media: hi556: 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: Kao, Arec <arec.kao@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/hi556.c b/drivers/media/i2c/hi556.c
index 8db1cbedc1fd8750a468613892d833b5db166200..055d1aa8410e54126d6a9809ccbece85a15415c9 100644 (file)
--- a/drivers/media/i2c/hi556.c
+++ b/drivers/media/i2c/hi556.c
@@ -495,6 +495,9 @@ struct hi556 {
 
        /* Streaming on/off */
        bool streaming;
+
+       /* True if the device has been identified */
+       bool identified;
 };
 
 static u64 to_pixel_rate(u32 f_index)
@@ -757,12 +760,41 @@ static void hi556_assign_pad_format(const struct hi556_mode *mode,
        fmt->field = V4L2_FIELD_NONE;
 }
 
+static int hi556_identify_module(struct hi556 *hi556)
+{
+       struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+       int ret;
+       u32 val;
+
+       if (hi556->identified)
+               return 0;
+
+       ret = hi556_read_reg(hi556, HI556_REG_CHIP_ID,
+                            HI556_REG_VALUE_16BIT, &val);
+       if (ret)
+               return ret;
+
+       if (val != HI556_CHIP_ID) {
+               dev_err(&client->dev, "chip id mismatch: %x!=%x",
+                       HI556_CHIP_ID, val);
+               return -ENXIO;
+       }
+
+       hi556->identified = true;
+
+       return 0;
+}
+
 static int hi556_start_streaming(struct hi556 *hi556)
 {
        struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
        const struct hi556_reg_list *reg_list;
        int link_freq_index, ret;
 
+       ret = hi556_identify_module(hi556);
+       if (ret)
+               return ret;
+
        link_freq_index = hi556->cur_mode->link_freq_index;
        reg_list = &link_freq_configs[link_freq_index].reg_list;
        ret = hi556_write_reg_list(hi556, reg_list);
@@ -1001,26 +1033,6 @@ static const struct v4l2_subdev_internal_ops hi556_internal_ops = {
        .open = hi556_open,
 };
 
-static int hi556_identify_module(struct hi556 *hi556)
-{
-       struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
-       int ret;
-       u32 val;
-
-       ret = hi556_read_reg(hi556, HI556_REG_CHIP_ID,
-                            HI556_REG_VALUE_16BIT, &val);
-       if (ret)
-               return ret;
-
-       if (val != HI556_CHIP_ID) {
-               dev_err(&client->dev, "chip id mismatch: %x!=%x",
-                       HI556_CHIP_ID, val);
-               return -ENXIO;
-       }
-
-       return 0;
-}
-
 static int hi556_check_hwcfg(struct device *dev)
 {
        struct fwnode_handle *ep;
@@ -1106,6 +1118,7 @@ static int hi556_remove(struct i2c_client *client)
 static int hi556_probe(struct i2c_client *client)
 {
        struct hi556 *hi556;
+       bool full_power;
        int ret;
 
        ret = hi556_check_hwcfg(&client->dev);
@@ -1120,10 +1133,14 @@ static int hi556_probe(struct i2c_client *client)
                return -ENOMEM;
 
        v4l2_i2c_subdev_init(&hi556->sd, client, &hi556_subdev_ops);
-       ret = hi556_identify_module(hi556);
-       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 = hi556_identify_module(hi556);
+               if (ret) {
+                       dev_err(&client->dev, "failed to find sensor: %d", ret);
+                       return ret;
+               }
        }
 
        mutex_init(&hi556->mutex);
@@ -1152,7 +1169,9 @@ static int hi556_probe(struct i2c_client *client)
                goto probe_error_media_entity_cleanup;
        }
 
-       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);
 
@@ -1189,6 +1208,7 @@ static struct i2c_driver hi556_i2c_driver = {
        },
        .probe_new = hi556_probe,
        .remove = hi556_remove,
+       .flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,
 };
 
 module_i2c_driver(hi556_i2c_driver);