3 files changed, 37 insertions, 0 deletions

diff --git a/drivers/pwm/pwm-lpss-platform.c b/drivers/pwm/pwm-lpss-platform.c
index 5d6ed1507d29..5561b9e190f8 100644
--- a/drivers/pwm/pwm-lpss-platform.c
+++ b/drivers/pwm/pwm-lpss-platform.c
@@ -74,6 +74,10 @@ static int pwm_lpss_remove_platform(struct platform_device *pdev)
         return pwm_lpss_remove(lpwm);
 }
 
+static SIMPLE_DEV_PM_OPS(pwm_lpss_platform_pm_ops,
+                         pwm_lpss_suspend,
+                         pwm_lpss_resume);
+
 static const struct acpi_device_id pwm_lpss_acpi_match[] = {
         { "80860F09", (unsigned long)&pwm_lpss_byt_info },
         { "80862288", (unsigned long)&pwm_lpss_bsw_info },
@@ -86,6 +90,7 @@ static struct platform_driver pwm_lpss_driver_platform = {
         .driver = {
                 .name = "pwm-lpss",
                 .acpi_match_table = pwm_lpss_acpi_match,
+                .pm = &pwm_lpss_platform_pm_ops,
         },
         .probe = pwm_lpss_probe_platform,
         .remove = pwm_lpss_remove_platform,
diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c
index 8db0d40ccacd..4721a264bac2 100644
--- a/drivers/pwm/pwm-lpss.c
+++ b/drivers/pwm/pwm-lpss.c
@@ -32,10 +32,13 @@
 /* Size of each PWM register space if multiple */
 #define PWM_SIZE                        0x400
 
+#define MAX_PWMS                        4
+
 struct pwm_lpss_chip {
         struct pwm_chip chip;
         void __iomem *regs;
         const struct pwm_lpss_boardinfo *info;
+        u32 saved_ctrl[MAX_PWMS];
 };
 
 static inline struct pwm_lpss_chip *to_lpwm(struct pwm_chip *chip)
@@ -177,6 +180,9 @@ struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev, struct resource *r,
         unsigned long c;
         int ret;
 
+        if (WARN_ON(info->npwm > MAX_PWMS))
+                return ERR_PTR(-ENODEV);
+
         lpwm = devm_kzalloc(dev, sizeof(*lpwm), GFP_KERNEL);
         if (!lpwm)
                 return ERR_PTR(-ENOMEM);
@@ -212,6 +218,30 @@ int pwm_lpss_remove(struct pwm_lpss_chip *lpwm)
 }
 EXPORT_SYMBOL_GPL(pwm_lpss_remove);
 
+int pwm_lpss_suspend(struct device *dev)
+{
+        struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev);
+        int i;
+
+        for (i = 0; i < lpwm->info->npwm; i++)
+                lpwm->saved_ctrl[i] = readl(lpwm->regs + i * PWM_SIZE + PWM);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(pwm_lpss_suspend);
+
+int pwm_lpss_resume(struct device *dev)
+{
+        struct pwm_lpss_chip *lpwm = dev_get_drvdata(dev);
+        int i;
+
+        for (i = 0; i < lpwm->info->npwm; i++)
+                writel(lpwm->saved_ctrl[i], lpwm->regs + i * PWM_SIZE + PWM);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(pwm_lpss_resume);
+
 MODULE_DESCRIPTION("PWM driver for Intel LPSS");
 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/pwm/pwm-lpss.h b/drivers/pwm/pwm-lpss.h
index 98306bb02cfe..7a4238ad1fcb 100644
--- a/drivers/pwm/pwm-lpss.h
+++ b/drivers/pwm/pwm-lpss.h
@@ -28,5 +28,7 @@ struct pwm_lpss_boardinfo {
 struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev, struct resource *r,
                                      const struct pwm_lpss_boardinfo *info);
 int pwm_lpss_remove(struct pwm_lpss_chip *lpwm);
+int pwm_lpss_suspend(struct device *dev);
+int pwm_lpss_resume(struct device *dev);
 
 #endif  /* __PWM_LPSS_H */