@@ -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
*/
This is a note to let you know that I have just added a patch titled i2c: rcar: fix MNR interrupt handling to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.8. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 27d1ba1a2083fe64b0aa2482a72a1539d5f34b95 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Date: Tue, 2 Sep 2014 01:15:26 +0400 Subject: i2c: rcar: fix MNR interrupt handling 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 <sergei.shtylyov@cogentembedded.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> [ kamal: backport to 3.13-stable: context ] Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/i2c/busses/i2c-rcar.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) -- 1.9.1