Re: [hwmon PATCH v2 4/8] hwmon: (adt7470) Fix swapped PWM3 and PWM4 auto mode masks

[Guenter Roeck]

On Mon, Jul 27, 2026 at 09:22:20PM -0300, Luiz Angelo Daros de Luca wrote:
> The ADT7470_PWM3_AUTO_MASK and ADT7470_PWM4_AUTO_MASK macros are
> currently defined with swapped bit values.
> 
> According to Table 22 of the ADT7470 datasheet, the Fan Control Mode
> Configuration for register 0x69 follows the exact same bit position
> layout as register 0x68:
> - 0x68 Bit[7] corresponds to BHVR1 (PWM1) -> 0x80
> - 0x68 Bit[6] corresponds to BHVR2 (PWM2) -> 0x40
> - 0x69 Bit[7] corresponds to BHVR3 (PWM3) -> 0x80
> - 0x69 Bit[6] corresponds to BHVR4 (PWM4) -> 0x40
> 
> Consequently, PWM3 should use mask 0x80 and PWM4 should use 0x40.
> 
> This typo did not cause any functional bugs because these specific
> macros are never referenced in the driver code. Instead, the driver
> correctly applies the configuration by relying on the modulo parity of
> the channel index (e.g., `channel % 2`) to selectively apply either
> ADT7470_PWM1_AUTO_MASK (0x80) or ADT7470_PWM2_AUTO_MASK (0x40).
> Since the bit layout is identical between the two configuration
> registers, the hardware is currently configured correctly.
> 
> Fix the macro definitions to reflect the datasheet accurately and
> prevent future bugs or confusion during code review and refactoring.
> As this is a purely cosmetic fix with no functional impact, a backport
> to stable kernels is not necessary.
> 
> Fixes: 6f9703d0be16 ("hwmon: add support for adt7470")
> Signed-off-by: Luiz Angelo Daros de Luca <luizluca@xxxxxxxxx>

Applied.

Thanks,
Guenter