From 506db2d69eb2d1c8d0b2328b7c1c52e8d033c852 Mon Sep 17 00:00:00 2001 From: Werner Almesberger Date: Mon, 31 Dec 2012 09:51:00 -0300 Subject: [PATCH] libubb/README: describe how to get rid of competing drivers --- libubb/README | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/libubb/README b/libubb/README index 1ef7c83..870bcaa 100644 --- a/libubb/README +++ b/libubb/README @@ -121,3 +121,29 @@ Access to timers, interrupts, etc. include/ubb/regs4740.h gives access to even more registers. Please consult the JZ4740 Programming Manual for details on their use. + + +Competing users of the 8:10 card interface +------------------------------------------ + +Other programs and kernel drivers may compete for access to the +8:10 card interface. The most common conflicts are with the +kernel drivers for MMC (uSD card) and AT86RF230 (atben). + +OpenWRT and JLime start with the MMC driver loaded and active. + +To detach the MMC driver, run + +# echo jz4740-mmc.0 >/sys/bus/platform/drivers/jz4740-mmc/unbind + +To re-attach the MMC driver, run + +# echo jz4740-mmc.0 >/sys/bus/platform/drivers/jz4740-mmc/bind + +To detach the AT86RF230 driver, run + +# cd /sys/bus/spi/drivers/at86rf230 +# echo spi*.0 >unbind + +libubb allows multiple programs to open UBB at the same time, +leaving it up to these programs to coordinate their access.