From 9eb13cf3ecf67a0ff3114d6b66878a1149f96b7d Mon Sep 17 00:00:00 2001
From: Aaro Koskinen <aaro.koskinen@iki.fi>
Date: Sun, 20 Jan 2013 20:37:02 +0200
Subject: [PATCH] i2c: omap: fix draining irq handling
Commit 0bdfe0cb803dce699ff337c35d8e97ac355fa417 (i2c: omap: sanitize
exit path) changed the interrupt handler to exit early and complete
the transfer after the draining IRQ is handled. As a result, the ARDY
may not be cleared properly, and it may cause all future I2C transfers
to timeout with "timeout waiting for bus ready". This is reproducible
at least with N900 when twl4030_gpio makes a long write (> FIFO size)
during the probe (http://marc.info/?l=linux-omap&m=135818882610432&w=2).
The fix is to continue until we get ARDY interrupt that completes the
transfer. Tested with 3.8-rc4 + N900: 20 boots in a row without errors;
without the patch the problem triggers after few reboots.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
---
drivers/i2c/busses/i2c-omap.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 832f16e19f446e..4cc2f0528c8869 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -963,7 +963,7 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
i2c_omap_errata_i207(dev, stat);
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
- break;
+ continue;
}
if (stat & OMAP_I2C_STAT_RRDY) {
@@ -989,7 +989,7 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
break;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
- break;
+ continue;
}
if (stat & OMAP_I2C_STAT_XRDY) {
--
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