From 0f7acb52911066b4e2de93879b2089aea37aeb08 Mon Sep 17 00:00:00 2001 From: Hugues Fruchet Date: Wed, 3 Jan 2018 04:57:29 -0500 Subject: [PATCH] media: ov5640: check chip id Verify that chip identifier is correct when probing. Signed-off-by: Hugues Fruchet Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/ov5640.c | 95 ++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 79 insertions(+), 16 deletions(-) diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c index 61071f52a881..9f031f3a3708 100644 --- a/drivers/media/i2c/ov5640.c +++ b/drivers/media/i2c/ov5640.c @@ -1547,24 +1547,58 @@ static void ov5640_reset(struct ov5640_dev *sensor) usleep_range(5000, 10000); } -static int ov5640_set_power(struct ov5640_dev *sensor, bool on) +static int ov5640_set_power_on(struct ov5640_dev *sensor) { - int ret = 0; + struct i2c_client *client = sensor->i2c_client; + int ret; - if (on) { - clk_prepare_enable(sensor->xclk); + ret = clk_prepare_enable(sensor->xclk); + if (ret) { + dev_err(&client->dev, "%s: failed to enable clock\n", + __func__); + return ret; + } - ret = regulator_bulk_enable(OV5640_NUM_SUPPLIES, - sensor->supplies); - if (ret) - goto xclk_off; + ret = regulator_bulk_enable(OV5640_NUM_SUPPLIES, + sensor->supplies); + if (ret) { + dev_err(&client->dev, "%s: failed to enable regulators\n", + __func__); + goto xclk_off; + } + + ov5640_reset(sensor); + ov5640_power(sensor, true); + + ret = ov5640_init_slave_id(sensor); + if (ret) + goto power_off; + + return 0; + +power_off: + ov5640_power(sensor, false); + regulator_bulk_disable(OV5640_NUM_SUPPLIES, sensor->supplies); +xclk_off: + clk_disable_unprepare(sensor->xclk); + return ret; +} + +static void ov5640_set_power_off(struct ov5640_dev *sensor) +{ + ov5640_power(sensor, false); + regulator_bulk_disable(OV5640_NUM_SUPPLIES, sensor->supplies); + clk_disable_unprepare(sensor->xclk); +} - ov5640_reset(sensor); - ov5640_power(sensor, true); +static int ov5640_set_power(struct ov5640_dev *sensor, bool on) +{ + int ret = 0; - ret = ov5640_init_slave_id(sensor); + if (on) { + ret = ov5640_set_power_on(sensor); if (ret) - goto power_off; + return ret; ret = ov5640_restore_mode(sensor); if (ret) @@ -1586,10 +1620,7 @@ static int ov5640_set_power(struct ov5640_dev *sensor, bool on) } power_off: - ov5640_power(sensor, false); - regulator_bulk_disable(OV5640_NUM_SUPPLIES, sensor->supplies); -xclk_off: - clk_disable_unprepare(sensor->xclk); + ov5640_set_power_off(sensor); return ret; } @@ -2202,6 +2233,34 @@ static int ov5640_get_regulators(struct ov5640_dev *sensor) sensor->supplies); } +static int ov5640_check_chip_id(struct ov5640_dev *sensor) +{ + struct i2c_client *client = sensor->i2c_client; + int ret = 0; + u16 chip_id; + + ret = ov5640_set_power_on(sensor); + if (ret) + return ret; + + ret = ov5640_read_reg16(sensor, OV5640_REG_CHIP_ID, &chip_id); + if (ret) { + dev_err(&client->dev, "%s: failed to read chip identifier\n", + __func__); + goto power_off; + } + + if (chip_id != 0x5640) { + dev_err(&client->dev, "%s: wrong chip identifier, expected 0x5640, got 0x%x\n", + __func__, chip_id); + ret = -ENXIO; + } + +power_off: + ov5640_set_power_off(sensor); + return ret; +} + static int ov5640_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -2284,6 +2343,10 @@ static int ov5640_probe(struct i2c_client *client, mutex_init(&sensor->lock); + ret = ov5640_check_chip_id(sensor); + if (ret) + goto entity_cleanup; + ret = ov5640_init_controls(sensor); if (ret) goto entity_cleanup; -- 2.11.0