diff options
Diffstat (limited to 'drivers/pwm/pwm-tegra.c')
| -rw-r--r-- | drivers/pwm/pwm-tegra.c | 37 |
1 files changed, 30 insertions, 7 deletions
diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c index e4647840cd6e..8c6ed556db28 100644 --- a/drivers/pwm/pwm-tegra.c +++ b/drivers/pwm/pwm-tegra.c @@ -29,6 +29,7 @@ #include <linux/of_device.h> #include <linux/pwm.h> #include <linux/platform_device.h> +#include <linux/pinctrl/consumer.h> #include <linux/slab.h> #include <linux/reset.h> @@ -49,6 +50,8 @@ struct tegra_pwm_chip { struct clk *clk; struct reset_control*rst; + unsigned long clk_rate; + void __iomem *regs; const struct tegra_pwm_soc *soc; @@ -74,8 +77,8 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct tegra_pwm_chip *pc = to_tegra_pwm_chip(chip); - unsigned long long c = duty_ns; - unsigned long rate, hz; + unsigned long long c = duty_ns, hz; + unsigned long rate; u32 val = 0; int err; @@ -85,8 +88,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * nearest integer during division. */ c *= (1 << PWM_DUTY_WIDTH); - c += period_ns / 2; - do_div(c, period_ns); + c = DIV_ROUND_CLOSEST_ULL(c, period_ns); val = (u32)c << PWM_DUTY_SHIFT; @@ -94,10 +96,11 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * Compute the prescaler value for which (1 << PWM_DUTY_WIDTH) * cycles at the PWM clock rate will take period_ns nanoseconds. */ - rate = clk_get_rate(pc->clk) >> PWM_DUTY_WIDTH; - hz = NSEC_PER_SEC / period_ns; + rate = pc->clk_rate >> PWM_DUTY_WIDTH; - rate = (rate + (hz / 2)) / hz; + /* Consider precision in PWM_SCALE_WIDTH rate calculation */ + hz = DIV_ROUND_CLOSEST_ULL(100ULL * NSEC_PER_SEC, period_ns); + rate = DIV_ROUND_CLOSEST_ULL(100ULL * rate, hz); /* * Since the actual PWM divider is the register's frequency divider @@ -198,6 +201,9 @@ static int tegra_pwm_probe(struct platform_device *pdev) if (IS_ERR(pwm->clk)) return PTR_ERR(pwm->clk); + /* Read PWM clock rate from source */ + pwm->clk_rate = clk_get_rate(pwm->clk); + pwm->rst = devm_reset_control_get(&pdev->dev, "pwm"); if (IS_ERR(pwm->rst)) { ret = PTR_ERR(pwm->rst); @@ -253,6 +259,18 @@ static int tegra_pwm_remove(struct platform_device *pdev) return pwmchip_remove(&pc->chip); } +#ifdef CONFIG_PM_SLEEP +static int tegra_pwm_suspend(struct device *dev) +{ + return pinctrl_pm_select_sleep_state(dev); +} + +static int tegra_pwm_resume(struct device *dev) +{ + return pinctrl_pm_select_default_state(dev); +} +#endif + static const struct tegra_pwm_soc tegra20_pwm_soc = { .num_channels = 4, }; @@ -269,10 +287,15 @@ static const struct of_device_id tegra_pwm_of_match[] = { MODULE_DEVICE_TABLE(of, tegra_pwm_of_match); +static const struct dev_pm_ops tegra_pwm_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(tegra_pwm_suspend, tegra_pwm_resume) +}; + static struct platform_driver tegra_pwm_driver = { .driver = { .name = "tegra-pwm", .of_match_table = tegra_pwm_of_match, + .pm = &tegra_pwm_pm_ops, }, .probe = tegra_pwm_probe, .remove = tegra_pwm_remove, |