linux/drivers/i2c, branch v3.19

i2c: sh_mobile: terminate DMA reads properly

2015-01-30T16:58:43Z

DMA read requests could miss proper termination, so two more bytes would have been read via PIO overwriting the end of the buffer with wrong data. Make DMA stop handling more readable while we are here. Signed-off-by: Wolfram Sang Signed-off-by: Wolfram Sang

i2c: Only include slave support if selected

2015-01-26T21:05:20Z

Make the slave support depend on CONFIG_I2C_SLAVE. Otherwise it gets included unconditionally, even when it is not needed. I2C bus drivers which implement slave support must select I2C_SLAVE. Signed-off-by: Jean Delvare Signed-off-by: Wolfram Sang

i2c: s3c2410: fix ABBA deadlock by keeping clock prepared

2015-01-24T04:43:45Z

This patch solves deadlock between clock prepare mutex and regmap mutex reported by Tomasz Figa in [1] by implementing solution from [2]: "always leave the clock of the i2c controller in a prepared state". [1] https://lkml.org/lkml/2014/7/2/171 [2] https://lkml.org/lkml/2014/7/2/207 On each i2c transfer handled by s3c24xx_i2c_xfer(), clk_prepare_enable() was called, which calls clk_prepare() then clk_enable(). clk_prepare() takes prepare_lock mutex before proceeding. Note that i2c transfer functions are invoked from many places in kernel, typically with some other additional lock held. It may happen that function on CPU1 (e.g. regmap_update_bits()) has taken a mutex (i.e. regmap lock mutex) then it attempts i2c communication in order to proceed (so it needs to obtain clock related prepare_lock mutex during transfer preparation stage due to clk_prepare() call). At the same time other task on CPU0 wants to operate on clock (e.g. to (un)prepare clock for some other reason) so it has taken prepare_lock mutex. CPU0: CPU1: clk_disable_unused() regulator_disable() clk_prepare_lock() map->lock(map->lock_arg) regmap_read() s3c24xx_i2c_xfer() map->lock(map->lock_arg) clk_prepare_lock() Implemented solution from [2] leaves i2c clock prepared. Preparation is done in s3c24xx_i2c_probe() function. Without this patch, it is immediately unprepared by clk_disable_unprepare() call. I've replaced this call with clk_disable() and I've added clk_unprepare() call in s3c24xx_i2c_remove(). The s3c24xx_i2c_xfer() function now uses clk_enable() instead of clk_prepare_enable() (and clk_disable() instead of clk_unprepare_disable()). Signed-off-by: Paul Osmialowski Reviewed-by: Krzysztof Kozlowski Signed-off-by: Wolfram Sang Cc: stable@kernel.org

i2c: slave-eeprom: fix boundary check when using sysfs

2015-01-24T04:43:44Z

Due to a copy&paste error, the last byte of the shared memory was not accessible via sysfs. Reported-by: Debora Grosse Signed-off-by: Wolfram Sang Acked-by: Laurent Pinchart Signed-off-by: Wolfram Sang

Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

2014-12-20T21:52:52Z

Pull more i2c updates from Wolfram Sang: "Included are two bugfixes needing some bigger refactoring (sh_mobile: deferred probe with DMA, mv64xxx: fix offload support) and one deprecated driver removal I thought would go in via ppc but I misunderstood. It has a proper ack from BenH" * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: sh_mobile: fix uninitialized var when debug is enabled macintosh: therm_pm72: delete deprecated driver i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA i2c: sh_mobile: rework deferred probing i2c: sh_mobile: refactor DMA setup i2c: mv64xxx: rework offload support to fix several problems i2c: mv64xxx: use BIT() macro for register value definitions

i2c: sh_mobile: fix uninitialized var when debug is enabled

2014-12-20T08:28:09Z

Signed-off-by: Wolfram Sang Signed-off-by: Wolfram Sang

Merge tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

2014-12-19T20:57:45Z

Pull second batch of powerpc updates from Michael Ellerman: "The highlight is the series that reworks the idle management on powernv, which allows us to use deeper idle states on those machines. There's the fix from Anton for the "BUG at kernel/smpboot.c:134!" problem. An i2c driver for powernv. This is acked by Wolfram Sang, and he asked that we take it through the powerpc tree. A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of the audit maintainers. A patch from Ben to export the symbol map of our OPAL firmware as a sysfs file, so that tools can use it. Also some CXL fixes, a couple of powerpc perf fixes, a fix for smt-enabled, and the patch to add __force to get_user() so we can use bitwise types" * tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/powernv: Ignore smt-enabled on Power8 and later powerpc/uaccess: Allow get_user() with bitwise types powerpc/powernv: Expose OPAL firmware symbol map powernv/powerpc: Add winkle support for offline cpus powernv/cpuidle: Redesign idle states management powerpc/powernv: Enable Offline CPUs to enter deep idle states powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode i2c: Driver to expose PowerNV platform i2c busses powerpc: add little endian flag to syscall_get_arch() power/perf/hv-24x7: Use kmem_cache_free() instead of kfree powerpc/perf/hv-24x7: Use per-cpu page buffer cxl: Unmap MMIO regions when detaching a context cxl: Add timeout to process element commands cxl: Change contexts_lock to a mutex to fix sleep while atomic bug powerpc: Secondary CPUs must set cpu_callin_map after setting active and online

i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA

2014-12-17T18:26:09Z

If NO_DMA=y: drivers/built-in.o: In function `sh_mobile_i2c_dma_unmap': i2c-sh_mobile.c:(.text+0x60de42): undefined reference to `dma_unmap_single' drivers/built-in.o: In function `sh_mobile_i2c_xfer_dma': i2c-sh_mobile.c:(.text+0x60df22): undefined reference to `dma_map_single' i2c-sh_mobile.c:(.text+0x60df2e): undefined reference to `dma_mapping_error' Signed-off-by: Geert Uytterhoeven Signed-off-by: Wolfram Sang

i2c: sh_mobile: rework deferred probing

2014-12-17T18:26:08Z

DMA is opt-in for this driver. So, we can't use deferred probing for requesting DMA channels in probe, because our driver would get endlessly deferred if DMA support is compiled in AND the DMA driver is missing. Because we can't know when the DMA driver might show up, we always try again when a DMA transfer would be possible. The downside is that there is more overhead for setting up PIO transfers under the above scenario. But well, having DMA enabled and the proper DMA driver missing looks like a broken or test config anyhow. Reported-by: Geert Uytterhoeven Signed-off-by: Wolfram Sang Signed-off-by: Wolfram Sang

i2c: sh_mobile: refactor DMA setup

2014-12-17T18:26:07Z

Refactor DMA setup to keep the errno so we can implement better deferred probe support in the next step. Signed-off-by: Wolfram Sang Signed-off-by: Wolfram Sang