Re: [PATCH 3/4] mfd: stm32-timers: Drop TIM_DIER_CC_IE(x) in favour of TIM_DIER_CCxIE(x)

[Lee Jones <lee@kernel.org>]

On Fri, 14 Jun 2024, Uwe Kleine-König wrote:

> These two defines have the same purpose and this change doesn't
> introduce any differences in drivers/counter/stm32-timer-cnt.o.
> 
> The only difference between the two is that
> 
> 	TIM_DIER_CC_IE(1) == TIM_DIER_CC2IE
> 
> while
> 
> 	TIM_DIER_CCxIE(1) == TIM_DIER_CC1IE
> 
> . That makes it necessary to have an explicit "+ 1" in the user code,
> but IMHO this is a good thing as this is the code locatation that
> "knows" that for software channel 1 you have to use TIM_DIER_CC2IE
> (because software guys start counting at 0, while the relevant hardware
> designer started at 1).
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/counter/stm32-timer-cnt.c | 4 ++--

The subject should be renamed.

>  include/linux/mfd/stm32-timers.h  | 1 -
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c
> index 0664ef969f79..186e73d6ccb4 100644
> --- a/drivers/counter/stm32-timer-cnt.c
> +++ b/drivers/counter/stm32-timer-cnt.c
> @@ -465,7 +465,7 @@ static int stm32_count_events_configure(struct counter_device *counter)
>  			ret = stm32_count_capture_configure(counter, event_node->channel, true);
>  			if (ret)
>  				return ret;
> -			dier |= TIM_DIER_CC_IE(event_node->channel);
> +			dier |= TIM_DIER_CCxIE(event_node->channel + 1);
>  			break;
>  		default:
>  			/* should never reach this path */
> @@ -478,7 +478,7 @@ static int stm32_count_events_configure(struct counter_device *counter)
>  
>  	/* check for disabled capture events */
>  	for (i = 0 ; i < priv->nchannels; i++) {
> -		if (!(dier & TIM_DIER_CC_IE(i))) {
> +		if (!(dier & TIM_DIER_CCxIE(i + 1))) {
>  			ret = stm32_count_capture_configure(counter, i, false);
>  			if (ret)
>  				return ret;
> diff --git a/include/linux/mfd/stm32-timers.h b/include/linux/mfd/stm32-timers.h
> index 92b45a559656..f09ba598c97a 100644
> --- a/include/linux/mfd/stm32-timers.h
> +++ b/include/linux/mfd/stm32-timers.h
> @@ -47,7 +47,6 @@
>  #define TIM_DIER_CC2IE		TIM_DIER_CCxIE(2)			/* CC2 Interrupt Enable				*/
>  #define TIM_DIER_CC3IE		TIM_DIER_CCxIE(3)			/* CC3 Interrupt Enable				*/
>  #define TIM_DIER_CC4IE		TIM_DIER_CCxIE(4)			/* CC4 Interrupt Enable				*/
> -#define TIM_DIER_CC_IE(x)	BIT((x) + 1)				/* CC1, CC2, CC3, CC4 interrupt enable		*/
>  #define TIM_DIER_UDE		BIT(8)					/* Update DMA request Enable			*/
>  #define TIM_DIER_CCxDE(x)	BIT(9 + ((x) - 1))			/* CCx DMA request Enable (x ∈ {1, .. 4})	*/
>  #define TIM_DIER_CC1DE		TIM_DIER_CCxDE(1)			/* CC1 DMA request Enable			*/
> -- 
> 2.43.0
> 

-- 
Lee Jones [李琼斯]