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| author | Patrick Boettcher <pboettcher@kernellabs.com> | 2009-11-30 14:14:36 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2009-12-16 00:18:27 -0200 |
| commit | 38ffcd10d6831efd15ec5a223b1050eac12d4c28 (patch) | |
| tree | 639c629cc9a79ea1b5ef2a16aa7804028a29139a | |
| parent | d995a18733a683c1c086a4d48315976f8c25d89b (diff) | |
| download | lwn-38ffcd10d6831efd15ec5a223b1050eac12d4c28.tar.gz lwn-38ffcd10d6831efd15ec5a223b1050eac12d4c28.zip | |
V4L/DVB (13581): DiBUSB: fix I2c access when there is a read-access w/o write sequence
This patch fixes the behaviour of the dibusb-i2c-access which was previously changed to avoid accidental EEprom writes:
Now it allow i2c-reads without prepended i2c-writes, but it is still not doing anything in case the EEprom is addressed.
Thanks to Mario Bachmann for testing.
Tested-by: Mario Bachmann <grafgrimm77@gmx.de>
Cc: Mario Bachmann <grafgrimm77@gmx.de>
Signed-off-by: Patrick Boettcher <pboettcher@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| -rw-r--r-- | drivers/media/dvb/dvb-usb/dibusb-common.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/media/dvb/dvb-usb/dibusb-common.c b/drivers/media/dvb/dvb-usb/dibusb-common.c index b395e852e47f..9143b5631e88 100644 --- a/drivers/media/dvb/dvb-usb/dibusb-common.c +++ b/drivers/media/dvb/dvb-usb/dibusb-common.c @@ -142,8 +142,13 @@ static int dibusb_i2c_xfer(struct i2c_adapter *adap,struct i2c_msg msg[],int num } else if ((msg[i].flags & I2C_M_RD) == 0) { if (dibusb_i2c_msg(d, msg[i].addr, msg[i].buf,msg[i].len,NULL,0) < 0) break; - } else - break; + } else if (msg[i].addr != 0x50) { + /* 0x50 is the address of the eeprom - we need to protect it + * from dibusb's bad i2c implementation: reads without + * writing the offset before are forbidden */ + if (dibusb_i2c_msg(d, msg[i].addr, NULL, 0, msg[i].buf, msg[i].len) < 0) + break; + } } mutex_unlock(&d->i2c_mutex); |