[PATCH] x86, olpc: Wait for last byte of EC command to be accepted

From: Daniel Drake
Date: Tue Jul 26 2011 - 11:42:44 EST


From: Paul Fox <pgf@xxxxxxxxxx>

When executing EC commands, only waiting when there are still more bytes to
write is usually fine. However, if the system suspends very quickly after
a call to olpc_ec_cmd(), the last data byte may not yet be transferred to
the EC, and the command will not complete.

This solves a bug where the SCI wakeup mask was not correctly written
when going into suspend.

Signed-off-by: Paul Fox <pgf@xxxxxxxxxx>
Signed-off-by: Daniel Drake <dsd@xxxxxxxxxx>
---
arch/x86/platform/olpc/olpc.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
index 8b9940e..7cce722 100644
--- a/arch/x86/platform/olpc/olpc.c
+++ b/arch/x86/platform/olpc/olpc.c
@@ -161,13 +161,13 @@ restart:
if (inbuf && inlen) {
/* write data to EC */
for (i = 0; i < inlen; i++) {
+ pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]);
+ outb(inbuf[i], 0x68);
if (wait_on_ibf(0x6c, 0)) {
printk(KERN_ERR "olpc-ec: timeout waiting for"
" EC accept data!\n");
goto err;
}
- pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]);
- outb(inbuf[i], 0x68);
}
}
if (outbuf && outlen) {
--
1.7.6

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