saa7134: fix warm Medion 7134 EEPROM read
commit 5a91206ff0d0548939f3e85a65fb76b400fb0e89 upstream.
When saa7134 module driving a Medion 7134 card is reloaded reads of this
card EEPROM (required for automatic detection of tuner model) will be
corrupted due to I2C gate in DVB-T demod being left closed.
This sometimes also happens on first saa7134 module load after a warm
reboot.
Fix this by opening this I2C gate before doing EEPROM read during i2c
initialization.
Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/media/pci/saa7134/saa7134-i2c.c b/drivers/media/pci/saa7134/saa7134-i2c.c
index 8ef6399..bc95752 100644
--- a/drivers/media/pci/saa7134/saa7134-i2c.c
+++ b/drivers/media/pci/saa7134/saa7134-i2c.c
@@ -355,12 +355,43 @@
/* ----------------------------------------------------------- */
+/* On Medion 7134 reading EEPROM needs DVB-T demod i2c gate open */
+static void saa7134_i2c_eeprom_md7134_gate(struct saa7134_dev *dev)
+{
+ u8 subaddr = 0x7, dmdregval;
+ u8 data[2];
+ int ret;
+ struct i2c_msg i2cgatemsg_r[] = { {.addr = 0x08, .flags = 0,
+ .buf = &subaddr, .len = 1},
+ {.addr = 0x08,
+ .flags = I2C_M_RD,
+ .buf = &dmdregval, .len = 1}
+ };
+ struct i2c_msg i2cgatemsg_w[] = { {.addr = 0x08, .flags = 0,
+ .buf = data, .len = 2} };
+
+ ret = i2c_transfer(&dev->i2c_adap, i2cgatemsg_r, 2);
+ if ((ret == 2) && (dmdregval & 0x2)) {
+ pr_debug("%s: DVB-T demod i2c gate was left closed\n",
+ dev->name);
+
+ data[0] = subaddr;
+ data[1] = (dmdregval & ~0x2);
+ if (i2c_transfer(&dev->i2c_adap, i2cgatemsg_w, 1) != 1)
+ pr_err("%s: EEPROM i2c gate open failure\n",
+ dev->name);
+ }
+}
+
static int
saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
{
unsigned char buf;
int i,err;
+ if (dev->board == SAA7134_BOARD_MD7134)
+ saa7134_i2c_eeprom_md7134_gate(dev);
+
dev->i2c_client.addr = 0xa0 >> 1;
buf = 0;
if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
