summaryrefslogtreecommitdiff
path: root/drivers/pwm/pwm-atmel-hlcdc.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-09 15:34:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-09 15:34:20 -0700
commitecc721a72c121e8b641d68efd24a225abedb9a30 (patch)
tree15d514f0c374292218a52dcc24a82d7c55bcfcfc /drivers/pwm/pwm-atmel-hlcdc.c
parent28b47809b2171a6cfbab839936b24280639c9f85 (diff)
parent97512ceafaacf8cdb96d6a36ae55e8335c0a9e55 (diff)
Merge tag 'pwm/for-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding: "Adds a new driver for the PWM controller found on MediaTek SoCs and extends support for the Atmel PWM controller to include the SAMA5D2. Some existing drivers have been migrated to the atomic API and a few others see miscellaneous improvements" * tag 'pwm/for-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: pwm: tegra: Read PWM clock source rate in driver init pwm: pca9685: Fix GPIO-only operation pwm: mediatek: Don't explicitly set .owner pwm: tegra: Avoid potential overflow for short periods pwm: tegra: Add support to configure pin state in suspends/resume pwm: tegra: Add DT binding details to configure pin in suspends/resume pwm: tegra: Increase precision in PWM rate calculation pwm: tegra: Use DIV_ROUND_CLOSEST_ULL() instead of local implementation pwm: Add MediaTek PWM support dt-bindings: pwm: Add MediaTek PWM bindings pwm: atmel: Enable PWM on sama5d2 pwm: atmel: Switch to atomic PWM pwm: atmel-hlcdc: Implement the suspend/resume hooks pwm: atmel-hlcdc: Convert to the atomic PWM API
Diffstat (limited to 'drivers/pwm/pwm-atmel-hlcdc.c')
-rw-r--r--drivers/pwm/pwm-atmel-hlcdc.c260
1 files changed, 135 insertions, 125 deletions
diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
index 999187277ea5..54c6633d9b5d 100644
--- a/drivers/pwm/pwm-atmel-hlcdc.c
+++ b/drivers/pwm/pwm-atmel-hlcdc.c
@@ -49,172 +49,181 @@ static inline struct atmel_hlcdc_pwm *to_atmel_hlcdc_pwm(struct pwm_chip *chip)
return container_of(chip, struct atmel_hlcdc_pwm, chip);
}
-static int atmel_hlcdc_pwm_config(struct pwm_chip *c,
- struct pwm_device *pwm,
- int duty_ns, int period_ns)
+static int atmel_hlcdc_pwm_apply(struct pwm_chip *c, struct pwm_device *pwm,
+ struct pwm_state *state)
{
struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
struct atmel_hlcdc *hlcdc = chip->hlcdc;
- struct clk *new_clk = hlcdc->slow_clk;
- u64 pwmcval = duty_ns * 256;
- unsigned long clk_freq;
- u64 clk_period_ns;
- u32 pwmcfg;
- int pres;
-
- if (!chip->errata || !chip->errata->slow_clk_erratum) {
- clk_freq = clk_get_rate(new_clk);
- if (!clk_freq)
- return -EINVAL;
+ unsigned int status;
+ int ret;
- clk_period_ns = (u64)NSEC_PER_SEC * 256;
- do_div(clk_period_ns, clk_freq);
- }
+ if (state->enabled) {
+ struct clk *new_clk = hlcdc->slow_clk;
+ u64 pwmcval = state->duty_cycle * 256;
+ unsigned long clk_freq;
+ u64 clk_period_ns;
+ u32 pwmcfg;
+ int pres;
+
+ if (!chip->errata || !chip->errata->slow_clk_erratum) {
+ clk_freq = clk_get_rate(new_clk);
+ if (!clk_freq)
+ return -EINVAL;
+
+ clk_period_ns = (u64)NSEC_PER_SEC * 256;
+ do_div(clk_period_ns, clk_freq);
+ }
+
+ /* Errata: cannot use slow clk on some IP revisions */
+ if ((chip->errata && chip->errata->slow_clk_erratum) ||
+ clk_period_ns > state->period) {
+ new_clk = hlcdc->sys_clk;
+ clk_freq = clk_get_rate(new_clk);
+ if (!clk_freq)
+ return -EINVAL;
+
+ clk_period_ns = (u64)NSEC_PER_SEC * 256;
+ do_div(clk_period_ns, clk_freq);
+ }
+
+ for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) {
+ /* Errata: cannot divide by 1 on some IP revisions */
+ if (!pres && chip->errata &&
+ chip->errata->div1_clk_erratum)
+ continue;
+
+ if ((clk_period_ns << pres) >= state->period)
+ break;
+ }
- /* Errata: cannot use slow clk on some IP revisions */
- if ((chip->errata && chip->errata->slow_clk_erratum) ||
- clk_period_ns > period_ns) {
- new_clk = hlcdc->sys_clk;
- clk_freq = clk_get_rate(new_clk);
- if (!clk_freq)
+ if (pres > ATMEL_HLCDC_PWMPS_MAX)
return -EINVAL;
- clk_period_ns = (u64)NSEC_PER_SEC * 256;
- do_div(clk_period_ns, clk_freq);
- }
+ pwmcfg = ATMEL_HLCDC_PWMPS(pres);
- for (pres = 0; pres <= ATMEL_HLCDC_PWMPS_MAX; pres++) {
- /* Errata: cannot divide by 1 on some IP revisions */
- if (!pres && chip->errata && chip->errata->div1_clk_erratum)
- continue;
+ if (new_clk != chip->cur_clk) {
+ u32 gencfg = 0;
+ int ret;
- if ((clk_period_ns << pres) >= period_ns)
- break;
- }
+ ret = clk_prepare_enable(new_clk);
+ if (ret)
+ return ret;
- if (pres > ATMEL_HLCDC_PWMPS_MAX)
- return -EINVAL;
+ clk_disable_unprepare(chip->cur_clk);
+ chip->cur_clk = new_clk;
- pwmcfg = ATMEL_HLCDC_PWMPS(pres);
+ if (new_clk == hlcdc->sys_clk)
+ gencfg = ATMEL_HLCDC_CLKPWMSEL;
- if (new_clk != chip->cur_clk) {
- u32 gencfg = 0;
- int ret;
+ ret = regmap_update_bits(hlcdc->regmap,
+ ATMEL_HLCDC_CFG(0),
+ ATMEL_HLCDC_CLKPWMSEL,
+ gencfg);
+ if (ret)
+ return ret;
+ }
- ret = clk_prepare_enable(new_clk);
- if (ret)
- return ret;
+ do_div(pwmcval, state->period);
- clk_disable_unprepare(chip->cur_clk);
- chip->cur_clk = new_clk;
+ /*
+ * The PWM duty cycle is configurable from 0/256 to 255/256 of
+ * the period cycle. Hence we can't set a duty cycle occupying
+ * the whole period cycle if we're asked to.
+ * Set it to 255 if pwmcval is greater than 256.
+ */
+ if (pwmcval > 255)
+ pwmcval = 255;
- if (new_clk == hlcdc->sys_clk)
- gencfg = ATMEL_HLCDC_CLKPWMSEL;
+ pwmcfg |= ATMEL_HLCDC_PWMCVAL(pwmcval);
- ret = regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(0),
- ATMEL_HLCDC_CLKPWMSEL, gencfg);
+ if (state->polarity == PWM_POLARITY_NORMAL)
+ pwmcfg |= ATMEL_HLCDC_PWMPOL;
+
+ ret = regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
+ ATMEL_HLCDC_PWMCVAL_MASK |
+ ATMEL_HLCDC_PWMPS_MASK |
+ ATMEL_HLCDC_PWMPOL,
+ pwmcfg);
if (ret)
return ret;
- }
- do_div(pwmcval, period_ns);
-
- /*
- * The PWM duty cycle is configurable from 0/256 to 255/256 of the
- * period cycle. Hence we can't set a duty cycle occupying the
- * whole period cycle if we're asked to.
- * Set it to 255 if pwmcval is greater than 256.
- */
- if (pwmcval > 255)
- pwmcval = 255;
-
- pwmcfg |= ATMEL_HLCDC_PWMCVAL(pwmcval);
+ ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_EN,
+ ATMEL_HLCDC_PWM);
+ if (ret)
+ return ret;
- return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
- ATMEL_HLCDC_PWMCVAL_MASK |
- ATMEL_HLCDC_PWMPS_MASK,
- pwmcfg);
-}
+ ret = regmap_read_poll_timeout(hlcdc->regmap, ATMEL_HLCDC_SR,
+ status,
+ status & ATMEL_HLCDC_PWM,
+ 10, 0);
+ if (ret)
+ return ret;
+ } else {
+ ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_DIS,
+ ATMEL_HLCDC_PWM);
+ if (ret)
+ return ret;
-static int atmel_hlcdc_pwm_set_polarity(struct pwm_chip *c,
- struct pwm_device *pwm,
- enum pwm_polarity polarity)
-{
- struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
- struct atmel_hlcdc *hlcdc = chip->hlcdc;
- u32 cfg = 0;
+ ret = regmap_read_poll_timeout(hlcdc->regmap, ATMEL_HLCDC_SR,
+ status,
+ !(status & ATMEL_HLCDC_PWM),
+ 10, 0);
+ if (ret)
+ return ret;
- if (polarity == PWM_POLARITY_NORMAL)
- cfg = ATMEL_HLCDC_PWMPOL;
+ clk_disable_unprepare(chip->cur_clk);
+ chip->cur_clk = NULL;
+ }
- return regmap_update_bits(hlcdc->regmap, ATMEL_HLCDC_CFG(6),
- ATMEL_HLCDC_PWMPOL, cfg);
+ return 0;
}
-static int atmel_hlcdc_pwm_enable(struct pwm_chip *c, struct pwm_device *pwm)
-{
- struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
- struct atmel_hlcdc *hlcdc = chip->hlcdc;
- u32 status;
- int ret;
+static const struct pwm_ops atmel_hlcdc_pwm_ops = {
+ .apply = atmel_hlcdc_pwm_apply,
+ .owner = THIS_MODULE,
+};
- ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_EN, ATMEL_HLCDC_PWM);
- if (ret)
- return ret;
+static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_at91sam9x5_errata = {
+ .slow_clk_erratum = true,
+};
- while (true) {
- ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status);
- if (ret)
- return ret;
+static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_sama5d3_errata = {
+ .div1_clk_erratum = true,
+};
- if ((status & ATMEL_HLCDC_PWM) != 0)
- break;
+#ifdef CONFIG_PM_SLEEP
+static int atmel_hlcdc_pwm_suspend(struct device *dev)
+{
+ struct atmel_hlcdc_pwm *chip = dev_get_drvdata(dev);
- usleep_range(1, 10);
- }
+ /* Keep the periph clock enabled if the PWM is still running. */
+ if (pwm_is_enabled(&chip->chip.pwms[0]))
+ clk_disable_unprepare(chip->hlcdc->periph_clk);
return 0;
}
-static void atmel_hlcdc_pwm_disable(struct pwm_chip *c,
- struct pwm_device *pwm)
+static int atmel_hlcdc_pwm_resume(struct device *dev)
{
- struct atmel_hlcdc_pwm *chip = to_atmel_hlcdc_pwm(c);
- struct atmel_hlcdc *hlcdc = chip->hlcdc;
- u32 status;
+ struct atmel_hlcdc_pwm *chip = dev_get_drvdata(dev);
+ struct pwm_state state;
int ret;
- ret = regmap_write(hlcdc->regmap, ATMEL_HLCDC_DIS, ATMEL_HLCDC_PWM);
- if (ret)
- return;
+ pwm_get_state(&chip->chip.pwms[0], &state);
- while (true) {
- ret = regmap_read(hlcdc->regmap, ATMEL_HLCDC_SR, &status);
+ /* Re-enable the periph clock it was stopped during suspend. */
+ if (!state.enabled) {
+ ret = clk_prepare_enable(chip->hlcdc->periph_clk);
if (ret)
- return;
-
- if ((status & ATMEL_HLCDC_PWM) == 0)
- break;
-
- usleep_range(1, 10);
+ return ret;
}
-}
-
-static const struct pwm_ops atmel_hlcdc_pwm_ops = {
- .config = atmel_hlcdc_pwm_config,
- .set_polarity = atmel_hlcdc_pwm_set_polarity,
- .enable = atmel_hlcdc_pwm_enable,
- .disable = atmel_hlcdc_pwm_disable,
- .owner = THIS_MODULE,
-};
-static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_at91sam9x5_errata = {
- .slow_clk_erratum = true,
-};
+ return atmel_hlcdc_pwm_apply(&chip->chip, &chip->chip.pwms[0], &state);
+}
+#endif
-static const struct atmel_hlcdc_pwm_errata atmel_hlcdc_pwm_sama5d3_errata = {
- .div1_clk_erratum = true,
-};
+static SIMPLE_DEV_PM_OPS(atmel_hlcdc_pwm_pm_ops,
+ atmel_hlcdc_pwm_suspend, atmel_hlcdc_pwm_resume);
static const struct of_device_id atmel_hlcdc_dt_ids[] = {
{
@@ -305,6 +314,7 @@ static struct platform_driver atmel_hlcdc_pwm_driver = {
.driver = {
.name = "atmel-hlcdc-pwm",
.of_match_table = atmel_hlcdc_pwm_dt_ids,
+ .pm = &atmel_hlcdc_pwm_pm_ops,
},
.probe = atmel_hlcdc_pwm_probe,
.remove = atmel_hlcdc_pwm_remove,