From 5ff5059b4b65352df22872bb8697026fe68f13f7 Mon Sep 17 00:00:00 2001 From: Taras Kondratiuk Date: Mon, 7 Oct 2013 13:41:59 +0300 Subject: [PATCH] i2c: omap: Clear ARDY bit twice Initially commit 229debedf7246a5ca66aa8dd91520b5b2fb19a97 "i2c-omap: Double clear of ARDY status in IRQ handler" added a workaround for undocumented errata ProDB0017052. But then commit 415ed4be9824470d8f687e8cd8fc160b69abb26b "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 Signed-off-by: Taras Kondratiuk Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- 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 6d8308d5dc4e9..9967a6f9c2ffb 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -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 | -- 2.39.5