[34-longterm 229/260] x86, olpc: Don't retry EC commands forever

From: Paul Gortmaker
Date: Sun Jan 02 2011 - 02:33:03 EST


From: Paul Fox <pgf@xxxxxxxxxx>

commit 286e5b97eb22baab9d9a41ca76c6b933a484252c upstream.

Avoids a potential infinite loop.

It was observed once, during an EC hacking/debugging
session - not in regular operation.

Signed-off-by: Daniel Drake <dsd@xxxxxxxxxx>
Cc: dilinger@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
arch/x86/kernel/olpc.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/olpc.c b/arch/x86/kernel/olpc.c
index 8297160..a23b382 100644
--- a/arch/x86/kernel/olpc.c
+++ b/arch/x86/kernel/olpc.c
@@ -117,6 +117,7 @@ int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen,
unsigned long flags;
int ret = -EIO;
int i;
+ int restarts = 0;

spin_lock_irqsave(&ec_lock, flags);

@@ -173,7 +174,9 @@ restart:
if (wait_on_obf(0x6c, 1)) {
printk(KERN_ERR "olpc-ec: timeout waiting for"
" EC to provide data!\n");
- goto restart;
+ if (restarts++ < 10)
+ goto restart;
+ goto err;
}
outbuf[i] = inb(0x68);
printk(KERN_DEBUG "olpc-ec: received 0x%x\n",
--
1.7.3.3

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