[PATCH] media: ov8856: Do not check for for module version

From: Ricardo Ribalda
Date: Thu Mar 23 2023 - 18:44:36 EST


It the device is probed in non-zero ACPI D state, the module
identification is delayed until the first streamon.

The module identification has two parts: deviceID and version. To rea
the version we have to enable OTP read. This cannot be done during
streamon, becase it modifies REG_MODE_SELECT.

Since the driver has the same behaviour for all the module versions, do
not read the module version from the sensor's OTP.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 0e014f1a8d54 ("media: ov8856: support device probe in non-zero ACPI D state")
Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
To: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
To: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
To: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
To: Bingbu Cao <bingbu.cao@xxxxxxxxx>
Cc: Max Staudt <mstaudt@xxxxxxxxxxxx>
Cc: Jimmy Su <jimmy.su@xxxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Cc: linux-media@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/media/i2c/ov8856.c | 40 ----------------------------------------
1 file changed, 40 deletions(-)

diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
index cf8384e09413..b5c7881383ca 100644
--- a/drivers/media/i2c/ov8856.c
+++ b/drivers/media/i2c/ov8856.c
@@ -1709,46 +1709,6 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
return -ENXIO;
}

- ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
- OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
- if (ret)
- return ret;
-
- ret = ov8856_write_reg(ov8856, OV8856_OTP_MODE_CTRL,
- OV8856_REG_VALUE_08BIT, OV8856_OTP_MODE_AUTO);
- if (ret) {
- dev_err(&client->dev, "failed to set otp mode");
- return ret;
- }
-
- ret = ov8856_write_reg(ov8856, OV8856_OTP_LOAD_CTRL,
- OV8856_REG_VALUE_08BIT,
- OV8856_OTP_LOAD_CTRL_ENABLE);
- if (ret) {
- dev_err(&client->dev, "failed to enable load control");
- return ret;
- }
-
- ret = ov8856_read_reg(ov8856, OV8856_MODULE_REVISION,
- OV8856_REG_VALUE_08BIT, &val);
- if (ret) {
- dev_err(&client->dev, "failed to read module revision");
- return ret;
- }
-
- dev_info(&client->dev, "OV8856 revision %x (%s) at address 0x%02x\n",
- val,
- val == OV8856_2A_MODULE ? "2A" :
- val == OV8856_1B_MODULE ? "1B" : "unknown revision",
- client->addr);
-
- ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
- OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
- if (ret) {
- dev_err(&client->dev, "failed to exit streaming mode");
- return ret;
- }
-
ov8856->identified = true;

return 0;

---
base-commit: 9fd6ba5420ba2b637d1ecc6de8613ec8b9c87e5a
change-id: 20230323-ov8856-otp-112f3cdc74b1

Best regards,
--
Ricardo Ribalda <ribalda@xxxxxxxxxxxx>