V4L/DVB (9585): Skip reading eeprom in newer Empia devices
Empia switched to a 16-bit addressable eeprom in newer devices. While we
could certainly write a routine to read the eeprom, there is nothing of use
in there that cannot be accessed through registers, and there is the risk that
we could corrupt the eeprom (since a 16-bit read call is interpreted as a
write call by 8-bit eeproms). So just be safe and bail out of the function.
Thanks for Ray Lu from Empia for providing the em2874 datasheet.
Signed-off-by: Devin Heitmueller <devin.heitmueller@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/em28xx/em28xx-i2c.c b/drivers/media/video/em28xx/em28xx-i2c.c
index 2360c61..ec3e3b1 100644
--- a/drivers/media/video/em28xx/em28xx-i2c.c
+++ b/drivers/media/video/em28xx/em28xx-i2c.c
@@ -332,6 +332,17 @@
struct em28xx_eeprom *em_eeprom = (void *)eedata;
int i, err, size = len, block;
+ if (dev->chip_id == CHIP_ID_EM2874) {
+ /* Empia switched to a 16-bit addressable eeprom in newer
+ devices. While we could certainly write a routine to read
+ the eeprom, there is nothing of use in there that cannot be
+ accessed through registers, and there is the risk that we
+ could corrupt the eeprom (since a 16-bit read call is
+ interpreted as a write call by 8-bit eeproms).
+ */
+ return 0;
+ }
+
dev->i2c_client.addr = 0xa0 >> 1;
/* Check if board has eeprom */