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2017-04-03i2c: mux: pinctrl: stop double error reportingPeter Rosin
i2c_mux_add_adapter already logs a message on failure. Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Peter Rosin <peda@axentia.se>
2016-05-04i2c: mux: relax locking of the top i2c adapter during mux-locked muxingPeter Rosin
With a i2c topology like the following GPIO ---| ------ BAT1 | v / I2C -----+----------+---- MUX | \ EEPROM ------ BAT2 there is a locking problem with the GPIO controller since it is a client on the same i2c bus that it muxes. Transfers to the mux clients (e.g. BAT1) will lock the whole i2c bus prior to attempting to switch the mux to the correct i2c segment. In the above case, the GPIO device is an I/O expander with an i2c interface, and since the GPIO subsystem knows nothing (and rightfully so) about the lockless needs of the i2c mux code, this results in a deadlock when the GPIO driver issues i2c transfers to modify the mux. So, observing that while it is needed to have the i2c bus locked during the actual MUX update in order to avoid random garbage on the slave side, it is not strictly a must to have it locked over the whole sequence of a full select-transfer-deselect mux client operation. The mux itself needs to be locked, so transfers to clients behind the mux are serialized, and the mux needs to be stable during all i2c traffic (otherwise individual mux slave segments might see garbage, or worse). Introduce this new locking concept as "mux-locked" muxes, and call the pre-existing mux locking scheme "parent-locked". Modify the i2c mux locking so that muxes that are "mux-locked" locks only the muxes on the parent adapter instead of the whole i2c bus when there is a transfer to the slave side of the mux. This lock serializes transfers to the slave side of the muxes on the parent adapter. Add code to i2c-mux-gpio and i2c-mux-pinctrl that checks if all involved gpio/pinctrl devices have a parent that is an i2c adapter in the same adapter tree that is muxed, and request a "mux-locked mux" if that is the case. Modify the select-transfer-deselect code for "mux-locked" muxes so that each of the select-transfer-deselect ops locks the mux parent adapter individually. Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-24i2c: mux: pinctrl: fix indentation for better readabilityWolfram Sang
smatch rightfully says: drivers/i2c/muxes/i2c-mux-pinctrl.c:175 i2c_mux_pinctrl_probe() warn: inconsistent indenting Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-22i2c: i2c-mux-pinctrl: convert to use an explicit i2c mux corePeter Rosin
Allocate an explicit i2c mux core to handle parent and child adapters etc. Update the select/deselect ops to be in terms of the i2c mux core instead of the child adapter. Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-31i2c: muxes: fix leaked i2c adapter device node referencesVladimir Zapolskiy
Every call of of_parse_phandle() increments user count of found device node, if OF_DYNAMIC is enabled. The change fixes all similar addressed cases in drivers/i2c. Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20i2c: muxes: drop owner assignment from platform_driversWolfram Sang
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>
2014-01-24i2c: delete non-required instances of include <linux/init.h>Paul Gortmaker
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-11-18Merge branch 'i2c/for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c changes from Wolfram Sang: - new drivers for exynos5, bcm kona, and st micro - bigger overhauls for drivers mxs and rcar - typical driver bugfixes, cleanups, improvements - got rid of the superfluous 'driver' member in i2c_client struct This touches a few drivers in other subsystems. All acked. * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits) i2c: bcm-kona: fix error return code in bcm_kona_i2c_probe() i2c: i2c-eg20t: do not print error message in syslog if no ACK received i2c: bcm-kona: Introduce Broadcom I2C Driver i2c: cbus-gpio: Fix device tree binding i2c: wmt: add missing clk_disable_unprepare() on error i2c: designware: add new ACPI IDs i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH i2c: exynos5: Remove incorrect clk_disable_unprepare i2c: i2c-st: Add ST I2C controller i2c: exynos5: add High Speed I2C controller driver i2c: rcar: fixup rcar type naming i2c: scmi: remove some bogus NULL checks i2c: sh_mobile & rcar: Enable the driver on all ARM platforms i2c: sh_mobile: Convert to clk_prepare/unprepare i2c: mux: gpio: use reg value for i2c_add_mux_adapter i2c: mux: gpio: use gpio_set_value_cansleep() i2c: Include linux/of.h header i2c: mxs: Fix PIO mode on i.MX23 i2c: mxs: Rework the PIO mode operation i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller ...
2013-10-30i2c: Include linux/of.h headerSachin Kamat
'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>
2013-10-10i2c: i2c-mux-pinctrl: use deferred probe when adapter not foundWolfram Sang
If it is not there yet, it might appear later. 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>
2013-08-19i2c: use dev_get_platdata()Jingoo Han
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>
2013-01-22i2c: muxes: fix wrong use of sizeof(ptr)Laurent Navet
sizeof when applied to a pointer typed expression gives the size of the pointer The semantic patch that makes this output is available in scripts/coccinelle/misc/noderef.cocci. More information about semantic patching is available at http://coccinelle.lip6.fr/ Signed-off-by: Laurent Navet <laurent.navet@gmail.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-12-22i2c: remove __dev* attributes from subsystemBill Pemberton
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>
2012-11-13i2c-mux-pinctrl: Fix probe error pathGuenter Roeck
When allocating the memory for i2c busses, the code checked the wrong variable and thus never detected if there was a memory error. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-05i2c-mux: Add support for device auto-detectionJean Delvare
Let I2C bus segments behind multiplexers have a class. This allows for device auto-detection on these segments. As long as parent segments don't share the same class, it should be fine. I implemented support in drivers i2c-mux-gpio and i2c-mux-pca954x. I left i2c-mux-pca9541 and i2c-mux-pinctrl alone for the moment as I don't know if this feature makes sense for the use cases of these drivers. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Peter Korsgaard <peter.korsgaard@barco.com> Cc: David Daney <david.daney@cavium.com> Cc: Michael Lawnick <ml.lawnick@gmx.de> Cc: Rodolfo Giometti <giometti@linux.it>
2012-06-04i2c: Add generic I2C multiplexer using pinctrl APIStephen Warren
This is useful for SoCs whose I2C module's signals can be routed to different sets of pins at run-time, using the pinctrl API. +-----+ +-----+ | dev | | dev | +------------------------+ +-----+ +-----+ | SoC | | | | /----|------+--------+ | +---+ +------+ | child bus A, on first set of pins | |I2C|---|Pinmux| | | +---+ +------+ | child bus B, on second set of pins | \----|------+--------+--------+ | | | | | +------------------------+ +-----+ +-----+ +-----+ | dev | | dev | | dev | +-----+ +-----+ +-----+ Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>