From 96b5b11aeb6ac859d4a8603a82a35d9250ea460d Mon Sep 17 00:00:00 2001 From: Robert Foss Date: Mon, 11 May 2020 13:03:50 +0200 Subject: [PATCH] media: ov8856: Implement sensor module revision identification Query the sensor for its module revision, and compare it to known revisions. Currently 2A and 1B revision indentification is supported. [Sakari Ailus: Wrap a line over 80, alignment, use %u for printing u32] Signed-off-by: Robert Foss Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/ov8856.c | 53 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c index efc3e231c9b7..4ca27675cc5a 100644 --- a/drivers/media/i2c/ov8856.c +++ b/drivers/media/i2c/ov8856.c @@ -32,6 +32,19 @@ #define OV8856_MODE_STANDBY 0x00 #define OV8856_MODE_STREAMING 0x01 +/* module revisions */ +#define OV8856_2A_MODULE 0x01 +#define OV8856_1B_MODULE 0x02 + +/* the OTP read-out buffer is at 0x7000 and 0xf is the offset + * of the byte in the OTP that means the module revision + */ +#define OV8856_MODULE_REVISION 0x700f +#define OV8856_OTP_MODE_CTRL 0x3d84 +#define OV8856_OTP_LOAD_CTRL 0x3d81 +#define OV8856_OTP_MODE_AUTO 0x00 +#define OV8856_OTP_LOAD_CTRL_ENABLE BIT(0) + /* vertical-timings from sensor */ #define OV8856_REG_VTS 0x380e #define OV8856_VTS_MAX 0x7fff @@ -1156,6 +1169,46 @@ 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; + } + return 0; }