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

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>

diff --git a/drivers/media/video/cx23885/cx23885-i2c.c b/drivers/media/video/cx23885/cx23885-i2c.c
index 4172cb3874207428556d5d75e99d46e1d5f6a38f..d4746e06451692f8c853bf8c73924c87f6ad70b3 100644 (file)
--- 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_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;

diff --git a/drivers/media/video/cx88/cx88-i2c.c b/drivers/media/video/cx88/cx88-i2c.c
index ee1ca39db06ad684758dc4da0bfa8b35aa8e1f56..fb39f11845583a86dcb463745d66d498bc873efe 100644 (file)
--- 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, 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;
 }