ARM Samsung: Move s3c pwm driver to pwm framework

Move the driver to drivers/pwm/ and convert it to use the framework.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
[eric@eukrea.com: fix pwmchip_add return code test]
Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

arch/arm/plat-samsung/Makefile

@@ -63,7 +63,3 @@ obj-$(CONFIG_S5P_SLEEP)		+= s5p-sleep.o
 # PD support
 
 obj-$(CONFIG_SAMSUNG_PD)	+= pd.o
-
-# PWM support
-
-obj-$(CONFIG_HAVE_PWM)		+= pwm.o

drivers/pwm/Kconfig

@@ -36,6 +36,15 @@ config PWM_PXA
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-pxa.
 
+config PWM_SAMSUNG
+	tristate "Samsung pwm support"
+	depends on PLAT_SAMSUNG
+	help
+	  Generic PWM framework driver for Samsung.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-samsung.
+
 config PWM_TEGRA
 	tristate "NVIDIA Tegra PWM support"
 	depends on ARCH_TEGRA

drivers/pwm/Makefile

@@ -2,4 +2,5 @@ obj-$(CONFIG_PWM)		+= core.o
 obj-$(CONFIG_PWM_BFIN)		+= pwm-bfin.o
 obj-$(CONFIG_PWM_IMX)		+= pwm-imx.o
 obj-$(CONFIG_PWM_PXA)		+= pwm-pxa.o
+obj-$(CONFIG_PWM_SAMSUNG)	+= pwm-samsung.o
 obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o

arch/arm/plat-samsung/pwm.c → drivers/pwm/pwm-samsung.c

@@ -24,8 +24,7 @@
 
 #include <plat/regs-timer.h>
 
-struct pwm_device {
-	struct list_head	 list;
+struct s3c_chip {
 	struct platform_device	*pdev;
 
 	struct clk		*clk_div;
@@ -36,117 +35,65 @@ struct pwm_device {
 	unsigned int		 duty_ns;
 
 	unsigned char		 tcon_base;
-	unsigned char		 running;
-	unsigned char		 use_count;
 	unsigned char		 pwm_id;
+	struct pwm_chip		 chip;
 };
 
+#define to_s3c_chip(chip)	container_of(chip, struct s3c_chip, chip)
+
 #define pwm_dbg(_pwm, msg...) dev_dbg(&(_pwm)->pdev->dev, msg)
 
 static struct clk *clk_scaler[2];
 
-static inline int pwm_is_tdiv(struct pwm_device *pwm)
-{
-	return clk_get_parent(pwm->clk) == pwm->clk_div;
-}
-
-static DEFINE_MUTEX(pwm_lock);
-static LIST_HEAD(pwm_list);
-
-struct pwm_device *pwm_request(int pwm_id, const char *label)
-{
-	struct pwm_device *pwm;
-	int found = 0;
-
-	mutex_lock(&pwm_lock);
-
-	list_for_each_entry(pwm, &pwm_list, list) {
-		if (pwm->pwm_id == pwm_id) {
-			found = 1;
-			break;
-		}
-	}
-
-	if (found) {
-		if (pwm->use_count == 0) {
-			pwm->use_count = 1;
-			pwm->label = label;
-		} else
-			pwm = ERR_PTR(-EBUSY);
-	} else
-		pwm = ERR_PTR(-ENOENT);
-
-	mutex_unlock(&pwm_lock);
-	return pwm;
-}
-
-EXPORT_SYMBOL(pwm_request);
-
-
-void pwm_free(struct pwm_device *pwm)
+static inline int pwm_is_tdiv(struct s3c_chip *chip)
 {
-	mutex_lock(&pwm_lock);
-
-	if (pwm->use_count) {
-		pwm->use_count--;
-		pwm->label = NULL;
-	} else
-		printk(KERN_ERR "PWM%d device already freed\n", pwm->pwm_id);
-
-	mutex_unlock(&pwm_lock);
+	return clk_get_parent(chip->clk) == chip->clk_div;
 }
 
-EXPORT_SYMBOL(pwm_free);
-
 #define pwm_tcon_start(pwm) (1 << (pwm->tcon_base + 0))
 #define pwm_tcon_invert(pwm) (1 << (pwm->tcon_base + 2))
 #define pwm_tcon_autoreload(pwm) (1 << (pwm->tcon_base + 3))
 #define pwm_tcon_manulupdate(pwm) (1 << (pwm->tcon_base + 1))
 
-int pwm_enable(struct pwm_device *pwm)
+static int s3c_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
+	struct s3c_chip *s3c = to_s3c_chip(chip);
 	unsigned long flags;
 	unsigned long tcon;
 
 	local_irq_save(flags);
 
 	tcon = __raw_readl(S3C2410_TCON);
-	tcon |= pwm_tcon_start(pwm);
+	tcon |= pwm_tcon_start(s3c);
 	__raw_writel(tcon, S3C2410_TCON);
 
 	local_irq_restore(flags);
 
-	pwm->running = 1;
 	return 0;
 }
 
-EXPORT_SYMBOL(pwm_enable);
-
-void pwm_disable(struct pwm_device *pwm)
+static void s3c_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
+	struct s3c_chip *s3c = to_s3c_chip(chip);
 	unsigned long flags;
 	unsigned long tcon;
 
 	local_irq_save(flags);
 
 	tcon = __raw_readl(S3C2410_TCON);
-	tcon &= ~pwm_tcon_start(pwm);
+	tcon &= ~pwm_tcon_start(s3c);
 	__raw_writel(tcon, S3C2410_TCON);
 
 	local_irq_restore(flags);
-
-	pwm->running = 0;
 }
 
-EXPORT_SYMBOL(pwm_disable);
-
-static unsigned long pwm_calc_tin(struct pwm_device *pwm, unsigned long freq)
+static unsigned long pwm_calc_tin(struct s3c_chip *s3c, unsigned long freq)
 {
 	unsigned long tin_parent_rate;
 	unsigned int div;
 
-	tin_parent_rate = clk_get_rate(clk_get_parent(pwm->clk_div));
-	pwm_dbg(pwm, "tin parent at %lu\n", tin_parent_rate);
+	tin_parent_rate = clk_get_rate(clk_get_parent(s3c->clk_div));
+	pwm_dbg(s3c, "tin parent at %lu\n", tin_parent_rate);
 
 	for (div = 2; div <= 16; div *= 2) {
 		if ((tin_parent_rate / (div << 16)) < freq)
@@ -158,8 +105,10 @@ static unsigned long pwm_calc_tin(struct pwm_device *pwm, unsigned long freq)
 
 #define NS_IN_HZ (1000000000UL)
 
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+static int s3c_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+		int duty_ns, int period_ns)
 {
+	struct s3c_chip *s3c = to_s3c_chip(chip);
 	unsigned long tin_rate;
 	unsigned long tin_ns;
 	unsigned long period;
@@ -178,38 +127,38 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
 	if (duty_ns > period_ns)
 		return -EINVAL;
 
-	if (period_ns == pwm->period_ns &&
-	    duty_ns == pwm->duty_ns)
+	if (period_ns == s3c->period_ns &&
+	    duty_ns == s3c->duty_ns)
 		return 0;
 
 	/* The TCMP and TCNT can be read without a lock, they're not
 	 * shared between the timers. */
 
-	tcmp = __raw_readl(S3C2410_TCMPB(pwm->pwm_id));
-	tcnt = __raw_readl(S3C2410_TCNTB(pwm->pwm_id));
+	tcmp = __raw_readl(S3C2410_TCMPB(s3c->pwm_id));
+	tcnt = __raw_readl(S3C2410_TCNTB(s3c->pwm_id));
 
 	period = NS_IN_HZ / period_ns;
 
-	pwm_dbg(pwm, "duty_ns=%d, period_ns=%d (%lu)\n",
+	pwm_dbg(s3c, "duty_ns=%d, period_ns=%d (%lu)\n",
 		duty_ns, period_ns, period);
 
 	/* Check to see if we are changing the clock rate of the PWM */
 
-	if (pwm->period_ns != period_ns) {
-		if (pwm_is_tdiv(pwm)) {
-			tin_rate = pwm_calc_tin(pwm, period);
-			clk_set_rate(pwm->clk_div, tin_rate);
+	if (s3c->period_ns != period_ns) {
+		if (pwm_is_tdiv(s3c)) {
+			tin_rate = pwm_calc_tin(s3c, period);
+			clk_set_rate(s3c->clk_div, tin_rate);
 		} else
-			tin_rate = clk_get_rate(pwm->clk);
+			tin_rate = clk_get_rate(s3c->clk);
 
-		pwm->period_ns = period_ns;
+		s3c->period_ns = period_ns;
 
-		pwm_dbg(pwm, "tin_rate=%lu\n", tin_rate);
+		pwm_dbg(s3c, "tin_rate=%lu\n", tin_rate);
 
 		tin_ns = NS_IN_HZ / tin_rate;
 		tcnt = period_ns / tin_ns;
 	} else
-		tin_ns = NS_IN_HZ / clk_get_rate(pwm->clk);
+		tin_ns = NS_IN_HZ / clk_get_rate(s3c->clk);
 
 	/* Note, counters count down */
 
@@ -220,7 +169,7 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
 	if (tcmp == tcnt)
 		tcmp--;
 
-	pwm_dbg(pwm, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);
+	pwm_dbg(s3c, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);
 
 	if (tcmp < 0)
 		tcmp = 0;
@@ -229,15 +178,15 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
 
 	local_irq_save(flags);
 
-	__raw_writel(tcmp, S3C2410_TCMPB(pwm->pwm_id));
-	__raw_writel(tcnt, S3C2410_TCNTB(pwm->pwm_id));
+	__raw_writel(tcmp, S3C2410_TCMPB(s3c->pwm_id));
+	__raw_writel(tcnt, S3C2410_TCNTB(s3c->pwm_id));
 
 	tcon = __raw_readl(S3C2410_TCON);
-	tcon |= pwm_tcon_manulupdate(pwm);
-	tcon |= pwm_tcon_autoreload(pwm);
+	tcon |= pwm_tcon_manulupdate(s3c);
+	tcon |= pwm_tcon_autoreload(s3c);
 	__raw_writel(tcon, S3C2410_TCON);
 
-	tcon &= ~pwm_tcon_manulupdate(pwm);
+	tcon &= ~pwm_tcon_manulupdate(s3c);
 	__raw_writel(tcon, S3C2410_TCON);
 
 	local_irq_restore(flags);
@@ -245,24 +194,17 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
 	return 0;
 }
 
-EXPORT_SYMBOL(pwm_config);
-
-static int pwm_register(struct pwm_device *pwm)
-{
-	pwm->duty_ns = -1;
-	pwm->period_ns = -1;
-
-	mutex_lock(&pwm_lock);
-	list_add_tail(&pwm->list, &pwm_list);
-	mutex_unlock(&pwm_lock);
-
-	return 0;
-}
+static struct pwm_ops s3c_pwm_ops = {
+	.enable = s3c_pwm_enable,
+	.disable = s3c_pwm_disable,
+	.config = s3c_pwm_config,
+	.owner = THIS_MODULE,
+};
 
 static int s3c_pwm_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct pwm_device *pwm;
+	struct s3c_chip *s3c;
 	unsigned long flags;
 	unsigned long tcon;
 	unsigned int id = pdev->id;
@@ -273,83 +215,87 @@ static int s3c_pwm_probe(struct platform_device *pdev)
 		return -ENXIO;
 	}
 
-	pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
-	if (pwm == NULL) {
+	s3c = kzalloc(sizeof(*s3c), GFP_KERNEL);
+	if (s3c == NULL) {
 		dev_err(dev, "failed to allocate pwm_device\n");
 		return -ENOMEM;
 	}
 
-	pwm->pdev = pdev;
-	pwm->pwm_id = id;
-
 	/* calculate base of control bits in TCON */
-	pwm->tcon_base = id == 0 ? 0 : (id * 4) + 4;
+	s3c->tcon_base = id == 0 ? 0 : (id * 4) + 4;
+	s3c->chip.ops = &s3c_pwm_ops;
+	s3c->chip.base = -1;
+	s3c->chip.npwm = 1;
 
-	pwm->clk = clk_get(dev, "pwm-tin");
-	if (IS_ERR(pwm->clk)) {
+	s3c->clk = clk_get(dev, "pwm-tin");
+	if (IS_ERR(s3c->clk)) {
 		dev_err(dev, "failed to get pwm tin clk\n");
-		ret = PTR_ERR(pwm->clk);
+		ret = PTR_ERR(s3c->clk);
 		goto err_alloc;
 	}
 
-	pwm->clk_div = clk_get(dev, "pwm-tdiv");
-	if (IS_ERR(pwm->clk_div)) {
+	s3c->clk_div = clk_get(dev, "pwm-tdiv");
+	if (IS_ERR(s3c->clk_div)) {
 		dev_err(dev, "failed to get pwm tdiv clk\n");
-		ret = PTR_ERR(pwm->clk_div);
+		ret = PTR_ERR(s3c->clk_div);
 		goto err_clk_tin;
 	}
 
-	clk_enable(pwm->clk);
-	clk_enable(pwm->clk_div);
+	clk_enable(s3c->clk);
+	clk_enable(s3c->clk_div);
 
 	local_irq_save(flags);
 
 	tcon = __raw_readl(S3C2410_TCON);
-	tcon |= pwm_tcon_invert(pwm);
+	tcon |= pwm_tcon_invert(s3c);
 	__raw_writel(tcon, S3C2410_TCON);
 
 	local_irq_restore(flags);
 
-
-	ret = pwm_register(pwm);
-	if (ret) {
+	ret = pwmchip_add(&s3c->chip);
+	if (ret < 0) {
 		dev_err(dev, "failed to register pwm\n");
 		goto err_clk_tdiv;
 	}
 
-	pwm_dbg(pwm, "config bits %02x\n",
-		(__raw_readl(S3C2410_TCON) >> pwm->tcon_base) & 0x0f);
+	pwm_dbg(s3c, "config bits %02x\n",
+		(__raw_readl(S3C2410_TCON) >> s3c->tcon_base) & 0x0f);
 
 	dev_info(dev, "tin at %lu, tdiv at %lu, tin=%sclk, base %d\n",
-		 clk_get_rate(pwm->clk),
-		 clk_get_rate(pwm->clk_div),
-		 pwm_is_tdiv(pwm) ? "div" : "ext", pwm->tcon_base);
+		 clk_get_rate(s3c->clk),
+		 clk_get_rate(s3c->clk_div),
+		 pwm_is_tdiv(s3c) ? "div" : "ext", s3c->tcon_base);
 
-	platform_set_drvdata(pdev, pwm);
+	platform_set_drvdata(pdev, s3c);
 	return 0;
 
  err_clk_tdiv:
-	clk_disable(pwm->clk_div);
-	clk_disable(pwm->clk);
-	clk_put(pwm->clk_div);
+	clk_disable(s3c->clk_div);
+	clk_disable(s3c->clk);
+	clk_put(s3c->clk_div);
 
  err_clk_tin:
-	clk_put(pwm->clk);
+	clk_put(s3c->clk);
 
  err_alloc:
-	kfree(pwm);
+	kfree(s3c);
 	return ret;
 }
 
 static int __devexit s3c_pwm_remove(struct platform_device *pdev)
 {
-	struct pwm_device *pwm = platform_get_drvdata(pdev);
+	struct s3c_chip *s3c = platform_get_drvdata(pdev);
+	int err;
+
+	err = pwmchip_remove(&s3c->chip);
+	if (err < 0)
+		return err;
 
-	clk_disable(pwm->clk_div);
-	clk_disable(pwm->clk);
-	clk_put(pwm->clk_div);
-	clk_put(pwm->clk);
-	kfree(pwm);
+	clk_disable(s3c->clk_div);
+	clk_disable(s3c->clk);
+	clk_put(s3c->clk_div);
+	clk_put(s3c->clk);
+	kfree(s3c);
 
 	return 0;
 }
@@ -357,26 +303,26 @@ static int __devexit s3c_pwm_remove(struct platform_device *pdev)
 #ifdef CONFIG_PM
 static int s3c_pwm_suspend(struct platform_device *pdev, pm_message_t state)
 {
-	struct pwm_device *pwm = platform_get_drvdata(pdev);
+	struct s3c_chip *s3c = platform_get_drvdata(pdev);
 
 	/* No one preserve these values during suspend so reset them
 	 * Otherwise driver leaves PWM unconfigured if same values
 	 * passed to pwm_config
 	 */
-	pwm->period_ns = 0;
-	pwm->duty_ns = 0;
+	s3c->period_ns = 0;
+	s3c->duty_ns = 0;
 
 	return 0;
 }
 
 static int s3c_pwm_resume(struct platform_device *pdev)
 {
-	struct pwm_device *pwm = platform_get_drvdata(pdev);
+	struct s3c_chip *s3c = platform_get_drvdata(pdev);
 	unsigned long tcon;
 
 	/* Restore invertion */
 	tcon = __raw_readl(S3C2410_TCON);
-	tcon |= pwm_tcon_invert(pwm);
+	tcon |= pwm_tcon_invert(s3c);
 	__raw_writel(tcon, S3C2410_TCON);
 
 	return 0;