[PATCH v5 23/46] pwm: rockchip: add support for atomic update
From: Boris Brezillon <hidden>
Date: 2016-03-30 20:13:41
Also in:
dri-devel, intel-gfx, linux-arm-kernel, linux-clk, linux-fbdev, linux-leds, linux-pwm, linux-rockchip, linux-samsung-soc, lkml
Subsystem:
arm/rockchip soc support, pwm subsystem, the rest · Maintainers:
Heiko Stuebner, Uwe Kleine-König, Linus Torvalds
Implement the ->apply() function to add support for atomic update. Signed-off-by: Boris Brezillon <boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> Tested-by: Heiko Stuebner <redacted> --- drivers/pwm/pwm-rockchip.c | 63 ++++++++++++++++++++++++++++------------------ 1 file changed, 39 insertions(+), 24 deletions(-)
diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index 5c7e79c..ed27740 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c@@ -50,7 +50,8 @@ struct rockchip_pwm_data { const struct pwm_ops *ops; void (*set_enable)(struct pwm_chip *chip, - struct pwm_device *pwm, bool enable); + struct pwm_device *pwm, bool enable, + enum pwm_polarity polarity); void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *pstate); };
@@ -61,7 +62,8 @@ static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c) } static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip, - struct pwm_device *pwm, bool enable) + struct pwm_device *pwm, bool enable, + enum pwm_polarity polarity) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
@@ -91,14 +93,15 @@ static void rockchip_pwm_get_state_v1(struct pwm_chip *chip, } static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, - struct pwm_device *pwm, bool enable) + struct pwm_device *pwm, bool enable, + enum pwm_polarity polarity) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE | PWM_CONTINUOUS; u32 val; - if (pwm_get_polarity(pwm) == PWM_POLARITY_INVERSED) + if (polarity == PWM_POLARITY_INVERSED) enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE; else enable_conf |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
@@ -168,7 +171,6 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); unsigned long period, duty; u64 clk_rate, div; - int ret; clk_rate = clk_get_rate(pc->clk);
@@ -185,15 +187,8 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, do_div(div, pc->data->prescaler * NSEC_PER_SEC); duty = div; - ret = clk_enable(pc->clk); - if (ret) - return ret; - writel(period, pc->base + pc->data->regs.period); writel(duty, pc->base + pc->data->regs.duty); - writel(0, pc->base + pc->data->regs.cntr); - - clk_disable(pc->clk); return 0; }
@@ -211,43 +206,63 @@ static int rockchip_pwm_set_polarity(struct pwm_chip *chip, return 0; } -static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) { struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + struct pwm_state curstate; + bool enabled; int ret; + pwm_get_state(pwm, &curstate); + enabled = curstate.enabled; + ret = clk_enable(pc->clk); if (ret) return ret; - pc->data->set_enable(chip, pwm, true); + if (state->polarity != curstate.polarity && enabled) { + pc->data->set_enable(chip, pwm, false, state->polarity); + enabled = false; + } - return 0; -} + ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period); + if (ret) { + if (enabled != curstate.enabled) + pc->data->set_enable(chip, pwm, !enabled, + state->polarity); -static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); + goto out; + } - pc->data->set_enable(chip, pwm, false); + if (state->enabled != enabled) + pc->data->set_enable(chip, pwm, state->enabled, + state->polarity); + /* + * Update the state with the real hardware, which can differ a bit + * because of period/duty_cycle approximation. + */ + rockchip_pwm_get_state(chip, pwm, state); + +out: clk_disable(pc->clk); + + return ret; } static const struct pwm_ops rockchip_pwm_ops_v1 = { .get_state = rockchip_pwm_get_state, .config = rockchip_pwm_config, - .enable = rockchip_pwm_enable, - .disable = rockchip_pwm_disable, + .apply = rockchip_pwm_apply, .owner = THIS_MODULE, }; static const struct pwm_ops rockchip_pwm_ops_v2 = { .get_state = rockchip_pwm_get_state, .config = rockchip_pwm_config, + .apply = rockchip_pwm_apply, .set_polarity = rockchip_pwm_set_polarity, - .enable = rockchip_pwm_enable, - .disable = rockchip_pwm_disable, .owner = THIS_MODULE, };
--
2.5.0