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

From: Lee Jones
Date: Fri Jun 14 2024 - 05:31:37 EST


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@xxxxxxxxxxxx>
> ---
> 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]