ARM: SAMSUNG: Add suspend/resume support for S3C PWM driver

Reset period_ns and duty_ns values in suspend handler to avoid skip of
configuration if same values passed to pwm_config;
Restore invertion bit in resume handler.

Without this patch PWM works incorrectly after resume from suspend.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

diff --git a/arch/arm/plat-samsung/pwm.c b/arch/arm/plat-samsung/pwm.c
index ef019f27b67d5822afc8c3e4fbdac17220eebbd6..f2d11390d01c8d4e3227e50d8a74273726d00695 100644 (file)
--- a/arch/arm/plat-samsung/pwm.c
+++ b/arch/arm/plat-samsung/pwm.c
@@ -379,6 +379,39 @@ static int __devexit s3c_pwm_remove(struct platform_device *pdev)
        return 0;
 }
 
+#ifdef CONFIG_PM
+static int s3c_pwm_suspend(struct platform_device *pdev, pm_message_t state)
+{
+       struct pwm_device *pwm = 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;
+
+       return 0;
+}
+
+static int s3c_pwm_resume(struct platform_device *pdev)
+{
+       struct pwm_device *pwm = platform_get_drvdata(pdev);
+       unsigned long tcon;
+
+       /* Restore invertion */
+       tcon = __raw_readl(S3C2410_TCON);
+       tcon |= pwm_tcon_invert(pwm);
+       __raw_writel(tcon, S3C2410_TCON);
+
+       return 0;
+}
+
+#else
+#define s3c_pwm_suspend NULL
+#define s3c_pwm_resume NULL
+#endif
+
 static struct platform_driver s3c_pwm_driver = {
        .driver         = {
                .name   = "s3c24xx-pwm",
@@ -386,6 +419,8 @@ static struct platform_driver s3c_pwm_driver = {
        },
        .probe          = s3c_pwm_probe,
        .remove         = __devexit_p(s3c_pwm_remove),
+       .suspend        = s3c_pwm_suspend,
+       .resume         = s3c_pwm_resume,
 };
 
 static int __init pwm_init(void)