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V4L/DVB: FusionHDTV: Use quick reads for I2C IR device probing

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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>
This commit is contained in:
Jean Delvare 2010-05-26 10:05:11 -03:00 committed by Mauro Carvalho Chehab
parent f137f9d000
commit 806b07c29b
2 changed files with 26 additions and 2 deletions
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12
drivers/media/video/cx23885/cx23885-i2c.c
View file

@ -365,7 +365,17 @@ int cx23885_i2c_register(struct cx23885_i2c *bus)
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;

16
drivers/media/video/cx88/cx88-i2c.c
View file

@ -188,10 +188,24 @@ int cx88_i2c_init(struct cx88_core *core, struct pci_dev *pci)
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;
}