pwm: meson: fix handling of period/duty if greater than UINT_MAX

commit 87a2cbf02d7701255f9fcca7e5bd864a7bb397cf upstream.

state->period/duty are of type u64, and if their value is greater than
UINT_MAX, then the cast to uint will cause problems. Fix this by
changing the type of the respective local variables to u64.

Fixes: b79c3670e120 ("pwm: meson: Don't duplicate the polarity internally")
Cc: stable@vger.kernel.org
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 3865538..3310720 100644 (file)
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -156,8 +156,9 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
                          const struct pwm_state *state)
 {
        struct meson_pwm_channel *channel = &meson->channels[pwm->hwpwm];
-       unsigned int duty, period, pre_div, cnt, duty_cnt;
+       unsigned int pre_div, cnt, duty_cnt;
        unsigned long fin_freq;
+       u64 duty, period;
 
        duty = state->duty_cycle;
        period = state->period;
@@ -179,19 +180,19 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
 
        dev_dbg(meson->chip.dev, "fin_freq: %lu Hz\n", fin_freq);
 
-       pre_div = div64_u64(fin_freq * (u64)period, NSEC_PER_SEC * 0xffffLL);
+       pre_div = div64_u64(fin_freq * period, NSEC_PER_SEC * 0xffffLL);
        if (pre_div > MISC_CLK_DIV_MASK) {
                dev_err(meson->chip.dev, "unable to get period pre_div\n");
                return -EINVAL;
        }
 
-       cnt = div64_u64(fin_freq * (u64)period, NSEC_PER_SEC * (pre_div + 1));
+       cnt = div64_u64(fin_freq * period, NSEC_PER_SEC * (pre_div + 1));
        if (cnt > 0xffff) {
                dev_err(meson->chip.dev, "unable to get period cnt\n");
                return -EINVAL;
        }
 
-       dev_dbg(meson->chip.dev, "period=%u pre_div=%u cnt=%u\n", period,
+       dev_dbg(meson->chip.dev, "period=%llu pre_div=%u cnt=%u\n", period,
                pre_div, cnt);
 
        if (duty == period) {
@@ -204,14 +205,13 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
                channel->lo = cnt;
        } else {
                /* Then check is we can have the duty with the same pre_div */
-               duty_cnt = div64_u64(fin_freq * (u64)duty,
-                                    NSEC_PER_SEC * (pre_div + 1));
+               duty_cnt = div64_u64(fin_freq * duty, NSEC_PER_SEC * (pre_div + 1));
                if (duty_cnt > 0xffff) {
                        dev_err(meson->chip.dev, "unable to get duty cycle\n");
                        return -EINVAL;
                }
 
-               dev_dbg(meson->chip.dev, "duty=%u pre_div=%u duty_cnt=%u\n",
+               dev_dbg(meson->chip.dev, "duty=%llu pre_div=%u duty_cnt=%u\n",
                        duty, pre_div, duty_cnt);
 
                channel->pre_div = pre_div;