On Wed, 30 Nov 2022 16:21:38 +0100
Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> wrote:
Hi,
> .get_state() might fail in some cases. To make it possible that a driver
> signals such a failure change the prototype of .get_state() to return an
> error code.
>
> This patch was created using coccinelle and the following semantic patch:
>
> @p1@
> identifier getstatefunc;
> identifier driver;
> @@
> struct pwm_ops driver = {
> ...,
> .get_state = getstatefunc
> ,...
> };
>
> @p2@
> identifier p1.getstatefunc;
> identifier chip, pwm, state;
> @@
> -void
> +int
> getstatefunc(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state)
> {
> ...
> - return;
> + return 0;
> ...
> }
>
> plus the actual change of the prototype in include/linux/pwm.h (plus some
> manual fixing of indentions and empty lines).
>
> So for now all drivers return success unconditionally. They are adapted
> in the following patches to make the changes easier reviewable.
>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
> ---
> drivers/gpio/gpio-mvebu.c | 9 ++++++---
> drivers/gpu/drm/bridge/ti-sn65dsi86.c | 14 ++++++++------
> drivers/leds/rgb/leds-qcom-lpg.c | 14 ++++++++------
> drivers/pwm/pwm-atmel.c | 6 ++++--
> drivers/pwm/pwm-bcm-iproc.c | 8 +++++---
> drivers/pwm/pwm-crc.c | 10 ++++++----
> drivers/pwm/pwm-cros-ec.c | 8 +++++---
> drivers/pwm/pwm-dwc.c | 6 ++++--
> drivers/pwm/pwm-hibvt.c | 6 ++++--
> drivers/pwm/pwm-imx-tpm.c | 8 +++++---
> drivers/pwm/pwm-imx27.c | 8 +++++---
> drivers/pwm/pwm-intel-lgm.c | 6 ++++--
> drivers/pwm/pwm-iqs620a.c | 6 ++++--
> drivers/pwm/pwm-keembay.c | 6 ++++--
> drivers/pwm/pwm-lpss.c | 6 ++++--
> drivers/pwm/pwm-meson.c | 8 +++++---
> drivers/pwm/pwm-mtk-disp.c | 12 +++++++-----
> drivers/pwm/pwm-pca9685.c | 8 +++++---
> drivers/pwm/pwm-raspberrypi-poe.c | 8 +++++---
> drivers/pwm/pwm-rockchip.c | 12 +++++++-----
> drivers/pwm/pwm-sifive.c | 6 ++++--
> drivers/pwm/pwm-sl28cpld.c | 8 +++++---
> drivers/pwm/pwm-sprd.c | 8 +++++---
> drivers/pwm/pwm-stm32-lp.c | 8 +++++---
> drivers/pwm/pwm-sun4i.c | 12 +++++++-----
> drivers/pwm/pwm-sunplus.c | 6 ++++--
> drivers/pwm/pwm-visconti.c | 6 ++++--
> drivers/pwm/pwm-xilinx.c | 8 +++++---
> include/linux/pwm.h | 4 ++--
> 29 files changed, 146 insertions(+), 89 deletions(-)
>
[ ... ]
> diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
> index c8445b0a3339..37d75e252d4e 100644
> --- a/drivers/pwm/pwm-sun4i.c
> +++ b/drivers/pwm/pwm-sun4i.c
> @@ -108,9 +108,9 @@ static inline void sun4i_pwm_writel(struct sun4i_pwm_chip *chip,
> writel(val, chip->base + offset);
> }
>
> -static void sun4i_pwm_get_state(struct pwm_chip *chip,
> - struct pwm_device *pwm,
> - struct pwm_state *state)
> +static int sun4i_pwm_get_state(struct pwm_chip *chip,
> + struct pwm_device *pwm,
> + struct pwm_state *state)
> {
> struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip);
> u64 clk_rate, tmp;
> @@ -132,7 +132,7 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip,
> state->duty_cycle = DIV_ROUND_UP_ULL(state->period, 2);
> state->polarity = PWM_POLARITY_NORMAL;
> state->enabled = true;
> - return;
> + return 0;
> }
>
> if ((PWM_REG_PRESCAL(val, pwm->hwpwm) == PWM_PRESCAL_MASK) &&
> @@ -142,7 +142,7 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip,
> prescaler = prescaler_table[PWM_REG_PRESCAL(val, pwm->hwpwm)];
>
> if (prescaler == 0)
> - return;
> + return 0;
>
> if (val & BIT_CH(PWM_ACT_STATE, pwm->hwpwm))
> state->polarity = PWM_POLARITY_NORMAL;
> @@ -162,6 +162,8 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip,
>
> tmp = (u64)prescaler * NSEC_PER_SEC * PWM_REG_PRD(val);
> state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
> +
> + return 0;
> }
>
> static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm,
For sunxi:
Reviewed-by: Andre Przywara <andre.przywara@xxxxxxx>
Just one comment: I don't see a sunxi specific patch later in the series,
though it seems we have at least one error error exit (see prescaler == 0
above). Plus potentially another exit if clk_get_rate() (at the very
beginning) fails.
Shall I send a patch for that?
Cheers,
Andre.
