Hi Boris， 在 2017/3/1 18:19, Boris Brezillon 写道:
On Wed, 1 Mar 2017 18:16:02 +0800 David Wu <david.wu@xxxxxxxxxxxxxx> wrote:From: "david.wu" <david.wu@xxxxxxxxxxxxxx> If the pwm was not enabled at uboot loader, pwm could not work for clock always disabled at pwm driver. The pwm clock is enabled at beginning of pwm_apply(), but disabled at end of pwm_apply(). If the pwm was enabled at uboot loader, pwm clock is always enabled unless closed by ATF. The pwm-backlight might turn off the power at early suspend, should disable pwm clock for saving power consume. It is important to provide opportunity to enable/disable clock at pwm driver, the pwm consumer should ensure correct order to call pwm enable/disable, and pwm driver ensure state of pwm clock synchronized with pwm enabled state. Fixes: 2bf1c98aa5a4 ("pwm: rockchip: Add support for atomic update") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: David Wu <david.wu@xxxxxxxxxxxxxx> Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> --- drivers/pwm/pwm-rockchip.c | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-) diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c index ef89df1..dbee3c3 100644 --- a/drivers/pwm/pwm-rockchip.c +++ b/drivers/pwm/pwm-rockchip.c @@ -191,6 +191,28 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } +static int rk_pwm_enable(struct pwm_chip *chip, + struct pwm_device *pwm, + bool enable, + enum pwm_polarity polarity)You didn't change the function name: s/rk_pwm_enable/rockchip_pwm_enable/
Sorry, it is a pity not to fix in in v2.
+{ + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + int ret; + + if (enable) { + ret = clk_enable(pc->clk); + if (ret) + return ret; + } + + pc->data->set_enable(chip, pwm, enable, polarity); + + if (!enable) + clk_disable(pc->clk); + + return 0; +} + static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state) { @@ -207,22 +229,26 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return ret; if (state->polarity != curstate.polarity && enabled) { - pc->data->set_enable(chip, pwm, false, state->polarity); + ret = rk_pwm_enable(chip, pwm, false, state->polarity); + if (ret) + goto out; enabled = false; } ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period); if (ret) { if (enabled != curstate.enabled) - pc->data->set_enable(chip, pwm, !enabled, - state->polarity); - + rk_pwm_enable(chip, pwm, !enabled, + state->polarity); goto out; } - if (state->enabled != enabled) - pc->data->set_enable(chip, pwm, state->enabled, - state->polarity); + if (state->enabled != enabled) { + ret = rk_pwm_enable(chip, pwm, state->enabled, + state->polarity); + if (ret) + goto out; + } /* * Update the state with the real hardware, which can differ a bit