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* i2c: fix leaked device refcount on of_find_i2c_* error pathVladimir Zapolskiy2015-08-011-6/+14
| | | | | | | | | If of_find_i2c_device_by_node() or of_find_i2c_adapter_by_node() find a device by node, but its type does not match, a reference to that device is still held. This change fixes the problem. Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: Fix typo in i2c-bfin-twi.cMasanari Iida2015-07-311-2/+2
| | | | | | | | | This patch fix some typos found in a printk message and MODULE_DESCRIPTION. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: omap: fix bus recovery setupJan Luebbe2015-07-311-0/+11
| | | | | | | | | | | | | | | | | At least on the AM335x, enabling OMAP_I2C_SYSTEST_ST_EN is not enough to allow direct access to the SCL and SDA pins. In addition to ST_EN, we need to set the TMODE to 0b11 (Loop back & SDA/SCL IO mode select). Also, as the reset values of SCL_O and SDA_O are 0 (which means "drive low level"), we need to set them to 1 (which means "high-impedance") to avoid unwanted changes on the pins. As a precaution, reset all these bits to their default values after recovery is complete. Signed-off-by: Jan Luebbe <jlu@pengutronix.de> Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: core: only use set_scl for bus recovery after calling prepare_recoveryJan Luebbe2015-07-311-1/+3
| | | | | | | | | | | | Using set_scl may be ineffective before calling the driver specific prepare_recovery callback, which might change into a test mode. So instead of setting SCL in i2c_generic_scl_recovery, move it to i2c_generic_recovery (after the optional prepare_recovery). Signed-off-by: Jan Luebbe <jlu@pengutronix.de> Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: slave eeprom: clean up sysfs bin attribute read()/write()Vladimir Zapolskiy2015-07-311-6/+0
| | | | | | | | | | | The change removes redundant sysfs binary file boundary checks, since this task is already done on caller side in fs/sysfs/file.c Note, on file size overflow read() now returns 0, and this is a correct and expected EOF notification according to POSIX. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: Mark instantiated device nodes with OF_POPULATEPantelis Antoniou2015-07-091-1/+15
| | | | | | | | | | | | Mark (and unmark) device nodes with the POPULATE flag as appropriate. This is required to avoid multi probing when using I2C and device overlays containing a mux. This patch is also more careful with the release of the adapter device which caused a deadlock with muxes, and does not break the build on !OF since the node flag accessors are not defined then. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: jz4780: Fix return value if probe failsAxel Lin2015-07-091-7/+8
| | | | | | | | | Current code returns 0 if fails to read clock-frequency DT property, fix it. Also add checking return value of clk_prepare_enable and propagate return value of devm_request_irq. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: xgene-slimpro: Fix missing mbox_free_channel call in probe error pathAxel Lin2015-07-091-0/+1
| | | | | | | Free requested mailbox channel before return error. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: I2C_MT65XX should depend on HAS_DMAGeert Uytterhoeven2015-07-091-0/+1
| | | | | | | | | | | | | If NO_DMA=y: ERROR: "dma_unmap_single" [drivers/i2c/busses/i2c-mt65xx.ko] undefined! ERROR: "dma_mapping_error" [drivers/i2c/busses/i2c-mt65xx.ko] undefined! ERROR: "dma_map_single" [drivers/i2c/busses/i2c-mt65xx.ko] undefined! Add a dependency on HAS_DMA to fix this. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* Merge tag 'char-misc-4.2-rc1' of ↵Linus Torvalds2015-06-261-5/+33
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here's the big char/misc driver pull request for 4.2-rc1. Lots of mei, extcon, coresight, uio, mic, and other driver updates in here. Full details in the shortlog. All of these have been in linux-next for some time with no reported problems" * tag 'char-misc-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (176 commits) mei: me: wait for power gating exit confirmation mei: reset flow control on the last client disconnection MAINTAINERS: mei: add mei_cl_bus.h to maintained file list misc: sram: sort and clean up included headers misc: sram: move reserved block logic out of probe function misc: sram: add private struct device and virt_base members misc: sram: report correct SRAM pool size misc: sram: bump error message level on unclean driver unbinding misc: sram: fix device node reference leak on error misc: sram: fix enabled clock leak on error path misc: mic: Fix reported static checker warning misc: mic: Fix randconfig build error by including errno.h uio: pruss: Drop depends on ARCH_DAVINCI_DA850 from config uio: pruss: Add CONFIG_HAS_IOMEM dependence uio: pruss: Include <linux/sizes.h> extcon: Redefine the unique id of supported external connectors without 'enum extcon' type char:xilinx_hwicap:buffer_icap - change 1/0 to true/false for bool type variable in function buffer_icap_set_configuration(). Drivers: hv: vmbus: Allocate ring buffer memory in NUMA aware fashion parport: check exclusive access before register w1: use correct lock on error in w1_seq_show() ...
| * i2c-parport: use new parport device modelSudip Mukherjee2015-06-011-5/+10
| | | | | | | | | | | | | | | | | | Modify i2c-parport driver to use the new parallel port device model. Tested-by: Jean Delvare <jdelvare@suse.de> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i2c-parport: define ports to connectSudip Mukherjee2015-06-011-0/+23
| | | | | | | | | | | | | | | | | | | | | | As of now i2c-parport was connecting to all the available parallel ports. Lets limit that to maximum of 4 instances and at the same time define which instance connects to which parallel port. Tested-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge branch 'i2c/for-4.2' of ↵Linus Torvalds2015-06-2528-154/+2602
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "Highlights: - new drivers for Mediatek I2C, APM X-Gene, Broadcom Settop - major updates to at91, davinci - bugfixes to the mux infrastructure when dealing with the new quirk mechanism - more users for the bus recovery feature - further improvements to the slave framework Plus the usual bunch of smaller driver and core improvements and fixes. There is one patch removing old code from an ARM platform. This has been acked by the sh_mobile maintainer Simon Horman" * 'i2c/for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (48 commits) i2c: busses: i2c-bcm2835: limits cdiv to allowed values i2c: sh_mobile: use proper type for timeout i2c: sh_mobile: use adapter default for timeout i2c: rcar: use proper type for timeout i2c: rcar: use adapter default for timeout i2c: designware: Make sure the device is suspended before disabling runtime PM i2c: tegra: apply size limit quirk i2c: tegra: don't advertise SMBUS_QUICK i2c: octeon: remove unused signal handling i2c: davinci: Optimize SCL generation i2c: mux: pca954x: Use __i2c_transfer because of quirks i2c: mux: Use __i2c_transfer() instead of calling parent's master_xfer() i2c: use parent adapter quirks in mux i2c: bcm2835: clear reserved bits in S-Register ARM: shmobile: r8a7740: remove I2C errata handling i2c: sh_mobile: add errata workaround i2c: at91: fix code checker warnings i2c: busses: xgene-slimpro: fix incorrect __init declation for probe i2c: davinci: Avoid sending to own address i2c: davinci: Refactor i2c_davinci_wait_bus_not_busy() ...
| * | i2c: busses: i2c-bcm2835: limits cdiv to allowed valuesSilvan Wicki2015-06-231-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Checks if the cdiv value is in between min (0x2) and max (0xFFFE) supported values by the bcm2835. If not, it returns -ENODEV. See page 33/34 of BCM2835-ARM-Peripherals.pdf for the DIV register. https://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf Signed-off-by: Silvan Wicki <linux_wi@tinag.ch> [wsa: resolved a merge conflict] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: sh_mobile: use proper type for timeoutWolfram Sang2015-06-231-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | wait_event_timeout returns long, not int. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: sh_mobile: use adapter default for timeoutWolfram Sang2015-06-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 5 seconds is a very large timeout, and it is hardcoded. Use the default timeout from 'struct adapter' which is 1 second. It can also be modified from userspace for specific workloads via i2c-dev. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: rcar: use proper type for timeoutWolfram Sang2015-06-231-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | wait_event_timeout returns long, not int. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: rcar: use adapter default for timeoutWolfram Sang2015-06-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 5 seconds is a very large timeout, and it is hardcoded. Use the default timeout from 'struct adapter' which is 1 second. It can also be modified from userspace for specific workloads via i2c-dev. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: designware: Make sure the device is suspended before disabling runtime PMMika Westerberg2015-06-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The driver calls pm_runtime_put() right before pm_runtime_disable() in its ->remove() hook to make sure clock is gated etc. However, it turns out that pm_runtime_put() only calls ->idle() hook without actually suspending anything. The following pm_runtime_disable() will prevent the driver from suspending thus leaving it "active". It is better to suspend the device synchronously to make sure it is actually suspended before disabling runtime PM from it. While there, undo call to pm_runtime_use_autosuspend(). Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: apply size limit quirkWolfram Sang2015-06-211-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | payload_size is a 12 bit field in the HW register, so add a limit for this size. That way we gracefully reject the message beforehand instead of generating an OOPS while transferring. Verified using some older Tegra2 documentation and a more recent Jetson TK1 board. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
| * | i2c: tegra: don't advertise SMBUS_QUICKWolfram Sang2015-06-211-2/+2
| | | | | | | | | | | | | | | | | | | | | This HW cannot send 0-byte-length messages and the driver discards them. So, we should not advertise SMBUS_QUICK. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: octeon: remove unused signal handlingNicholas Mc Guire2015-06-171-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'commit 2637e5fd232d ("i2c: octeon: Fix i2c fail problem when a process is terminated by a signal")' removed the wait_event_interruptible_timeout to prevent half/mixed i2c messages from being sent/recievd but forgot to drop the signal handling case in the return handling. This just removes this dead code. While at it the return variable is adjusted to the type expected. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: davinci: Optimize SCL generationAlexander Sverdlin2015-06-171-3/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are several cases where current clock configuration algorithm produces not optimal results: - truncation in "clk" calculation leads to the fact that actual BUS frequency will be always higher than spec except two exact module frequences 8MHz and 12MHz in the whole 7-12MHz range of permitted frequences - driver configures SCL HIGH to LOW ratio always 1 to 1 and this doesn't work well in 400kHz case, namely minimum time of LOW state (according to I2C Spec 2.1) 1.3us will not be fulfilled. HIGH to LOW ratio 1 to 2 would be more approriate here. Signed-off-by: Michael Lawnick <michael.lawnick@nokia.com> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: mux: pca954x: Use __i2c_transfer because of quirksAlexander Sverdlin2015-06-172-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pca9541 and pca954x are calling master_xfer() of the parent adapter directly thus bypassing the quirks checks of the adapter. Use __i2c_transfer() instead. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Tested-by: Łukasz Gemborowski <lukasz.gemborowski@nokia.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Fixes: b7f625840267b1 ("i2c: add quirk checks to core")
| * | i2c: mux: Use __i2c_transfer() instead of calling parent's master_xfer()Alexander Sverdlin2015-06-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Newly introduced quirks infrastructure doesn't work for the devices behind MUXes because MUX's master_xfer() calls parent's master_xfer() directly without checking the quirks. Instead of duplicating check code in MUX just call __i2c_transfer() instead. This has a side effect on tracing (messages will appear on both MUX bus and parent bus), but maybe that's not bad at the end. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Tested-by: Łukasz Gemborowski <lukasz.gemborowski@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Fixes: b7f625840267b1 ("i2c: add quirk checks to core")
| * | i2c: use parent adapter quirks in muxAlexander Sverdlin2015-06-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Inherit parent adapter quirks in MUX in case the devices on the multiplexed buses are interested in the adapter limitations. Signed-off-by: Łukasz Gemborowski <lukasz.gemborowski@nokia.com> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Fixes: b7f625840267b1 ("i2c: add quirk checks to core")
| * | i2c: bcm2835: clear reserved bits in S-RegisterSilvan Wicki2015-06-171-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The datasheet mentions on page 31 that the bits 10-31 must be read as don't care and written as 0. https://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf We cannot guarantee that we read bits 10-31 as always 0 (because the datasheet says read as don't care). We clear the bits with a bitmask to prevent writing back unknown data at the reserved bits. Signed-off-by: Silvan Wicki <linux_wi@tinag.ch> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: sh_mobile: add errata workaroundWolfram Sang2015-06-171-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This used to be in platform init code. We want it to do in the driver now. This is basically a code move and a new compatible added. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: at91: fix code checker warningsCyrille Pitchen2015-06-111-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | buf_len is a size_t, so unsigned, but was tested with '<= 0'. Reported-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: busses: xgene-slimpro: fix incorrect __init declation for probeFeng Kan2015-06-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Fix section mismatch error during kernel build for xgene_slimpro_i2c_probe function. It was incorrectly defined with __init declaration. Signed-off-by: Feng Kan <fkan@apm.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: davinci: Avoid sending to own addressAlexander Sverdlin2015-06-101-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sending a message to own address locks the controller up in very bizarre state, it behaves as slave even if MDR register clearly states master. The controller remains in this state until reset. To avoid unnecessary timeouts simply avoid sending to own address. The controller cannot do this any way. Also, do not enable AAS IRQ, as the slave mode is not supported by the driver and the only possibility to trigger this IRQ is to send to own address. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: davinci: Refactor i2c_davinci_wait_bus_not_busy()Alexander Sverdlin2015-06-101-23/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are several problems in the function: - "to_cnt" variable does nothing - schedule_timeout() call without setting current state does nothing - "allow_sleep" parameter is not really used Refactor the function so that it really tries to wait. In case of timeout try to recover the bus. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: brcmstb: Add Broadcom settop SoC i2c controller driverKamal Dasu2015-06-103-0/+705
| | | | | | | | | | | | | | | | | | | | | | | | | | | Adding support for i2c controller driver for Broadcom settop SoCs. Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> [wsa: removed superfluous owner in platform_driver] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: at91: add support to FIFOsCyrille Pitchen2015-06-101-17/+130
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When FIFOs are available and enabled, the driver now configures the Atmel eXtended DMA Controller to perform word accesses instead of byte accesses when possible. The actual access width depends on the size of the buffer to transmit. To enable FIFO support the "atmel,fifo-size" property must be set properly in the I2C controller node of the device tree. Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: at91: print hardware versionCyrille Pitchen2015-06-101-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The probe() function now prints the hardware version of the I2C controller. Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> [wsa: s/version/hw version/] for clarity] Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: at91: add support for new alternative command modeCyrille Pitchen2015-06-101-20/+101
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The alternative command mode was introduced to simplify the transmission of STOP conditions and to solve timing and latency issues around them. This mode relies on a new register, the Alternative Command Register, which must be set at the same time as the Master Mode Register. This new register was designed to allow simple setup of basic combined transactions built from up to two unitary transactions. Indeed, the ACR is split into two areas, which describe one unitary transaction each. Each area is filled with Data Length 8bit counter, a Direction and a PEC Request bit. The PEC bit is only used in SMBus mode and is not supported by this driver yet. Also when using alternative command mode, the MREAD bit from the Master Mode Register is ignored. Instead the Direction bits from ACR are used to setup the direction, read or write, of each unitary transaction. Finally the 8bit counters must filled with the data length of their respective transaction. Then if only one transaction is to be used, the data length of the second one must be set to zero. At the moment, this driver uses only the first transaction. In addition to MMR and ACR, the Control Register also need to be written to enable the alternative command mode. That's the purpose of its ACMEN bit, which stands for Alternative Command Mode Enable. Note that the alternative command mode is compatible with the use of the Internal Address Register. So combined transactions for eeprom read are actually implemented with the Internal Address Register. This register is written with up to 3 bytes, which are the internal address sent to the slave through the first write transaction. Then the first area of the ACR describe the write transaction to follow, which carries the data to be read from the eeprom. The second area of the ACR is not used so its Data Length 8bit counter is cleared. For each byte sent or received by the device, the Data Length 8bit counter is decremented. When it reaches 0, a STOP condition is automatically sent. Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: at91: use BIT() macro to define register bitsCyrille Pitchen2015-06-101-14/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch just fixes typo before applying later patches which will use register bits with index above 16. Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: at91: fix a race condition when using the DMA controllerCyrille Pitchen2015-06-101-17/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For TX transactions, the TXCOMP bit in the Status Register is cleared when the first data is written into the Transmit Holding Register. In the lines from at91_do_twi_transfer(): at91_twi_write_data_dma(dev); at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP); the TXCOMP interrupt may be enabled before the DMA controller has actually started to write into the THR. In such a case, the TXCOMP bit is still set into the Status Register so the interrupt is triggered immediately. The driver understands that a transaction completion has occurred but this transaction hasn't started yet. Hence the TXCOMP interrupt is no longer enabled by at91_do_twi_transfer() but instead by at91_twi_write_data_dma_callback(). Also, the TXCOMP bit in the Status Register in not a clear on read flag but a snapshot of the transmission state at the time the Status Register is read. When a NACK error is dectected by the I2C controller, the TXCOMP, NACK and TXRDY bits are set together to 1 in the SR. If enabled, the TXCOMP interrupt is triggered at the same time. Also setting the TXRDY to 1 triggers the DMA controller to write the next data into the THR. Such a write resets the TXCOMP bit to 0 in the SR. So depending on when the interrupt handler reads the SR, it may fail to detect the NACK error if it relies on the TXCOMP bit. The NACK bit and its interrupt should be used instead. For RX transactions, the TXCOMP bit in the Status Register is cleared when the START bit is set into the Control Register. However to unify the management of the TXCOMP bit when the DMA controller is used, the TXCOMP interrupt is now enabled by the DMA callbacks for both TX and RX transfers. Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> Cc: stable@vger.kernel.org #3.10 and later Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: iproc: Add suspend/resume supportRay Jui2015-06-031-0/+57
| | | | | | | | | | | | | | | | | | | | | | | | Add suspend/resume support to the Broadcom iProc I2C driver Signed-off-by: Ray Jui <rjui@broadcom.com> Reviewed-by: Scott Branden <sbranden@broadcom.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: designware: Avoid unnecessary resuming during system suspendJisheng Zhang2015-06-031-4/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 1fc2fe204cb9 ("i2c: designware: Add runtime PM hooks") adds runtime pm support using the same ops for system pm and runtime pm. When suspend to ram, the i2c host may have been runtime suspended, thus i2c_dw_disable() hangs. Previously, I fixed this issue by separating ops for system pm and runtime pm, then in the system suspend/resume path, runtime pm apis are used to ensure the device is at correct state. But as Mika Westerberg pointed out: it sounds a bit silly to resume the device just because you want to call i2c_dw_disable() for it before suspending again. He then suggested an elegant solution which keeps the device runtime suspended during system suspend with the help of 'dev->power.direct_complete'. This patch adopted this solution, and in fact Mika provided the main code. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: axxia: Add bus recovery functionalityAlexander Sverdlin2015-06-031-0/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | Use recovery framework and implement bus recovery using "Bus Monitor" register. Tests show that shortening SDA to GND results in "completion" timeout with "BUSY" bit still set, so initiate recovery in this case. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: core: Reduce stack size of acpi_i2c_space_handler()Jarkko Nikula2015-06-031-16/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sizeof(struct i2c_client) is 1088 bytes on a CONFIG_X86_64=y build and produces following warning when CONFIG_FRAME_WARN is set to 1024: drivers/i2c/i2c-core.c: In function ‘acpi_i2c_space_handler’: drivers/i2c/i2c-core.c:367:1: warning: the frame size of 1152 bytes is larger than 1024 bytes [-Wframe-larger-than=] This is not critical given that kernel stack is 16 kB on x86_64 but lets reduce the stack usage by allocating the struct i2c_client from the heap. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: smbus: fix typo in commetShailendra Verma2015-06-011-1/+1
| | | | | | | | | | | | | | | Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: algo-pca: fix typo in commentShailendra Verma2015-06-011-1/+1
| | | | | | | | | | | | | | | Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: core: fix typo in commentShailendra Verma2015-06-011-1/+1
| | | | | | | | | | | | | | | Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | I2C: mediatek: Add driver for MediaTek MT8173 I2C controllerEddie Huang2015-06-011-29/+74
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add mediatek MT8173 I2C controller driver. Compare to I2C controller of earlier mediatek SoC, MT8173 fix write-then-read limitation, and also increase message size to 64kb. Signed-off-by: Xudong Chen <xudong.chen@mediatek.com> Signed-off-by: Liguo Zhang <liguo.zhang@mediatek.com> Signed-off-by: Eddie Huang <eddie.huang@mediatek.com> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | I2C: mediatek: Add driver for MediaTek I2C controllerXudong Chen2015-06-013-0/+696
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mediatek SoCs have I2C controller that handle I2C transfer. This patch include common I2C bus driver. This driver is compatible with I2C controller on mt65xx/mt81xx. Signed-off-by: Xudong Chen <xudong.chen@mediatek.com> Signed-off-by: Liguo Zhang <liguo.zhang@mediatek.com> Signed-off-by: Eddie Huang <eddie.huang@mediatek.com> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: check for proper length of the reg propertyWolfram Sang2015-06-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | int is vague, let's simply use the type of the variable in question. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: slave: add error messages to slave coreWolfram Sang2015-06-011-5/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | Inform users what went wrong from the core, so drivers don't have to do it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: rcar: report slave capabilities to usersWolfram Sang2015-06-011-1/+2
| | | | | | | | | | | | | | | | | | Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-28 05:26:39 +0000