| From 806b07c29b711aaf90c81d2a19711607769f8246 Mon Sep 17 00:00:00 2001 |
| From: Jean Delvare <khali@linux-fr.org> |
| Date: Wed, 26 May 2010 10:05:11 -0300 |
| Subject: V4L/DVB: FusionHDTV: Use quick reads for I2C IR device probing |
| |
| From: Jean Delvare <khali@linux-fr.org> |
| |
| commit 806b07c29b711aaf90c81d2a19711607769f8246 upstream. |
| |
| IR support on FusionHDTV cards is broken since kernel 2.6.31. One side |
| effect of the switch to the standard binding model for IR I2C devices |
| was to let i2c-core do the probing instead of the ir-kbd-i2c driver. |
| There is a slight difference between the two probe methods: i2c-core |
| uses 0-byte writes, while the ir-kbd-i2c was using 0-byte reads. As |
| some IR I2C devices only support reads, the new probe method fails to |
| detect them. |
| |
| For now, revert to letting the driver do the probe, using 0-byte |
| reads. In the future, i2c-core will be extended to let callers of |
| i2c_new_probed_device() provide a custom probing function. |
| |
| Signed-off-by: Jean Delvare <khali@linux-fr.org> |
| Tested-by: "Timothy D. Lenz" <tlenz@vorgon.com> |
| Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| drivers/media/video/cx23885/cx23885-i2c.c | 12 +++++++++++- |
| drivers/media/video/cx88/cx88-i2c.c | 16 +++++++++++++++- |
| 2 files changed, 26 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/media/video/cx23885/cx23885-i2c.c |
| +++ b/drivers/media/video/cx23885/cx23885-i2c.c |
| @@ -365,7 +365,17 @@ int cx23885_i2c_register(struct cx23885_ |
| |
| memset(&info, 0, sizeof(struct i2c_board_info)); |
| strlcpy(info.type, "ir_video", I2C_NAME_SIZE); |
| - i2c_new_probed_device(&bus->i2c_adap, &info, addr_list); |
| + /* |
| + * We can't call i2c_new_probed_device() because it uses |
| + * quick writes for probing and the IR receiver device only |
| + * replies to reads. |
| + */ |
| + if (i2c_smbus_xfer(&bus->i2c_adap, addr_list[0], 0, |
| + I2C_SMBUS_READ, 0, I2C_SMBUS_QUICK, |
| + NULL) >= 0) { |
| + info.addr = addr_list[0]; |
| + i2c_new_device(&bus->i2c_adap, &info); |
| + } |
| } |
| |
| return bus->i2c_rc; |
| --- a/drivers/media/video/cx88/cx88-i2c.c |
| +++ b/drivers/media/video/cx88/cx88-i2c.c |
| @@ -188,10 +188,24 @@ int cx88_i2c_init(struct cx88_core *core |
| 0x18, 0x6b, 0x71, |
| I2C_CLIENT_END |
| }; |
| + const unsigned short *addrp; |
| |
| memset(&info, 0, sizeof(struct i2c_board_info)); |
| strlcpy(info.type, "ir_video", I2C_NAME_SIZE); |
| - i2c_new_probed_device(&core->i2c_adap, &info, addr_list); |
| + /* |
| + * We can't call i2c_new_probed_device() because it uses |
| + * quick writes for probing and at least some R receiver |
| + * devices only reply to reads. |
| + */ |
| + for (addrp = addr_list; *addrp != I2C_CLIENT_END; addrp++) { |
| + if (i2c_smbus_xfer(&core->i2c_adap, *addrp, 0, |
| + I2C_SMBUS_READ, 0, |
| + I2C_SMBUS_QUICK, NULL) >= 0) { |
| + info.addr = *addrp; |
| + i2c_new_device(&core->i2c_adap, &info); |
| + break; |
| + } |
| + } |
| } |
| return core->i2c_rc; |
| } |