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-rw-r--r--meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0029-i2c-mux-pca954x-fix-i2c-mux-selection-caching.patch51
-rw-r--r--meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas_4.9.bbappend1
2 files changed, 52 insertions, 0 deletions
diff --git a/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0029-i2c-mux-pca954x-fix-i2c-mux-selection-caching.patch b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0029-i2c-mux-pca954x-fix-i2c-mux-selection-caching.patch
new file mode 100644
index 0000000..1640b51
--- /dev/null
+++ b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0029-i2c-mux-pca954x-fix-i2c-mux-selection-caching.patch
@@ -0,0 +1,51 @@
+From 7f638c1cb0a1112dbe0b682a42db30521646686b Mon Sep 17 00:00:00 2001
+From: Russell King <rmk+kernel@armlinux.org.uk>
+Date: Sat, 17 Dec 2016 12:10:56 +0000
+Subject: [PATCH] i2c: mux: pca954x: fix i2c mux selection caching
+
+smbus functions return -ve on error, 0 on success. However,
+__i2c_transfer() have a different return signature - -ve on error, or
+number of buffers transferred (which may be zero or greater.)
+
+The upshot of this is that the sense of the test is reversed when using
+the mux on a bus supporting the master_xfer method: we cache the value
+and never retry if we fail to transfer any buffers, but if we succeed,
+we clear the cached value.
+
+Fix this by making pca954x_reg_write() return a negative error code for
+all failure cases.
+
+Fixes: 463e8f845cbf ("i2c: mux: pca954x: retry updating the mux selection on failure")
+Acked-by: Peter Rosin <peda@axentia.se>
+Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/muxes/i2c-mux-pca954x.c | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
+index 9a348ee..dd18b9c 100644
+--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
++++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
+@@ -167,6 +167,9 @@ static int pca954x_reg_write(struct i2c_adapter *adap,
+ buf[0] = val;
+ msg.buf = buf;
+ ret = __i2c_transfer(adap, &msg, 1);
++
++ if (ret >= 0 && ret != 1)
++ ret = -EREMOTEIO;
+ } else {
+ union i2c_smbus_data data;
+ ret = adap->algo->smbus_xfer(adap, client->addr,
+@@ -195,7 +198,7 @@ static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
+ /* Only select the channel if its different from the last channel */
+ if (data->last_chan != regval) {
+ ret = pca954x_reg_write(muxc->parent, client, regval);
+- data->last_chan = ret ? 0 : regval;
++ data->last_chan = ret < 0 ? 0 : regval;
+ }
+
+ return ret;
+--
+1.9.1
+
diff --git a/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas_4.9.bbappend b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas_4.9.bbappend
index 689f29b..2846618 100644
--- a/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas_4.9.bbappend
+++ b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas_4.9.bbappend
@@ -31,6 +31,7 @@ SRC_URI_append = " \
file://0026-drm-adv7511-add-polling-mode-when-no-irq-available.patch \
file://0027-usb-host-xhci-plat-add-firmware-for-the-R-Car-M3-W-x.patch \
file://0028-usb-host-xhci-rcar-update-firmware-for-R-Car-H3-and-.patch \
+ file://0029-i2c-mux-pca954x-fix-i2c-mux-selection-caching.patch \
file://0030-Gen3-LVDS-cameras.patch \
file://0031-arm64-dts-r8a7795-es1-salvator-x-view-add-ADAS-board.patch \
file://0032-arm64-dts-r8a7795-es1-h3ulcb-view-add-ADAS-board.patch \