3.13.11.8 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Sergei Shtylyov <[email protected]> commit dd318b0df27c582ac0d72a346fd6e693700be23c upstream. Sometimes the MNR and MST interrupts happen simultaneously (stop automatically follows NACK, according to the manuals) and in such case the ID_NACK flag isn't set since the MST interrupt handling precedes MNR and all interrupts are cleared and disabled then, so that MNR interrupt is never noticed -- this causes NACK'ed transfers to be falsely reported as successful. Exchanging MNR and MST handlers fixes this issue, however the MNR bit somehow gets set again even after being explicitly cleared, so I decided to completely suppress handling of all disabled interrupts (which is a good thing anyway)... Signed-off-by: Sergei Shtylyov <[email protected]> Signed-off-by: Wolfram Sang <[email protected]> [ kamal: backport to 3.13-stable: context ] Signed-off-by: Kamal Mostafa <[email protected]> --- drivers/i2c/busses/i2c-rcar.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 56de337..e64bb5b 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -488,6 +488,9 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr) msr = rcar_i2c_status_get(priv); + /* Only handle interrupts that are currently enabled */ + msr &= rcar_i2c_read(priv, ICMIER); + /* * Arbitration lost */ @@ -503,15 +506,6 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr) } /* - * Stop - */ - if (msr & MST) { - dev_dbg(dev, "Stop\n"); - rcar_i2c_flags_set(priv, ID_DONE); - goto out; - } - - /* * Nack */ if (msr & MNR) { @@ -524,6 +518,12 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr) goto out; } + /* Stop */ + if (msr & MST) { + rcar_i2c_flags_set(priv, ID_DONE); + goto out; + } + /* * recv/send */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
