Commit 6c452cff authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by Thierry Reding
Browse files

pwm: Make .get_state() callback return an error code 



.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.

Reviewed-by: default avatarHeiko Stuebner <heiko@sntech.de>
Reviewed-by: default avatarBaolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: default avatarNeil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: default avatarNobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: default avatarAndre Przywara <andre.przywara@arm.com>
Reviewed-by: default avatarDave Stevenson <dave.stevenson@raspberrypi.com>
Acked-by: default avatarDouglas Anderson <dianders@chromium.org>
Acked-by: default avatarJernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Acked-by: default avatarConor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221130152148.2769768-2-u.kleine-koenig@pengutronix.de


Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 958f0307

drivers/gpio/gpio-mvebu.c

+6 −3
Original line number Diff line number Diff line
@@ -657,9 +657,10 @@ static void mvebu_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) 
	spin_unlock_irqrestore(&mvpwm->lock, flags);

}



static void mvebu_pwm_get_state(struct pwm_chip *chip,

static int mvebu_pwm_get_state(struct pwm_chip *chip,

			       struct pwm_device *pwm,

				struct pwm_state *state) {

			       struct pwm_state *state)

{



	struct mvebu_pwm *mvpwm = to_mvebu_pwm(chip);

	struct mvebu_gpio_chip *mvchip = mvpwm->mvchip;
@@ -693,6 +694,8 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, 
		state->enabled = false;



	spin_unlock_irqrestore(&mvpwm->lock, flags);



	return 0;

}



static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,

drivers/gpu/drm/bridge/ti-sn65dsi86.c

+8 −6
Original line number Diff line number Diff line
@@ -1500,7 +1500,7 @@ static int ti_sn_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, 
	return ret;

}



static void ti_sn_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

static int ti_sn_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

			       struct pwm_state *state)

{

	struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip);
@@ -1512,19 +1512,19 @@ static void ti_sn_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 


	ret = regmap_read(pdata->regmap, SN_PWM_EN_INV_REG, &pwm_en_inv);

	if (ret)

		return;

		return 0;



	ret = ti_sn65dsi86_read_u16(pdata, SN_BACKLIGHT_SCALE_REG, &scale);

	if (ret)

		return;

		return 0;



	ret = ti_sn65dsi86_read_u16(pdata, SN_BACKLIGHT_REG, &backlight);

	if (ret)

		return;

		return 0;



	ret = regmap_read(pdata->regmap, SN_PWM_PRE_DIV_REG, &pre_div);

	if (ret)

		return;

		return 0;



	state->enabled = FIELD_GET(SN_PWM_EN_MASK, pwm_en_inv);

	if (FIELD_GET(SN_PWM_INV_MASK, pwm_en_inv))
@@ -1539,6 +1539,8 @@ static void ti_sn_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 


	if (state->duty_cycle > state->period)

		state->duty_cycle = state->period;



	return 0;

}



static const struct pwm_ops ti_sn_pwm_ops = {

drivers/leds/rgb/leds-qcom-lpg.c

+8 −6
Original line number Diff line number Diff line
@@ -968,7 +968,7 @@ static int lpg_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, 
	return ret;

}



static void lpg_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

static int lpg_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

			     struct pwm_state *state)

{

	struct lpg *lpg = container_of(chip, struct lpg, pwm);
@@ -982,20 +982,20 @@ static void lpg_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 


	ret = regmap_read(lpg->map, chan->base + LPG_SIZE_CLK_REG, &val);

	if (ret)

		return;

		return 0;



	refclk = lpg_clk_rates[val & PWM_CLK_SELECT_MASK];

	if (refclk) {

		ret = regmap_read(lpg->map, chan->base + LPG_PREDIV_CLK_REG, &val);

		if (ret)

			return;

			return 0;



		pre_div = lpg_pre_divs[FIELD_GET(PWM_FREQ_PRE_DIV_MASK, val)];

		m = FIELD_GET(PWM_FREQ_EXP_MASK, val);



		ret = regmap_bulk_read(lpg->map, chan->base + PWM_VALUE_REG, &pwm_value, sizeof(pwm_value));

		if (ret)

			return;

			return 0;



		state->period = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * LPG_RESOLUTION * pre_div * (1 << m), refclk);

		state->duty_cycle = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pwm_value * pre_div * (1 << m), refclk);
@@ -1006,13 +1006,15 @@ static void lpg_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 


	ret = regmap_read(lpg->map, chan->base + PWM_ENABLE_CONTROL_REG, &val);

	if (ret)

		return;

		return 0;



	state->enabled = FIELD_GET(LPG_ENABLE_CONTROL_OUTPUT, val);

	state->polarity = PWM_POLARITY_NORMAL;



	if (state->duty_cycle > state->period)

		state->duty_cycle = state->period;



	return 0;

}



static const struct pwm_ops lpg_pwm_ops = {

drivers/pwm/pwm-atmel.c

+4 −2
Original line number Diff line number Diff line
@@ -356,7 +356,7 @@ static int atmel_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, 
	return 0;

}



static void atmel_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

static int atmel_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

			       struct pwm_state *state)

{

	struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
@@ -396,6 +396,8 @@ static void atmel_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 
		state->polarity = PWM_POLARITY_INVERSED;

	else

		state->polarity = PWM_POLARITY_NORMAL;



	return 0;

}



static const struct pwm_ops atmel_pwm_ops = {

drivers/pwm/pwm-bcm-iproc.c

+5 −3
Original line number Diff line number Diff line
@@ -68,7 +68,7 @@ static void iproc_pwmc_disable(struct iproc_pwmc *ip, unsigned int channel) 
	ndelay(400);

}



static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

static int iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm,

				struct pwm_state *state)

{

	struct iproc_pwmc *ip = to_iproc_pwmc(chip);
@@ -91,7 +91,7 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 
	if (rate == 0) {

		state->period = 0;

		state->duty_cycle = 0;

		return;

		return 0;

	}



	value = readl(ip->base + IPROC_PWM_PRESCALE_OFFSET);
@@ -107,6 +107,8 @@ static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm, 
	value = readl(ip->base + IPROC_PWM_DUTY_CYCLE_OFFSET(pwm->hwpwm));

	tmp = (value & IPROC_PWM_PERIOD_MAX) * multi;

	state->duty_cycle = div64_u64(tmp, rate);



	return 0;

}



static int iproc_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm,