i2c-core: i2c bus should support PM entries in struct dev_pm_ops

Struct dev_pm_ops is not configured in current i2c bus type. i2c drivers
only depends on suspend/resume entries in struct dev_pm_ops are not
informed of PM suspend and resume events by i2c framework.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 35 insertions, 0 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 9065c7238b5e..0ac2f90ab840 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -155,6 +155,35 @@ static void i2c_device_shutdown(struct device *dev)
                 driver->shutdown(client);
 }
 
+#ifdef CONFIG_SUSPEND
+static int i2c_device_pm_suspend(struct device *dev)
+{
+        const struct dev_pm_ops *pm;
+
+        if (!dev->driver)
+                return 0;
+        pm = dev->driver->pm;
+        if (!pm || !pm->suspend)
+                return 0;
+        return pm->suspend(dev);
+}
+
+static int i2c_device_pm_resume(struct device *dev)
+{
+        const struct dev_pm_ops *pm;
+
+        if (!dev->driver)
+                return 0;
+        pm = dev->driver->pm;
+        if (!pm || !pm->resume)
+                return 0;
+        return pm->resume(dev);
+}
+#else
+#define i2c_device_pm_suspend   NULL
+#define i2c_device_pm_resume    NULL
+#endif
+
 static int i2c_device_suspend(struct device *dev, pm_message_t mesg)
 {
         struct i2c_client *client = i2c_verify_client(dev);
@@ -219,6 +248,11 @@ static const struct attribute_group *i2c_dev_attr_groups[] = {
         NULL
 };
 
+const static struct dev_pm_ops i2c_device_pm_ops = {
+        .suspend = i2c_device_pm_suspend,
+        .resume = i2c_device_pm_resume,
+};
+
 struct bus_type i2c_bus_type = {
         .name           = "i2c",
         .match          = i2c_device_match,
@@ -227,6 +261,7 @@ struct bus_type i2c_bus_type = {
         .shutdown       = i2c_device_shutdown,
         .suspend        = i2c_device_suspend,
         .resume         = i2c_device_resume,
+        .pm             = &i2c_device_pm_ops,
 };
 EXPORT_SYMBOL_GPL(i2c_bus_type);