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authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2021-06-21 14:21:48 +0200
committerLee Jones <lee.jones@linaro.org>2021-06-22 15:11:37 +0200
commit1181f2164135d770bdad297290b73d274787389b (patch)
tree134fa16640e815f05d3fd83be8be8a027f6ea9f8 /drivers/video
parentbacklight: lm3630a: Fix return code of .update_status() callback (diff)
downloadlinux-1181f2164135d770bdad297290b73d274787389b.tar.xz
linux-1181f2164135d770bdad297290b73d274787389b.zip
backlight: lm3630a: Convert to atomic PWM API and check for errors
The practical upside here is that this only needs a single API call to program the hardware which (depending on the underlaying hardware) can be more effective and prevents glitches. Up to now the return value of the pwm functions was ignored. Fix this and propagate the error to the caller. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/backlight/lm3630a_bl.c42
1 files changed, 19 insertions, 23 deletions
diff --git a/drivers/video/backlight/lm3630a_bl.c b/drivers/video/backlight/lm3630a_bl.c
index 419b0334cf08..e8b185bb6f5e 100644
--- a/drivers/video/backlight/lm3630a_bl.c
+++ b/drivers/video/backlight/lm3630a_bl.c
@@ -52,6 +52,7 @@ struct lm3630a_chip {
struct gpio_desc *enable_gpio;
struct regmap *regmap;
struct pwm_device *pwmd;
+ struct pwm_state pwmd_state;
};
/* i2c access */
@@ -167,16 +168,19 @@ static int lm3630a_intr_config(struct lm3630a_chip *pchip)
return rval;
}
-static void lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
+static int lm3630a_pwm_ctrl(struct lm3630a_chip *pchip, int br, int br_max)
{
- unsigned int period = pchip->pdata->pwm_period;
- unsigned int duty = br * period / br_max;
+ int err;
- pwm_config(pchip->pwmd, duty, period);
- if (duty)
- pwm_enable(pchip->pwmd);
- else
- pwm_disable(pchip->pwmd);
+ pchip->pwmd_state.period = pchip->pdata->pwm_period;
+
+ err = pwm_set_relative_duty_cycle(&pchip->pwmd_state, br, br_max);
+ if (err)
+ return err;
+
+ pchip->pwmd_state.enabled = pchip->pwmd_state.duty_cycle ? true : false;
+
+ return pwm_apply_state(pchip->pwmd, &pchip->pwmd_state);
}
/* update and get brightness */
@@ -187,11 +191,9 @@ static int lm3630a_bank_a_update_status(struct backlight_device *bl)
enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
/* pwm control */
- if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
- lm3630a_pwm_ctrl(pchip, bl->props.brightness,
- bl->props.max_brightness);
- return 0;
- }
+ if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0)
+ return lm3630a_pwm_ctrl(pchip, bl->props.brightness,
+ bl->props.max_brightness);
/* disable sleep */
ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
@@ -264,11 +266,9 @@ static int lm3630a_bank_b_update_status(struct backlight_device *bl)
enum lm3630a_pwm_ctrl pwm_ctrl = pchip->pdata->pwm_ctrl;
/* pwm control */
- if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
- lm3630a_pwm_ctrl(pchip, bl->props.brightness,
- bl->props.max_brightness);
- return 0;
- }
+ if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0)
+ return lm3630a_pwm_ctrl(pchip, bl->props.brightness,
+ bl->props.max_brightness);
/* disable sleep */
ret = lm3630a_update(pchip, REG_CTRL, 0x80, 0x00);
@@ -565,11 +565,7 @@ static int lm3630a_probe(struct i2c_client *client,
return PTR_ERR(pchip->pwmd);
}
- /*
- * FIXME: pwm_apply_args() should be removed when switching to
- * the atomic PWM API.
- */
- pwm_apply_args(pchip->pwmd);
+ pwm_init_state(pchip->pwmd, &pchip->pwmd_state);
}
/* interrupt enable : irq 0 is not allowed */