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pwm: sun4i: Move pwm_calculate() out of spin_lock()

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pwm_calculate() calls clk_get_rate() while holding a spin_lock().

This create an issue as clk_get_rate() may sleep.

Move pwm_calculate() out of this spin_lock().

Fixes: c32c5c50d4 ("pwm: sun4i: Switch to atomic PWM")
Reported-by: Alexander Finger <alex.mobigo@gmail.com>
Sugested-by: Vasily Khoruzhick <anarsoul@gmail.com>
Tested-by: Alexander Finger <alex.mobigo@gmail.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Clément Péron 2020-01-13 10:23:13 +01:00 committed by Thierry Reding
parent 9f2919e9b4
commit 3e954d9626
1 changed files with 3 additions and 4 deletions
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7
drivers/pwm/pwm-sun4i.c
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@ -248,19 +248,18 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
}
}
spin_lock(&sun4i_pwm->ctrl_lock);
ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
ret = sun4i_pwm_calculate(sun4i_pwm, state, &duty, &period, &prescaler,
&bypass);
if (ret) {
dev_err(chip->dev, "period exceeds the maximum value\n");
spin_unlock(&sun4i_pwm->ctrl_lock);
if (!cstate.enabled)
clk_disable_unprepare(sun4i_pwm->clk);
return ret;
}
spin_lock(&sun4i_pwm->ctrl_lock);
ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
if (sun4i_pwm->data->has_direct_mod_clk_output) {
if (bypass) {
ctrl |= BIT_CH(PWM_BYPASS, pwm->hwpwm);