I was having intermittent i2c issues on the device until I applied this kernel
patch
which I found online.
Signed-off-by: Richard Purdie <richard.pur...@linuxfoundation.org>
---
.../sl030raspberrypii2ckernel.patch | 32 ++++++++++++++++++++
recipes-kernel/linux/linux-raspberrypi_3.2.27.bb | 1 +
recipes-kernel/linux/linux-raspberrypi_3.6.11.bb | 1 +
3 files changed, 34 insertions(+)
create mode 100644
recipes-kernel/linux/linux-raspberrypi/sl030raspberrypii2ckernel.patch
diff --git
a/recipes-kernel/linux/linux-raspberrypi/sl030raspberrypii2ckernel.patch
b/recipes-kernel/linux/linux-raspberrypi/sl030raspberrypii2ckernel.patch
new file mode 100644
index 0000000..8534ecb
--- /dev/null
+++ b/recipes-kernel/linux/linux-raspberrypi/sl030raspberrypii2ckernel.patch
@@ -0,0 +1,32 @@
+Fix i2c timing errors.
+
+When Transmitting: Make SDA valid quarter of a cycle after the falling edge of
SCL.
+When Receiving: Sample SDA Quarter of a cycle after the rising edge of SCL.
+
+Upstream-Status: Pending
+
+RP 2013/04/21
+
+Index: git/drivers/i2c/busses/i2c-bcm2708.c
+===================================================================
+--- git.orig/drivers/i2c/busses/i2c-bcm2708.c 2013-01-06 17:15:00.754954587
+0000
++++ git/drivers/i2c/busses/i2c-bcm2708.c 2013-01-06 17:50:09.794905741
+0000
+@@ -150,6 +150,7 @@
+ unsigned long bus_hz;
+ u32 cdiv;
+ u32 c = BSC_C_I2CEN | BSC_C_INTD | BSC_C_ST | BSC_C_CLEAR_1;
++ u32 cdel;
+
+ bus_hz = clk_get_rate(bi->clk);
+ cdiv = bus_hz / baudrate;
+@@ -163,6 +164,10 @@
+ bcm2708_wr(bi, BSC_A, bi->msg->addr);
+ bcm2708_wr(bi, BSC_DLEN, bi->msg->len);
+ bcm2708_wr(bi, BSC_C, c);
++
++ cdel = (cdiv / 4) & 0xffff;
++ cdel = cdel << 16 | cdel;
++ bcm2708_wr(bi, BSC_DEL, cdel);
+ }
+
+ static irqreturn_t bcm2708_i2c_interrupt(int irq, void *dev_id)
diff --git a/recipes-kernel/linux/linux-raspberrypi_3.2.27.bb
b/recipes-kernel/linux/linux-raspberrypi_3.2.27.bb
index c7a12e6..a68186b 100644
--- a/recipes-kernel/linux/linux-raspberrypi_3.2.27.bb
+++ b/recipes-kernel/linux/linux-raspberrypi_3.2.27.bb
@@ -8,6 +8,7 @@ PV_append = "+git${SRCREV}"
SRCREV = "10182a3bc434b27740f81c2b836a1af943060241"
SRC_URI =
"git://github.com/raspberrypi/linux.git;protocol=git;branch=rpi-3.2.27 \
+ file://sl030raspberrypii2ckernel.patch \
"
S = "${WORKDIR}/git"
diff --git a/recipes-kernel/linux/linux-raspberrypi_3.6.11.bb
b/recipes-kernel/linux/linux-raspberrypi_3.6.11.bb
index caee7f2..07b0ae8 100644
--- a/recipes-kernel/linux/linux-raspberrypi_3.6.11.bb
+++ b/recipes-kernel/linux/linux-raspberrypi_3.6.11.bb
@@ -8,6 +8,7 @@ PV_append = "+git${SRCREV}"
SRCREV = "31a951046155b27361127d9cf85a1f58719fe9b3"
SRC_URI =
"git://github.com/raspberrypi/linux.git;protocol=git;branch=rpi-3.6.y \
+ file://sl030raspberrypii2ckernel.patch \
"
S = "${WORKDIR}/git"
--
1.7.10.4
_______________________________________________
yocto mailing list
yocto@yoctoproject.org
https://lists.yoctoproject.org/listinfo/yocto
