From 57f1c0533850c0d68d114353b3b3a61148498698 Mon Sep 17 00:00:00 2001
From: Alessandro Radicati <alessandro@radicati.net>
Date: Tue, 5 Apr 2016 19:23:43 -0300
Subject: [PATCH] [media] af9035: I2C combined write + read transaction fix
This patch will modify the af9035 driver to use the register address
fields of the I2C read command for the combined write/read transaction
case. Without this change, the firmware issues just a I2C read
transaction without the preceding write transaction to select the
register.
Signed-off-by: Alessandro Radicati <alessandro@radicati.net>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
---
drivers/media/usb/dvb-usb-v2/af9035.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/drivers/media/usb/dvb-usb-v2/af9035.c b/drivers/media/usb/dvb-usb-v2/af9035.c
index 2638e3251f2a1..09a549b494003 100644
--- a/drivers/media/usb/dvb-usb-v2/af9035.c
+++ b/drivers/media/usb/dvb-usb-v2/af9035.c
@@ -367,10 +367,25 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap,
memcpy(&buf[3], msg[0].buf, msg[0].len);
} else {
buf[1] = msg[0].addr << 1;
- buf[2] = 0x00; /* reg addr len */
buf[3] = 0x00; /* reg addr MSB */
buf[4] = 0x00; /* reg addr LSB */
- memcpy(&buf[5], msg[0].buf, msg[0].len);
+
+ /* Keep prev behavior for write req len > 2*/
+ if (msg[0].len > 2) {
+ buf[2] = 0x00; /* reg addr len */
+ memcpy(&buf[5], msg[0].buf, msg[0].len);
+
+ /* Use reg addr fields if write req len <= 2 */
+ } else {
+ req.wlen = 5;
+ buf[2] = msg[0].len;
+ if (msg[0].len == 2) {
+ buf[3] = msg[0].buf[0];
+ buf[4] = msg[0].buf[1];
+ } else if (msg[0].len == 1) {
+ buf[4] = msg[0].buf[0];
+ }
+ }
}
ret = af9035_ctrl_msg(d, &req);
}
--
2.39.5