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2015-08-24i2c: core: Add support for best effort block read emulationIrina Tirdea
There are devices that need to handle block transactions regardless of the capabilities exported by the adapter. For performance reasons, they need to use i2c read blocks if available, otherwise emulate the block transaction with word or byte transactions. Add support for a helper function that would read a data block using the best transfer available: I2C_FUNC_SMBUS_READ_I2C_BLOCK, I2C_FUNC_SMBUS_READ_WORD_DATA or I2C_FUNC_SMBUS_READ_BYTE_DATA. Signed-off-by: Irina Tirdea <irina.tirdea@intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-24i2c: add a flag to mark clients as slavesWolfram Sang
And update indentation with one more tab, sigh... Tested-by: Andrey Danin <danindrey@mail.ru> Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: core: add and export of_get_i2c_adapter_by_node() interfaceVladimir Zapolskiy
of_find_i2c_adapter_by_node() call requires quite often missing put_device(), and i2c_put_adapter() releases a device locked by i2c_get_adapter() only. In general module_put(adapter->owner) and put_device(dev) are not interchangeable. This is a common error reproduction scenario as a result of the misusage described above (for clearness this is run on iMX6 platform with HDMI and I2C bus drivers compiled as kernel modules): root@mx6q:~# lsmod | grep i2c i2c_imx 10213 0 root@mx6q:~# lsmod | grep dw_hdmi_imx dw_hdmi_imx 3631 0 dw_hdmi 11846 1 dw_hdmi_imx imxdrm 8674 3 dw_hdmi_imx,imx_ipuv3_crtc,imx_ldb drm_kms_helper 113765 5 dw_hdmi,imxdrm,imx_ipuv3_crtc,imx_ldb root@mx6q:~# rmmod dw_hdmi_imx root@mx6q:~# lsmod | grep i2c i2c_imx 10213 -1 ^^^^^ root@mx6q:~# rmmod i2c_imx rmmod: ERROR: Module i2c_imx is in use To fix existing users of these interfaces and to avoid any further confusion and misusage in future, add one more interface of_get_i2c_adapter_by_node(), it is similar to i2c_get_adapter() in sense that an I2C bus device driver found and locked by user can be correctly unlocked by i2c_put_adapter(). Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-04-14Merge tag 'pm+acpi-4.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI updates from Rafael Wysocki: "These are mostly fixes and cleanups all over, although there are a few items that sort of fall into the new feature category. First off, we have new callbacks for PM domains that should help us to handle some issues related to device initialization in a better way. There also is some consolidation in the unified device properties API area allowing us to use that inferface for accessing data coming from platform initialization code in addition to firmware-provided data. We have some new device/CPU IDs in a few drivers, support for new chips and a new cpufreq driver too. Specifics: - Generic PM domains support update including new PM domain callbacks to handle device initialization better (Russell King, Rafael J Wysocki, Kevin Hilman) - Unified device properties API update including a new mechanism for accessing data provided by platform initialization code (Rafael J Wysocki, Adrian Hunter) - ARM cpuidle update including ARM32/ARM64 handling consolidation (Daniel Lezcano) - intel_idle update including support for the Silvermont Core in the Baytrail SOC and for the Airmont Core in the Cherrytrail and Braswell SOCs (Len Brown, Mathias Krause) - New cpufreq driver for Hisilicon ACPU (Leo Yan) - intel_pstate update including support for the Knights Landing chip (Dasaratharaman Chandramouli, Kristen Carlson Accardi) - QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann) - powernv cpufreq driver update (Shilpasri G Bhat) - devfreq update including Tegra support changes (Tomeu Vizoso, MyungJoo Ham, Chanwoo Choi) - powercap RAPL (Running-Average Power Limit) driver update including support for Intel Broadwell server chips (Jacob Pan, Mathias Krause) - ACPI device enumeration update related to the handling of the special PRP0001 device ID allowing DT-style 'compatible' property to be used for ACPI device identification (Rafael J Wysocki) - ACPI EC driver update including limited _DEP support (Lan Tianyu, Lv Zheng) - ACPI backlight driver update including a new mechanism to allow native backlight handling to be forced on non-Windows 8 systems and a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede) - New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu) - Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger, Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki) - Fixes related to suspend-to-idle for the iTCO watchdog driver and the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu) - PM tracing support for the suspend phase of system suspend/resume transitions (Zhonghui Fu) - Configurable delay for the system suspend/resume testing facility (Brian Norris) - PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki)" * tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits) ACPI / scan: Fix NULL pointer dereference in acpi_companion_match() ACPI / scan: Rework modalias creation when "compatible" is present intel_idle: mark cpu id array as __initconst powercap / RAPL: mark rapl_ids array as __initconst powercap / RAPL: add ID for Broadwell server intel_pstate: Knights Landing support intel_pstate: remove MSR test cpufreq: fix qoriq uniprocessor build ACPI / scan: Take the PRP0001 position in the list of IDs into account ACPI / scan: Simplify acpi_match_device() ACPI / scan: Generalize of_compatible matching device property: Introduce firmware node type for platform data device property: Make it possible to use secondary firmware nodes PM / watchdog: iTCO: stop watchdog during system suspend cpufreq: hisilicon: add acpu driver ACPI / EC: Call acpi_walk_dep_device_list() after installing EC opregion handler cpufreq: powernv: Report cpu frequency throttling intel_idle: Add support for the Airmont Core in the Cherrytrail and Braswell SOCs intel_idle: Update support for Silvermont Core in Baytrail SOC PM / devfreq: tegra: Register governor on module init ...
2015-04-10i2c: change input parameter to i2c_adapter for prepare/unprepare_recoveryGrygorii Strashko
This patch changes type of input parameter for prepare/unprepare_recovery() callbacks from struct i2c_bus_recovery_info * to struct i2c_adapter *. This allows to simplify implementation of these callbacks and avoid type conversations from i2c_bus_recovery_info to i2c_adapter. The i2c_bus_recovery_info can be simply retrieved from struct i2c_adapter which contains pointer on it. There are no users currently, so this is safe to do. Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-27i2c: slave: rework the slave APIWolfram Sang
After more discussion, brave users, and additional datasheet evaluation, some API updates for the new I2C slave framework became imminent. The slave events now get some easier to understand naming. Also, the event handling has been simplified to only need a single call to the slave callback when an action by the backend is required. Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-16driver core / ACPI: Represent ACPI companions using fwnode_handleRafael J. Wysocki
Now that we have struct fwnode_handle, we can use that to point to ACPI companions from struct device objects instead of pointing to struct acpi_device directly. There are two benefits from that. First, the somewhat ugly and hackish struct acpi_dev_node can be dropped and, second, the same struct fwnode_handle pointer can be used in the future to point to other (non-ACPI) firmware device node types. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-13i2c: add quirk structure to describe adapter flawsWolfram Sang
The number of I2C adapters which are not fully I2C compatible is rising, sadly. Drivers usually do handle the flaws, still the user receives only some errno for a transfer which normally can be expected to work. This patch introduces a formal description of flaws. One advantage is that the core can check before the actual transfer if the messages could be transferred at all. This is done in the next patch. Another advantage is that we can pass this information to the user so the restrictions are exactly known and further actions can be based on that. This will be done later after some stabilization period for this description. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Ray Jui <rjui@broadcom.com> Tested-by: Ivan T. Ivanov <iivanov@mm-sol.com> Tested-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com> Tested-By: Ludovic Desroches <ludovic.desroches@atmel.com>
2015-02-21Merge branch 'i2c/for-3.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "Summary: - legacy PM code removed from the core, there were no users anymore (thanks to Lars-Peter Clausen) - new driver for Broadcom iProc - bigger driver updates for designware, rk3x, cadence, ocores - a bunch of smaller updates and bugfixes" * 'i2c/for-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (31 commits) i2c: ocores: rework clk code to handle NULL cookie i2c: designware-baytrail: another fixup for proper Kconfig dependencies i2c: fix reference to functionality constants definition i2c: iproc: Add Broadcom iProc I2C Driver i2c: designware-pci: update Intel copyright line i2c: ocores: add common clock support i2c: hix5hd2: add COMPILE_TEST i2c: clarify comments about the dev_released completion i2c: ocores: fix clock-frequency binding usage i2c: tegra: Maintain CPU endianness i2c: designware-baytrail: use proper Kconfig dependencies i2c: designware: Do not calculate SCL timing parameters needlessly i2c: do not try to load modules for of-registered devices i2c: designware: Add Intel Baytrail PMIC I2C bus support i2c: designware: Add i2c bus locking support of: i2c: Add i2c-mux-idle-disconnect DT property to PCA954x mux driver i2c: designware: use {readl|writel}_relaxed instead of readl/writel i2c: designware-pci: no need to provide clk_khz i2c: designware-pci: remove Moorestown support i2c: imx: whitespace and checkpatch cleanup ...
2015-01-26i2c: Only include slave support if selectedJean Delvare
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 <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-22i2c: Remove support for legacy PMLars-Peter Clausen
There haven't been any I2C driver that use the legacy suspend/resume callbacks for a while now and new drivers are supposed to use PM ops. So remove support for legacy suspend/resume for I2C drivers. Since there aren't any special bus specific things to do during suspend/resume and since the PM core will automatically fallback directly to using the device's PM ops if no bus PM ops are specified there is no need to have any I2C bus PM ops. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-14Merge branch 'i2c/for-3.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "For 3.19, the I2C subsystem has to offer special candy this time. Right in time for Christmas :) - I2C slave framework: finally, a generic mechanism for Linux being an I2C slave (if the bus driver supports that). Docs are still missing but will come later this cycle, the code is good enough to go. - I2C muxes represent their topology in sysfs much more detailed. This will help users to navigate around much easier. - irq population of i2c clients is now done at probe time, not device creation time, to have better support for deferred probing. - new drivers for Imagination SCB, Amlogic Meson - DMA support added for Freescale IMX, Renesas SHMobile - slightly bigger driver updates to OMAP, i801, AT91, and rk3x (mostly quirk handling, timing updates, and using better kernel interfaces) - eeprom driver can now write with byte-access (very slow, but OK to have) - and the bunch of smaller fixes, cleanups, ID updates..." * 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (56 commits) i2c: sh_mobile: remove unneeded DMA mask i2c: rcar: add slave support i2c: slave-eeprom: add eeprom simulator driver i2c: core changes for slave support MAINTAINERS: add I2C dt bindings also to I2C realm i2c: designware: Fix falling time bindings doc i2c: davinci: switch to use platform_get_irq Documentation: i2c: Use PM ops instead of legacy suspend/resume i2c: sh_mobile: optimize irq entry i2c: pxa: add support for SCCB devices omap: i2c: don't check bus state IP rev3.3 and earlier i2c: s3c2410: Handle i2c sys_cfg register in i2c driver i2c: rk3x: add Kconfig dependency on COMMON_CLK i2c: omap: add notes related to i2c multimaster mode i2c: omap: don't reset controller if Arbitration Lost detected i2c: omap: implement workaround for handling invalid BB-bit values i2c: omap: cleanup register definitions i2c: rk3x: handle dynamic clock rate changes correctly i2c: at91: enable probe deferring on dma channel request i2c: at91: remove legacy DMA support ...
2014-12-11i2c: core changes for slave supportWolfram Sang
Finally(!), make Linux support being an I2C slave. Most of the existing infrastructure is reused. We mainly add i2c_slave_register/unregister() calls which tells i2c bus drivers to activate the slave mode. Then, they also get a callback to report slave events to. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-03treewide: Fix typo in Documentation/DocBook/device-driversMasanari Iida
This patch fix speeling typo found in html files within Documentation/DocBook/device-drivers. It is because html files are generated from comments in source, so I have to fix comments in the source. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-09-25i2c: move acpi code back into the coreWolfram Sang
Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed the i2c-core module. This may cause regressions for distributions, so put the ACPI code back into the core. Reported-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Lan Tianyu <tianyu.lan@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-08-19i2c: rework kernel config I2C_ACPILan Tianyu
Commit da3c6647(I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI config) adds a new kernel config I2C_ACPI and make I2C core built in when the config is selected. This is wrong because distributions etc generally compile I2C as a module and the commit broken that. This patch is to rename I2C_ACPI to ACPI_I2C_OPREGION. New config only controls ACPI I2C operation region code and depends on I2C=y. Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> [wsa: removed unrelated change for Kconfig] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-27I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI configLan Tianyu
Clean up ACPI related code in the i2c core and add CONFIG_I2C_ACPI to enable I2C ACPI code. Current there is a race between removing I2C ACPI operation region and ACPI AML code accessing. So make i2c core built-in if CONFIG_I2C_ACPI is set. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-27I2C/ACPI: Add i2c ACPI operation region supportLan Tianyu
ACPI 5.0 spec(5.5.2.4.5) defines GenericSerialBus(i2c, spi, uart) operation region. It allows ACPI aml code able to access such kind of devices to implement some ACPI standard method. ACPI Spec defines some access attribute to associate with i2c protocol. AttribQuick Read/Write Quick Protocol AttribSendReceive Send/Receive Byte Protocol AttribByte Read/Write Byte Protocol AttribWord Read/Write Word Protocol AttribBlock Read/Write Block Protocol AttribBytes Read/Write N-Bytes Protocol AttribProcessCall Process Call Protocol AttribBlockProcessCall Write Block-Read Block Process Call Protocol AttribRawBytes Raw Read/Write N-BytesProtocol AttribRawProcessBytes Raw Process Call Protocol On the Asus T100TA, Bios use GenericSerialBus operation region to access i2c device to get battery info. Sample code From Asus T100TA Scope (_SB.I2C1) { Name (UMPC, ResourceTemplate () { I2cSerialBus (0x0066, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , ) }) ... OperationRegion (DVUM, GenericSerialBus, Zero, 0x0100) Field (DVUM, BufferAcc, NoLock, Preserve) { Connection (UMPC), Offset (0x81), AccessAs (BufferAcc, AttribBytes (0x3E)), FGC0, 8 } ... } Device (BATC) { Name (_HID, EisaId ("PNP0C0A")) // _HID: Hardware ID Name (_UID, One) // _UID: Unique ID ... Method (_BST, 0, NotSerialized) // _BST: Battery Status { If (LEqual (AVBL, One)) { Store (FGC0, BFFG) If (LNotEqual (STAT, One)) { ShiftRight (CHST, 0x04, Local0) And (Local0, 0x03, Local0) If (LOr (LEqual (Local0, One), LEqual (Local0, 0x02))) { Store (0x02, Local1) } ... } The i2c operation region is defined under I2C1 scope. _BST method under battery device BATC read battery status from the field "FCG0". The request would be sent to i2c operation region handler. This patch is to add i2c ACPI operation region support. Due to there are only "Byte" and "Bytes" protocol access on the Asus T100TA, other protocols have not been tested. About RawBytes and RawProcessBytes protocol, they needs specific drivers to interpret reference data from AML code according ACPI 5.0 SPEC(5.5.2.4.5.3.9 and 5.5.2.4.5.3.10). So far, not found such case and will add when find real case. Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-05i2c: add deprecation warning for class based instantiationWolfram Sang
Class based instantiation can cause noticeable delays when booting. This mechanism is used when it is not possible to describe slaves on I2C busses. As we do have other mechanisms, most embedded I2C will not need classes and for embedded it is explicitly not recommended to use them. Add a deprecation warning for drivers which want to disable class based instantiation in the near future to gain boot-up time, so users relying on this technique can switch to something better. They really should. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-26i2c: update i2c_algorithm documentationBen Dooks
Add some kerneldoc style documentaton to the i2c_algorithm structure, and point the master_xfer return codes at the right place in Documentation/i2c/fault_codes Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-14i2c: Re-instate body of i2c_parent_is_i2c_adapter()Stephen Warren
The body of i2c_parent_is_i2c_adapter() is currently guarded by I2C_MUX. It should be CONFIG_I2C_MUX instead. Among potentially other problems, this resulted in i2c_lock_adapter() only locking I2C mux child adapters, and not the parent adapter. In turn, this could allow inter-mingling of mux child selection and I2C transactions, which could result in I2C transactions being directed to the wrong I2C bus, and possibly even switching between busses in the middle of a transaction. One concrete issue caused by this bug was corrupted HDMI EDID reads during boot on the NVIDIA Tegra Seaboard system, although this only became apparent in recent linux-next, when the boot timing was changed just enough to trigger the race condition. Fixes: 3923172b3d70 ("i2c: reduce parent checking to a NOOP in non-I2C_MUX case") Cc: Phil Carmody <phil.carmody@partner.samsung.com> Cc: <stable@vger.kernel.org> Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-03i2c: Remove redundant 'driver' field from the i2c_client structLars-Peter Clausen
The 'driver' field of the i2c_client struct is redundant. The same data can be accessed through to_i2c_driver(client->dev.driver). The generated code for both approaches in more or less the same. E.g. on ARM the expression client->driver->command(...) generates ... ldr r3, [r0, #28] ldr r3, [r3, #32] blx r3 ... and the expression to_i2c_driver(client->dev.driver)->command(...) generates ... ldr r3, [r0, #160] ldr r3, [r3, #-4] blx r3 ... Other architectures will generate similar code. All users of the 'driver' field outside of the I2C core have already been converted. So this only leaves the core itself. This patch converts the remaining few users in the I2C core and then removes the 'driver' field from the i2c_client struct. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23i2c: move ACPI helpers into the coreMika Westerberg
This follows what has already been done for the DeviceTree helpers. Move the ACPI helpers from drivers/acpi/acpi_i2c.c to the I2C core and update documentation accordingly. This also solves a problem reported by Jerry Snitselaar that we can't build the ACPI I2C helpers as a module. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23i2c: move OF helpers into the coreWolfram Sang
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows that it is much cleaner to have this in the core. This also removes a circular dependency between the helpers and the core, and so we can finally register child nodes in the core instead of doing this manually in each driver. So, fix the drivers and documentation, too. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-07i2c: reduce parent checking to a NOOP in non-I2C_MUX casePhil Carmody
In 0826374 - i2c: Multiplexed I2C bus core support core i2c code increased in size and complexity even when I2C_MUX wasn't selected. Turning this check into a constant NULL in the n case lets the client functions in be simplified too, not needing to include never-called calls to the mux-specific helpers. Signed-off-by: Phil Carmody <phil.carmody@partner.samsung.com> 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: 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>
2013-03-24i2c: Add bus recovery infrastructureViresh Kumar
Add i2c bus recovery infrastructure to i2c adapters as specified in the i2c protocol Rev. 03 section 3.1.16 titled "Bus clear". http://www.nxp.com/documents/user_manual/UM10204.pdf Sometimes during operation i2c bus hangs and we need to give dummy clocks to slave device to start the transfer again. Now we may have capability in the bus controller to generate these clocks or platform may have gpio pins which can be toggled to generate dummy clocks. This patch supports both. This patch also adds in generic bus recovery routines gpio or scl line based which can be used by bus controller. In addition controller driver may provide its own version of the bus recovery routine. This doesn't support multi-master recovery for now. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [wsa: changed gpio type to int and minor reformatting] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2012-11-23i2c / ACPI: add ACPI enumeration supportMika Westerberg
ACPI 5 introduced I2cSerialBus resource that makes it possible to enumerate and configure the I2C slave devices behind the I2C controller. This patch adds helper functions to support I2C slave enumeration. An ACPI enabled I2C controller driver only needs to call acpi_i2c_register_devices() in order to get its slave devices enumerated, created and bound to the corresponding ACPI handle. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-13UAPI: (Scripted) Disintegrate include/linuxDavid Howells
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
2012-10-05i2c: Correct struct i2c_driver doc about detectionVivien Didelot
s/address_data/address_list/ in addition to c3813d6. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-30Merge branch 'v4l_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media updates from Mauro Carvalho Chehab: "This is the first part of the media patches for v3.6. This patch series contain: - new DVB frontend: rtl2832 - new video drivers: adv7393 - some unused files got removed - a selection API cleanup between V4L2 and V4L2 subdev API's - a major redesign at v4l-ioctl2, in order to clean it up - several driver fixes and improvements." * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (174 commits) v4l: Export v4l2-common.h in include/linux/Kbuild media: Revert "[media] Terratec Cinergy S2 USB HD Rev.2" [media] media: Use pr_info not homegrown pr_reg macro [media] Terratec Cinergy S2 USB HD Rev.2 [media] v4l: Correct conflicting V4L2 subdev selection API documentation [media] Feature removal: V4L2 selections API target and flag definitions [media] v4l: Unify selection flags documentation [media] v4l: Unify selection flags [media] v4l: Common documentation for selection targets [media] v4l: Unify selection targets across V4L2 and V4L2 subdev interfaces [media] v4l: Remove "_ACTUAL" from subdev selection API target definition names [media] V4L: Remove "_ACTIVE" from the selection target name definitions [media] media: dvb-usb: print mac address via native %pM [media] s5p-tv: Use module_i2c_driver in sii9234_drv.c file [media] media: gpio-ir-recv: add allowed_protos for platform data [media] s5p-jpeg: Use module_platform_driver in jpeg-core.c file [media] saa7134: fix spelling of detach in label [media] cx88-blackbird: replace ioctl by unlocked_ioctl [media] cx88: don't use current_norm [media] cx88: fix a number of v4l2-compliance violations ...
2012-07-24i2c: Add SCCB supportLaurent Pinchart
SCCB is a serial communication bus developed by Omnivision. Its 2-wire mode is very similar to SMBus byte data transactions, but requires the controller to ignore the ACK bit and to insert a stop condition after each message. Add a device SCCB flag and a message stop flag to be passed to controller drivers. [JD: Kill rogue definition in go7007 driver.] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-06-29[media] i2c: Export an unlocked flavor of i2c_transferJean Delvare
Some drivers (in particular for TV cards) need exclusive access to their I2C buses for specific operations. Export an unlocked flavor of i2c_transfer to give them full control. The unlocked flavor has the following limitations: * Obviously, caller must hold the i2c adapter lock. * No debug messages are logged. We don't want to log messages while holding a rt_mutex. * No check is done on the existence of adap->algo->master_xfer. It is thus the caller's responsibility to ensure that the function is OK to call. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-30i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLINGMark Brown
Since there are uses for I2C_M_NOSTART which are much more sensible and standard than most of the protocol mangling functionality (the main one being gather writes to devices where something like a register address needs to be inserted before a block of data) create a new I2C_FUNC_NOSTART for this feature and update all the users to use it. Also strengthen the disrecommendation of the protocol mangling while we're at it. In the case of regmap-i2c we remove the requirement for mangling as I2C_M_NOSTART is the only mangling feature which is being used. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-05-12i2c: implement i2c_verify_adapterStephen Warren
This converts a struct device * to a struct i2c_adapter * while verifying that the device really is an I2C adapter. Just like i2c_verify_client. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-03-26i2c: Update the FSF addressJean Delvare
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-01-06Merge branch 'driver-core-next' into Linux 3.2Greg Kroah-Hartman
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file, and it fixes the build error in the arch/x86/kernel/microcode_core.c file, that the merge did not catch. The microcode_core.c patch was provided by Stephen Rothwell <sfr@canb.auug.org.au> who was invaluable in the merge issues involved with the large sysdev removal process in the driver-core tree. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-23i2c: Delete ANY_I2C_BUSJean Delvare
Last piece of code using ANY_I2C_BUS was deleted almost 2 years ago, so ANY_I2C_BUS can go away as well. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-11-17I2C: Add helper macro for i2c_driver boilerplateLars-Peter Clausen
This patch introduces the module_i2c_driver macro which is a convenience macro for I2C driver modules similar to module_platform_driver. It is intended to be used by drivers which init/exit section does nothing but register/unregister the I2C driver. By using this macro it is possible to eliminate a few lines of boilerplate code per I2C driver. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-31include: replace linux/module.h with "struct module" wherever possiblePaul Gortmaker
The <linux/module.h> pretty much brings in the kitchen sink along with it, so it should be avoided wherever reasonably possible in terms of being included from other commonly used <linux/something.h> files, as it results in a measureable increase on compile times. The worst culprit was probably device.h since it is used everywhere. This file also had an implicit dependency/usage of mutex.h which was masked by module.h, and is also fixed here at the same time. There are over a dozen other headers that simply declare the struct instead of pulling in the whole file, so follow their lead and simply make it a few more. Most of the implicit dependencies on module.h being present by these headers pulling it in have been now weeded out, so we can finally make this change with hopefully minimal breakage. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31include: convert various register fcns to macros to avoid include chainingPaul Gortmaker
The original implementations reference THIS_MODULE in an inline. We could include <linux/export.h>, but it is better to avoid chaining. Fortunately someone else already thought of this, and made a similar inline into a #define in <linux/device.h> for device_schedule_callback(), [see commit 523ded71de0] so follow that precedent here. Also bubble up any __must_check that were used on the prev. wrapper inline functions up one to the real __register functions, to preserve any prev. sanity checks that were used in those instances. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-30i2c: Functions for byte-swapped smbus_write/read_word_dataJonathan Cameron
Reimplemented at least 17 times discounting error mangling cases where it could be used. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-05-25hwmon: (jc42) Change detection classJean Delvare
While the JC42-compatible chips are temperature sensors, I2C_CLASS_SPD makes more sense because these chips always live on memory modules. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Guenter Roeck <guenter.roeck@ericsson.com>
2011-03-20i2c: Drop i2c_adapter.idJean Delvare
There is no user left of i2c_adapter.id, so we can get rid of it. Finally! :) Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: Deprecate i2c_driver.attach_adapter and .detach_adapterJean Delvare
The last legitimate user of i2c_driver.attach_adapter and .detach_adapter is gone, so we can finally deprecate these callbacks. The last few drivers which still use these will have to be updated to make use of standard I2C device instantiation ways instead. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: Export i2c_for_each_devJean Delvare
Introduce i2c_for_each_dev(), an i2c device iterator with proper locking for use by i2c-dev. This is needed so that we can get rid of the attach_adapter and detach_adapter legacy callback functions. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: Get rid of <linux/i2c-id.h>Jean Delvare
The last remaining ID in <linux/i2c-id.h> is no longer used anywhere, so we can finally get rid of it. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: make i2c_get_adapter prototype clearerJean Delvare
Rename the parameter of i2c_get_adapter() to "nr", to make it clear we are passing an adapter number and not an adapter ID (which have gone away by now.) Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-01-21driver-core: remove conditionals around devicetree pointersGrant Likely
Having conditional around the of_match_table and the of_node pointers turns out to make driver code use ugly #ifdef blocks. Drop the conditionals and remove the #ifdef blocks from the affected drivers. Also tidy up minor whitespace issues within the same hunks. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>