V4L/DVB (6027): Get rid of an ill-behaved msleep in i2c write
Configuring the OLPC camera requires something over 150 register
writes. Unfortunately, querying the CAFE i2c controller too
soon after a write causes the hardware to flake. The problem had
been "solved" with an msleep() call, but, between the number of
registers and how msleep() behaves, that resulted in a 3-second
delay on camera initialization. Instead, we hand-code a wait for
the completion interrupt which avoids reading the status registers.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
index f8f21dd..c4c5bd6 100644
--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -416,7 +416,10 @@
static int ov7670_write(struct i2c_client *c, unsigned char reg,
unsigned char value)
{
- return i2c_smbus_write_byte_data(c, reg, value);
+ int ret = i2c_smbus_write_byte_data(c, reg, value);
+ if (reg == REG_COM7 && (value & COM7_RESET))
+ msleep(2); /* Wait for reset to run */
+ return ret;
}