diff options
Diffstat (limited to 'drivers/pwm/pwm-rcar.c')
| -rw-r--r-- | drivers/pwm/pwm-rcar.c | 99 |
1 files changed, 48 insertions, 51 deletions
diff --git a/drivers/pwm/pwm-rcar.c b/drivers/pwm/pwm-rcar.c index a41812fc6f95..cfe7dd1b448e 100644 --- a/drivers/pwm/pwm-rcar.c +++ b/drivers/pwm/pwm-rcar.c @@ -8,6 +8,8 @@ #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> +#include <linux/log2.h> +#include <linux/math64.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> @@ -68,19 +70,15 @@ static void rcar_pwm_update(struct rcar_pwm_chip *rp, u32 mask, u32 data, static int rcar_pwm_get_clock_division(struct rcar_pwm_chip *rp, int period_ns) { unsigned long clk_rate = clk_get_rate(rp->clk); - unsigned long long max; /* max cycle / nanoseconds */ - unsigned int div; + u64 div, tmp; if (clk_rate == 0) return -EINVAL; - for (div = 0; div <= RCAR_PWM_MAX_DIVISION; div++) { - max = (unsigned long long)NSEC_PER_SEC * RCAR_PWM_MAX_CYCLE * - (1 << div); - do_div(max, clk_rate); - if (period_ns <= max) - break; - } + div = (u64)NSEC_PER_SEC * RCAR_PWM_MAX_CYCLE; + tmp = (u64)period_ns * clk_rate + div - 1; + tmp = div64_u64(tmp, div); + div = ilog2(tmp - 1) + 1; return (div <= RCAR_PWM_MAX_DIVISION) ? div : -ERANGE; } @@ -139,39 +137,8 @@ static void rcar_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) pm_runtime_put(chip->dev); } -static int rcar_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, - int duty_ns, int period_ns) +static int rcar_pwm_enable(struct rcar_pwm_chip *rp) { - struct rcar_pwm_chip *rp = to_rcar_pwm_chip(chip); - int div, ret; - - div = rcar_pwm_get_clock_division(rp, period_ns); - if (div < 0) - return div; - - /* - * Let the core driver set pwm->period if disabled and duty_ns == 0. - * But, this driver should prevent to set the new duty_ns if current - * duty_cycle is not set - */ - if (!pwm_is_enabled(pwm) && !duty_ns && !pwm->state.duty_cycle) - return 0; - - rcar_pwm_update(rp, RCAR_PWMCR_SYNC, RCAR_PWMCR_SYNC, RCAR_PWMCR); - - ret = rcar_pwm_set_counter(rp, div, duty_ns, period_ns); - if (!ret) - rcar_pwm_set_clock_control(rp, div); - - /* The SYNC should be set to 0 even if rcar_pwm_set_counter failed */ - rcar_pwm_update(rp, RCAR_PWMCR_SYNC, 0, RCAR_PWMCR); - - return ret; -} - -static int rcar_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct rcar_pwm_chip *rp = to_rcar_pwm_chip(chip); u32 value; /* Don't enable the PWM device if CYC0 or PH0 is 0 */ @@ -185,19 +152,51 @@ static int rcar_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) return 0; } -static void rcar_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +static void rcar_pwm_disable(struct rcar_pwm_chip *rp) +{ + rcar_pwm_update(rp, RCAR_PWMCR_EN0, 0, RCAR_PWMCR); +} + +static int rcar_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) { struct rcar_pwm_chip *rp = to_rcar_pwm_chip(chip); + struct pwm_state cur_state; + int div, ret; - rcar_pwm_update(rp, RCAR_PWMCR_EN0, 0, RCAR_PWMCR); + /* This HW/driver only supports normal polarity */ + pwm_get_state(pwm, &cur_state); + if (state->polarity != PWM_POLARITY_NORMAL) + return -ENOTSUPP; + + if (!state->enabled) { + rcar_pwm_disable(rp); + return 0; + } + + div = rcar_pwm_get_clock_division(rp, state->period); + if (div < 0) + return div; + + rcar_pwm_update(rp, RCAR_PWMCR_SYNC, RCAR_PWMCR_SYNC, RCAR_PWMCR); + + ret = rcar_pwm_set_counter(rp, div, state->duty_cycle, state->period); + if (!ret) + rcar_pwm_set_clock_control(rp, div); + + /* The SYNC should be set to 0 even if rcar_pwm_set_counter failed */ + rcar_pwm_update(rp, RCAR_PWMCR_SYNC, 0, RCAR_PWMCR); + + if (!ret && state->enabled) + ret = rcar_pwm_enable(rp); + + return ret; } static const struct pwm_ops rcar_pwm_ops = { .request = rcar_pwm_request, .free = rcar_pwm_free, - .config = rcar_pwm_config, - .enable = rcar_pwm_enable, - .disable = rcar_pwm_disable, + .apply = rcar_pwm_apply, .owner = THIS_MODULE, }; @@ -279,18 +278,16 @@ static int rcar_pwm_suspend(struct device *dev) static int rcar_pwm_resume(struct device *dev) { struct pwm_device *pwm = rcar_pwm_dev_to_pwm_dev(dev); + struct pwm_state state; if (!test_bit(PWMF_REQUESTED, &pwm->flags)) return 0; pm_runtime_get_sync(dev); - rcar_pwm_config(pwm->chip, pwm, pwm->state.duty_cycle, - pwm->state.period); - if (pwm_is_enabled(pwm)) - rcar_pwm_enable(pwm->chip, pwm); + pwm_get_state(pwm, &state); - return 0; + return rcar_pwm_apply(pwm->chip, pwm, &state); } #endif /* CONFIG_PM_SLEEP */ static SIMPLE_DEV_PM_OPS(rcar_pwm_pm_ops, rcar_pwm_suspend, rcar_pwm_resume); |