diff options
| author |   Alessandro Radicati <alessandro@radicati.net> | 2016-05-12 07:47:12 -0300 |
|---|---|---|
| committer |   Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2016-06-09 08:46:00 -0300 |
| commit | 1882f59f93066cb4ae922d68526bd0f33d2277cb (patch) | |
| tree | acfa3e3d2286e6cce9c312d73d7960f14d589709 /drivers/media/usb | |
| parent | [media] af9035: I2C combined write + read transaction fix (diff) | |
| download | linux-dev-1882f59f93066cb4ae922d68526bd0f33d2277cb.tar.xz linux-dev-1882f59f93066cb4ae922d68526bd0f33d2277cb.zip | |
[media] af9035: fix for MXL5007T devices with I2C read issues
The MXL5007T tuner will lock-up on some devices after an I2C read
transaction. This patch works around this issue by inhibiting such
operations and emulating a 0x00 response. The workaround is only
applied to USB devices known to exhibit this flaw.
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>
Diffstat (limited to 'drivers/media/usb')
| -rw-r--r-- | drivers/media/usb/dvb-usb-v2/af9035.c | 21 | ||||
| -rw-r--r-- | drivers/media/usb/dvb-usb-v2/af9035.h | 1 |
2 files changed, 22 insertions, 0 deletions
diff --git a/drivers/media/usb/dvb-usb-v2/af9035.c b/drivers/media/usb/dvb-usb-v2/af9035.c index 09a549b49400..a8ab592bf761 100644 --- a/drivers/media/usb/dvb-usb-v2/af9035.c +++ b/drivers/media/usb/dvb-usb-v2/af9035.c @@ -348,6 +348,9 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap, ret = af9035_rd_regs(d, reg, &msg[1].buf[0], msg[1].len); + } else if (state->no_read) { + memset(msg[1].buf, 0, msg[1].len); + ret = 0; } else { /* I2C write + read */ u8 buf[MAX_XFER_SIZE]; @@ -436,6 +439,9 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap, if (msg[0].len > 40) { /* TODO: correct limits > 40 */ ret = -EOPNOTSUPP; + } else if (state->no_read) { + memset(msg[0].buf, 0, msg[0].len); + ret = 0; } else { /* I2C read */ u8 buf[5]; @@ -977,6 +983,21 @@ skip_eeprom: state->af9033_config[i].clock = clock_lut_af9035[tmp]; } + state->no_read = false; + /* Some MXL5007T devices cannot properly handle tuner I2C read ops. */ + if (state->af9033_config[0].tuner == AF9033_TUNER_MXL5007T && + le16_to_cpu(d->udev->descriptor.idVendor) == USB_VID_AVERMEDIA) + + switch (le16_to_cpu(d->udev->descriptor.idProduct)) { + case USB_PID_AVERMEDIA_A867: + case USB_PID_AVERMEDIA_TWINSTAR: + dev_info(&d->udev->dev, + "%s: Device may have issues with I2C read operations. Enabling fix.\n", + KBUILD_MODNAME); + state->no_read = true; + break; + } + return 0; err: diff --git a/drivers/media/usb/dvb-usb-v2/af9035.h b/drivers/media/usb/dvb-usb-v2/af9035.h index 89e629a24aec..c91d1a3789e6 100644 --- a/drivers/media/usb/dvb-usb-v2/af9035.h +++ b/drivers/media/usb/dvb-usb-v2/af9035.h @@ -62,6 +62,7 @@ struct state { u8 chip_version; u16 chip_type; u8 dual_mode:1; + u8 no_read:1; u16 eeprom_addr; u8 af9033_i2c_addr[2]; struct af9033_config af9033_config[2]; |