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authorAndre Przywara <andre.przywara@arm.com>2022-12-02 19:35:37 +0100
committerThierry Reding <thierry.reding@gmail.com>2022-12-06 12:46:30 +0100
commita08b318a155e77d4c61bbdc28248b347d66f7248 (patch)
tree056410bc36dfeeccc4cf633e853788ddebae753f /drivers/pwm
parentpwm: Handle .get_state() failures (diff)
downloadlinux-a08b318a155e77d4c61bbdc28248b347d66f7248.tar.xz
linux-a08b318a155e77d4c61bbdc28248b347d66f7248.zip
pwm: sun4i: Propagate errors in .get_state() to the caller
.get_state() can return an error indication now. Make use of it to propagate an impossible prescaler encoding, should that have sneaked in somehow. Also check the return value of clk_get_rate(). That's unlikely to fail, but we use that in two divide operations down in the code, so let's avoid a divide-by-zero condition on the way. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Samuel Holland <samuel@sholland.org> Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com> Link: https://lore.kernel.org/r/20221201152223.3133-1-andre.przywara@arm.com Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-sun4i.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index 37d75e252d4e..b973da73e9ab 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -118,6 +118,8 @@ static int sun4i_pwm_get_state(struct pwm_chip *chip,
unsigned int prescaler;
clk_rate = clk_get_rate(sun4i_pwm->clk);
+ if (!clk_rate)
+ return -EINVAL;
val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
@@ -142,7 +144,7 @@ static int sun4i_pwm_get_state(struct pwm_chip *chip,
prescaler = prescaler_table[PWM_REG_PRESCAL(val, pwm->hwpwm)];
if (prescaler == 0)
- return 0;
+ return -EINVAL;
if (val & BIT_CH(PWM_ACT_STATE, pwm->hwpwm))
state->polarity = PWM_POLARITY_NORMAL;