* [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write
@ 2022-06-08 1:08 Xiaohui Zhang
2022-06-08 23:44 ` kernel test robot
2022-06-09 0:14 ` kernel test robot
0 siblings, 2 replies; 6+ messages in thread
From: Xiaohui Zhang @ 2022-06-08 1:08 UTC (permalink / raw)
To: Xiaohui Zhang, Jonathan Cameron, Lars-Peter Clausen,
Gwendal Grignou, Stephen Boyd, Jongpil Jung, linux-iio,
linux-kernel
Similar to the handling of read/write in commit 108e4d4de2b5
("iio:proximity:sx9324: Fix hardware gain read/write"), we thought
a patch might be needed here as well.
There are four possible gain values according to 'sx9360_gain_vals[]':
1, 2, 4, and 8
The values are off by one when writing and reading the register. The
bits should be set according to this equation:
ilog2(<gain>) + 1
so that a gain of 8 is 0x4 in the register field and a gain of 4 is 0x3
in the register field, etc. Note that a gain of 0 is reserved per the
datasheet. The default gain (SX9360_REG_PROX_CTRL0_GAIN_1) is also
wrong. It should be 0x1 << 3, i.e. 0x8, not 0x80 which is setting the
reserved bit 7.
Fix this all up to properly handle the hardware gain and return errors
for invalid settings.
Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
---
drivers/iio/proximity/sx9360.c | 26 +++++++++++++++++++++-----
1 file changed, 21 insertions(+), 5 deletions(-)
diff --git a/drivers/iio/proximity/sx9360.c b/drivers/iio/proximity/sx9360.c
index 3ebb30c8a4f6..3dbcc9f584cf 100644
--- a/drivers/iio/proximity/sx9360.c
+++ b/drivers/iio/proximity/sx9360.c
@@ -64,7 +64,10 @@
#define SX9360_REG_PROX_CTRL0_PHR 0x40
#define SX9360_REG_PROX_CTRL0_PHM 0x41
#define SX9360_REG_PROX_CTRL0_GAIN_MASK GENMASK(5, 3)
-#define SX9360_REG_PROX_CTRL0_GAIN_1 0x80
+#define SX9324_REG_PROX_CTRL0_GAIN_SHIFT 3
+#define SX9324_REG_PROX_CTRL0_GAIN_RSVD 0x0
+#define SX9324_REG_PROX_CTRL0_GAIN_1 0x1
+#define SX9324_REG_PROX_CTRL0_GAIN_8 0x4
#define SX9360_REG_PROX_CTRL0_RAWFILT_MASK GENMASK(2, 0)
#define SX9360_REG_PROX_CTRL0_RAWFILT_1P50 0x01
#define SX9360_REG_PROX_CTRL1 0x42
@@ -288,7 +291,14 @@ static int sx9360_read_gain(struct sx_common_data *data,
if (ret)
return ret;
- *val = 1 << FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
+ regval = FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
+ if (regval)
+ regval--;
+ else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
+ regval > SX9360_REG_PROX_CTRL0_GAIN_8)
+ return -EINVAL;
+
+ *val = 1 << regval;
return IIO_VAL_INT;
}
@@ -630,8 +640,12 @@ static int sx9360_write_gain(struct sx_common_data *data,
unsigned int gain, reg;
int ret;
- gain = ilog2(val);
reg = SX9360_REG_PROX_CTRL0_PHR + chan->channel;
+
+ gain = ilog2(val) + 1;
+ if (val <= 0 || gain > SX9360_REG_PROX_CTRL0_GAIN_8)
+ return -EINVAL;
+
gain = FIELD_PREP(SX9360_REG_PROX_CTRL0_GAIN_MASK, gain);
mutex_lock(&data->mutex);
@@ -681,9 +695,11 @@ static const struct sx_common_reg_default sx9360_default_regs[] = {
{ SX9360_REG_AFE_PARAM1_PHM, SX9360_REG_AFE_PARAM1_AGAIN_PHM_6PF |
SX9360_REG_AFE_PARAM1_FREQ_83_33HZ },
- { SX9360_REG_PROX_CTRL0_PHR, SX9360_REG_PROX_CTRL0_GAIN_1 |
+ { SX9360_REG_PROX_CTRL0_PHR,
+ SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
SX9360_REG_PROX_CTRL0_RAWFILT_1P50 },
- { SX9360_REG_PROX_CTRL0_PHM, SX9360_REG_PROX_CTRL0_GAIN_1 |
+ { SX9360_REG_PROX_CTRL0_PHM,
+ SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
SX9360_REG_PROX_CTRL0_RAWFILT_1P50 },
{ SX9360_REG_PROX_CTRL1, SX9360_REG_PROX_CTRL1_AVGNEG_THRESH_16K },
{ SX9360_REG_PROX_CTRL2, SX9360_REG_PROX_CTRL2_AVGDEB_2SAMPLES |
--
2.17.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write
2022-06-08 1:08 [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write Xiaohui Zhang
@ 2022-06-08 23:44 ` kernel test robot
2022-06-09 0:14 ` kernel test robot
1 sibling, 0 replies; 6+ messages in thread
From: kernel test robot @ 2022-06-08 23:44 UTC (permalink / raw)
To: Xiaohui Zhang, Jonathan Cameron, Lars-Peter Clausen,
Gwendal Grignou, Stephen Boyd, Jongpil Jung, linux-iio,
linux-kernel
Cc: llvm, kbuild-all
Hi Xiaohui,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on jic23-iio/togreg]
[also build test ERROR on v5.19-rc1 next-20220608]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Xiaohui-Zhang/iio-proximity-sx9360-Fix-hardware-gain-read-write/20220608-125912
base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: hexagon-randconfig-r041-20220608 (https://download.01.org/0day-ci/archive/20220609/202206090719.8FcfVgxx-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project b92436efcb7813fc481b30f2593a4907568d917a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/bdc0a6947530604152de0d152635e144a486ee32
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Xiaohui-Zhang/iio-proximity-sx9360-Fix-hardware-gain-read-write/20220608-125912
git checkout bdc0a6947530604152de0d152635e144a486ee32
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/iio/proximity/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
>> drivers/iio/proximity/sx9360.c:297:21: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_RSVD'
else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
^
>> drivers/iio/proximity/sx9360.c:298:13: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_8'
regval > SX9360_REG_PROX_CTRL0_GAIN_8)
^
drivers/iio/proximity/sx9360.c:646:25: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_8'
if (val <= 0 || gain > SX9360_REG_PROX_CTRL0_GAIN_8)
^
>> drivers/iio/proximity/sx9360.c:699:3: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_1'
SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
^
>> drivers/iio/proximity/sx9360.c:699:35: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_SHIFT'
SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
^
drivers/iio/proximity/sx9360.c:702:3: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_1'
SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
^
drivers/iio/proximity/sx9360.c:702:35: error: use of undeclared identifier 'SX9360_REG_PROX_CTRL0_GAIN_SHIFT'
SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
^
>> drivers/iio/proximity/sx9360.c:796:22: error: invalid application of 'sizeof' to an incomplete type 'const struct sx_common_reg_default[]'
.num_default_regs = ARRAY_SIZE(sx9360_default_regs),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/kernel.h:55:32: note: expanded from macro 'ARRAY_SIZE'
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
^~~~~
8 errors generated.
vim +/SX9360_REG_PROX_CTRL0_GAIN_RSVD +297 drivers/iio/proximity/sx9360.c
282
283 static int sx9360_read_gain(struct sx_common_data *data,
284 const struct iio_chan_spec *chan, int *val)
285 {
286 unsigned int reg, regval;
287 int ret;
288
289 reg = SX9360_REG_PROX_CTRL0_PHR + chan->channel;
290 ret = regmap_read(data->regmap, reg, ®val);
291 if (ret)
292 return ret;
293
294 regval = FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
295 if (regval)
296 regval--;
> 297 else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
> 298 regval > SX9360_REG_PROX_CTRL0_GAIN_8)
299 return -EINVAL;
300
301 *val = 1 << regval;
302
303 return IIO_VAL_INT;
304 }
305
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write
2022-06-08 1:08 [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write Xiaohui Zhang
2022-06-08 23:44 ` kernel test robot
@ 2022-06-09 0:14 ` kernel test robot
1 sibling, 0 replies; 6+ messages in thread
From: kernel test robot @ 2022-06-09 0:14 UTC (permalink / raw)
To: Xiaohui Zhang, Jonathan Cameron, Lars-Peter Clausen,
Gwendal Grignou, Stephen Boyd, Jongpil Jung, linux-iio,
linux-kernel
Cc: kbuild-all
Hi Xiaohui,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on jic23-iio/togreg]
[also build test ERROR on v5.19-rc1 next-20220608]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Xiaohui-Zhang/iio-proximity-sx9360-Fix-hardware-gain-read-write/20220608-125912
base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: openrisc-randconfig-r033-20220608 (https://download.01.org/0day-ci/archive/20220609/202206090828.1Q7GljFY-lkp@intel.com/config)
compiler: or1k-linux-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/bdc0a6947530604152de0d152635e144a486ee32
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Xiaohui-Zhang/iio-proximity-sx9360-Fix-hardware-gain-read-write/20220608-125912
git checkout bdc0a6947530604152de0d152635e144a486ee32
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=openrisc SHELL=/bin/bash drivers/iio/proximity/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
drivers/iio/proximity/sx9360.c: In function 'sx9360_read_gain':
>> drivers/iio/proximity/sx9360.c:297:28: error: 'SX9360_REG_PROX_CTRL0_GAIN_RSVD' undeclared (first use in this function); did you mean 'SX9324_REG_PROX_CTRL0_GAIN_RSVD'?
297 | else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| SX9324_REG_PROX_CTRL0_GAIN_RSVD
drivers/iio/proximity/sx9360.c:297:28: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/iio/proximity/sx9360.c:298:27: error: 'SX9360_REG_PROX_CTRL0_GAIN_8' undeclared (first use in this function); did you mean 'SX9324_REG_PROX_CTRL0_GAIN_8'?
298 | regval > SX9360_REG_PROX_CTRL0_GAIN_8)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
| SX9324_REG_PROX_CTRL0_GAIN_8
drivers/iio/proximity/sx9360.c: In function 'sx9360_write_gain':
drivers/iio/proximity/sx9360.c:646:32: error: 'SX9360_REG_PROX_CTRL0_GAIN_8' undeclared (first use in this function); did you mean 'SX9324_REG_PROX_CTRL0_GAIN_8'?
646 | if (val <= 0 || gain > SX9360_REG_PROX_CTRL0_GAIN_8)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
| SX9324_REG_PROX_CTRL0_GAIN_8
drivers/iio/proximity/sx9360.c: At top level:
>> drivers/iio/proximity/sx9360.c:699:17: error: 'SX9360_REG_PROX_CTRL0_GAIN_1' undeclared here (not in a function); did you mean 'SX9324_REG_PROX_CTRL0_GAIN_1'?
699 | SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
| SX9324_REG_PROX_CTRL0_GAIN_1
>> drivers/iio/proximity/sx9360.c:699:49: error: 'SX9360_REG_PROX_CTRL0_GAIN_SHIFT' undeclared here (not in a function); did you mean 'SX9324_REG_PROX_CTRL0_GAIN_SHIFT'?
699 | SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| SX9324_REG_PROX_CTRL0_GAIN_SHIFT
vim +297 drivers/iio/proximity/sx9360.c
282
283 static int sx9360_read_gain(struct sx_common_data *data,
284 const struct iio_chan_spec *chan, int *val)
285 {
286 unsigned int reg, regval;
287 int ret;
288
289 reg = SX9360_REG_PROX_CTRL0_PHR + chan->channel;
290 ret = regmap_read(data->regmap, reg, ®val);
291 if (ret)
292 return ret;
293
294 regval = FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
295 if (regval)
296 regval--;
> 297 else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
> 298 regval > SX9360_REG_PROX_CTRL0_GAIN_8)
299 return -EINVAL;
300
301 *val = 1 << regval;
302
303 return IIO_VAL_INT;
304 }
305
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write
@ 2022-06-10 5:30 Xiaohui Zhang
2022-06-10 14:37 ` Andy Shevchenko
0 siblings, 1 reply; 6+ messages in thread
From: Xiaohui Zhang @ 2022-06-10 5:30 UTC (permalink / raw)
To: Xiaohui Zhang, Jonathan Cameron, Lars-Peter Clausen,
Gwendal Grignou, Stephen Boyd, Jongpil Jung, linux-iio,
linux-kernel
Similar to the handling of read/write in commit 108e4d4de2b5
("iio:proximity:sx9324: Fix hardware gain read/write"), we thought
a patch might be needed here as well.
There are four possible gain values according to 'sx9360_gain_vals[]':
1, 2, 4, and 8
The values are off by one when writing and reading the register. The
bits should be set according to this equation:
ilog2(<gain>) + 1
so that a gain of 8 is 0x4 in the register field and a gain of 4 is 0x3
in the register field, etc. Note that a gain of 0 is reserved per the
datasheet. The default gain (SX9360_REG_PROX_CTRL0_GAIN_1) is also
wrong. It should be 0x1 << 3, i.e. 0x8, not 0x80 which is setting the
reserved bit 7.
Fix this all up to properly handle the hardware gain and return errors
for invalid settings.
Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
---
drivers/iio/proximity/sx9360.c | 26 +++++++++++++++++++++-----
1 file changed, 21 insertions(+), 5 deletions(-)
diff --git a/drivers/iio/proximity/sx9360.c b/drivers/iio/proximity/sx9360.c
index 3ebb30c8a4f6..f231929debb7 100644
--- a/drivers/iio/proximity/sx9360.c
+++ b/drivers/iio/proximity/sx9360.c
@@ -64,7 +64,10 @@
#define SX9360_REG_PROX_CTRL0_PHR 0x40
#define SX9360_REG_PROX_CTRL0_PHM 0x41
#define SX9360_REG_PROX_CTRL0_GAIN_MASK GENMASK(5, 3)
-#define SX9360_REG_PROX_CTRL0_GAIN_1 0x80
+#define SX9360_REG_PROX_CTRL0_GAIN_SHIFT 3
+#define SX9360_REG_PROX_CTRL0_GAIN_RSVD 0x0
+#define SX9360_REG_PROX_CTRL0_GAIN_1 0x1
+#define SX9360_REG_PROX_CTRL0_GAIN_8 0x4
#define SX9360_REG_PROX_CTRL0_RAWFILT_MASK GENMASK(2, 0)
#define SX9360_REG_PROX_CTRL0_RAWFILT_1P50 0x01
#define SX9360_REG_PROX_CTRL1 0x42
@@ -288,7 +291,14 @@ static int sx9360_read_gain(struct sx_common_data *data,
if (ret)
return ret;
- *val = 1 << FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
+ regval = FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
+ if (regval)
+ regval--;
+ else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
+ regval > SX9360_REG_PROX_CTRL0_GAIN_8)
+ return -EINVAL;
+
+ *val = 1 << regval;
return IIO_VAL_INT;
}
@@ -630,8 +640,12 @@ static int sx9360_write_gain(struct sx_common_data *data,
unsigned int gain, reg;
int ret;
- gain = ilog2(val);
reg = SX9360_REG_PROX_CTRL0_PHR + chan->channel;
+
+ gain = ilog2(val) + 1;
+ if (val <= 0 || gain > SX9360_REG_PROX_CTRL0_GAIN_8)
+ return -EINVAL;
+
gain = FIELD_PREP(SX9360_REG_PROX_CTRL0_GAIN_MASK, gain);
mutex_lock(&data->mutex);
@@ -681,9 +695,11 @@ static const struct sx_common_reg_default sx9360_default_regs[] = {
{ SX9360_REG_AFE_PARAM1_PHM, SX9360_REG_AFE_PARAM1_AGAIN_PHM_6PF |
SX9360_REG_AFE_PARAM1_FREQ_83_33HZ },
- { SX9360_REG_PROX_CTRL0_PHR, SX9360_REG_PROX_CTRL0_GAIN_1 |
+ { SX9360_REG_PROX_CTRL0_PHR,
+ SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
SX9360_REG_PROX_CTRL0_RAWFILT_1P50 },
- { SX9360_REG_PROX_CTRL0_PHM, SX9360_REG_PROX_CTRL0_GAIN_1 |
+ { SX9360_REG_PROX_CTRL0_PHM,
+ SX9360_REG_PROX_CTRL0_GAIN_1 << SX9360_REG_PROX_CTRL0_GAIN_SHIFT |
SX9360_REG_PROX_CTRL0_RAWFILT_1P50 },
{ SX9360_REG_PROX_CTRL1, SX9360_REG_PROX_CTRL1_AVGNEG_THRESH_16K },
{ SX9360_REG_PROX_CTRL2, SX9360_REG_PROX_CTRL2_AVGDEB_2SAMPLES |
--
2.17.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write
2022-06-10 5:30 Xiaohui Zhang
@ 2022-06-10 14:37 ` Andy Shevchenko
2022-06-11 16:03 ` Jonathan Cameron
0 siblings, 1 reply; 6+ messages in thread
From: Andy Shevchenko @ 2022-06-10 14:37 UTC (permalink / raw)
To: Xiaohui Zhang
Cc: Jonathan Cameron, Lars-Peter Clausen, Gwendal Grignou,
Stephen Boyd, Jongpil Jung, linux-iio, Linux Kernel Mailing List
On Fri, Jun 10, 2022 at 7:53 AM Xiaohui Zhang <xiaohuizhang@ruc.edu.cn> wrote:
>
> Similar to the handling of read/write in commit 108e4d4de2b5
> ("iio:proximity:sx9324: Fix hardware gain read/write"), we thought
> a patch might be needed here as well.
>
> There are four possible gain values according to 'sx9360_gain_vals[]':
>
> 1, 2, 4, and 8
>
> The values are off by one when writing and reading the register. The
> bits should be set according to this equation:
>
> ilog2(<gain>) + 1
>
> so that a gain of 8 is 0x4 in the register field and a gain of 4 is 0x3
> in the register field, etc. Note that a gain of 0 is reserved per the
> datasheet. The default gain (SX9360_REG_PROX_CTRL0_GAIN_1) is also
> wrong. It should be 0x1 << 3, i.e. 0x8, not 0x80 which is setting the
> reserved bit 7.
>
> Fix this all up to properly handle the hardware gain and return errors
> for invalid settings.
...
> + regval = FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
> + if (regval)
> + regval--;
> + else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
> + regval > SX9360_REG_PROX_CTRL0_GAIN_8)
else?! Isn't it a dead code? How has it been tested?
> + return -EINVAL;
> + *val = 1 << regval;
Even in the original code this is wrong in accordance with C standard.
It might have potentially UB. BIT(), for example, solves this issue.
You may do what it does under the hood.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write
2022-06-10 14:37 ` Andy Shevchenko
@ 2022-06-11 16:03 ` Jonathan Cameron
0 siblings, 0 replies; 6+ messages in thread
From: Jonathan Cameron @ 2022-06-11 16:03 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Xiaohui Zhang, Lars-Peter Clausen, Gwendal Grignou, Stephen Boyd,
Jongpil Jung, linux-iio, Linux Kernel Mailing List
On Fri, 10 Jun 2022 16:37:05 +0200
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
> On Fri, Jun 10, 2022 at 7:53 AM Xiaohui Zhang <xiaohuizhang@ruc.edu.cn> wrote:
> >
> > Similar to the handling of read/write in commit 108e4d4de2b5
> > ("iio:proximity:sx9324: Fix hardware gain read/write"), we thought
> > a patch might be needed here as well.
> >
> > There are four possible gain values according to 'sx9360_gain_vals[]':
> >
> > 1, 2, 4, and 8
> >
> > The values are off by one when writing and reading the register. The
> > bits should be set according to this equation:
> >
> > ilog2(<gain>) + 1
> >
> > so that a gain of 8 is 0x4 in the register field and a gain of 4 is 0x3
> > in the register field, etc. Note that a gain of 0 is reserved per the
> > datasheet. The default gain (SX9360_REG_PROX_CTRL0_GAIN_1) is also
> > wrong. It should be 0x1 << 3, i.e. 0x8, not 0x80 which is setting the
> > reserved bit 7.
> >
> > Fix this all up to properly handle the hardware gain and return errors
> > for invalid settings.
>
> ...
>
> > + regval = FIELD_GET(SX9360_REG_PROX_CTRL0_GAIN_MASK, regval);
> > + if (regval)
> > + regval--;
> > + else if (regval == SX9360_REG_PROX_CTRL0_GAIN_RSVD ||
> > + regval > SX9360_REG_PROX_CTRL0_GAIN_8)
>
> else?! Isn't it a dead code? How has it been tested?
Gah. Missed this in review of sx9324 change. First check is
fine because GAIN_RSVD is 0 though not a lot of point in the if.
Second one is intended as hardening against malicious / broken
hardware only so you would never see that value except via emulation
or a unit test. So test wouldn't have spotted this as far as I
can see.
Needs good old eyeballs. :)
>
> > + return -EINVAL;
>
> > + *val = 1 << regval;
>
> Even in the original code this is wrong in accordance with C standard.
> It might have potentially UB. BIT(), for example, solves this issue.
> You may do what it does under the hood.
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-06-11 15:54 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2022-06-08 1:08 [PATCH 1/1] iio:proximity:sx9360: Fix hardware gain read/write Xiaohui Zhang
2022-06-08 23:44 ` kernel test robot
2022-06-09 0:14 ` kernel test robot
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2022-06-10 5:30 Xiaohui Zhang
2022-06-10 14:37 ` Andy Shevchenko
2022-06-11 16:03 ` Jonathan Cameron
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