[alsa-devel] ASoC: regmap_config.max_register value wrong?
Dear all,
The following snippet is from the wm8741 codec driver. Shouldn't the .max_register field be set to WM8741_REGISTER_COUNT-1 (10) instead of WM8741_MAX_REGISTER (0x20)?
[...] static const struct regmap_config wm8741_regmap = { .reg_bits = 7, .val_bits = 9, .max_register = WM8741_MAX_REGISTER, [...]
WM8741_MAX_REGISTER is the address of the last register. WM8741_REGISTER_COUNT is the number of registers.
The regmap_config documentation says: "@max_register: Optional, specifies the maximum valid register index."
So it should be the *register index* and not the register address. Do I understand it correctly?
Many thanks in advance. Best regards, Sergej
On 05/25/2015 10:46 PM, Sergej Sawazki wrote:
Dear all,
The following snippet is from the wm8741 codec driver. Shouldn't the .max_register field be set to WM8741_REGISTER_COUNT-1 (10) instead of WM8741_MAX_REGISTER (0x20)?
[...] static const struct regmap_config wm8741_regmap = { .reg_bits = 7, .val_bits = 9, .max_register = WM8741_MAX_REGISTER, [...]
WM8741_MAX_REGISTER is the address of the last register. WM8741_REGISTER_COUNT is the number of registers.
The regmap_config documentation says: "@max_register: Optional, specifies the maximum valid register index."
So it should be the *register index* and not the register address. Do I understand it correctly?
What the documentation means is the index into the physical register map, which is the address. So the code is probably correct.
On Tue, May 26, 2015 at 08:42:58AM +0200, Lars-Peter Clausen wrote:
On 05/25/2015 10:46 PM, Sergej Sawazki wrote:
Dear all,
The following snippet is from the wm8741 codec driver. Shouldn't the .max_register field be set to WM8741_REGISTER_COUNT-1 (10) instead of WM8741_MAX_REGISTER (0x20)?
[...] static const struct regmap_config wm8741_regmap = { .reg_bits = 7, .val_bits = 9, .max_register = WM8741_MAX_REGISTER, [...]
WM8741_MAX_REGISTER is the address of the last register. WM8741_REGISTER_COUNT is the number of registers.
The regmap_config documentation says: "@max_register: Optional, specifies the maximum valid register index."
So it should be the *register index* and not the register address. Do I understand it correctly?
What the documentation means is the index into the physical register map, which is the address. So the code is probably correct.
Yeah the documentation there is maybe not entirely clear here, but the code is correct.
Thanks, Charles
Am 26. Mai 2015 10:14:46 MESZ, schrieb Charles Keepax ckeepax@opensource.wolfsonmicro.com:
On Tue, May 26, 2015 at 08:42:58AM +0200, Lars-Peter Clausen wrote:
On 05/25/2015 10:46 PM, Sergej Sawazki wrote:
Dear all,
The following snippet is from the wm8741 codec driver. Shouldn't the .max_register field be set to WM8741_REGISTER_COUNT-1 (10) instead
of
WM8741_MAX_REGISTER (0x20)?
[...] static const struct regmap_config wm8741_regmap = { .reg_bits = 7, .val_bits = 9, .max_register = WM8741_MAX_REGISTER, [...]
WM8741_MAX_REGISTER is the address of the last register. WM8741_REGISTER_COUNT is the number of registers.
The regmap_config documentation says: "@max_register: Optional, specifies the maximum valid register index."
So it should be the *register index* and not the register address. Do I understand it correctly?
What the documentation means is the index into the physical register
map,
which is the address. So the code is probably correct.
Yeah the documentation there is maybe not entirely clear here, but the code is correct.
Lars-Peter, Charles,
many thanks for your replies.
Sergej
participants (3)
-
Charles Keepax -
Lars-Peter Clausen -
Sergej Sawazki