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path: root/drivers/pwm/pwm-tiehrpwm.c
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Diffstat (limited to 'drivers/pwm/pwm-tiehrpwm.c')
-rw-r--r--drivers/pwm/pwm-tiehrpwm.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index c3756d1..b1996bc 100644
--- a/drivers/pwm/pwm-tiehrpwm.c
+++ b/drivers/pwm/pwm-tiehrpwm.c
@@ -104,6 +104,7 @@ struct ehrpwm_pwm_chip {
struct pwm_chip chip;
unsigned int clk_rate;
void __iomem *mmio_base;
+ unsigned long period_cycles[NUM_PWM_CHANNEL];
};
static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
@@ -210,6 +211,7 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long long c;
unsigned long period_cycles, duty_cycles;
unsigned short ps_divval, tb_divval;
+ int i;
if (period_ns < 0 || duty_ns < 0 || period_ns > NSEC_PER_SEC)
return -ERANGE;
@@ -229,6 +231,28 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
duty_cycles = (unsigned long)c;
}
+ /*
+ * Period values should be same for multiple PWM channels as IP uses
+ * same period register for multiple channels.
+ */
+ for (i = 0; i < NUM_PWM_CHANNEL; i++) {
+ if (pc->period_cycles[i] &&
+ (pc->period_cycles[i] != period_cycles)) {
+ /*
+ * Allow channel to reconfigure period if no other
+ * channels being configured.
+ */
+ if (i == pwm->hwpwm)
+ continue;
+
+ dev_err(chip->dev, "Period value conflicts with channel %d\n",
+ i);
+ return -EINVAL;
+ }
+ }
+
+ pc->period_cycles[pwm->hwpwm] = period_cycles;
+
/* Configure clock prescaler to support Low frequency PWM wave */
if (set_prescale_div(period_cycles/PERIOD_MAX, &ps_divval,
&tb_divval)) {
@@ -320,10 +344,15 @@ static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
+ struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+
if (test_bit(PWMF_ENABLED, &pwm->flags)) {
dev_warn(chip->dev, "Removing PWM device without disabling\n");
pm_runtime_put_sync(chip->dev);
}
+
+ /* set period value to zero on free */
+ pc->period_cycles[pwm->hwpwm] = 0;
}
static const struct pwm_ops ehrpwm_pwm_ops = {
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