[PATCH] therm_adt746x: Don't access non-existing register

[PATCH] therm_adt746x: Don't access non-existing register

[Jean Delvare]

The ADT746x don't have any register at sub-address 0, so better use an
existing register for the initial test read.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Colin Leroy <colin@colino.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
---
Tim, I don't really expect this to solve your problem, but who knows...
Care to give it a try, just in case?

 drivers/macintosh/therm_adt746x.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- linux-2.6.32-rc4.orig/drivers/macintosh/therm_adt746x.c	2009-10-12 11:53:59.000000000 +0200
+++ linux-2.6.32-rc4/drivers/macintosh/therm_adt746x.c	2009-10-14 17:27:46.000000000 +0200
@@ -387,7 +387,7 @@ static int probe_thermostat(struct i2c_c
 	i2c_set_clientdata(client, th);
 	th->clt = client;
 
-	rc = read_reg(th, 0);
+	rc = read_reg(th, CONFIG_REG);
 	if (rc < 0) {
 		dev_err(&client->dev, "Thermostat failed to read config!\n");
 		kfree(th);


-- 
Jean Delvare

Re: [PATCH] therm_adt746x: Don't access non-existing register

[Tim Shepard]

Jean,

I tried one reboot with your patch, failed as usual.
(Patch sounds like a good idea though.)

			-Tim Shepard
			 shep@alum.mit.edu



tree<11>$ git describe
v2.6.31.1-6-g0b193bc
tree<12>$ git diff HEAD^ HEAD
diff --git a/drivers/macintosh/therm_adt746x.c b/drivers/macintosh/therm_adt746x.c
index 0554dae..bf9ed2d 100644
--- a/drivers/macintosh/therm_adt746x.c
+++ b/drivers/macintosh/therm_adt746x.c
@@ -366,7 +366,7 @@ static int probe_thermostat(struct i2c_client *client,
        i2c_set_clientdata(client, th);
        th->clt = client;
 
-       rc = read_reg(th, 0);
+       rc = read_reg(th, CONFIG_REG);
        if (rc < 0) {
                dev_err(&client->dev, "Thermostat failed to read config!\n");
                kfree(th);
tree<13>$ dmesg | head
Using PowerMac machine description
Total memory = 1536MB; using 4096kB for hash table (at cfc00000)
Linux version 2.6.31.1-00006-g0b193bc (shep@tree) (gcc version 4.3.2 (Debian 4.3.2-1.1) ) #9 Wed Oct 14 13:41:40 EDT 2009
Found UniNorth memory controller & host bridge @ 0xf8000000 revision: 0xd9
Mapped at 0xff7c0000
Found a Intrepid mac-io controller, rev: 0, mapped at 0xff740000
Processor NAP mode on idle enabled.
PowerMac motherboard: PowerBook G4 15"
console [udbg0] enabled
Found UniNorth PCI host bridge at 0x00000000f0000000. Firmware bus number: 0->1
tree<14>$ dmesg | grep adt
adt746x: version 1 (supported)
adt746x: Thermostat bus: 0, address: 0x2e, limit_adjust: 0, fan_speed: -1
therm_adt746x 7-002e: Thermostat failed to read config!
tree<15>$