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2013-05-21Merge branch 'i2c/for-current' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c bugfixes from Wolfram Sang: "These should have been in rc2 but I missed it due to working on devm longer than expected. There is one ID addition, since we are touching the driver anyhow. And the feature bit documentation is one outcome of a debug session and will make it easier for users to work around problems. The rest is typical driver bugfixes." * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: suppress lockdep warning on delete_device i2c: mv64xxx: work around signals causing I2C transactions to be aborted i2c: i801: Document feature bits in modinfo i2c: designware: add Intel BayTrail ACPI ID i2c: designware: always clear interrupts before enabling them i2c: designware: fix RX FIFO overrun
2013-05-18drivers/i2c/busses: don't check resource with devm_ioremap_resourceWolfram Sang
devm_ioremap_resource does sanity checks on the given resource. No need to duplicate this in the driver. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Stephen Warren <swarren@nvidia.com> Acked-by: Barry Song <Baohua.Song@csr.com>
2013-05-17i2c: suppress lockdep warning on delete_deviceAlexander Sverdlin
i2c: suppress lockdep warning on delete_device Since commit 846f99749ab68bbc7f75c74fec305de675b1a1bf the following lockdep warning is thrown in case i2c device is removed (via delete_device sysfs attribute) which contains subdevices (e.g. i2c multiplexer): ============================================= [ INFO: possible recursive locking detected ] 3.8.7-0-sampleversion-fct #8 Tainted: G O --------------------------------------------- bash/3743 is trying to acquire lock: (s_active#110){++++.+}, at: [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8 but task is already holding lock: (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(s_active#110); lock(s_active#110); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by bash/3743: #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff802b3c3c>] sysfs_write_file+0x4c/0x208 #1: (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208 #2: (&adap->userspace_clients_lock/1){+.+.+.}, at: [<ffffffff80454a18>] i2c_sysfs_delete_device+0x90/0x238 #3: (&__lockdep_no_validate__){......}, at: [<ffffffff803dcc24>] device_release_driver+0x24/0x48 stack backtrace: Call Trace: [<ffffffff80575cc8>] dump_stack+0x8/0x34 [<ffffffff801b50fc>] __lock_acquire+0x161c/0x2110 [<ffffffff801b5c3c>] lock_acquire+0x4c/0x70 [<ffffffff802b60cc>] sysfs_addrm_finish+0x19c/0x1e0 [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8 [<ffffffff802b7d8c>] sysfs_remove_group+0x64/0x148 [<ffffffff803d990c>] device_remove_attrs+0x9c/0x1a8 [<ffffffff803d9b1c>] device_del+0x104/0x1d8 [<ffffffff803d9c18>] device_unregister+0x28/0x70 [<ffffffff8045505c>] i2c_del_adapter+0x1cc/0x328 [<ffffffff8045802c>] i2c_del_mux_adapter+0x14/0x38 [<ffffffffc025c108>] pca954x_remove+0x90/0xe0 [pca954x] [<ffffffff804542f8>] i2c_device_remove+0x80/0xe8 [<ffffffff803dca9c>] __device_release_driver+0x74/0xf8 [<ffffffff803dcc2c>] device_release_driver+0x2c/0x48 [<ffffffff803dbc14>] bus_remove_device+0x13c/0x1d8 [<ffffffff803d9b24>] device_del+0x10c/0x1d8 [<ffffffff803d9c18>] device_unregister+0x28/0x70 [<ffffffff80454b08>] i2c_sysfs_delete_device+0x180/0x238 [<ffffffff802b3cd4>] sysfs_write_file+0xe4/0x208 [<ffffffff8023ddc4>] vfs_write+0xbc/0x160 [<ffffffff8023df6c>] SyS_write+0x54/0xd8 [<ffffffff8013d424>] handle_sys64+0x44/0x64 The problem is already known for USB and PCI subsystems. The reason is that delete_device attribute is defined statically in i2c-core.c and used for all devices in i2c subsystem. Discussion of original USB problem: http://lkml.indiana.edu/hypermail/linux/kernel/1204.3/01160.html Commit 356c05d58af05d582e634b54b40050c73609617b introduced new macro to suppress lockdep warnings for this special case and included workaround for USB code. LKML discussion of the workaround: http://lkml.indiana.edu/hypermail/linux/kernel/1205.1/03634.html As i2c case is in principle the same, the same workaround could be used here. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17i2c: mv64xxx: work around signals causing I2C transactions to be abortedRussell King
Do not use interruptible waits in an I2C driver; if a process uses signals (eg, Xorg uses SIGALRM and SIGPIPE) then these signals can cause the I2C driver to abort a transaction in progress by another driver, which can cause that driver to fail. I2C drivers are not expected to abort transactions on signals. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17i2c: i801: Document feature bits in modinfoJean Delvare
Duplicate the feature bits documentation in modinfo, as not every user will read the driver's source code or documentation file. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17i2c: designware: add Intel BayTrail ACPI IDMika Westerberg
This is the same controller as on Intel Lynxpoint but the ACPI ID is different (8086F41). Add support for this. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17i2c: designware: always clear interrupts before enabling themMika Westerberg
If the I2C bus is put to a low power state by an ACPI method it might pull the SDA line low (as its power is removed). Once the bus is put to full power state again, the SDA line is pulled back to high. This transition looks like a STOP condition from the controller point-of-view which sets STOP detected bit in its status register causing the driver to fail subsequent transfers. Fix this by always clearing all interrupts before we start a transfer. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2013-05-17i2c: designware: fix RX FIFO overrunJosef Ahmad
i2c_dw_xfer_msg() pushes a number of bytes to transmit/receive to/from the bus into the TX FIFO. For master-rx transactions, the maximum amount of data that can be received is calculated depending solely on TX and RX FIFO load. This is racy - TX FIFO may contain master-rx data yet to be processed, which will eventually land into the RX FIFO. This data is not taken into account and the function may request more data than the controller is actually capable of storing. This patch ensures the driver takes into account the outstanding master-rx data in TX FIFO to prevent RX FIFO overrun. Signed-off-by: Josef Ahmad <josef.ahmad@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2013-05-09Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linuxLinus Torvalds
Pull removal of GENERIC_GPIO from Grant Likely: "GENERIC_GPIO now synonymous with GPIOLIB. There are no longer any valid cases for enableing GENERIC_GPIO without GPIOLIB, even though it is possible to do so which has been causing confusion and breakage. This branch does the work to completely eliminate GENERIC_GPIO." * tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: gpio: update gpio Chinese documentation Remove GENERIC_GPIO config option Convert selectors of GENERIC_GPIO to GPIOLIB blackfin: force use of gpiolib m68k: coldfire: use gpiolib mips: pnx833x: remove requirement for GENERIC_GPIO openrisc: default GENERIC_GPIO to false avr32: default GENERIC_GPIO to false xtensa: remove explicit selection of GENERIC_GPIO sh: replace CONFIG_GENERIC_GPIO by CONFIG_GPIOLIB powerpc: remove redundant GENERIC_GPIO selection unicore32: default GENERIC_GPIO to false unicore32: remove unneeded select GENERIC_GPIO arm: plat-orion: use GPIO driver on CONFIG_GPIOLIB arm: remove redundant GENERIC_GPIO selection mips: alchemy: require gpiolib mips: txx9: change GENERIC_GPIO to GPIOLIB mips: loongson: use GPIO driver on CONFIG_GPIOLIB mips: remove redundant GENERIC_GPIO select
2013-05-07Merge tag 'dt-for-linus-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC device tree updates (part 2) from Arnd Bergmann: "These are mostly new device tree bindings for existing drivers, as well as changes to the device tree source files to add support for those devices, and a couple of new boards, most notably Samsung's Exynos5 based Chromebook. The changes depend on earlier platform specific updates and touch the usual platforms: omap, exynos, tegra, mxs, mvebu and davinci." * tag 'dt-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (169 commits) ARM: exynos: dts: cros5250: add EC device ARM: dts: Add sbs-battery for exynos5250-snow ARM: dts: Add i2c-arbitrator bus for exynos5250-snow ARM: dts: add mshc controller node for Exynos4x12 SoCs ARM: dts: Add chip-id controller node on Exynos4/5 SoC ARM: EXYNOS: Create virtual I/O mapping for Chip-ID controller using device tree ARM: davinci: da850-evm: add SPI flash support ARM: davinci: da850: override SPI DT node device name ARM: davinci: da850: add SPI1 DT node spi/davinci: add DT binding documentation spi/davinci: no wildcards in DT compatible property ARM: dts: mvebu: Convert mvebu device tree files to 64 bits ARM: dts: mvebu: introduce internal-regs node ARM: dts: mvebu: Convert all the mvebu files to use the range property ARM: dts: mvebu: move all peripherals inside soc ARM: dts: mvebu: fix cpus section indentation ARM: davinci: da850: add EHRPWM & ECAP DT node ARM/dts: OMAP3: fix pinctrl-single configuration ARM: dts: Add OMAP3430 SDP NOR flash memory binding ARM: dts: Add NOR flash bindings for OMAP2420 H4 ...
2013-05-06Merge branch 'late/dt' into next/dt2Arnd Bergmann
This is support for the ARM Chromebook, originally scheduled as a "late" pull request. Since it's already late now, we can combine this into the existing next/dt2 branch. * late/dt: ARM: exynos: dts: cros5250: add EC device ARM: dts: Add sbs-battery for exynos5250-snow ARM: dts: Add i2c-arbitrator bus for exynos5250-snow ARM: dts: Add chip-id controller node on Exynos4/5 SoC ARM: EXYNOS: Create virtual I/O mapping for Chip-ID controller using device tree
2013-05-02Merge branch 'i2c/for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c changes from Wolfram Sang: - an arbitration driver. While the driver is quite simple, it caused discussion if we need additional arbitration on top of the one specified in the I2C standard. Conclusion is that I accept a few generic mechanisms, but not very specific ones. - the core lost the detach_adapter() call. It has no users anymore and was in the way for other cleanups. attach_adapter() is sadly still there since there are users waiting to be converted. - the core gained a bus recovery infrastructure. I2C defines a way to recover if the data line is stalled. This mechanism is now in the core and drivers can now pass some data to make use of it. - bigger driver cleanups for designware, s3c2410 - removing superfluous refcounting from drivers - removing Ben Dooks as second maintainer due to inactivity. Thanks for all your work so far, Ben! - bugfixes, feature additions, devicetree fixups, simplifications... * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits) i2c: xiic: must always write 16-bit words to TX_FIFO i2c: octeon: use HZ in timeout value i2c: octeon: Fix i2c fail problem when a process is terminated by a signal i2c: designware-pci: drop superfluous {get|put}_device i2c: designware-plat: drop superfluous {get|put}_device i2c: davinci: drop superfluous {get|put}_device MAINTAINERS: Ben Dooks is inactive regarding I2C i2c: mux: Add i2c-arb-gpio-challenge 'mux' driver i2c: at91: convert to dma_request_slave_channel_compat() i2c: mxs: do error checking and handling in PIO mode i2c: mxs: remove races in PIO code i2c-designware: switch to use runtime PM autosuspend i2c-designware: use usleep_range() in the busy-loop i2c-designware: enable/disable the controller properly i2c-designware: use dynamic adapter numbering on Lynxpoint i2c-designware-pci: use managed functions pcim_* and devm_* i2c-designware-pci: use dev_err() instead of printk() i2c-designware: move to managed functions (devm_*) i2c: remove CONFIG_HOTPLUG ifdefs i2c: s3c2410: Add SMBus emulation for block read ...
2013-04-30Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "Usual stuff, mostly comment fixes, typo fixes, printk fixes and small code cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (45 commits) mm: Convert print_symbol to %pSR gfs2: Convert print_symbol to %pSR m32r: Convert print_symbol to %pSR iostats.txt: add easy-to-find description for field 6 x86 cmpxchg.h: fix wrong comment treewide: Fix typo in printk and comments doc: devicetree: Fix various typos docbook: fix 8250 naming in device-drivers pata_pdc2027x: Fix compiler warning treewide: Fix typo in printks mei: Fix comments in drivers/misc/mei treewide: Fix typos in kernel messages pm44xx: Fix comment for "CONFIG_CPU_IDLE" doc: Fix typo "CONFIG_CGROUP_CGROUP_MEMCG_SWAP" mmzone: correct "pags" to "pages" in comment. kernel-parameters: remove outdated 'noresidual' parameter Remove spurious _H suffixes from ifdef comments sound: Remove stray pluses from Kconfig file radio-shark: Fix printk "CONFIG_LED_CLASS" doc: put proper reference to CONFIG_MODULE_SIG_ENFORCE ...
2013-04-23i2c: xiic: must always write 16-bit words to TX_FIFOSteven A. Falco
The TX_FIFO register is 10 bits wide. The lower 8 bits are the data to be written, while the upper two bits are flags to indicate stop/start. The driver apparently attempted to optimize write access, by only writing a byte in those cases where the stop/start bits are zero. However, we have seen cases where the lower byte is duplicated onto the upper byte by the hardware, which causes inadvertent stop/starts. This patch changes the write access to the transmit FIFO to always be 16 bits wide. Signed off by: Steven A. Falco <sfalco@harris.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2013-04-23i2c: octeon: use HZ in timeout value송은봉
HZ based value is better than a magic number. Signed-off-by: Eunbong Song <eunb.song@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-19i2c: octeon: Fix i2c fail problem when a process is terminated by a signal송은봉
I've been debugging the abnormal operation of i2c on octeon. If a process is terminated by signal in the middle of i2c operation, next i2c read operation which is done by another process was failed. So i changed to ignore signal in the middle of i2c operation. After that the problem was not reproduced. Signed-off-by: Eunbong Song <eunb.song@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-19i2c: designware-pci: drop superfluous {get|put}_deviceWolfram Sang
Driver core already takes care of refcounting, no need to do this on driver level again. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-04-19i2c: designware-plat: drop superfluous {get|put}_deviceWolfram Sang
Driver core already takes care of refcounting, no need to do this on driver level again. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-04-19i2c: davinci: drop superfluous {get|put}_deviceWolfram Sang
Driver core already takes care of refcounting, no need to do this on driver level again. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Sekhar Nori <nsekhar@ti.com>
2013-04-17i2c: mux: Add i2c-arb-gpio-challenge 'mux' driverDoug Anderson
The i2c-arb-gpio-challenge driver implements an I2C arbitration scheme where masters need to claim the bus with a GPIO before they can start a transaction. This should generally only be used when standard I2C multimaster isn't appropriate for some reason (errata/bugs). This driver is based on code that Simon Glass added to the i2c-s3c2410 driver in the Chrome OS kernel 3.4 tree. The current incarnation as a mux driver is as suggested by Grant Likely. See <https://patchwork.kernel.org/patch/1877311/> for some history. Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com> Reviewed-by: Stephen Warren <swarren@nvidia.com> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-16Convert selectors of GENERIC_GPIO to GPIOLIBAlexandre Courbot
GENERIC_GPIO is now equivalent to GPIOLIB and features that depended on GENERIC_GPIO can now depend on GPIOLIB to allow removal of this option. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Grant Likely <grant.likely@secretlab.ca>
2013-04-16i2c: at91: convert to dma_request_slave_channel_compat()Ludovic Desroches
Use generic DMA DT helper. Platforms booting with or without DT populated are both supported. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c: mxs: do error checking and handling in PIO modeLucas Stach
In PIO mode we can end up with the same errors as in DMA mode, but as IRQs are disabled there we have to check for them manually after each command. Also don't use the big controller reset hammer when receiving a NAK from a slave. It's sufficient to tell the controller to continue at a clean state. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Tested-by: Marek Vasut <marex@denx.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c: mxs: remove races in PIO codeLucas Stach
This commit fixes the three following races in PIO code: - The CTRL0 register is racy in itself, when programming transfer state and run bit in the same cycle the hardware sometimes ends up using the state from the last transfer. Fix this by programming state in one cycle, make sure the write is flushed down APBX bus by reading back the reg and only then trigger the run bit. - Only clear the DMAREQ bit in DEBUG0 after the read/write to the data reg happened. Otherwise we are racing with the hardware about who touches the data reg first. - When checking for completion of a transfer it's not sufficient to check if the data engine finished, but also a check for i2c bus idle is needed. In PIO mode we are really fast to program the next transfer after a finished one, so the controller possibly tries to start a new transfer while the clkgen engine is still busy writing the NAK/STOP from the last transfer to the bus. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware: switch to use runtime PM autosuspendMika Westerberg
Using autosuspend helps to reduce the resume latency in situations where another I2C message is going to be started soon. For example with HID over I2C touch panels we get several messages in a short period of time while the touch panel is in use. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware: use usleep_range() in the busy-loopMika Westerberg
This is not an atomic context so there is no need to use mdelay() but instead use usleep_range(). Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware: enable/disable the controller properlyMika Westerberg
The correct way to disable or enable the controller is to wait until the DW_IC_ENABLE_STATUS register bit matches the bit we program into DW_IC_ENABLE register. This procedure is described in the DesignWare I2C databook. By doing this we can be sure that the controller is in correct state once the function returns. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware: use dynamic adapter numbering on LynxpointMika Westerberg
It is not good idea to mix static and dynamic I2C adapter numbering. In this particular case on Lynxpoint we had graphics I2C adapter which took the first numbers preventing the designware I2C driver from using the adapter numbers it preferred. Since Lynxpoint support was just introduced and there is no hardware available outside Intel we can fix this by switching to use dynamic adapter numbering instead of static. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware-pci: use managed functions pcim_* and devm_*Andy Shevchenko
This makes the error handling much more simpler than open-coding everything and in addition makes the probe function smaller an tidier. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware-pci: use dev_err() instead of printk()Andy Shevchenko
With dev_err() we can get the device instance printed as well and is pretty much standard to use dev_* macros in the drivers anyway. In addition correct the indentation of probe() arguments. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-15i2c-designware: move to managed functions (devm_*)Andy Shevchenko
This makes the error handling much more simpler than open-coding everything and in addition makes the probe function smaller and tidier. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-09i2c: remove CONFIG_HOTPLUG ifdefsYijing Wang
CONFIG_HOTPLUG is going away as an option, cleanup CONFIG_HOTPLUG ifdefs in i2c files. Signed-off-by: Yijing Wang <wangyijing@huawei.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-09i2c: s3c2410: Add SMBus emulation for block readJaemin Yoo
SMBus read and write are supported by the emulation layer of i2c framework if the controller doesn't have SMBus features. I2C_M_RECV_LEN flag is used to let i2c drivers know rx length is not yet determined but will be read to the first byte in rx buffer. s3c2410 doesn't handle this flag. So only one byte is read from slave. There fore following two features are added to the driver code. 1. skip rx length check if I2C_M_RECV_LEN is set and the length is 1. 2. add actual bytes to the rx length after reading first bytes if I2C_M_RECV_LEN. I2C_M_RECV_LEN is only set for SMBus command. So this code does not affect legacy codes which only use i2c command for s3c2410. Signed-off-by: Jaemin Yoo <jmin.yoo@samsung.com> Tested-by: Prasanna Kumar <prasanna.ps@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-04i2c: i2c-mxs: move to use generic DMA helperShawn Guo
With the generic DMA device tree helper supported by mxs-dma driver, client devices only need to call dma_request_slave_channel() for requesting a DMA channel from dmaengine. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02ACPI / I2C: Use parent's ACPI_HANDLE() in acpi_i2c_register_devices()Rafael J. Wysocki
The ACPI handle of struct i2c_adapter's dev member should not be set, because this causes that struct i2c_adapter to be associated with the ACPI device node corresponding to its parent as the second "physical_device", which is incorrect (this happens during the registration of struct i2c_adapter). Consequently, acpi_i2c_register_devices() should use the ACPI handle of the parent of the struct i2c_adapter it is called for rather than the struct i2c_adapter's ACPI handle (which should be NULL). Make that happen and modify the i2c-designware-platdrv driver, which currently is the only driver for ACPI-enumerated I2C controller chips, not to set the ACPI handle for the struct i2c_adapter it creates. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Aaron Lu <aaron.lu@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: Make the return type of i2c_del_mux_adapter() voidLars-Peter Clausen
i2c_del_mux_adapter always returns 0 and none of it current users check its return value anyway. It is also an essential requirement of the Linux device driver model, that functions which may be called from a device's remove callback to free resources provided by the device, are not allowed to fail. This is the case for i2c_del_mux_adapter(), so make its return type void to make the fact that it won't fail explicit. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: Ignore the return value of i2c_del_mux_adapter()Lars-Peter Clausen
i2c_del_mux_adapter() always returns 0. So all checks testing whether it will be non zero will always evaluate to false and the conditional code is dead code. This patch updates all callers of i2c_del_mux_adapter() to ignore its return value and assume that it will always succeed (which it will). A subsequent patch will make the return type of i2c_del_mux_adapter() void. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: Make return type of i2c_del_adapter() voidLars-Peter Clausen
i2c_del_adapter() is usually called from a drivers remove callback. The Linux device driver model does not allow the remove callback to fail and all resources allocated in the probe callback need to be freed, as well as all resources which have been provided to the rest of the kernel(for example a I2C adapter) need to be revoked. So any function revoking such resources isn't allowed to fail either. i2c_del_adapter() adheres to this requirement and will never fail. But i2c_del_adapter()'s return type is int, which may cause driver authors to think that it can fail. This led to code constructs like: ret = i2c_del_adapter(...); BUG_ON(ret); Since i2c_del_adapter() always returns 0 the BUG_ON is never hit and essentially becomes dead code, which means it can be removed. Making the return type of i2c_del_adapter() void makes it explicit that the function will never fail and should prevent constructs like the above from re-appearing in the kernel code. All callers of i2c_del_adapter() have already been updated in a previous patch to ignore the return value, so the conversion of the return type from int to void can be done without causing any build failures. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: Ignore return value of i2c_del_adapter()Lars-Peter Clausen
i2c_del_adapter() always returns 0. So all checks testing whether it will be non zero will always evaluate to false and the conditional code is dead code. This patch updates all callers of i2c_del_mux_adapter() to ignore the return value and assume that it will always succeed (which it will). In a subsequent patch the return type of i2c_del_adapter() will be made void. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Ben Hutchings <bhutchings@solarflare.com> Reviewed-by: Jean Delvare <khali@linux-fr.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: i2c_del_adapter: Don't treat removing a non-registered adapter as errorLars-Peter Clausen
Currently i2c_del_adapter() returns -EINVAL when it gets an adapter which is not registered. But none of the users of i2c_del_adapter() depend on this behavior, so for the sake of being able to sanitize the return type of i2c_del_adapter argue, that the purpose of i2c_del_adapter() is to remove an I2C adapter from the system. If the adapter is not registered in the first place this becomes a no-op. So we can return success without having to do anything. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: Remove detach_adapterLars-Peter Clausen
The detach_adapter callback has been deprecated for quite some time and has no user left. Keeping it alive blocks other cleanups, so remove it. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-29i2c: at91: Use of_match_ptr() macroSachin Kamat
This eliminates having an #ifdef returning NULL for the case when OF is disabled. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-29i2c: davinci: update to devm_* APIVishwanathrao Badarkhe, Manish
Update the code to use devm_* API so that driver core will manage resources. Signed-off-by: Vishwanathrao Badarkhe, Manish <manishv.b@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-29i2c: davinci: rename recover bus functionsWolfram Sang
Since we have generic i2c bus recover routines now, these custom ones need to be renamed to fix the namespace clash. Proper conversion needs to be done by someone who has access to the hardware. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-27i2c: mux: gpio: Check gpio_direction_output return valueJean Delvare
gpio_direction_output() may fail, check for that and deal with it appropriately. Also log an error message if gpio_request() fails. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-27i2c: gpio: Add support for deferred probingJean Delvare
GPIOs may not be available immediately when i2c-gpio looks for them. Implement support for deferred probing so that probing can be attempted again later when GPIO pins are finally available. Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Bo Shen <voice.shen@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-24i2c: s3c2410: fixup the styling of the newly moved register definitionsHeiko Stübner
Make them conform more to established standards. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-24i2c: s3c2410: move mach/regs-iic.h into i2c-s3c2410 device driverHeiko Stübner
The register definitions are only used in the driver itself. This also removes the last dependency on plat/ includes from the i2c driver. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-24i2c: ismt: remove duplicate constWolfram Sang
(SMATCH) drivers/i2c/busses/i2c-ismt.c:186:14: warning: duplicate const Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-24i2c: tegra: assume CONFIG_OF, remove platform dataStephen Warren
Tegra only supports, and always enables, device tree. Remove all ifdefs and runtime checks for DT support from the driver. Platform data is therefore no longer required. Delete the header that defines it. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>