Re: [PATCH] pwm: atmel: add missing clk_disable_unprepare()

From: claudiu beznea
Date: Wed Aug 23 2023 - 00:59:17 EST




On 8/22/23 10:04, Hari Prasath Gujulan Elango wrote:
> Fix the below smatch warning:
>
> drivers/pwm/pwm-atmel-hlcdc.c:167 atmel_hlcdc_pwm_apply() warn: 'new_clk' from clk_prepare_enable() not released on lines: 112,137,142,149.
>

Can you add a fixes tag?

> Signed-off-by: Hari Prasath Gujulan Elango <Hari.PrasathGE@xxxxxxxxxxxxx>
> ---
> drivers/pwm/pwm-atmel-hlcdc.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
> index 96a709a9d49a..ce46f6c74a14 100644
> --- a/drivers/pwm/pwm-atmel-hlcdc.c
> +++ b/drivers/pwm/pwm-atmel-hlcdc.c
> @@ -108,8 +108,10 @@ static int atmel_hlcdc_pwm_apply(struct pwm_chip *c, struct pwm_device *pwm,
> ATMEL_HLCDC_CFG(0),
> ATMEL_HLCDC_CLKPWMSEL,
> gencfg);
> - if (ret)
> + if (ret) {
> + clk_disable_unprepare(new_clk);
> return ret;
> + }
> }
>
> do_div(pwmcval, state->period);
> @@ -133,20 +135,27 @@ static int atmel_hlcdc_pwm_apply(struct pwm_chip *c, struct pwm_device *pwm,
> ATMEL_HLCDC_PWMPS_MASK |
> ATMEL_HLCDC_PWMPOL,
> pwmcfg);
> - if (ret)
> + if (ret) {
> + clk_disable_unprepare(new_clk);
> return ret;
> + }
>
> ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_EN,
> ATMEL_HLCDC_PWM);
> - if (ret)
> + if (ret) {
> + clk_disable_unprepare(new_clk);
> return ret;
> + }
>
> ret = regmap_read_poll_timeout(hlcdc->regmap, ATMEL_HLCDC_SR,
> status,
> status & ATMEL_HLCDC_PWM,
> 10, 0);
> - if (ret)
> + if (ret) {
> + clk_disable_unprepare(new_clk);

Can you keep a single failure point for all these?

Also, you have to set chip->cur_clk = NULL otherwise next time your apply
will get executed the new_clk will not be enabled.

Thank you,
Claudiu Beznea

> return ret;
> + }
> +
> } else {
> ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_DIS,
> ATMEL_HLCDC_PWM);