[PATCH 3.8 13/81] i2c: omap: Clear ARDY bit twice

From: Kamal Mostafa
Date: Tue Oct 29 2013 - 14:24:31 EST -stable review patch. If anyone has any objections, please let me know.


From: Taras Kondratiuk <taras.kondratiuk@xxxxxxxxxx>

commit 4cdbf7d346e7461c3b93a26707c852e2c9db3753 upstream.

Initially commit cb527ede1bf6ff2008a025606f25344b8ed7b4ac
"i2c-omap: Double clear of ARDY status in IRQ handler"
added a workaround for undocumented errata ProDB0017052.
But then commit 1d7afc95946487945cc7f5019b41255b72224b70
"i2c: omap: ack IRQ in parts" refactored code and missed
one of ARDY clearings. So current code violates errata.
It causes often i2c bus timeouts on my Pandaboard.

This patch adds a second clearing in place.

Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@xxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
drivers/i2c/busses/i2c-omap.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 4cc2f05..6fc54cd 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -941,6 +941,9 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
* ProDB0017052: Clear ARDY bit twice
+ if (stat & OMAP_I2C_STAT_ARDY)
+ omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ARDY);
omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |

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