Re: [PATCH] applesmc: Bump max wait and rearrange udelay

From: Parag Warudkar
Date: Mon Sep 17 2012 - 14:22:25 EST




On Mon, 17 Sep 2012, Henrik Rydberg wrote:

> The MBP10,1 experiences a lot of write errors with this patch.

I just noticed a single write failure - are you seeing something similar?

[ 1660.362997] applesmc: send_byte(0x00, 0x0300) fail: 0x00
[ 1660.363002] applesmc: LKSB: write data fail

Since the write fails are confirmed, I've locally dropped the send_byte
changes and just kept the wait_read ones that haven't caused me any
trouble yet.

Signed-off-by: Parag Warudkar <parag.lkml@xxxxxxxxx>

diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
index 2827088..2ba298a 100644
--- a/drivers/hwmon/applesmc.c
+++ b/drivers/hwmon/applesmc.c
@@ -169,14 +169,14 @@ static int wait_read(void)
{
u8 status;
int us;
- for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
- udelay(us);
+ for (us = APPLESMC_MIN_WAIT; us <= APPLESMC_MAX_WAIT; us <<= 1) {
status = inb(APPLESMC_CMD_PORT);
/* read: wait for smc to settle */
if (status & 0x01)
return 0;
+ if (us < APPLESMC_MAX_WAIT)
+ usleep_range(us, us << 1);
}
-
pr_warn("wait_read() fail: 0x%02x\n", status);
return -EIO;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/