[PATCH v2 3/6] media: ov2740: support device probe in non-zero ACPI D state

Bingbu Cao
2021-12-15T11:12:22Z

drivers/media/i2c/ov2740.c | 69 ++++++++++++++++++++++++++++++----------------
1 file changed, 45 insertions(+), 24 deletions(-)

diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
index 934c9d65cb09..bab720c7c1de 100644
--- a/drivers/media/i2c/ov2740.c
+++ b/drivers/media/i2c/ov2740.c
@@ -345,6 +345,9 @@ struct ov2740 {

/* NVM data inforamtion */
struct nvm_data *nvm;
+
+ /* True if the device has been identified */
+ bool identified;
};

static inline struct ov2740 *to_ov2740(struct v4l2_subdev *subdev)
@@ -440,6 +443,30 @@ static int ov2740_write_reg_list(struct ov2740 *ov2740,
return 0;
}

+static int ov2740_identify_module(struct ov2740 *ov2740)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
+ int ret;
+ u32 val;
+
+ if (ov2740->identified)
+ return 0;
+
+ ret = ov2740_read_reg(ov2740, OV2740_REG_CHIP_ID, 3, &val);
+ if (ret)
+ return ret;
+
+ if (val != OV2740_CHIP_ID) {
+ dev_err(&client->dev, "chip id mismatch: %x!=%x",
+ OV2740_CHIP_ID, val);
+ return -ENXIO;
+ }
+
+ ov2740->identified = true;
+
+ return 0;
+}
+
static int ov2740_update_digital_gain(struct ov2740 *ov2740, u32 d_gain)
{
int ret = 0;
@@ -724,6 +751,10 @@ static int ov2740_start_streaming(struct ov2740 *ov2740)
int link_freq_index;
int ret = 0;

+ ret = ov2740_identify_module(ov2740);
+ if (ret)
+ return ret;
+
ov2740_load_otp_data(nvm);

link_freq_index = ov2740->cur_mode->link_freq_index;
@@ -956,25 +987,6 @@ static const struct v4l2_subdev_internal_ops ov2740_internal_ops = {
.open = ov2740_open,
};

-static int ov2740_identify_module(struct ov2740 *ov2740)
-{
- struct i2c_client *client = v4l2_get_subdevdata(&ov2740->sd);
- int ret;
- u32 val;
-
- ret = ov2740_read_reg(ov2740, OV2740_REG_CHIP_ID, 3, &val);
- if (ret)
- return ret;
-
- if (val != OV2740_CHIP_ID) {
- dev_err(&client->dev, "chip id mismatch: %x!=%x",
- OV2740_CHIP_ID, val);
- return -ENXIO;
- }
-
- return 0;
-}
-
static int ov2740_check_hwcfg(struct device *dev)
{
struct fwnode_handle *ep;
@@ -1137,6 +1149,7 @@ static int ov2740_probe(struct i2c_client *client)
{
struct ov2740 *ov2740;
int ret = 0;
+ bool full_power;

ret = ov2740_check_hwcfg(&client->dev);
if (ret) {
@@ -1149,6 +1162,15 @@ static int ov2740_probe(struct i2c_client *client)
if (!ov2740)
return -ENOMEM;

+ full_power = acpi_dev_state_d0(&client->dev);
+ if (full_power) {
+ ret = ov2740_identify_module(ov2740);
+ if (ret) {
+ dev_err(&client->dev, "failed to find sensor: %d", ret);
+ return ret;
+ }
+ }
+
v4l2_i2c_subdev_init(&ov2740->sd, client, &ov2740_subdev_ops);
ret = ov2740_identify_module(ov2740);
if (ret) {
@@ -1186,11 +1208,9 @@ static int ov2740_probe(struct i2c_client *client)
if (ret)
dev_warn(&client->dev, "register nvmem failed, ret %d\n", ret);

- /*
- * 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);

@@ -1225,6 +1245,7 @@ static struct i2c_driver ov2740_i2c_driver = {
},
.probe_new = ov2740_probe,
.remove = ov2740_remove,
+ .flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,
};

module_i2c_driver(ov2740_i2c_driver);
--
2.7.4