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path: root/drivers/pwm/pwm-ep93xx.c
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Diffstat (limited to 'drivers/pwm/pwm-ep93xx.c')
-rw-r--r--drivers/pwm/pwm-ep93xx.c158
1 files changed, 65 insertions, 93 deletions
diff --git a/drivers/pwm/pwm-ep93xx.c b/drivers/pwm/pwm-ep93xx.c
index 4bab73073ad7..994f89ac43b4 100644
--- a/drivers/pwm/pwm-ep93xx.c
+++ b/drivers/pwm/pwm-ep93xx.c
@@ -17,6 +17,7 @@
*/
#include <linux/module.h>
+#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/clk.h>
@@ -26,8 +27,6 @@
#include <asm/div64.h>
-#include <linux/soc/cirrus/ep93xx.h> /* for ep93xx_pwm_{acquire,release}_gpio() */
-
#define EP93XX_PWMx_TERM_COUNT 0x00
#define EP93XX_PWMx_DUTY_CYCLE 0x04
#define EP93XX_PWMx_ENABLE 0x08
@@ -36,57 +35,75 @@
struct ep93xx_pwm {
void __iomem *base;
struct clk *clk;
- struct pwm_chip chip;
};
static inline struct ep93xx_pwm *to_ep93xx_pwm(struct pwm_chip *chip)
{
- return container_of(chip, struct ep93xx_pwm, chip);
-}
-
-static int ep93xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct platform_device *pdev = to_platform_device(chip->dev);
-
- return ep93xx_pwm_acquire_gpio(pdev);
-}
-
-static void ep93xx_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct platform_device *pdev = to_platform_device(chip->dev);
-
- ep93xx_pwm_release_gpio(pdev);
+ return pwmchip_get_drvdata(chip);
}
-static int ep93xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns)
+static int ep93xx_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
{
+ int ret;
struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip);
+ bool enabled = state->enabled;
void __iomem *base = ep93xx_pwm->base;
unsigned long long c;
unsigned long period_cycles;
unsigned long duty_cycles;
unsigned long term;
- int ret = 0;
+
+ if (state->polarity != pwm->state.polarity) {
+ if (enabled) {
+ writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_ENABLE);
+ clk_disable_unprepare(ep93xx_pwm->clk);
+ enabled = false;
+ }
+
+ /*
+ * The clock needs to be enabled to access the PWM registers.
+ * Polarity can only be changed when the PWM is disabled.
+ */
+ ret = clk_prepare_enable(ep93xx_pwm->clk);
+ if (ret)
+ return ret;
+
+ if (state->polarity == PWM_POLARITY_INVERSED)
+ writew(0x1, ep93xx_pwm->base + EP93XX_PWMx_INVERT);
+ else
+ writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_INVERT);
+
+ clk_disable_unprepare(ep93xx_pwm->clk);
+ }
+
+ if (!state->enabled) {
+ if (enabled) {
+ writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_ENABLE);
+ clk_disable_unprepare(ep93xx_pwm->clk);
+ }
+
+ return 0;
+ }
/*
* The clock needs to be enabled to access the PWM registers.
* Configuration can be changed at any time.
*/
if (!pwm_is_enabled(pwm)) {
- ret = clk_enable(ep93xx_pwm->clk);
+ ret = clk_prepare_enable(ep93xx_pwm->clk);
if (ret)
return ret;
}
c = clk_get_rate(ep93xx_pwm->clk);
- c *= period_ns;
+ c *= state->period;
do_div(c, 1000000000);
period_cycles = c;
c = period_cycles;
- c *= duty_ns;
- do_div(c, period_ns);
+ c *= state->duty_cycle;
+ do_div(c, state->period);
duty_cycles = c;
if (period_cycles < 0x10000 && duty_cycles < 0x10000) {
@@ -100,84 +117,44 @@ static int ep93xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
writew(duty_cycles, base + EP93XX_PWMx_DUTY_CYCLE);
writew(period_cycles, base + EP93XX_PWMx_TERM_COUNT);
}
+ ret = 0;
} else {
ret = -EINVAL;
}
if (!pwm_is_enabled(pwm))
- clk_disable(ep93xx_pwm->clk);
-
- return ret;
-}
-
-static int ep93xx_pwm_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
- enum pwm_polarity polarity)
-{
- struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip);
- int ret;
+ clk_disable_unprepare(ep93xx_pwm->clk);
- /*
- * The clock needs to be enabled to access the PWM registers.
- * Polarity can only be changed when the PWM is disabled.
- */
- ret = clk_enable(ep93xx_pwm->clk);
if (ret)
return ret;
- if (polarity == PWM_POLARITY_INVERSED)
- writew(0x1, ep93xx_pwm->base + EP93XX_PWMx_INVERT);
- else
- writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_INVERT);
-
- clk_disable(ep93xx_pwm->clk);
-
- return 0;
-}
-
-static int ep93xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip);
- int ret;
-
- ret = clk_enable(ep93xx_pwm->clk);
- if (ret)
- return ret;
+ if (!enabled) {
+ ret = clk_prepare_enable(ep93xx_pwm->clk);
+ if (ret)
+ return ret;
- writew(0x1, ep93xx_pwm->base + EP93XX_PWMx_ENABLE);
+ writew(0x1, ep93xx_pwm->base + EP93XX_PWMx_ENABLE);
+ }
return 0;
}
-static void ep93xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct ep93xx_pwm *ep93xx_pwm = to_ep93xx_pwm(chip);
-
- writew(0x0, ep93xx_pwm->base + EP93XX_PWMx_ENABLE);
- clk_disable(ep93xx_pwm->clk);
-}
-
static const struct pwm_ops ep93xx_pwm_ops = {
- .request = ep93xx_pwm_request,
- .free = ep93xx_pwm_free,
- .config = ep93xx_pwm_config,
- .set_polarity = ep93xx_pwm_polarity,
- .enable = ep93xx_pwm_enable,
- .disable = ep93xx_pwm_disable,
- .owner = THIS_MODULE,
+ .apply = ep93xx_pwm_apply,
};
static int ep93xx_pwm_probe(struct platform_device *pdev)
{
+ struct pwm_chip *chip;
struct ep93xx_pwm *ep93xx_pwm;
- struct resource *res;
int ret;
- ep93xx_pwm = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_pwm), GFP_KERNEL);
- if (!ep93xx_pwm)
- return -ENOMEM;
+ chip = devm_pwmchip_alloc(&pdev->dev, 1, sizeof(*ep93xx_pwm));
+ if (IS_ERR(chip))
+ return PTR_ERR(chip);
+ ep93xx_pwm = to_ep93xx_pwm(chip);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- ep93xx_pwm->base = devm_ioremap_resource(&pdev->dev, res);
+ ep93xx_pwm->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(ep93xx_pwm->base))
return PTR_ERR(ep93xx_pwm->base);
@@ -185,32 +162,27 @@ static int ep93xx_pwm_probe(struct platform_device *pdev)
if (IS_ERR(ep93xx_pwm->clk))
return PTR_ERR(ep93xx_pwm->clk);
- ep93xx_pwm->chip.dev = &pdev->dev;
- ep93xx_pwm->chip.ops = &ep93xx_pwm_ops;
- ep93xx_pwm->chip.base = -1;
- ep93xx_pwm->chip.npwm = 1;
+ chip->ops = &ep93xx_pwm_ops;
- ret = pwmchip_add(&ep93xx_pwm->chip);
+ ret = devm_pwmchip_add(&pdev->dev, chip);
if (ret < 0)
return ret;
- platform_set_drvdata(pdev, ep93xx_pwm);
return 0;
}
-static int ep93xx_pwm_remove(struct platform_device *pdev)
-{
- struct ep93xx_pwm *ep93xx_pwm = platform_get_drvdata(pdev);
-
- return pwmchip_remove(&ep93xx_pwm->chip);
-}
+static const struct of_device_id ep93xx_pwm_of_ids[] = {
+ { .compatible = "cirrus,ep9301-pwm" },
+ { /* sentinel */}
+};
+MODULE_DEVICE_TABLE(of, ep93xx_pwm_of_ids);
static struct platform_driver ep93xx_pwm_driver = {
.driver = {
.name = "ep93xx-pwm",
+ .of_match_table = ep93xx_pwm_of_ids,
},
.probe = ep93xx_pwm_probe,
- .remove = ep93xx_pwm_remove,
};
module_platform_driver(ep93xx_pwm_driver);