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pwm: rockchip: Add support for atomic update

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Implement the ->apply() function to add support for atomic update.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Boris Brezillon 2016-06-14 11:13:14 +02:00 committed by Thierry Reding
parent 48cf973cae
commit 2bf1c98aa5
1 changed files with 43 additions and 41 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

84
drivers/pwm/pwm-rockchip.c
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@ -47,10 +47,12 @@ struct rockchip_pwm_regs {
struct rockchip_pwm_data {
struct rockchip_pwm_regs regs;
unsigned int prescaler;
bool supports_polarity;
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 *state);
};
@ -61,7 +63,8 @@ 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 +94,15 @@ 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;
@ -166,7 +170,6 @@ 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);
@ -182,69 +185,66 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
div = clk_rate * duty_ns;
duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);
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;
}
static int rockchip_pwm_set_polarity(struct pwm_chip *chip,
struct pwm_device *pwm,
enum pwm_polarity polarity)
{
/*
* No action needed here because pwm->polarity will be set by the core
* and the core will only change polarity when the PWM is not enabled.
* We'll handle things in set_enable().
*/
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,
.set_polarity = rockchip_pwm_set_polarity,
.enable = rockchip_pwm_enable,
.disable = rockchip_pwm_disable,
.apply = rockchip_pwm_apply,
.owner = THIS_MODULE,
};
@ -269,6 +269,7 @@ static const struct rockchip_pwm_data pwm_data_v2 = {
.ctrl = 0x0c,
},
.prescaler = 1,
.supports_polarity = true,
.ops = &rockchip_pwm_ops_v2,
.set_enable = rockchip_pwm_set_enable_v2,
.get_state = rockchip_pwm_get_state_v2,
@ -282,6 +283,7 @@ static const struct rockchip_pwm_data pwm_data_vop = {
.ctrl = 0x00,
},
.prescaler = 1,
.supports_polarity = true,
.ops = &rockchip_pwm_ops_v2,
.set_enable = rockchip_pwm_set_enable_v2,
.get_state = rockchip_pwm_get_state_v2,
@ -331,7 +333,7 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
pc->chip.base = -1;
pc->chip.npwm = 1;
if (pc->data->ops->set_polarity) {
if (pc->data->supports_polarity) {
pc->chip.of_xlate = of_pwm_xlate_with_flags;
pc->chip.of_pwm_n_cells = 3;
}