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2023-08-30Merge tag 'soc-arm-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/socLinus Torvalds
Pull ARM SoC cleanups from Arnd Bergmann: "These are all minor cleanups for platform specific code in arch/arm/ and some of the associated drivers. The majority of these are work done by Rob Herring to improve the way devicetreee header files are handled" * tag 'soc-arm-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (49 commits) ARM: davinci: Drop unused includes ARM: s5pv210: Explicitly include correct DT includes ARM: dove: Drop unused includes ARM: mvebu: Explicitly include correct DT includes Documentation/process: maintainer-soc: document dtbs_check requirement for Samsung MAINTAINER: samsung: document dtbs_check requirement for Samsung Documentation/process: maintainer-soc: add clean platforms profile MAINTAINERS: soc: reference maintainer profile ARM: nspire: Remove unused header file mmio.h ARM: nspire: Use syscon-reboot to handle restart soc: fsl: Explicitly include correct DT includes soc: xilinx: Explicitly include correct DT includes soc: sunxi: Explicitly include correct DT includes soc: rockchip: Explicitly include correct DT includes soc: mediatek: Explicitly include correct DT includes soc: aspeed: Explicitly include correct DT includes firmware: Explicitly include correct DT includes bus: Explicitly include correct DT includes ARM: spear: Explicitly include correct DT includes ARM: mvebu: Explicitly include correct DT includes ...
2023-08-12bus: Explicitly include correct DT includesRob Herring
The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Link: https://lore.kernel.org/r/20230803-dt-header-cleanups-for-soc-v2-16-d8de2cc88bff@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-07-31bus: sunxi-rsb: Convert to devm_platform_ioremap_resource()Yangtao Li
Use devm_platform_ioremap_resource() to simplify code. Signed-off-by: Yangtao Li <frank.li@vivo.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Link: https://lore.kernel.org/r/20230706072042.31296-1-frank.li@vivo.com Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
2023-02-24Merge tag 'driver-core-6.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.3-rc1. There's a lot of changes this development cycle, most of the work falls into two different categories: - fw_devlink fixes and updates. This has gone through numerous review cycles and lots of review and testing by lots of different devices. Hopefully all should be good now, and Saravana will be keeping a watch for any potential regression on odd embedded systems. - driver core changes to work to make struct bus_type able to be moved into read-only memory (i.e. const) The recent work with Rust has pointed out a number of areas in the driver core where we are passing around and working with structures that really do not have to be dynamic at all, and they should be able to be read-only making things safer overall. This is the contuation of that work (started last release with kobject changes) in moving struct bus_type to be constant. We didn't quite make it for this release, but the remaining patches will be finished up for the release after this one, but the groundwork has been laid for this effort. Other than that we have in here: - debugfs memory leak fixes in some subsystems - error path cleanups and fixes for some never-able-to-be-hit codepaths. - cacheinfo rework and fixes - Other tiny fixes, full details are in the shortlog All of these have been in linux-next for a while with no reported problems" [ Geert Uytterhoeven points out that that last sentence isn't true, and that there's a pending report that has a fix that is queued up - Linus ] * tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (124 commits) debugfs: drop inline constant formatting for ERR_PTR(-ERROR) OPP: fix error checking in opp_migrate_dentry() debugfs: update comment of debugfs_rename() i3c: fix device.h kernel-doc warnings dma-mapping: no need to pass a bus_type into get_arch_dma_ops() driver core: class: move EXPORT_SYMBOL_GPL() lines to the correct place Revert "driver core: add error handling for devtmpfs_create_node()" Revert "devtmpfs: add debug info to handle()" Revert "devtmpfs: remove return value of devtmpfs_delete_node()" driver core: cpu: don't hand-override the uevent bus_type callback. devtmpfs: remove return value of devtmpfs_delete_node() devtmpfs: add debug info to handle() driver core: add error handling for devtmpfs_create_node() driver core: bus: update my copyright notice driver core: bus: add bus_get_dev_root() function driver core: bus: constify bus_unregister() driver core: bus: constify some internal functions driver core: bus: constify bus_get_kset() driver core: bus: constify bus_register/unregister_notifier() driver core: remove private pointer from struct bus_type ...
2023-01-27driver core: make struct bus_type.uevent() take a const *Greg Kroah-Hartman
The uevent() callback in struct bus_type should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Acked-by: Rafael J. Wysocki <rafael@kernel.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-27of: device: make of_device_uevent_modalias() take a const device *Greg Kroah-Hartman
of_device_uevent_modalias() does not modify the device pointer passed to it, so mark it constant. In order to properly do this, a number of busses need to have a modalias function added as they were attempting to just point to of_device_uevent_modalias instead of their bus-specific modalias function. This is fine except if the prototype for a bus and device type modalias function diverges and then problems could happen. To prevent all of that, just wrap the call to of_device_uevent_modalias() directly for each bus and device type individually. Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Chen-Yu Tsai <wens@csie.org> Cc: Jernej Skrabec <jernej.skrabec@gmail.com> Cc: Samuel Holland <samuel@sholland.org> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Liang He <windhl@126.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Lyude Paul <lyude@redhat.com> Cc: Corentin Labbe <clabbe@baylibre.com> Cc: Zou Wei <zou_wei@huawei.com> Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-sunxi@lists.linux.dev Cc: dri-devel@lists.freedesktop.org Cc: devicetree@vger.kernel.org Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230111113018.459199-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-08bus: sunxi-rsb: Fix error handling in sunxi_rsb_init()Yuan Can
The sunxi_rsb_init() returns the platform_driver_register() directly without checking its return value, if platform_driver_register() failed, the sunxi_rsb_bus is not unregistered. Fix by unregister sunxi_rsb_bus when platform_driver_register() failed. Fixes: d787dcdb9c8f ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus") Signed-off-by: Yuan Can <yuancan@huawei.com> Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com> Link: https://lore.kernel.org/r/20221123094200.12036-1-yuancan@huawei.com Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
2022-11-16bus: sunxi-rsb: Support atomic transfersSamuel Holland
When communicating with a PMIC during system poweroff (pm_power_off()), IRQs are disabled and we are in a RCU read-side critical section, so we cannot use wait_for_completion_io_timeout(). Instead, poll the status register for transfer completion. Fixes: d787dcdb9c8f ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus") Signed-off-by: Samuel Holland <samuel@sholland.org> Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com> Link: https://lore.kernel.org/r/20221114015749.28490-3-samuel@sholland.org Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
2022-11-16bus: sunxi-rsb: Remove the shutdown callbackSamuel Holland
Shutting down the RSB controller prevents communicating with a PMIC inside pm_power_off(), since that gets called after device_shutdown(), so it breaks system poweroff on some boards. Reported-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Fixes: 843107498f91 ("bus: sunxi-rsb: Implement suspend/resume/shutdown callbacks") Signed-off-by: Samuel Holland <samuel@sholland.org> Link: https://lore.kernel.org/r/20221114015749.28490-2-samuel@sholland.org Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
2022-06-10treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_56.RULE ↵Thomas Gleixner
(part 2) Based on the normalized pattern: this file is licensed under the terms of the gnu general public license version 2 this program is licensed as is without any warranty of any kind whether express or implied extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-25bus: sunxi-rsb: Fix the return value of sunxi_rsb_device_create()Christophe JAILLET
This code is really spurious. It always returns an ERR_PTR, even when err is known to be 0 and calls put_device() after a successful device_register() call. It is likely that the return statement in the normal path is missing. Add 'return rdev;' to fix it. Fixes: d787dcdb9c8f ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Samuel Holland <samuel@sholland.org> Tested-by: Samuel Holland <samuel@sholland.org> Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com> Link: https://lore.kernel.org/r/ef2b9576350bba4c8e05e669e9535e9e2a415763.1650551719.git.christophe.jaillet@wanadoo.fr
2021-11-22bus: sunxi-rsb: Fix shutdownJernej Skrabec
Function sunxi_rsb_hw_exit() is sometimes called with pm runtime disabled, so in such cases pm_runtime_resume() will fail with -EACCES. Instead of doing whole dance of enabling pm runtime and thus clock just to disable it again immediately, just check if disabling clock is needed. That way calling pm_runtime_resume() is not needed at all. Fixes: 4a0dbc12e618 ("bus: sunxi-rsb: Implement runtime power management") Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20211121083537.612473-1-jernej.skrabec@gmail.com
2021-07-21bus: Make remove callback return voidUwe Kleine-König
The driver core ignores the return value of this callback because there is only little it can do when a device disappears. This is the final bit of a long lasting cleanup quest where several buses were converted to also return void from their remove callback. Additionally some resource leaks were fixed that were caused by drivers returning an error code in the expectation that the driver won't go away. With struct bus_type::remove returning void it's prevented that newly implemented buses return an ignored error code and so don't anticipate wrong expectations for driver authors. Reviewed-by: Tom Rix <trix@redhat.com> (For fpga) Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio) Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts) Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb) Acked-by: Pali Rohár <pali@kernel.org> Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media) Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform) Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-By: Vinod Koul <vkoul@kernel.org> Acked-by: Juergen Gross <jgross@suse.com> (For xen) Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd) Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb) Acked-by: Johan Hovold <johan@kernel.org> Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus) Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio) Acked-by: Maximilian Luz <luzmaximilian@gmail.com> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec) Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack) Acked-by: Geoff Levand <geoff@infradead.org> (For ps3) Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt) Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th) Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia) Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI) Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr) Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid) Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM) Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa) Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire) Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid) Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox) Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss) Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC) Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Finn Thain <fthain@linux-m68k.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-18Merge remote-tracking branch 'mfd/ib-mfd-bus-5.12' into sunxi/drivers-for-5.12Chen-Yu Tsai
2021-01-15mfd/bus: sunxi-rsb: Make .remove() callback return voidUwe Kleine-König
The driver core ignores the return value of struct device_driver::remove because there is only little that can be done. To simplify the quest to make this function return void, let struct sunxi_rsb_driver::remove return void, too. All users already unconditionally return 0, this commit makes this obvious and ensures future users don't behave differently. To simplify even further, make axp20x_device_remove() return void instead of returning 0 unconditionally, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2021-01-06bus: sunxi-rsb: Implement runtime power managementSamuel Holland
Gate the clock to save power while the controller is idle. Signed-off-by: Samuel Holland <samuel@sholland.org> Acked-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2021-01-06bus: sunxi-rsb: Implement suspend/resume/shutdown callbacksSamuel Holland
Since system firmware is likely to use the RSB bus to communicate with a PMIC while the system is suspended, we cannot make any assumptions about the controller state after resuming. Thus it is important to completely reinitialize the controller. The RSB bus needs to be ready as soon as IRQs are enabled, to handle wakeup event IRQs coming from the PMIC. Thus it uses NOIRQ callbacks. Signed-off-by: Samuel Holland <samuel@sholland.org> Acked-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2021-01-06bus: sunxi-rsb: Split out controller init/exit functionsSamuel Holland
This separates the resource acquisition from the hardware initialization phase, so the hardware initialization can be repeated after system suspend/resume. The same is done for the exit/remove function, except that there is no resource deallocation phase due to the use of devres. The requested RSB clock frequency is stored in `struct sunxi_rsb` so it will be available when reinitializing the hardware. Signed-off-by: Samuel Holland <samuel@sholland.org> Acked-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2021-01-06bus: sunxi-rsb: Move OF match tableSamuel Holland
For some reason, this driver's OF match table was placed above the probe/remove functions, far away from the platform_driver definition. Adding device PM ops would move the table even farther away. Let's move it to the usual place, right before the platform_driver. Signed-off-by: Samuel Holland <samuel@sholland.org> Acked-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2020-02-24bus: sunxi-rsb: Return correct data when mixing 16-bit and 8-bit readsOndrej Jirman
When doing a 16-bit read that returns data in the MSB byte, the RSB_DATA register will keep the MSB byte unchanged when doing the following 8-bit read. sunxi_rsb_read() will then return a result that contains high byte from 16-bit read mixed with the 8-bit result. The consequence is that after this happens the PMIC's regmap will look like this: (0x33 is the high byte from the 16-bit read) % cat /sys/kernel/debug/regmap/sunxi-rsb-3a3/registers 00: 33 01: 33 02: 33 03: 33 04: 33 05: 33 06: 33 07: 33 08: 33 09: 33 0a: 33 0b: 33 0c: 33 0d: 33 0e: 33 [snip] Fix this by masking the result of the read with the correct mask based on the size of the read. There are no 16-bit users in the mainline kernel, so this doesn't need to get into the stable tree. Signed-off-by: Ondrej Jirman <megous@megous.com> Acked-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Maxime Ripard <maxime@cerno.tech>
2019-08-06bus: sunxi-rsb: Remove dev_err() usage after platform_get_irq()Stephen Boyd
We don't need dev_err() messages when platform_get_irq() fails now that platform_get_irq() prints an error message itself when something goes wrong. Let's remove these prints with a simple semantic patch. // <smpl> @@ expression ret; struct platform_device *E; @@ ret = ( platform_get_irq(E, ...) | platform_get_irq_byname(E, ...) ); if ( \( ret < 0 \| ret <= 0 \) ) { ( -if (ret != -EPROBE_DEFER) -{ ... -dev_err(...); -... } | ... -dev_err(...); ) ... } // </smpl> While we're here, remove braces on if statements that only have one statement (manually). Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2017-12-05sunxi-rsb: Include OF based modalias in device ueventStefan Brüns
Include the OF-based modalias in the uevent sent when registering devices on the sunxi RSB bus, so that user space has a chance to autoload the kernel module for the device. Fixes a regression caused by commit 3f241bfa60bd ("arm64: allwinner: a64: pine64: Use dcdc1 regulator for mmc0"). When the axp20x-rsb module for the AXP803 PMIC is built as a module, it is not loaded and the system ends up with an disfunctional MMC controller. Fixes: d787dcdb9c8f ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus") Cc: stable <stable@vger.kernel.org> # 4.4.x 7a3b7cd332db of: device: Export of_device_{get_modalias, uvent_modalias} to modules Acked-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2017-08-16bus: Convert to using %pOF instead of full_nameRob Herring
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> Cc: Chen-Yu Tsai <wens@csie.org> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2016-01-25drivers: sunxi-rsb: fix error output typeAndre Przywara
"len" is actually a size_t in this function here, so properly annotate the dev_err printf type to allow compilation for 64-bit architectures. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2015-12-22bus: sunxi-rsb: Fix peripheral IC mapping runtime addressChen-Yu Tsai
0x4e is the runtime address normally associated with perihperal ICs. 0x45 is not a valid runtime address. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Olof Johansson <olof@lixom.net>
2015-12-22bus: sunxi-rsb: Fix primary PMIC mapping hardware addressChen-Yu Tsai
The primary PMICs use 0x3a3 as their hardware address, not 0x3e3. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Olof Johansson <olof@lixom.net>
2015-11-17bus: sunxi-rsb: unlock on error in sunxi_rsb_read()Dan Carpenter
Don't forget to unlock before returning an error code. Fixes: d787dcdb9c8f ('bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2015-10-26bus: sunxi-rsb: Add driver for Allwinner Reduced Serial BusChen-Yu Tsai
Reduced Serial Bus (RSB) is an Allwinner proprietery interface used to communicate with PMICs and other peripheral ICs. RSB is a two-wire push-pull serial bus that supports 1 master device and up to 15 active slave devices. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Olof Johansson <olof@lixom.net>