media: ov5675: Support device probe in non-zero ACPI D state

Tell ACPI device PM code that the driver supports the device being in
non-zero ACPI D state when the driver's probe function is entered.

Also do identification on the first access of the device, whether in probe
or when starting streaming.

Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/i2c/ov5675.c b/drivers/media/i2c/ov5675.c
index da5850b7ad07fc2703b59a3a5500d9f848701d73..00925850fa7cac357ed30c90171d9db65a0208a5 100644 (file)
--- a/drivers/media/i2c/ov5675.c
+++ b/drivers/media/i2c/ov5675.c
@@ -493,6 +493,9 @@ struct ov5675 {
 
        /* Streaming on/off */
        bool streaming;
+
+       /* True if the device has been identified */
+       bool identified;
 };
 
 static u64 to_pixel_rate(u32 f_index)
@@ -808,12 +811,41 @@ static void ov5675_update_pad_format(const struct ov5675_mode *mode,
        fmt->field = V4L2_FIELD_NONE;
 }
 
+static int ov5675_identify_module(struct ov5675 *ov5675)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&ov5675->sd);
+       int ret;
+       u32 val;
+
+       if (ov5675->identified)
+               return 0;
+
+       ret = ov5675_read_reg(ov5675, OV5675_REG_CHIP_ID,
+                             OV5675_REG_VALUE_24BIT, &val);
+       if (ret)
+               return ret;
+
+       if (val != OV5675_CHIP_ID) {
+               dev_err(&client->dev, "chip id mismatch: %x!=%x",
+                       OV5675_CHIP_ID, val);
+               return -ENXIO;
+       }
+
+       ov5675->identified = true;
+
+       return 0;
+}
+
 static int ov5675_start_streaming(struct ov5675 *ov5675)
 {
        struct i2c_client *client = v4l2_get_subdevdata(&ov5675->sd);
        const struct ov5675_reg_list *reg_list;
        int link_freq_index, ret;
 
+       ret = ov5675_identify_module(ov5675);
+       if (ret)
+               return ret;
+
        link_freq_index = ov5675->cur_mode->link_freq_index;
        reg_list = &link_freq_configs[link_freq_index].reg_list;
        ret = ov5675_write_reg_list(ov5675, reg_list);
@@ -1048,26 +1080,6 @@ static const struct v4l2_subdev_internal_ops ov5675_internal_ops = {
        .open = ov5675_open,
 };
 
-static int ov5675_identify_module(struct ov5675 *ov5675)
-{
-       struct i2c_client *client = v4l2_get_subdevdata(&ov5675->sd);
-       int ret;
-       u32 val;
-
-       ret = ov5675_read_reg(ov5675, OV5675_REG_CHIP_ID,
-                             OV5675_REG_VALUE_24BIT, &val);
-       if (ret)
-               return ret;
-
-       if (val != OV5675_CHIP_ID) {
-               dev_err(&client->dev, "chip id mismatch: %x!=%x",
-                       OV5675_CHIP_ID, val);
-               return -ENXIO;
-       }
-
-       return 0;
-}
-
 static int ov5675_check_hwcfg(struct device *dev)
 {
        struct fwnode_handle *ep;
@@ -1154,6 +1166,7 @@ static int ov5675_remove(struct i2c_client *client)
 static int ov5675_probe(struct i2c_client *client)
 {
        struct ov5675 *ov5675;
+       bool full_power;
        int ret;
 
        ret = ov5675_check_hwcfg(&client->dev);
@@ -1168,10 +1181,14 @@ static int ov5675_probe(struct i2c_client *client)
                return -ENOMEM;
 
        v4l2_i2c_subdev_init(&ov5675->sd, client, &ov5675_subdev_ops);
-       ret = ov5675_identify_module(ov5675);
-       if (ret) {
-               dev_err(&client->dev, "failed to find sensor: %d", ret);
-               return ret;
+
+       full_power = acpi_dev_state_d0(&client->dev);
+       if (full_power) {
+               ret = ov5675_identify_module(ov5675);
+               if (ret) {
+                       dev_err(&client->dev, "failed to find sensor: %d", ret);
+                       return ret;
+               }
        }
 
        mutex_init(&ov5675->mutex);
@@ -1204,7 +1221,10 @@ static int ov5675_probe(struct i2c_client *client)
         * Device is already turned on by i2c-core with ACPI domain PM.
         * Enable runtime PM and turn off the device.
         */
-       pm_runtime_set_active(&client->dev);
+
+       /* Set the device's state to active if it's in D0 state. */
+       if (full_power)
+               pm_runtime_set_active(&client->dev);
        pm_runtime_enable(&client->dev);
        pm_runtime_idle(&client->dev);
 
@@ -1241,6 +1261,7 @@ static struct i2c_driver ov5675_i2c_driver = {
        },
        .probe_new = ov5675_probe,
        .remove = ov5675_remove,
+       .flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,
 };
 
 module_i2c_driver(ov5675_i2c_driver);