ARM Samsung: Move s3c pwm driver to pwm framework
authorSascha Hauer <s.hauer@pengutronix.de>
Thu, 15 Mar 2012 09:04:36 +0000 (10:04 +0100)
committerThierry Reding <thierry.reding@avionic-design.de>
Mon, 2 Jul 2012 19:39:02 +0000 (21:39 +0200)
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 BĂ©nard <eric@eukrea.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
arch/arm/plat-samsung/Makefile
drivers/pwm/Kconfig
drivers/pwm/Makefile
drivers/pwm/pwm-samsung.c [moved from arch/arm/plat-samsung/pwm.c with 58% similarity]

index 860b2db..9685472 100644 (file)
@@ -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
index a9a9715..0d9aa92 100644 (file)
@@ -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
index 3dd1b83..a1d87b1 100644 (file)
@@ -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
similarity index 58%
rename from arch/arm/plat-samsung/pwm.c
rename to drivers/pwm/pwm-samsung.c
index c559d84..c40c37e 100644 (file)
@@ -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;