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authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2022-04-08 17:22:39 +0200
committerThierry Reding <thierry.reding@gmail.com>2022-04-22 18:43:09 +0200
commit1d24cc89203081919e339b734728149642786f51 (patch)
tree45d5161c438c9e07de7a295a2f201c65e3ce1a81 /drivers/pwm
parentpwm: lp3943: Fix duty calculation in case period was clamped (diff)
downloadlinux-dev-1d24cc89203081919e339b734728149642786f51.tar.xz
linux-dev-1d24cc89203081919e339b734728149642786f51.zip
pwm: lp3943: Implement .apply() callback
To eventually get rid of all legacy drivers convert this driver to the modern world implementing .apply(). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-lp3943.c41
1 files changed, 34 insertions, 7 deletions
diff --git a/drivers/pwm/pwm-lp3943.c b/drivers/pwm/pwm-lp3943.c
index 2bd04ecb508c..215ef9069114 100644
--- a/drivers/pwm/pwm-lp3943.c
+++ b/drivers/pwm/pwm-lp3943.c
@@ -93,7 +93,7 @@ static void lp3943_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
}
static int lp3943_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns)
+ u64 duty_ns, u64 period_ns)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943 *lp3943 = lp3943_pwm->lp3943;
@@ -118,15 +118,20 @@ static int lp3943_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
reg_duty = LP3943_REG_PWM1;
}
- period_ns = clamp(period_ns, LP3943_MIN_PERIOD, LP3943_MAX_PERIOD);
- val = (u8)(period_ns / LP3943_MIN_PERIOD - 1);
+ /*
+ * Note that after this clamping, period_ns fits into an int. This is
+ * helpful because we can resort to integer division below instead of
+ * the (more expensive) 64 bit division.
+ */
+ period_ns = clamp(period_ns, (u64)LP3943_MIN_PERIOD, (u64)LP3943_MAX_PERIOD);
+ val = (u8)((int)period_ns / LP3943_MIN_PERIOD - 1);
err = lp3943_write_byte(lp3943, reg_prescale, val);
if (err)
return err;
duty_ns = min(duty_ns, period_ns);
- val = (u8)(duty_ns * LP3943_MAX_DUTY / period_ns);
+ val = (u8)((int)duty_ns * LP3943_MAX_DUTY / (int)period_ns);
return lp3943_write_byte(lp3943, reg_duty, val);
}
@@ -183,12 +188,34 @@ static void lp3943_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
lp3943_pwm_set_mode(lp3943_pwm, pwm_map, LP3943_GPIO_OUT_HIGH);
}
+static int lp3943_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ int err;
+
+ if (state->polarity != PWM_POLARITY_NORMAL)
+ return -EINVAL;
+
+ if (!state->enabled) {
+ if (pwm->state.enabled)
+ lp3943_pwm_disable(chip, pwm);
+ return 0;
+ }
+
+ err = lp3943_pwm_config(chip, pwm, state->duty_cycle, state->period);
+ if (err)
+ return err;
+
+ if (!pwm->state.enabled)
+ err = lp3943_pwm_enable(chip, pwm);
+
+ return err;
+}
+
static const struct pwm_ops lp3943_pwm_ops = {
.request = lp3943_pwm_request,
.free = lp3943_pwm_free,
- .config = lp3943_pwm_config,
- .enable = lp3943_pwm_enable,
- .disable = lp3943_pwm_disable,
+ .apply = lp3943_pwm_apply,
.owner = THIS_MODULE,
};