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| author | Akinobu Mita <akinobu.mita@gmail.com> | 2018-05-06 10:19:18 -0400 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2018-06-28 08:56:51 -0400 |
| commit | 0b964d183cbf3f95a062ad9f3eec87ffa2790558 (patch) | |
| tree | 4f76936f81b668b53aef8bf7065171ddec7f3b3c /drivers/media/i2c/ov772x.c | |
| parent | c3f3ba3e6f78ea2159fca284e18840c6b3c1bfb6 (diff) | |
| download | linux-0b964d183cbf3f95a062ad9f3eec87ffa2790558.tar.gz linux-0b964d183cbf3f95a062ad9f3eec87ffa2790558.tar.bz2 linux-0b964d183cbf3f95a062ad9f3eec87ffa2790558.zip | |
media: ov772x: allow i2c controllers without I2C_FUNC_PROTOCOL_MANGLING
The ov772x driver only works when the i2c controller have
I2C_FUNC_PROTOCOL_MANGLING. However, many i2c controller drivers don't
support it.
The reason that the ov772x requires I2C_FUNC_PROTOCOL_MANGLING is that
it doesn't support repeated starts.
This changes the reading ov772x register method so that it doesn't
require I2C_FUNC_PROTOCOL_MANGLING by calling two separated i2c messages.
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'drivers/media/i2c/ov772x.c')
| -rw-r--r-- | drivers/media/i2c/ov772x.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c index e2550708abc8..b6223bfc022b 100644 --- a/drivers/media/i2c/ov772x.c +++ b/drivers/media/i2c/ov772x.c @@ -542,9 +542,19 @@ static struct ov772x_priv *to_ov772x(struct v4l2_subdev *sd) return container_of(sd, struct ov772x_priv, subdev); } -static inline int ov772x_read(struct i2c_client *client, u8 addr) +static int ov772x_read(struct i2c_client *client, u8 addr) { - return i2c_smbus_read_byte_data(client, addr); + int ret; + u8 val; + + ret = i2c_master_send(client, &addr, 1); + if (ret < 0) + return ret; + ret = i2c_master_recv(client, &val, 1); + if (ret < 0) + return ret; + + return val; } static inline int ov772x_write(struct i2c_client *client, u8 addr, u8 value) @@ -1255,13 +1265,11 @@ static int ov772x_probe(struct i2c_client *client, return -EINVAL; } - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | - I2C_FUNC_PROTOCOL_MANGLING)) { + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) { dev_err(&adapter->dev, - "I2C-Adapter doesn't support SMBUS_BYTE_DATA or PROTOCOL_MANGLING\n"); + "I2C-Adapter doesn't support SMBUS_BYTE_DATA\n"); return -EIO; } - client->flags |= I2C_CLIENT_SCCB; priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); if (!priv) |