1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index c3756d1be194..b1996bcd5b78 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 = {