diff options
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-imx.c | 43 |
1 files changed, 25 insertions, 18 deletions
diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c index c944f15f574c..d557279446ed 100644 --- a/drivers/pwm/pwm-imx.c +++ b/drivers/pwm/pwm-imx.c @@ -137,18 +137,36 @@ static void imx_pwm_sw_reset(struct pwm_chip *chip) dev_warn(dev, "software reset timeout\n"); } +static void imx_pwm_wait_fifo_slot(struct pwm_chip *chip, + struct pwm_device *pwm) +{ + struct imx_chip *imx = to_imx_chip(chip); + struct device *dev = chip->dev; + unsigned int period_ms; + int fifoav; + u32 sr; + + sr = readl(imx->mmio_base + MX3_PWMSR); + fifoav = sr & MX3_PWMSR_FIFOAV_MASK; + if (fifoav == MX3_PWMSR_FIFOAV_4WORDS) { + period_ms = DIV_ROUND_UP(pwm_get_period(pwm), + NSEC_PER_MSEC); + msleep(period_ms); + + sr = readl(imx->mmio_base + MX3_PWMSR); + if (fifoav == (sr & MX3_PWMSR_FIFOAV_MASK)) + dev_warn(dev, "there is no free FIFO slot\n"); + } +} static int imx_pwm_config_v2(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct imx_chip *imx = to_imx_chip(chip); - struct device *dev = chip->dev; unsigned long long c; unsigned long period_cycles, duty_cycles, prescale; - unsigned int period_ms; bool enable = pwm_is_enabled(pwm); - int fifoav; - u32 cr, sr; + u32 cr; /* * i.MX PWMv2 has a 4-word sample FIFO. @@ -157,21 +175,10 @@ static int imx_pwm_config_v2(struct pwm_chip *chip, * wait for a full PWM cycle to get a relinquished FIFO slot * when the controller is enabled and the FIFO is fully loaded. */ - if (enable) { - sr = readl(imx->mmio_base + MX3_PWMSR); - fifoav = sr & MX3_PWMSR_FIFOAV_MASK; - if (fifoav == MX3_PWMSR_FIFOAV_4WORDS) { - period_ms = DIV_ROUND_UP(pwm_get_period(pwm), - NSEC_PER_MSEC); - msleep(period_ms); - - sr = readl(imx->mmio_base + MX3_PWMSR); - if (fifoav == (sr & MX3_PWMSR_FIFOAV_MASK)) - dev_warn(dev, "there is no free FIFO slot\n"); - } - } else { + if (enable) + imx_pwm_wait_fifo_slot(chip, pwm); + else imx_pwm_sw_reset(chip); - } c = clk_get_rate(imx->clk_per); c = c * period_ns; |