[PATCH RESEND 2/4] pwm: mediatek: fix clk issue
Zhi Mao
zhi.mao at mediatek.com
Thu Jun 22 05:48:07 PDT 2017
On Wed, 2017-06-21 at 20:07 +0800, John Crispin wrote:
> Hi
>
> comments inline
>
>
> > +static int mtk_pwm_clk_enable(struct pwm_chip *chip, struct pwm_device *pwm)
> > +{
> > + ret = clk_prepare_enable(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
> > + if (ret < 0) {
> > + clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
> > + clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
> > + return ret;
> > + }
> > +
> Rather than disabling the already prepared clks in each error path and
> then returning, you should use goto err_clk_{top,main,pwm1} in the same
> style as what this patch removes from mtk_pwm_probe()
>
> > + return ret;
> > +}
> > static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num,
> > unsigned int offset)
> > {
> > @@ -91,10 +128,12 @@ static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> > if (clkdiv > 7)
> > return -EINVAL;
> >
> > - mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | BIT(3) | clkdiv);
> > + mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | clkdiv);
>
> this chunk needs to go into its own patch
>
> >
> > @@ -102,11 +141,8 @@ static int mtk_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
> > {
> >
> > - ret = clk_prepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
> > - if (ret < 0)
> > - return ret;
> > + mtk_pwm_clk_enable(chip, pwm);
> You need to check the error code here and return if clk enabling failed
>
<....>
Hi John,
For these above comments, I will modified as your suggestions in the
next release.
> >
> >
> > static int mtk_pwm_remove(struct platform_device *pdev)
> > {
> > struct mtk_pwm_chip *pc = platform_get_drvdata(pdev);
> > - unsigned int i;
> > -
> > - for (i = 0; i < pc->chip.npwm; i++)
> > - pwm_disable(&pc->chip.pwms[i]);
> why are you removing this chunk ?
>
> John
>
After refering to some other vendor's pwm driver, we think the
"pwm_disable" is no need, and framework control flow should disable all
the pwms before removing them,
so we remove it.
Regards,
Zhi
> >
> > return pwmchip_remove(&pc->chip);
> > }
>
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