aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch
diff options
context:
space:
mode:
authorRussell King <linux@armlinux.org.uk>2020-05-21 09:57:27 +0100
committerPetr Štetiar <ynezz@true.cz>2020-05-21 12:55:31 +0200
commit714199ec3461b2b5bac9796d4f5ee79f56d2eb00 (patch)
tree9d02420e261024062d56df1b12776d9594c38658 /target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch
parent72a1d5c3acd5b0bec46612f94bb8a82fe4d56179 (diff)
downloadupstream-714199ec3461b2b5bac9796d4f5ee79f56d2eb00.tar.gz
upstream-714199ec3461b2b5bac9796d4f5ee79f56d2eb00.tar.bz2
upstream-714199ec3461b2b5bac9796d4f5ee79f56d2eb00.zip
kernel: backport v5.8 i2c-pxa updates
Add i2c-pxa updates queued for v5.8, which add bus recovery to this driver; this is needed for the uDPU platform. Signed-off-by: Russell King <linux@armlinux.org.uk>
Diffstat (limited to 'target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch')
-rw-r--r--target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch43
1 files changed, 43 insertions, 0 deletions
diff --git a/target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch b/target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch
new file mode 100644
index 0000000000..997670716f
--- /dev/null
+++ b/target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch
@@ -0,0 +1,43 @@
+From: Russell King <rmk+kernel@armlinux.org.uk>
+Bcc: linux@mail.armlinux.org.uk
+Subject: [PATCH 5/7] i2c: pxa: clear all master action bits in
+ i2c_pxa_stop_message()
+MIME-Version: 1.0
+Content-Disposition: inline
+Content-Transfer-Encoding: 8bit
+Content-Type: text/plain; charset="utf-8"
+
+If we timeout during a message transfer, the control register may
+contain bits that cause an action to be set. Read-modify-writing the
+register leaving these bits set may trigger the hardware to attempt
+one of these actions unintentionally.
+
+Always clear these bits when cleaning up after a message or after
+a timeout.
+
+Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
+---
+ drivers/i2c/busses/i2c-pxa.c | 6 ++----
+ 1 file changed, 2 insertions(+), 4 deletions(-)
+
+diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
+index db739cce93ac..a72d07bdb793 100644
+--- a/drivers/i2c/busses/i2c-pxa.c
++++ b/drivers/i2c/busses/i2c-pxa.c
+@@ -795,11 +795,9 @@ static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
+ {
+ u32 icr;
+
+- /*
+- * Clear the STOP and ACK flags
+- */
++ /* Clear the START, STOP, ACK, TB and MA flags */
+ icr = readl(_ICR(i2c));
+- icr &= ~(ICR_STOP | ICR_ACKNAK);
++ icr &= ~(ICR_START | ICR_STOP | ICR_ACKNAK | ICR_TB | ICR_MA);
+ writel(icr, _ICR(i2c));
+ }
+
+--
+2.20.1
+