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author | Jacopo Mondi <jacopo@jmondi.org> | 2017-05-12 15:36:59 +0300 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2017-06-23 14:28:05 +0300 |
commit | ab924af9acde26a5840b905c599dd4f3e10eaa00 (patch) | |
tree | 8a3746134d92e53f9c7a75e7af9bcd415fb1d339 | |
parent | affd250dec1717e225fa2015ad6b238a43d5aca5 (diff) | |
download | linux-ab924af9acde26a5840b905c599dd4f3e10eaa00.tar.xz |
[media] media: i2c: ov772x: Force use of SCCB protocol
Commit e78902976150 ("i2c: sh_mobile: don't send a stop condition by
default inside transfers") makes the i2c_sh_mobile I2C-adapter emit a
stop/start sequence between messages in a single transfer only when
explicitly requested with I2C_M_STOP.
This breaks the ov772x driver in the SH4 Migo-R board as the Omnivision
sensor uses the I2C-like SCCB protocol that doesn't support repeated
starts:
i2c-sh_mobile i2c-sh_mobile.0: Transfer request timed out
ov772x 0-0021: Product ID error 92:92
Fix it by marking the client as SCCB, forcing the emission of a
stop/start sequence between all messages.
As I2C_M_STOP requires the I2C adapter to support protocol mangling,
ensure that the I2C_FUNC_PROTOCOL_MANGLING functionality is available.
Tested on SH4 Migo-R board, with OV772x now successfully probing
soc-camera-pdrv soc-camera-pdrv.0: Probing soc-camera-pdrv.0
ov772x 0-0021: ov7725 Product ID 77:21 Manufacturer ID 7f:a2
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
-rw-r--r-- | drivers/media/i2c/soc_camera/ov772x.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/media/i2c/soc_camera/ov772x.c b/drivers/media/i2c/soc_camera/ov772x.c index 0f7b9d1b9c57..806383500313 100644 --- a/drivers/media/i2c/soc_camera/ov772x.c +++ b/drivers/media/i2c/soc_camera/ov772x.c @@ -1047,11 +1047,13 @@ static int ov772x_probe(struct i2c_client *client, return -EINVAL; } - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) { + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_PROTOCOL_MANGLING)) { dev_err(&adapter->dev, - "I2C-Adapter doesn't support I2C_FUNC_SMBUS_BYTE_DATA\n"); + "I2C-Adapter doesn't support SMBUS_BYTE_DATA or PROTOCOL_MANGLING\n"); return -EIO; } + client->flags |= I2C_CLIENT_SCCB; priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); if (!priv) |