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pwm: tiecap: Implement .apply() callback

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To eventually get rid of all legacy drivers convert this driver to the
modern world implementing .apply(). This just pushes down a slightly
optimized variant of how legacy drivers are handled in the core.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Uwe Kleine-König 2021-05-01 18:01:39 +02:00 committed by Thierry Reding
parent ec67fba92e
commit 0ca7acd847
1 changed files with 45 additions and 10 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

55
drivers/pwm/pwm-tiecap.c
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@ -48,16 +48,13 @@ static inline struct ecap_pwm_chip *to_ecap_pwm_chip(struct pwm_chip *chip)
* duty_ns = 10^9 * duty_cycles / PWM_CLK_RATE * duty_ns = 10^9 * duty_cycles / PWM_CLK_RATE
*/ */
static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns) int duty_ns, int period_ns, int enabled)
{ {
struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip); struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
u32 period_cycles, duty_cycles; u32 period_cycles, duty_cycles;
unsigned long long c; unsigned long long c;
u16 value; u16 value;
if (period_ns > NSEC_PER_SEC)
return -ERANGE;
c = pc->clk_rate; c = pc->clk_rate;
c = c * period_ns; c = c * period_ns;
do_div(c, NSEC_PER_SEC); do_div(c, NSEC_PER_SEC);
@ -82,7 +79,7 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
writew(value, pc->mmio_base + ECCTL2); writew(value, pc->mmio_base + ECCTL2);
if (!pwm_is_enabled(pwm)) { if (!enabled) {
/* Update active registers if not running */ /* Update active registers if not running */
writel(duty_cycles, pc->mmio_base + CAP2); writel(duty_cycles, pc->mmio_base + CAP2);
writel(period_cycles, pc->mmio_base + CAP1); writel(period_cycles, pc->mmio_base + CAP1);
@ -96,7 +93,7 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
writel(period_cycles, pc->mmio_base + CAP3); writel(period_cycles, pc->mmio_base + CAP3);
} }
if (!pwm_is_enabled(pwm)) { if (!enabled) {
value = readw(pc->mmio_base + ECCTL2); value = readw(pc->mmio_base + ECCTL2);
/* Disable APWM mode to put APWM output Low */ /* Disable APWM mode to put APWM output Low */
value &= ~ECCTL2_APWM_MODE; value &= ~ECCTL2_APWM_MODE;
@ -168,11 +165,49 @@ static void ecap_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
pm_runtime_put_sync(pc->chip.dev); pm_runtime_put_sync(pc->chip.dev);
} }
static int ecap_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
const struct pwm_state *state)
{
int err;
int enabled = pwm->state.enabled;
if (state->polarity != pwm->state.polarity) {
if (enabled) {
ecap_pwm_disable(chip, pwm);
enabled = false;
}
err = ecap_pwm_set_polarity(chip, pwm, state->polarity);
if (err)
return err;
}
if (!state->enabled) {
if (enabled)
ecap_pwm_disable(chip, pwm);
return 0;
}
if (state->period != pwm->state.period ||
state->duty_cycle != pwm->state.duty_cycle) {
if (state->period > NSEC_PER_SEC)
return -ERANGE;
err = ecap_pwm_config(chip, pwm, state->duty_cycle,
state->period, enabled);
if (err)
return err;
}
if (!enabled)
return ecap_pwm_enable(chip, pwm);
return 0;
}
static const struct pwm_ops ecap_pwm_ops = { static const struct pwm_ops ecap_pwm_ops = {
.config = ecap_pwm_config, .apply = ecap_pwm_apply,
.set_polarity = ecap_pwm_set_polarity,
.enable = ecap_pwm_enable,
.disable = ecap_pwm_disable,
.owner = THIS_MODULE, .owner = THIS_MODULE,
}; };