pwm: mediatek: Ensure to disable clocks in error path

commit 505b730ede7f5c4083ff212aa955155b5b92e574 upstream.

After enabling the clocks each error path must disable the clocks again.
One of them failed to do so. Unify the error paths to use goto to make it
harder for future changes to add a similar bug.

Fixes: 7ca59947b5fc ("pwm: mediatek: Prevent divide-by-zero in pwm_mediatek_config()")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250704172728.626815-2-u.kleine-koenig@baylibre.com
Cc: stable@vger.kernel.org
[ukleinek: backported to 6.6.y]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
index 6b1a75b6bd12fb263c87a16bdc13e85e40245661..ff7c70a0033d8a46fb7dd941c60d0e7d263585bc 100644 (file)
--- a/drivers/pwm/pwm-mediatek.c
+++ b/drivers/pwm/pwm-mediatek.c
@@ -133,8 +133,10 @@ static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm,
                return ret;
 
        clk_rate = clk_get_rate(pc->clk_pwms[pwm->hwpwm]);
-       if (!clk_rate)
-               return -EINVAL;
+       if (!clk_rate) {
+               ret = -EINVAL;
+               goto out;
+       }
 
        /* Make sure we use the bus clock and not the 26MHz clock */
        if (pc->soc->has_ck_26m_sel)
@@ -153,9 +155,9 @@ static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm,
        }
 
        if (clkdiv > PWM_CLK_DIV_MAX) {
-               pwm_mediatek_clk_disable(chip, pwm);
                dev_err(chip->dev, "period of %d ns not supported\n", period_ns);
-               return -EINVAL;
+               ret = -EINVAL;
+               goto out;
        }
 
        if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) {
@@ -172,9 +174,10 @@ static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm,
        pwm_mediatek_writel(pc, pwm->hwpwm, reg_width, cnt_period);
        pwm_mediatek_writel(pc, pwm->hwpwm, reg_thres, cnt_duty);
 
+out:
        pwm_mediatek_clk_disable(chip, pwm);
 
-       return 0;
+       return ret;
 }
 
 static int pwm_mediatek_enable(struct pwm_chip *chip, struct pwm_device *pwm)