[PATCH v2 4/6] media: imx208: Support device probe in non-zero ACPI D state

Bingbu Cao
2021-12-15T11:12:26Z

drivers/media/i2c/imx208.c | 82 ++++++++++++++++++++++++++++++----------------
1 file changed, 53 insertions(+), 29 deletions(-)

diff --git a/drivers/media/i2c/imx208.c b/drivers/media/i2c/imx208.c
index 6f3d9c1b5879..b9516b2f1c15 100644
--- a/drivers/media/i2c/imx208.c
+++ b/drivers/media/i2c/imx208.c
@@ -296,6 +296,9 @@ struct imx208 {
/* OTP data */
bool otp_read;
char otp_data[IMX208_OTP_SIZE];
+
+ /* True if the device has been identified */
+ bool identified;
};

static inline struct imx208 *to_imx208(struct v4l2_subdev *_sd)
@@ -619,6 +622,34 @@ static int imx208_set_pad_format(struct v4l2_subdev *sd,
return 0;
}

+static int imx208_identify_module(struct imx208 *imx208)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&imx208->sd);
+ int ret;
+ u32 val;
+
+ if (imx208->identified)
+ return 0;
+
+ ret = imx208_read_reg(imx208, IMX208_REG_CHIP_ID,
+ 2, &val);
+ if (ret) {
+ dev_err(&client->dev, "failed to read chip id %x\n",
+ IMX208_CHIP_ID);
+ return ret;
+ }
+
+ if (val != IMX208_CHIP_ID) {
+ dev_err(&client->dev, "chip id mismatch: %x!=%x\n",
+ IMX208_CHIP_ID, val);
+ return -EIO;
+ }
+
+ imx208->identified = true;
+
+ return 0;
+}
+
/* Start streaming */
static int imx208_start_streaming(struct imx208 *imx208)
{
@@ -626,6 +657,10 @@ static int imx208_start_streaming(struct imx208 *imx208)
const struct imx208_reg_list *reg_list;
int ret, link_freq_index;

+ ret = imx208_identify_module(imx208);
+ if (ret)
+ return ret;
+
/* Setup PLL */
link_freq_index = imx208->cur_mode->link_freq_index;
reg_list = &link_freq_configs[link_freq_index].reg_list;
@@ -752,29 +787,6 @@ static int __maybe_unused imx208_resume(struct device *dev)
}

/* Verify chip ID */
-static int imx208_identify_module(struct imx208 *imx208)
-{
- struct i2c_client *client = v4l2_get_subdevdata(&imx208->sd);
- int ret;
- u32 val;
-
- ret = imx208_read_reg(imx208, IMX208_REG_CHIP_ID,
- 2, &val);
- if (ret) {
- dev_err(&client->dev, "failed to read chip id %x\n",
- IMX208_CHIP_ID);
- return ret;
- }
-
- if (val != IMX208_CHIP_ID) {
- dev_err(&client->dev, "chip id mismatch: %x!=%x\n",
- IMX208_CHIP_ID, val);
- return -EIO;
- }
-
- return 0;
-}
-
static const struct v4l2_subdev_video_ops imx208_video_ops = {
.s_stream = imx208_set_stream,
};
@@ -813,6 +825,10 @@ static int imx208_read_otp(struct imx208 *imx208)
goto out_unlock;
}

+ ret = imx208_identify_module(imx208);
+ if (ret)
+ goto out_pm_put;
+
/* Write register address */
msgs[0].addr = client->addr;
msgs[0].flags = 0;
@@ -831,6 +847,7 @@ static int imx208_read_otp(struct imx208 *imx208)
ret = 0;
}

+out_pm_put:
pm_runtime_put(&client->dev);

out_unlock:
@@ -961,6 +978,7 @@ static int imx208_probe(struct i2c_client *client)
{
struct imx208 *imx208;
int ret;
+ bool full_power;
u32 val = 0;

device_property_read_u32(&client->dev, "clock-frequency", &val);
@@ -978,11 +996,14 @@ static int imx208_probe(struct i2c_client *client)
/* Initialize subdev */
v4l2_i2c_subdev_init(&imx208->sd, client, &imx208_subdev_ops);

- /* Check module identity */
- ret = imx208_identify_module(imx208);
- if (ret) {
- dev_err(&client->dev, "failed to find sensor: %d", ret);
- goto error_probe;
+ full_power = acpi_dev_state_d0(&client->dev);
+ if (full_power) {
+ /* Check module identity */
+ ret = imx208_identify_module(imx208);
+ if (ret) {
+ dev_err(&client->dev, "failed to find sensor: %d", ret);
+ goto error_probe;
+ }
}

/* Set default mode to max resolution */
@@ -1017,7 +1038,9 @@ static int imx208_probe(struct i2c_client *client)
goto error_async_subdev;
}

- 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);

@@ -1077,6 +1100,7 @@ static struct i2c_driver imx208_i2c_driver = {
},
.probe_new = imx208_probe,
.remove = imx208_remove,
+ .flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,
};

module_i2c_driver(imx208_i2c_driver);
--
2.7.4