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path: root/drivers/i2c/busses/i2c-gpio.c
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2022-12-05i2c: gpio: Fix potential unused warning for 'i2c_gpio_dt_ids'Binbin Zhou1-3/+1
Dropping a matching #ifdef check along with dropping of_match_ptr() is just a cleanup, while dropping of_match_ptr() that has no corresponding #ifdef fixes an actual warning. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-08-11i2c: move drivers from strlcpy to strscpyWolfram Sang1-1/+1
Follow the advice of the below link and prefer 'strscpy'. Conversion is easy because no driver used the return value and has been done with a simple sed invocation. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-01-05i2c: gpio: fix MODULE_LICENCEWolfram Sang1-1/+1
Let MODULE_LICENCE match the SPDX header which is correctly based on the previous textual description. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-03-10i2c: gpio: suppress error on probe deferHamish Martin1-1/+1
If a GPIO we are trying to use is not available and we are deferring the probe, don't output an error message. This seems to have been the intent of commit 05c74778858d ("i2c: gpio: Add support for named gpios in DT") but the error was still output due to not checking the updated 'retdesc'. Fixes: 05c74778858d ("i2c: gpio: Add support for named gpios in DT") Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16i2c: gpio: flag atomic capability if possibleWolfram Sang1-0/+2
If switching GPIOs does not sleep, then we can support atomic transfers. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: gpio: fault-injector: add 'inject_panic' injectorWolfram Sang1-1/+30
Add a fault injector simulating a Kernel panic happening after starting a transfer. Read the docs for its usage. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: gpio: fault-injector: add 'lose_arbitration' injectorWolfram Sang1-0/+74
Add a fault injector simulating 'arbitration lost' from multi-master setups. Read the docs for its usage. A helper function for future fault injectors using SCL interrupts is created to achieve this. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08i2c: gpio: merge two very similar commentsWolfram Sang1-12/+5
I think it is clear enough if we have the explanation once and make it clear it is applicable for both SCL and SDA. Reword it a little with the help of Simon's native language skills :) Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: gpio: fault-injector: sort debugfs files alphabeticallyWolfram Sang1-2/+2
There is no value in chronological sorting. Make it easier to follow for humans. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: gpio: sort includesWolfram Sang1-5/+5
Less risk for duplications when adding new ones. 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>
2018-07-13Merge branch 'i2c/precise-locking-names_immutable' into i2c/for-4.19Wolfram Sang1-20/+20
2018-07-13i2c: remove i2c_lock_adapter and use i2c_lock_bus directlyPeter Rosin1-20/+20
The i2c_lock_adapter name is ambiguous since it is unclear if it refers to the root adapter or the adapter you name in the argument. The natural interpretation is the adapter you name in the argument, but there are historical reasons for that not being the case; it in fact locks the root adapter. Just remove the function and force users to spell out the I2C_LOCK_ROOT_ADAPTER name to indicate what is really going on. Also remove i2c_unlock_adapter, of course. This patch was generated with git grep -l 'i2c_\(un\)\?lock_adapter' \ | xargs sed -i 's/i2c_\(un\)\?lock_adapter(\([^)]*\))/'\ 'i2c_\1lock_bus(\2, I2C_LOCK_ROOT_ADAPTER)/g' followed by white-space touch-up. Signed-off-by: Peter Rosin <peda@axentia.se> Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com> Tested-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: gpio: fault-injector: add incomplete_write_byteWolfram Sang1-0/+21
Add another injector for an incomplete transfer. As mentioned in the docs, this one is important to check bus recovery algorithms with it. Otherwise random data may be sent to devices! Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: gpio: fault-injector: refactor incomplete transferWolfram Sang1-14/+22
Make the incomplete_transfer routine reusable, so we can add other test cases with different patterns later. Prepare the docs for that, too. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-06-29i2c: gpio: initialize SCL to HIGH againWolfram Sang1-2/+2
It seems that during the conversion from gpio* to gpiod*, the initial state of SCL was wrongly switched to LOW. Fix it to be HIGH again. Fixes: 7bb75029ef34 ("i2c: gpio: Enforce open drain through gpiolib") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2018-05-17i2c: gpio: move header to platform_dataWolfram Sang1-1/+1
This header only contains platform_data. Move it to the proper directory. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Lee Jones <lee.jones@linaro.org> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: James Hogan <jhogan@kernel.org> Acked-by: Greg Ungerer <gerg@uclinux.org>
2018-01-04i2c: gpio: Enable working over slow can_sleep GPIOsJan Kundrát1-4/+7
"Slow" GPIOs (usually those connected over an SPI or an I2C bus) are, well, slow in their operation. It is generally a good idea to avoid using them for time-critical operation, but sometimes the hardware just sucks, and the software has to cope. In addition to that, the I2C bus itself does not actually define any strict timing limits; the bus is free to go all the way down to DC. The timeouts (and therefore the slowest acceptable frequency) are present only in SMBus. The `can_sleep` is IMHO a wrong concept to use here. My SPI-to-quad-UART chip (MAX14830) is connected via a 26MHz SPI bus, and it happily drives SCL at 200kHz (5µs pulses) during my benchmarks. That's faster than the maximal allowed speed of the traditional I2C. The previous version of this code did not really block operation over slow GPIO pins, anyway. Instead, it just resorted to printing a warning with a backtrace each time a GPIO pin was accessed, thereby slowing things down even more. Finally, it's not just me. A similar patch was originally submitted in 2015 [1]. [1] https://patchwork.ozlabs.org/patch/450956/ Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03i2c: gpio: add fault injectorWolfram Sang1-0/+111
Add fault injection capabilities to the i2c-gpio driver. When connected to another I2C bus, it can create unusual states which the other I2C bus master driver needs to handle. Only for debugging! Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2017-10-30i2c: gpio: Add support for named gpios in DTLinus Walleij1-16/+43
This adds support for using the "sda" and "scl" GPIOs in device tree instead of anonymously using index 0 and 1 of the "gpios" property. We add a helper function to retrieve the GPIO descriptors and some explicit error handling since the probe may have to be deferred. At least this happened to me when moving to using named "sda" and "scl" lines (all of a sudden this started to probe before the GPIO driver) so we need to gracefully defer probe when we ge -ENOENT in the error pointer. Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-30i2c: gpio: Local vars in probeLinus Walleij1-13/+14
By creating local variables for *dev and *np, the code become much easier to read, in my opinion. Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-30i2c: gpio: Enforce open drain through gpiolibLinus Walleij1-63/+39
The I2C GPIO bitbang driver currently emulates open drain behaviour by implementing what the gpiolib already does: not actively driving the line high, instead setting it to input. This makes no sense. Use the new facility in gpiolib to request the lines enforced into open drain mode, and let the open drain emulation already present in the gpiolib kick in and handle this. As a bonus: if the GPIO driver in the back-end actually supports open drain in hardware using the .set_config() callback, it will be utilized. That's correct: we never used that hardware feature before, instead relying on emulating open drain even if the GPIO controller could actually handle this for us. Users will sometimes get messages like this: gpio-485 (?): enforced open drain please flag it properly in DT/ACPI DSDT/board file gpio-486 (?): enforced open drain please flag it properly in DT/ACPI DSDT/board file i2c-gpio gpio-i2c: using lines 485 (SDA) and 486 (SCL) Which is completely proper: since the line is used as open drain, it should actually be flagged properly with e.g. gpios = <&gpio0 5 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>, <&gpio0 6 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>; Or similar facilities in board file descriptor tables or ACPI DSDT. Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-30i2c: gpio: Convert to use descriptorsLinus Walleij1-71/+63
This converts the GPIO-based I2C-driver to using GPIO descriptors instead of the old global numberspace-based GPIO interface. We: - Convert the driver to unconditionally grab two GPIOs from the device by index 0 (SDA) and 1 (SCL) which will work fine with device tree and descriptor tables. The existing device trees will continue to work just like before, but without any roundtrip through the global numberspace. - Brutally convert all boardfiles still passing global GPIOs by registering descriptor tables associated with the devices instead so this driver does not need to keep supporting passing any GPIO numbers as platform data. There is no stepwise approach as elegant as this, I strongly prefer this big hammer over any antsteps for this conversion. This way the old GPIO numbers go away and NEVER COME BACK. Special conversion for the different boards utilizing I2C-GPIO: - EP93xx (arch/arm/mach-ep93xx): pretty straight forward as all boards were using the same two GPIO lines, just define these two in a lookup table for "i2c-gpio" and register these along with the device. None of them define any other platform data so just pass NULL as platform data. This platform selects GPIOLIB so all should be smooth. The pins appear on a gpiochip for bank "G" as pins 1 (SDA) and 0 (SCL). - IXP4 (arch/arm/mach-ixp4): descriptor tables have to be registered for each board separately. They all use "IXP4XX_GPIO_CHIP" so it is pretty straight forward. Most board define no other platform data than SCL/SDA so they can drop the #include of <linux/i2c-gpio.h> and assign NULL to platform data. The "goramo_mlr" (Goramo Multilink Router) board is a bit worrisome: it implements its own I2C bit-banging in the board file, and optionally registers an I2C serial port, but claims the same GPIO lines for itself in the board file. This is not going to work: there will be competition for the GPIO lines, so delete the optional extra I2C bus instead, no I2C devices are registered on it anyway, there are just hints that it may contain an EEPROM that may be accessed from userspace. This needs to be fixed up properly by the serial clock using I2C emulation so drop a note in the code. - KS8695 board acs5k (arch/arm/mach-ks8695/board-acs5.c) has some platform data in addition to the pins so it needs to be kept around sans GPIO lines. Its GPIO chip is named "KS8695" and the arch selects GPIOLIB. - PXA boards (arch/arm/mach-pxa/*) use some of the platform data so it needs to be preserved here. The viper board even registers two GPIO I2Cs. The gpiochip is named "gpio-pxa" and the arch selects GPIOLIB. - SA1100 Simpad (arch/arm/mach-sa1100/simpad.c) defines a GPIO I2C bus, and the arch selects GPIOLIB. - Blackfin boards (arch/blackfin/bf533 etc) for these I assume their I2C GPIOs refer to the local gpiochip defined in arch/blackfin/kernel/bfin_gpio.c names "BFIN-GPIO". The arch selects GPIOLIB. The boards get spiked with IF_ENABLED(I2C_GPIO) but that is a side effect of it being like that already (I would just have Kconfig select I2C_GPIO and get rid of them all.) I also delete any platform data set to 0 as it will get that value anyway from static declartions of platform data. - The MIPS selects GPIOLIB and the Alchemy machine is using two local GPIO chips, one of them has a GPIO I2C. We need to adjust the local offset from the global number space here. The ATH79 has a proper GPIO driver in drivers/gpio/gpio-ath79.c and AFAICT the chip is named "ath79-gpio" and the PB44 PCF857x expander spawns from this on GPIO 1 and 0. The latter board only use the platform data to specify pins so it can be cut altogether after this. - The MFD Silicon Motion SM501 is a special case. It dynamically spawns an I2C bus off the MFD using sm501_create_subdev(). We use an approach to dynamically create a machine descriptor table and attach this to the "SM501-LOW" or "SM501-HIGH" gpiochip. We use chip-local offsets to grab the right lines. We can get rid of two local static inline helpers as part of this refactoring. Cc: Steven Miao <realmz6@gmail.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Ben Dooks <ben.dooks@codethink.co.uk> Cc: Heiko Schocher <hs@denx.de> Acked-by: Wu, Aaron <Aaron.Wu@analog.com> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Lee Jones <lee.jones@linaro.org> Acked-by: Ralf Baechle <ralf@linux-mips.org> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-07-31i2c: Convert to using %pOF instead of full_nameRob Herring1-2/+2
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20i2c: busses: drop owner assignment from platform_driversWolfram Sang1-1/+0
A platform_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-01i2c: gpio: Drop dead code in i2c_gpio_removeJean Delvare1-2/+0
Commit a0682a31 ("i2c: gpio: Use devm_gpio_request()") left unused code behind, clean it up. Fixes: a0682a315889 ("i2c: gpio: Use devm_gpio_request()") Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-05-22i2c: gpio: Use devm_gpio_request()Jingoo Han1-18/+7
Use devm_gpio_request() to make cleanup paths simpler. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Reviewed-by: Violeta Menendez <violeta.menendez@codethink.co.uk> Reviewed-by: Ian Molton <ian.molton@codethink.co.uk> Tested-by: Violeta Menendez <violeta.menendez@codethink.co.uk> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-13i2c: gpio: OF gpio code does not handle defered probe caseBen Dooks1-0/+3
When using device-tree and the i2c-gpio driver is called before the GPIO node has been probed then it needs to correctly defer the probe instead of returning a permanent error that the gpio numbers are not valid. This fixes the following error: /i2c@2: invalid GPIO pins, sda=-517/scl=-517 Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-30i2c: Include linux/of.h headerSachin Kamat1-0/+1
'of_match_ptr' is defined in linux/of.h. Include it explicitly to avoid build breakage in the future. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23i2c: move OF helpers into the coreWolfram Sang1-3/+0
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>
2013-08-19i2c: use dev_get_platdata()Jingoo Han1-3/+3
Use the wrapper function for retrieving the platform data instead of accessing dev->platform_data directly. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-27i2c: gpio: Add support for deferred probingJean Delvare1-25/+50
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>
2012-12-22i2c: remove __dev* attributes from subsystemBill Pemberton1-4/+4
CONFIG_HOTPLUG is going away as an option. As result the __dev* markings will be going away. Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio) Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio) Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3) Acked-by: Barry Song <baohua.song@csr.com> (for sirf) Reviewed-by: Jean Delvare <khali@linux-fr.org> [wsa: Fixed "foo* bar" flaws while we are here] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-11-14i2c: i2c-gpio: fix name issue with multiple i2c gpio nodesBo Shen1-1/+5
When having multiple i2c-gpio nodes, the name for each is same. So add the patch to fix it. The adap->name printing information was added by myself without this patch the log information is as following ---<8--- adap->name = i2c-gpio-1 i2c-gpio i2c.2: using pins 30 (SDA) and 31 (SCL) adap->name = i2c-gpio-1 i2c-gpio i2c.3: using pins 64 (SDA) and 65 (SCL) --->8--- with this patch, the log information is as following ---<8--- adap->name = i2c.2 i2c-gpio i2c.2: using pins 30 (SDA) and 31 (SCL) adap->name = i2c.3 i2c-gpio i2c.3: using pins 64 (SDA) and 65 (SCL) --->8--- Signed-off-by: Bo Shen <voice.shen@atmel.com> Reviewed-by: Stephen Warren <swarren@nvidia.com> [wsa: minor fixes to the commit mesage] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-05-12i2c: Dynamically assign adapter id if it wasn't explictly specifiedKarol Lewandowski1-6/+1
Commit 488bf314b ("i2c: Allow i2c_add_numbered_adapter() to assign a bus id") reworked i2c_add_numbered_adapter() to call i2c_add_adapter() if requested bus was -1. This allows to simplify driver's initialization procedure by using just one function for static and dynamic adapter id registration. This patch updates few more drivers (missed out in original patch) to use this functionality. Signed-off-by: Karol Lewandowski <k.lewandowsk@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-03-15i2c/gpio: add DT supportJean-Christophe PLAGNIOL-VILLARD1-22/+76
To achieve DT support, we need to populate a custom platform_data in a private struct from DT information. To simplify code, the adapter and algorithm are also put into the private struct. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
2011-05-18Haavard Skinnemoen has left AtmelJean Delvare1-1/+1
Haavard's e-mail address at Atmel is no longer valid. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-05-21i2c-gpio: Move initialization code to subsys_initcall()Marek Szyprowski1-1/+1
GPIO driven I2C bus can be used for controlling the PMIC chip. The example of such configuration is Samsung Aquila board. This patch moves initialization code to subsys_initcall() to ensure that the i2c bus is available early so the regulators can be quickly probed and available for other devices on their probe() call. Such solution has been proposed by Mark Brown to fix the problem of the regulators not beeing available on the peripheral device probe(): http://lists.infradead.org/pipermail/linux-arm-kernel/2010-March/011971.html Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2008-07-28i2c: i2c_gpio: keep probe resident for hotplugged devices.Ben Dooks1-4/+5
Change the i2c_gpio driver to use platform_driver_register() instead of platform_driver_probe() to ensure that is can attach to any devices that may be loaded after it has initialised. Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-14i2c: Let bus drivers add SPD to their classJean Delvare1-1/+1
Let general purpose I2C/SMBus bus drivers add SPD to their class. Once this is done, we will be able to tell the eeprom driver to only probe for SPD EEPROMs and similar on these buses. Note that I took a conservative approach here, adding I2C_CLASS_SPD to many drivers that have no idea whether they can host SPD EEPROMs or not. This is to make sure that the eeprom driver doesn't stop probing buses where SPD EEPROMs or equivalent live. So, bus driver maintainers and users should feel free to remove the SPD class from drivers those buses never have SPD EEPROMs or they don't want the eeprom driver to bind to them. Likewise, feel free to add the SPD class to any bus driver I might have missed. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-04-22i2c: Fix platform driver hotplug/coldplugKay Sievers1-0/+1
Since 43cc71eed1250755986da4c0f9898f9a635cb3bf, the platform modalias is prefixed with "platform:". Add MODULE_ALIAS() to the hotpluggable I2C platform drivers, to allow module auto loading. [ db: add some more drivers ] Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-12-12i2c-gpio: Initialize adapter classAtsushi Nemoto1-0/+1
This is required to let hwmon drivers attach to the adapter. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-09-09i2c-gpio: Fix adapter numberDavid Brownell1-1/+1
It turns out that platform_device.id is a "u32" so testing it for being nonnegative is useless when setting up an i2c bitbang device. Instead, do what the platform_bus code does and test it against the value "-1". Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-07-12i2c-gpio: Make some internal functions staticAtsushi Nemoto1-2/+2
i2c_gpio_getsda() and i2c_gpio_getscl() are only used in this file. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-07-12i2c-gpio: Add support for new-style clientsAtsushi Nemoto1-1/+7
Use i2c_bit_add_numbered_bus() so that the i2c-gpio adapter works well with new-style pre-declared devices. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01i2c: Bitbanging I2C bus driver using the GPIO APIHaavard Skinnemoen1-0/+215
This is a very simple bitbanging I2C bus driver utilizing the new arch-neutral GPIO API. Useful for chips that don't have a built-in I2C controller, additional I2C busses, or testing purposes. To use, include something similar to the following in the board-specific setup code: #include <linux/i2c-gpio.h> static struct i2c_gpio_platform_data i2c_gpio_data = { .sda_pin = GPIO_PIN_FOO, .scl_pin = GPIO_PIN_BAR, }; static struct platform_device i2c_gpio_device = { .name = "i2c-gpio", .id = 0, .dev = { .platform_data = &i2c_gpio_data, }, }; Register this platform_device, set up the I2C pins as GPIO if required and you're ready to go. This will use default values for udelay and timeout, and will work with GPIO hardware that does not support open drain mode, but allows sensing of the SDA and SCL lines even when they are being driven. Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>