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-rw-r--r--drivers/pwm/Kconfig4
-rw-r--r--drivers/pwm/core.c9
-rw-r--r--drivers/pwm/pwm-atmel.c1
-rw-r--r--drivers/pwm/pwm-samsung.c30
-rw-r--r--drivers/pwm/pwm-visconti.c14
-rw-r--r--drivers/pwm/pwm-vt8500.c16
6 files changed, 43 insertions, 31 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index aa29841bbb79..21e3b05a5153 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -476,7 +476,9 @@ config PWM_SAMSUNG
depends on PLAT_SAMSUNG || ARCH_S5PV210 || ARCH_EXYNOS || COMPILE_TEST
depends on HAS_IOMEM
help
- Generic PWM framework driver for Samsung.
+ Generic PWM framework driver for Samsung S3C24xx, S3C64xx, S5Pv210
+ and Exynos SoCs.
+ Choose Y here only if you build for such Samsung SoC.
To compile this driver as a module, choose M here: the module
will be called pwm-samsung.
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 4527f09a5c50..fb04a439462c 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -532,6 +532,15 @@ int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
struct pwm_chip *chip;
int err;
+ /*
+ * Some lowlevel driver's implementations of .apply() make use of
+ * mutexes, also with some drivers only returning when the new
+ * configuration is active calling pwm_apply_state() from atomic context
+ * is a bad idea. So make it explicit that calling this function might
+ * sleep.
+ */
+ might_sleep();
+
if (!pwm || !state || !state->period ||
state->duty_cycle > state->period)
return -EINVAL;
diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index e748604403cc..98b34ea9f38e 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -24,7 +24,6 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
-#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
index dd94c4312a0c..0a4ff55fad04 100644
--- a/drivers/pwm/pwm-samsung.c
+++ b/drivers/pwm/pwm-samsung.c
@@ -117,6 +117,20 @@ static inline unsigned int to_tcon_channel(unsigned int channel)
return (channel == 0) ? 0 : (channel + 1);
}
+static void __pwm_samsung_manual_update(struct samsung_pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
+ u32 tcon;
+
+ tcon = readl(chip->base + REG_TCON);
+ tcon |= TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, chip->base + REG_TCON);
+
+ tcon &= ~TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, chip->base + REG_TCON);
+}
+
static void pwm_samsung_set_divisor(struct samsung_pwm_chip *pwm,
unsigned int channel, u8 divisor)
{
@@ -276,6 +290,13 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm)
tcon &= ~TCON_AUTORELOAD(tcon_chan);
writel(tcon, our_chip->base + REG_TCON);
+ /*
+ * In case the PWM is at 100% duty cycle, force a manual
+ * update to prevent the signal from staying high.
+ */
+ if (readl(our_chip->base + REG_TCMPB(pwm->hwpwm)) == (u32)-1U)
+ __pwm_samsung_manual_update(our_chip, pwm);
+
our_chip->disabled_mask |= BIT(pwm->hwpwm);
spin_unlock_irqrestore(&samsung_pwm_lock, flags);
@@ -284,18 +305,11 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm)
static void pwm_samsung_manual_update(struct samsung_pwm_chip *chip,
struct pwm_device *pwm)
{
- unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
- u32 tcon;
unsigned long flags;
spin_lock_irqsave(&samsung_pwm_lock, flags);
- tcon = readl(chip->base + REG_TCON);
- tcon |= TCON_MANUALUPDATE(tcon_chan);
- writel(tcon, chip->base + REG_TCON);
-
- tcon &= ~TCON_MANUALUPDATE(tcon_chan);
- writel(tcon, chip->base + REG_TCON);
+ __pwm_samsung_manual_update(chip, pwm);
spin_unlock_irqrestore(&samsung_pwm_lock, flags);
}
diff --git a/drivers/pwm/pwm-visconti.c b/drivers/pwm/pwm-visconti.c
index af4e37d3e3a6..927c4cbb1daf 100644
--- a/drivers/pwm/pwm-visconti.c
+++ b/drivers/pwm/pwm-visconti.c
@@ -144,28 +144,17 @@ static int visconti_pwm_probe(struct platform_device *pdev)
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
- platform_set_drvdata(pdev, priv);
-
priv->chip.dev = dev;
priv->chip.ops = &visconti_pwm_ops;
priv->chip.npwm = 4;
- ret = pwmchip_add(&priv->chip);
+ ret = devm_pwmchip_add(&pdev->dev, &priv->chip);
if (ret < 0)
return dev_err_probe(&pdev->dev, ret, "Cannot register visconti PWM\n");
return 0;
}
-static int visconti_pwm_remove(struct platform_device *pdev)
-{
- struct visconti_pwm_chip *priv = platform_get_drvdata(pdev);
-
- pwmchip_remove(&priv->chip);
-
- return 0;
-}
-
static const struct of_device_id visconti_pwm_of_match[] = {
{ .compatible = "toshiba,visconti-pwm", },
{ }
@@ -178,7 +167,6 @@ static struct platform_driver visconti_pwm_driver = {
.of_match_table = visconti_pwm_of_match,
},
.probe = visconti_pwm_probe,
- .remove = visconti_pwm_remove,
};
module_platform_driver(visconti_pwm_driver);
diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
index ea2aa151080a..480bfc29782f 100644
--- a/drivers/pwm/pwm-vt8500.c
+++ b/drivers/pwm/pwm-vt8500.c
@@ -56,7 +56,7 @@ struct vt8500_chip {
#define to_vt8500_chip(chip) container_of(chip, struct vt8500_chip, chip)
#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
-static inline void pwm_busy_wait(struct vt8500_chip *vt8500, int nr, u8 bitmask)
+static inline void vt8500_pwm_busy_wait(struct vt8500_chip *vt8500, int nr, u8 bitmask)
{
int loops = msecs_to_loops(10);
u32 mask = bitmask << (nr << 8);
@@ -106,18 +106,18 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
dc = c;
writel(prescale, vt8500->base + REG_SCALAR(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_SCALAR_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_SCALAR_UPDATE);
writel(pv, vt8500->base + REG_PERIOD(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_PERIOD_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_PERIOD_UPDATE);
writel(dc, vt8500->base + REG_DUTY(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_DUTY_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_DUTY_UPDATE);
val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
val |= CTRL_AUTOLOAD;
writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
clk_disable(vt8500->clk);
return 0;
@@ -138,7 +138,7 @@ static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
val |= CTRL_ENABLE;
writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
return 0;
}
@@ -151,7 +151,7 @@ static void vt8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
val = readl(vt8500->base + REG_CTRL(pwm->hwpwm));
val &= ~CTRL_ENABLE;
writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
clk_disable(vt8500->clk);
}
@@ -171,7 +171,7 @@ static int vt8500_pwm_set_polarity(struct pwm_chip *chip,
val &= ~CTRL_INVERT;
writel(val, vt8500->base + REG_CTRL(pwm->hwpwm));
- pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
+ vt8500_pwm_busy_wait(vt8500, pwm->hwpwm, STATUS_CTRL_UPDATE);
return 0;
}