i2c: omap: Clear ARDY bit twice
authorTaras Kondratiuk <taras.kondratiuk@linaro.org>
Mon, 7 Oct 2013 10:41:59 +0000 (13:41 +0300)
committerWolfram Sang <wsa@the-dreams.de>
Thu, 10 Oct 2013 08:22:32 +0000 (10:22 +0200)
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@ti.com>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
drivers/i2c/busses/i2c-omap.c

index 6d8308d5dc4e915c4584e2d5d9b3e5690882a2b9..9967a6f9c2ffba2fe4521a8abf19b49e978110a4 100644 (file)
@@ -939,6 +939,9 @@ 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);
+
                if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
                                        OMAP_I2C_STAT_AL)) {
                        omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |