drivers/base/regmap/regmap-i2c.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
i2c_smbus_write_word_data() expects a plain u16, but cpu_to_le16()
returns __le16 (a sparse-restricted endian type), causing:
drivers/base/regmap/regmap-i2c.c:340: sparse: incorrect type in
argument 3 (different base types)
expected unsigned short [usertype] value
got restricted __le16 [usertype]
SMBus already defines byte ordering internally, so cpu_to_le16() is
wrong here. Replace it with a plain (u16) cast.
Fixes: bad4bd28abf4 ("regmap-i2c: add SMBus byte/word reg16 bus for adapters lacking I2C_FUNC_I2C")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202605161621.mY5zFh4D-lkp@intel.com/
Signed-off-by: Nishanth Sampath Kumar <nissampa@cisco.com>
---
drivers/base/regmap/regmap-i2c.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/base/regmap/regmap-i2c.c b/drivers/base/regmap/regmap-i2c.c
index 31e30dfced19..ae441fc63127 100644
--- a/drivers/base/regmap/regmap-i2c.c
+++ b/drivers/base/regmap/regmap-i2c.c
@@ -337,7 +337,7 @@ static int regmap_smbus_word_write_reg16(void *context, const void *data,
val = ((u8 *)data)[2];
return i2c_smbus_write_word_data(i2c, addr_hi,
- cpu_to_le16(((u16)val << 8) | addr_lo));
+ ((u16)val << 8) | addr_lo));
}
static const struct regmap_bus regmap_smbus_byte_word_reg16 = {
--
2.25.1Hi Nishanth,
kernel test robot noticed the following build errors:
[auto build test ERROR on broonie-regmap/for-next]
[also build test ERROR on linus/master v7.1-rc4 next-20260519]
[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#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Nishanth-Sampath-Kumar/regmap-i2c-fix-sparse-warning-in-regmap_smbus_word_write_reg16/20260520-011137
base: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next
patch link: https://lore.kernel.org/r/20260519170836.1344260-1-nissampa%40cisco.com
patch subject: [PATCH] regmap-i2c: fix sparse warning in regmap_smbus_word_write_reg16
config: s390-randconfig-r071-20260520 (https://download.01.org/0day-ci/archive/20260520/202605200654.DSWKrX9W-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 8.5.0
smatch: v0.5.0-9185-gbcc58b9c
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260520/202605200654.DSWKrX9W-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605200654.DSWKrX9W-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/base/regmap/regmap-i2c.c: In function 'regmap_smbus_word_write_reg16':
>> drivers/base/regmap/regmap-i2c.c:340:33: error: expected ';' before ')' token
((u16)val << 8) | addr_lo));
^
;
>> drivers/base/regmap/regmap-i2c.c:340:33: error: expected statement before ')' token
vim +340 drivers/base/regmap/regmap-i2c.c
305
306 /*
307 * SMBus byte/word reg16 support for adapters that have SMBUS_BYTE_DATA
308 * and SMBUS_WORD_DATA but lack I2C_FUNC_I2C and I2C_FUNC_SMBUS_I2C_BLOCK,
309 * such as the AMD PIIX4.
310 *
311 * READ: set 16-bit EEPROM address via write_byte_data(addr_lo, addr_hi),
312 * then sequentially read bytes via read_byte() (EEPROM auto-
313 * increments the address pointer). Same as the I2C-block reg16
314 * read path above.
315 *
316 * WRITE: encode the low address byte and data into a word transaction:
317 * write_word_data(addr_hi, (data_byte << 8) | addr_lo).
318 * Only single-byte writes are supported (one value per transaction).
319 */
320 static int regmap_smbus_word_write_reg16(void *context, const void *data,
321 size_t count)
322 {
323 struct device *dev = context;
324 struct i2c_client *i2c = to_i2c_client(dev);
325 u8 addr_hi, addr_lo, val;
326
327 /*
328 * data layout: [addr_hi, addr_lo, val0, val1, ...].
329 * Only single-byte value writes are supported; multi-byte would
330 * require raw I2C (or repeated word writes with incrementing address).
331 */
332 if (count != 3)
333 return -EINVAL;
334
335 addr_hi = ((u8 *)data)[0];
336 addr_lo = ((u8 *)data)[1];
337 val = ((u8 *)data)[2];
338
339 return i2c_smbus_write_word_data(i2c, addr_hi,
> 340 ((u16)val << 8) | addr_lo));
341 }
342
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Nishanth,
kernel test robot noticed the following build errors:
[auto build test ERROR on broonie-regmap/for-next]
[also build test ERROR on linus/master v7.1-rc4 next-20260519]
[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#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Nishanth-Sampath-Kumar/regmap-i2c-fix-sparse-warning-in-regmap_smbus_word_write_reg16/20260520-011137
base: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next
patch link: https://lore.kernel.org/r/20260519170836.1344260-1-nissampa%40cisco.com
patch subject: [PATCH] regmap-i2c: fix sparse warning in regmap_smbus_word_write_reg16
config: arm64-randconfig-004-20260520 (https://download.01.org/0day-ci/archive/20260520/202605200528.vTiSwokq-lkp@intel.com/config)
compiler: clang version 16.0.6 (https://github.com/llvm/llvm-project 7cbf1a2591520c2491aa35339f227775f4d3adf6)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260520/202605200528.vTiSwokq-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605200528.vTiSwokq-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/base/regmap/regmap-i2c.c:340:33: error: expected ';' after return statement
((u16)val << 8) | addr_lo));
^
;
1 error generated.
vim +340 drivers/base/regmap/regmap-i2c.c
305
306 /*
307 * SMBus byte/word reg16 support for adapters that have SMBUS_BYTE_DATA
308 * and SMBUS_WORD_DATA but lack I2C_FUNC_I2C and I2C_FUNC_SMBUS_I2C_BLOCK,
309 * such as the AMD PIIX4.
310 *
311 * READ: set 16-bit EEPROM address via write_byte_data(addr_lo, addr_hi),
312 * then sequentially read bytes via read_byte() (EEPROM auto-
313 * increments the address pointer). Same as the I2C-block reg16
314 * read path above.
315 *
316 * WRITE: encode the low address byte and data into a word transaction:
317 * write_word_data(addr_hi, (data_byte << 8) | addr_lo).
318 * Only single-byte writes are supported (one value per transaction).
319 */
320 static int regmap_smbus_word_write_reg16(void *context, const void *data,
321 size_t count)
322 {
323 struct device *dev = context;
324 struct i2c_client *i2c = to_i2c_client(dev);
325 u8 addr_hi, addr_lo, val;
326
327 /*
328 * data layout: [addr_hi, addr_lo, val0, val1, ...].
329 * Only single-byte value writes are supported; multi-byte would
330 * require raw I2C (or repeated word writes with incrementing address).
331 */
332 if (count != 3)
333 return -EINVAL;
334
335 addr_hi = ((u8 *)data)[0];
336 addr_lo = ((u8 *)data)[1];
337 val = ((u8 *)data)[2];
338
339 return i2c_smbus_write_word_data(i2c, addr_hi,
> 340 ((u16)val << 8) | addr_lo));
341 }
342
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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