2024-04-25 17:14:22

by George Stark

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Subject: [PATCH v3 2/3] pwm: meson: Add check for error from clk_round_rate()

clk_round_rate() can return not only zero if requested frequency can not
be provided but also negative error code so add check for it too.

Also change type of variable holding clk_round_rate() result from
unsigned long to long. It's safe due to clk_round_rate() returns long.

Fixes: 329db102a26d ("pwm: meson: make full use of common clock framework")
Signed-off-by: Dmitry Rokosov <[email protected]>
Signed-off-by: George Stark <[email protected]>
---
drivers/pwm/pwm-meson.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index f4d70da621ec..4a652d500dfc 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -148,7 +148,7 @@ static int meson_pwm_calc(struct pwm_chip *chip, struct pwm_device *pwm,
struct meson_pwm *meson = to_meson_pwm(chip);
struct meson_pwm_channel *channel = &meson->channels[pwm->hwpwm];
unsigned int cnt, duty_cnt;
- unsigned long fin_freq;
+ long fin_freq;
u64 duty, period, freq;

duty = state->duty_cycle;
@@ -168,12 +168,13 @@ static int meson_pwm_calc(struct pwm_chip *chip, struct pwm_device *pwm,
freq = ULONG_MAX;

fin_freq = clk_round_rate(channel->clk, freq);
- if (fin_freq == 0) {
- dev_err(pwmchip_parent(chip), "invalid source clock frequency\n");
- return -EINVAL;
+ if (fin_freq <= 0) {
+ dev_err(pwmchip_parent(chip),
+ "invalid source clock frequency %llu\n", freq);
+ return fin_freq ? fin_freq : -EINVAL;
}

- dev_dbg(pwmchip_parent(chip), "fin_freq: %lu Hz\n", fin_freq);
+ dev_dbg(pwmchip_parent(chip), "fin_freq: %ld Hz\n", fin_freq);

cnt = div_u64(fin_freq * period, NSEC_PER_SEC);
if (cnt > 0xffff) {
--
2.25.1