> return ret;
>> @@ -83,20 +75,18 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
>> {
>> u16 tval = 0;
>> int ret;
>> + struct adis16060_state *st = iio_priv(indio_dev);
>>
>> switch (mask) {
>> case IIO_CHAN_INFO_RAW:
>> /* Take the iio_dev status lock */
>> - mutex_lock(&indio_dev->mlock);
>> - ret = adis16060_spi_write(indio_dev, chan->address);
>> + mutex_lock(&st->buf_lock);
>> + ret = adis16060_spi_write_than_read(indio_dev,
>> + chan->address, &tval);
>> + mutex_unlock(&st->buf_lock);
>> if (ret < 0)
>> - goto out_unlock;
>> + return ret;
>>
>> - ret = adis16060_spi_read(indio_dev, &tval);
>> - if (ret < 0)
>> - goto out_unlock;
>> -
>> - mutex_unlock(&indio_dev->mlock);
>> *val = tval;
>> return IIO_VAL_INT;
>> case IIO_CHAN_INFO_OFFSET:
>> @@ -110,10 +100,6 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
>> }
>>
>> return -EINVAL;
>> -
>> -out_unlock:
>> - mutex_unlock(&indio_dev->mlock);
>> - return ret;
>> }
>>
>> static const struct iio_info adis16060_info = {
>> --
>> 2.7.4
>>
>> --
>> You received this message because you are subscribed to the Google Groups "outreachy-kernel" group.
>> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
>> To post to this group, send email to [email protected].
>> To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/20170319200621.GA21295%40singhal-Inspiron-5558.
>> For more options, visit https://groups.google.com/d/optout.

2017-03-21 17:47:24

by Alison Schofield

[permalink] [raw]
Subject: Re: [Outreachy kernel] [PATCH v6] staging: Use buf_lock instead of mlock and Refactor code

On Tue, Mar 21, 2017 at 10:34:01PM +0530, SIMRAN SINGHAL wrote:
> On Tue, Mar 21, 2017 at 10:18 PM, Alison Schofield <[email protected]> wrote:
> > On Mon, Mar 20, 2017 at 01:36:21AM +0530, simran singhal wrote:
> >
> > Hi Simran,
> >
> > I going to ask for a v7 without looking at the code ;)
> > Subject line needs subsystem and driver.
> > Subject and log message can be improved.
>
> Hi Alison,
> I have already sent v7 with changed subject.

Simran,
I see v7. Needs subsystem (iio) and to nitpick, driver name
is "adis16060" ;) Other comments still apply.
Please append all version histories below the --- for review.
v7:
v6:
.
.
v2:
thanks,
alisons
>
> >
> >> 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 buf_lock in the devices global data.
> > ^^^^^^^^^^^ this was not done
> >>
> >> As buf_lock protects both the adis16060_spi_write() and
> >> adis16060_spi_read() functions and both are always called in
> >> pair. First write, then read. Thus, refactor the code to have
> >> one single function adis16060_spi_write_than_read() which is
> >> protected by the existing buf_lock.
> > This was done. So, you were able to obsolete the need for mlock
> > by creating the paired function.
> >
> >>
> >> Removed nested locks as the function adis16060_read_raw call
> >> a lock on &st->buf_lock and then calls the function
> >> adis16060_spi_write which again tries to get hold
> >> of the same lock.
> > ^^^^ this was not done. Yes, you avoided nested locks through
> > proper coding, but we don't want to give the impression in the
> > log message that there was a pre-existing nested lock issue.
> >
> > I did checkpatch & compile it...but looked no further yet.
> >
> > alisons
> >>
> >> Signed-off-by: simran singhal <[email protected]>
> >> ---
> >>
> >> v6:
> >> -Change commit message
> >> -Remove nested lock
> >>
> >> drivers/staging/iio/gyro/adis16060_core.c | 40 ++++++++++---------------------
> >> 1 file changed, 13 insertions(+), 27 deletions(-)
> >>
> >> diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c
> >> index c9d46e7..1c6de46 100644
> >> --- a/drivers/staging/iio/gyro/adis16060_core.c
> >> +++ b/drivers/staging/iio/gyro/adis16060_core.c
> >> @@ -40,25 +40,17 @@ struct adis16060_state {
> >>
> >> static struct iio_dev *adis16060_iio_dev;
> >>
> >> -static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val)
> >> +static int adis16060_spi_write_than_read(struct iio_dev *indio_dev,
> >> + u8 conf, u16 *val)
> >> {
> >> int ret;
> >> struct adis16060_state *st = iio_priv(indio_dev);
> >>
> >> - mutex_lock(&st->buf_lock);
> >> - st->buf[2] = val; /* The last 8 bits clocked in are latched */
> >> + st->buf[2] = conf; /* The last 8 bits clocked in are latched */
> >> ret = spi_write(st->us_w, st->buf, 3);
> >> - mutex_unlock(&st->buf_lock);
> >> -
> >> - return ret;
> >> -}
> >> -
> >> -static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
> >> -{
> >> - int ret;
> >> - struct adis16060_state *st = iio_priv(indio_dev);
> >>
> >> - mutex_lock(&st->buf_lock);
> >> + if (ret < 0)
> >> + return ret;
> >>
> >> ret = spi_read(st->us_r, st->buf, 3);
> >>
> >> @@ -69,8 +61,8 @@ static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
> >> */
> >> if (!ret)
> >> *val = ((st->buf[0] & 0x3) << 12) |
> >> - (st->buf[1] << 4) |
> >> - ((st->buf[2] >> 4) & 0xF);
> >> + (st->buf[1] << 4) |
> >> + ((st->buf[2] >> 4) & 0xF);
> >> mutex_unlock(&st->buf_lock);
> >>
> >> return ret;
> >> @@ -83,20 +75,18 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
> >> {
> >> u16 tval = 0;
> >> int ret;
> >> + struct adis16060_state *st = iio_priv(indio_dev);
> >>
> >> switch (mask) {
> >> case IIO_CHAN_INFO_RAW:
> >> /* Take the iio_dev status lock */
> >> - mutex_lock(&indio_dev->mlock);
> >> - ret = adis16060_spi_write(indio_dev, chan->address);
> >> + mutex_lock(&st->buf_lock);
> >> + ret = adis16060_spi_write_than_read(indio_dev,
> >> + chan->address, &tval);
> >> + mutex_unlock(&st->buf_lock);
> >> if (ret < 0)
> >> - goto out_unlock;
> >> + return ret;
> >>
> >> - ret = adis16060_spi_read(indio_dev, &tval);
> >> - if (ret < 0)
> >> - goto out_unlock;
> >> -
> >> - mutex_unlock(&indio_dev->mlock);
> >> *val = tval;
> >> return IIO_VAL_INT;
> >> case IIO_CHAN_INFO_OFFSET:
> >> @@ -110,10 +100,6 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
> >> }
> >>
> >> return -EINVAL;
> >> -
> >> -out_unlock:
> >> - mutex_unlock(&indio_dev->mlock);
> >> - return ret;
> >> }
> >>
> >> static const struct iio_info adis16060_info = {
> >> --
> >> 2.7.4
> >>
> >> --
> >> You received this message because you are subscribed to the Google Groups "outreachy-kernel" group.
> >> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> >> To post to this group, send email to [email protected].
> >> To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/20170319200621.GA21295%40singhal-Inspiron-5558.
> >> For more options, visit https://groups.google.com/d/optout.

2017-03-21 18:36:11

by Simran Singhal

[permalink] [raw]
Subject: Re: [Outreachy kernel] [PATCH v6] staging: Use buf_lock instead of mlock and Refactor code

On Tue, Mar 21, 2017 at 10:18 PM, Alison Schofield <[email protected]> wrote:
> On Mon, Mar 20, 2017 at 01:36:21AM +0530, simran singhal wrote:
>
> Hi Simran,
>
> I going to ask for a v7 without looking at the code ;)
> Subject line needs subsystem and driver.
> Subject and log message can be improved.
>
>> 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 buf_lock in the devices global data.
> ^^^^^^^^^^^ this was not done
>>
>> As buf_lock protects both the adis16060_spi_write() and
>> adis16060_spi_read() functions and both are always called in
>> pair. First write, then read. Thus, refactor the code to have
>> one single function adis16060_spi_write_than_read() which is
>> protected by the existing buf_lock.
> This was done. So, you were able to obsolete the need for mlock
> by creating the paired function.

I am still using mlock but now locking it and performing both write and
read and than unlocking.

So, now have a single safe function.

>
>>
>> Removed nested locks as the function adis16060_read_raw call
>> a lock on &st->buf_lock and then calls the function
>> adis16060_spi_write which again tries to get hold
>> of the same lock.
> ^^^^ this was not done. Yes, you avoided nested locks through
> proper coding, but we don't want to give the impression in the
> log message that there was a pre-existing nested lock issue.
>
> I did checkpatch & compile it...but looked no further yet.
>
> alisons
>>
>> Signed-off-by: simran singhal <[email protected]>
>> ---
>>
>> v6:
>> -Change commit message
>> -Remove nested lock
>>
>> drivers/staging/iio/gyro/adis16060_core.c | 40 ++++++++++---------------------
>> 1 file changed, 13 insertions(+), 27 deletions(-)
>>
>> diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c
>> index c9d46e7..1c6de46 100644
>> --- a/drivers/staging/iio/gyro/adis16060_core.c
>> +++ b/drivers/staging/iio/gyro/adis16060_core.c
>> @@ -40,25 +40,17 @@ struct adis16060_state {
>>
>> static struct iio_dev *adis16060_iio_dev;
>>
>> -static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val)
>> +static int adis16060_spi_write_than_read(struct iio_dev *indio_dev,
>> + u8 conf, u16 *val)
>> {
>> int ret;
>> struct adis16060_state *st = iio_priv(indio_dev);
>>
>> - mutex_lock(&st->buf_lock);
>> - st->buf[2] = val; /* The last 8 bits clocked in are latched */
>> + st->buf[2] = conf; /* The last 8 bits clocked in are latched */
>> ret = spi_write(st->us_w, st->buf, 3);
>> - mutex_unlock(&st->buf_lock);
>> -
>> - return ret;
>> -}
>> -
>> -static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
>> -{
>> - int ret;
>> - struct adis16060_state *st = iio_priv(indio_dev);
>>
>> - mutex_lock(&st->buf_lock);
>> + if (ret < 0)
>> + return ret;
>>
>> ret = spi_read(st->us_r, st->buf, 3);
>>
>> @@ -69,8 +61,8 @@ static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val)
>> */
>> if (!ret)
>> *val = ((st->buf[0] & 0x3) << 12) |
>> - (st->buf[1] << 4) |
>> - ((st->buf[2] >> 4) & 0xF);
>> + (st->buf[1] << 4) |
>> + ((st->buf[2] >> 4) & 0xF);
>> mutex_unlock(&st->buf_lock);
>>
>> return ret;
>> @@ -83,20 +75,18 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
>> {
>> u16 tval = 0;
>> int ret;
>> + struct adis16060_state *st = iio_priv(indio_dev);
>>
>> switch (mask) {
>> case IIO_CHAN_INFO_RAW:
>> /* Take the iio_dev status lock */
>> - mutex_lock(&indio_dev->mlock);
>> - ret = adis16060_spi_write(indio_dev, chan->address);
>> + mutex_lock(&st->buf_lock);
>> + ret = adis16060_spi_write_than_read(indio_dev,
>> + chan->address, &tval);
>> + mutex_unlock(&st->buf_lock);
>> if (ret < 0)
>> - goto out_unlock;
>> + return ret;
>>
>> - ret = adis16060_spi_read(indio_dev, &tval);
>> - if (ret < 0)
>> - goto out_unlock;
>> -
>> - mutex_unlock(&indio_dev->mlock);
>> *val = tval;
>> return IIO_VAL_INT;
>> case IIO_CHAN_INFO_OFFSET:
>> @@ -110,10 +100,6 @@ static int adis16060_read_raw(struct iio_dev *indio_dev,
>> }
>>
>> return -EINVAL;
>> -
>> -out_unlock:
>> - mutex_unlock(&indio_dev->mlock);
>> - return ret;
>> }
>>
>> static const struct iio_info adis16060_info = {
>> --
>> 2.7.4
>>
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