OrgACRN
/
acrn-kernel
mirror of https://github.com/projectacrn/acrn-kernel.git
1
0
Fork 0
Code Issues Releases Wiki Activity

pwm: sun4i: Remove erroneous else branch 

Commit d3817a6470 ("pwm: sun4i: Remove redundant needs_delay") changed
the logic of an else branch so that the PWM_EN and PWM_CLK_GATING bits
are now cleared if the PWM is to be disabled, whereas previously the
condition was always false, and hence the branch never got executed.

This code is reported causing backlight issues on boards based on the
Allwinner A20 SoC. Fix this by removing the else branch, which restores
the behaviour prior to the offending commit.

Note that the PWM_EN and PWM_CLK_GATING bits still get cleared later in
sun4i_pwm_apply() if the PWM is to be disabled.

Fixes: d3817a6470 ("pwm: sun4i: Remove redundant needs_delay")
Reported-by: Taras Galchenko <tpgalchenko@gmail.com>
Suggested-by: Taras Galchenko <tpgalchenko@gmail.com>
Tested-by: Taras Galchenko <tpgalchenko@gmail.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Thierry Reding 2020-12-16 18:33:55 +01:00
parent edf7f80e78
commit 6eefb79d6f
1 changed files with 1 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/pwm/pwm-sun4i.c
View File

@ -294,12 +294,8 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
ctrl |= BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
if (state->enabled) {
if (state->enabled)
ctrl |= BIT_CH(PWM_EN, pwm->hwpwm);
} else {
ctrl &= ~BIT_CH(PWM_EN, pwm->hwpwm);
ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
}
sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG);