From 8de531b03271169458d5aad66934d097056f0d0c Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Thu, 26 Dec 2013 23:07:22 -0300 Subject: [PATCH] [media] tvp5150: make read operations atomic MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Instead of using two I2C operations between write and read, use just one i2c_transfer. That allows I2C mutexes to not let any other I2C transfer between the two. Reviewed-by: Frank Schäfer Tested-by: Frank Schäfer Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/tvp5150.c | 24 ++++++++++-------------- 1 file changed, 10 insertions(+), 14 deletions(-) diff --git a/drivers/media/i2c/tvp5150.c b/drivers/media/i2c/tvp5150.c index 89c0b13463b7..2ed05b67218b 100644 --- a/drivers/media/i2c/tvp5150.c +++ b/drivers/media/i2c/tvp5150.c @@ -58,21 +58,17 @@ static int tvp5150_read(struct v4l2_subdev *sd, unsigned char addr) struct i2c_client *c = v4l2_get_subdevdata(sd); unsigned char buffer[1]; int rc; + struct i2c_msg msg[] = { + { .addr = c->addr, .flags = 0, + .buf = &addr, .len = 1 }, + { .addr = c->addr, .flags = I2C_M_RD, + .buf = buffer, .len = 1 } + }; - buffer[0] = addr; - - rc = i2c_master_send(c, buffer, 1); - if (rc < 0) { - v4l2_err(sd, "i2c i/o error: rc == %d (should be 1)\n", rc); - return rc; - } - - msleep(10); - - rc = i2c_master_recv(c, buffer, 1); - if (rc < 0) { - v4l2_err(sd, "i2c i/o error: rc == %d (should be 1)\n", rc); - return rc; + rc = i2c_transfer(c->adapter, msg, 2); + if (rc < 0 || rc != 2) { + v4l2_err(sd, "i2c i/o error: rc == %d (should be 2)\n", rc); + return rc < 0 ? rc : -EIO; } v4l2_dbg(2, debug, sd, "tvp5150: read 0x%02x = 0x%02x\n", addr, buffer[0]);