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2018-08-10gpiolib: Avoid calling chip->request() for unused gpiosBiju Das1-1/+6
Add a check for unused gpios to avoid chip->request() call to client driver for unused gpios. Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpio: tegra: Include the right headerLinus Walleij1-2/+2
This is a GPIO driver so include only <linux/gpio/driver.h>. Drop the use of GPIOF_* flags: these are for consumers, not drivers. Just return 0/1. Cc: Stefan Agner <stefan@agner.ch> Cc: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpio: mmio: Fix up inverted direction registersLinus Walleij2-45/+66
The bgpio_init() takes one of two arguments to specify a register to set the direction of the GPIO line: either dirout that indicates that a 1 in the bit in that register sets the corresponding line to output, or dirin which indicates that a 1 in the bit in that register sets the corresponding line to input. Conversely setting the bit to 0 on these will turn the line into input and output respectively. One of these can be defined but not both. This means that a platform that sets a bit to 1 for output only defines dirout and a platform that sets a bit to 0 for output only defines dirin. In short this defines the polarity of the direction register. Both can also be left as NULL meaning the GPIO chip is either input only or output only. Tomer Maimon discovered that for get/set chips (those where the get and set registers are defined but no separate clear register, and specifying BGPIOF_READ_OUTPUT_REG_SET so that we say we want to read the output value from the SET register) we are unconditionally reading the value from the SET register when the direction bit is 1 and from the DAT register when the direction bit is 0, not taking the direction bit polarity into account. It would be expected that when the direction bit is inverted (dirin is defined but not dirout) we read the current value from the DAT register when the bit is 1 and from the SET register when the bit is 0. Currently only some versions of ATH79, brcmstb, some versions of CLP711x, GE, IOP and Loongson use the dirin mode (a 1 in the register means input). They are unaffected because BGPIOF_READ_OUTPUT_REG_SET is not set on any of them. (They do not read back the SET register to figure out the output value.) So this is no regression with current drivers. However the behaviour is wrong and does not work with Tomer's new driver where he needs to use the BGIOF_READ_OUTPUT_REG_SET. This fixes the above issue by: - Instead of defining separate functions for the inverted case, set up a flag in the gpio_chip that indicates that the direction is inverted. - Remove the special inverted functions for setting input/output and getting the direction, rely on the flag instead. - Respect this flag in bgpio_get_set() and bgpio_get_set_multiple() Reported-by: Tomer Maimon <tmaimon77@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpio: xilinx: Use the right includeLinus Walleij1-1/+1
This is a GPIO driver so use only <linux/gpio/driver.h>. Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpio: timberdale: Include the right headerLinus Walleij1-1/+1
This is a GPIO driver so include only <linux/gpio/driver.h>. Cc: Richard Röjfors <richard.rojfors@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpio: tb10x: Use the right includeLinus Walleij1-2/+1
This driver includes the legacy <linux/gpio.h> and <linux/of_gpio.h> but all it needs is really <linux/gpio/driver.h>. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpiolib: Fix of_node inconsistencyBiju Das2-3/+2
Some platforms are not setting of_node in the driver. On these platforms defining gpio-reserved-ranges on device tree leads to kernel crash. It is due to some parts of the gpio core relying on the driver to set up of_node,while other parts do themselves.This inconsistent behaviour leads to a crash. gpiochip_add_data_with_key() calls gpiochip_init_valid_mask() with of_node as NULL. of_gpiochip_add() fills "of_node" and calls of_gpiochip_init_valid_mask(). The fix is to move the assignment to chip->of_node from of_gpiochip_add() to gpiochip_add_data_with_key(). Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: vr41xx: Bail out on gpiochip_lock_as_irq() errorAndy Shevchenko1-1/+7
gpiochip_lock_as_irq() may return a few error codes, bail out if it fails with corresponding returned code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: uniphier: Bail out on gpiochip_lock_as_irq() errorAndy Shevchenko1-2/+1
gpiochip_lock_as_irq() may return a few error codes, bail out if it fails with corresponding returned code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: xgene-sb: Don't shadow error code of gpiochip_lock_as_irq()Andy Shevchenko1-2/+4
gpiochip_lock_as_irq() may return a few error codes, do not shadow them by -ENOSPC and let caller to decide. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: em: Don't shadow error code of gpiochip_lock_as_irq()Andy Shevchenko1-2/+4
gpiochip_lock_as_irq() may return a few error codes, do not shadow them by -EINVAL and let caller to decide. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: dwapb: Don't shadow error code of gpiochip_lock_as_irq()Andy Shevchenko1-2/+4
gpiochip_lock_as_irq() may return a few error codes, do not shadow them by -EINVAL and let caller to decide. No functional change intended. Cc: Hoan Tran <hotran@apm.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: bcm-kona: Don't shadow error code of gpiochip_lock_as_irq()Andy Shevchenko1-2/+4
gpiochip_lock_as_irq() may return a few error codes, do not shadow them by -EINVAL and let caller to decide. No functional change intended. Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpiolib: Don't shadow error code of gpiochip_lock_as_irq()Andy Shevchenko1-2/+4
gpiochip_lock_as_irq() may return a few error codes, do not shadow them by -EINVAL and let caller to decide. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: syscon: rockchip: add GRF GPIO support for rk3328Levin Du2-0/+63
In Rockchip RK3328, the output only GPIO_MUTE pin, originally for codec mute control, can also be used for general purpose. It is manipulated by the GRF_SOC_CON10 register in GRF. Aside from the GPIO_MUTE pin, the HDMI pins can also be set in the same way. Currently this GRF GPIO controller only supports the mute pin. If needed in the future, the HDMI pins support can also be added. Signed-off-by: Levin Du <djw@t-chip.com.cn> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpio: omap: Add get/set_multiple() callbacksJanusz Krzysztofik1-2/+86
This should make applications utilizing whole banks work faster. Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Acked-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-02gpio: pxa: remove set but not used variable 'gpio_offset'Wei Yongjun1-4/+1
Fixes gcc '-Wunused-but-set-variable' warning: drivers/gpio/gpio-pxa.c: In function "pxa_gpio_probe": drivers/gpio/gpio-pxa.c:629:35: warning: variable "gpio_offset" set but not used [-Wunused-but-set-variable] int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0; ^ Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-30gpio-it87: add support for IT8786E Super I/OVincent Prince1-0/+2
From the datasheet, the GPIO interface is identical to IT8728 (same description), so just add it to the same case as the other chip. Signed-off-by: Vincent Prince <vincent.prince.fr@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-30gpiolib: Use GPIOD_OUT_{LOW,HIGH} macros in open drain onesAndy Shevchenko1-5/+2
There should not be anything more than stated by the name of newly introduced constants, i.e. GPIOD_OUT_LOW_OPEN_DRAIN == GPIOD_OUT_LOW + open drain and nothing more. Make it better to read and slightly more robust by using GPIOD_OUT_LOW and GPIOD_OUT_HIGH constants with open drain flag. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: tegra: drop tegra specific GPIO lockdep classesStefan Agner1-9/+0
Since commit e45d1c80c0ee ("gpio: put GPIO IRQs into their own lock class") and commit a0a8bcf4670c ("gpiolib: irqchip: use different lockdep class for each gpio irqchip") GPIO lib takes care of lockdep classes. In fact, gpiochip_irq_map() overwrites the class anyway, so the lockdep class set by the driver is useless. Remove it. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: fix meaningless return expressionzhong jiang1-1/+1
Fix the following sparse error: drivers/gpio/gpio-ath79.c:54:16: error: return expression in void function Signed-off-by: zhong jiang <zhongjiang@huawei.com> Acked-by: Alban Bedel <albeu@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: mxs: Fit writel() into a single lineFabio Estevam1-2/+1
There is no need for splitting the writel() call in two lines. Make it fit into a single line instead. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: pxa: disable pinctrl calls for PXA3xxDaniel Mack1-8/+27
The pxa3xx driver uses the pinctrl-single driver since a while which does not implement a .gpio_set_direction() callback. The pinmux core will simply return 0 in this case, and the pxa3xx gpio driver hence believes the pinctrl driver did its job and returns as well. This effectively makes pxa_gpio_direction_{input,output} no-ops. To fix this, do not call into the pinctrl subsystem for the PXA3xx platform for now. We can revert this once the pinctrl-single driver learned to support setting pin directions. Signed-off-by: Daniel Mack <daniel@zonque.org> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: ml-ioh: Fix buffer underwrite on probe error pathAnton Vasilyev1-1/+2
If ioh_gpio_probe() fails on devm_irq_alloc_descs() then chip may point to any element of chip_save array, so reverse iteration from pointer chip may become chip_save[-1] and gpiochip_remove() will operate with wrong memory. The patch fix the error path of ioh_gpio_probe() to correctly bypass chip_save array. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpiolib: probe deferral error reportingMarcel Ziswiler1-2/+2
Actually report the error code from devm_regulator_get() which may as well just be a probe deferral. This is e.g. what one gets upon booting a Colibri T20: gpiochip_add_data_with_key: GPIOs 0..223 (tegra-gpio) failed to register Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: tegra: Fix tegra_gpio_irq_set_type()Dmitry Osipenko1-7/+8
Commit 36b312792b97 ("gpiolib: Respect error code of ->get_direction()") broke tegra_gpio_irq_set_type() because requesting of GPIO direction must be done after enabling GPIO function for a pin. This patch fixes drivers probe failure like this: gpio gpiochip0: (tegra-gpio): gpiochip_lock_as_irq: cannot get GPIO direction tegra-gpio 6000d000.gpio: unable to lock Tegra GPIO 144 as IRQ Fixes: 36b312792b97 ("gpiolib: Respect error code of ->get_direction()") Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio: mxc: add power management supportAnson Huang1-0/+73
GPIO registers could lose context on i.MX7D, when enter LPSR mode, the whole SoC will be powered off except LPSR domain, GPIO banks will lose context in this case, need to restore the context after resume from LPSR mode. This patch adds new compatible string for i.MX7D which supports GPIO power off feature in suspend, and adds the GPIO save/restore operations in noirq suspend/resume phase, since GPIO is fundamental module which could be used by other peripherals' resume phase. Signed-off-by: Anson Huang <Anson.Huang@nxp.com> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpio-pisosr: add support for get_multipleMorten Hein Tiljeset1-0/+22
Signed-off-by: Morten Hein Tiljeset <morten.tiljeset@prevas.dk> Reviewed-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-16gpiolib: remove an unnecessary TODOBartosz Golaszewski1-1/+1
It's actually fine to read values of output lines. This was also allowed by the legacy sysfs interface. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-16gpiolib: don't allow userspace to set values of input linesBartosz Golaszewski1-1/+7
User space can currently both read and set values of input lines using the character device. This was not allowed by the old sysfs interface nor is it a correct behavior. Check the first descriptor in the set for the OUT flag when asked to set values and return -EPERM if the line is input. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpio: rcar: Implement .get_direction() callbackGeert Uytterhoeven1-0/+8
Allow gpiolib to read back the current I/O direction configuration by implementing the .get_direction() callback. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpiolib: Join one line back for better readabilityAndy Shevchenko1-3/+1
One line in gpiolib_dbg_show() still fits 80 characters, so, join it to be like that in order to increase readability. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpio: pxa: Fix potential NULL dereferenceWei Yongjun1-0/+2
platform_get_resource() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference a bit later in the code. This is detected by Coccinelle semantic patch. @@ expression pdev, res, n, t, e, e1, e2; @@ res = platform_get_resource(pdev, t, n); + if (!res) + return -EINVAL; ... when != res == NULL e = devm_ioremap(e1, res->start, e2); Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpio: mt7621: add OF_GPIO dependencyArnd Bergmann1-0/+1
Compile-testing the driver fails unless OF_GPIO is enabled: drivers/gpio/gpio-mt7621.c: In function 'mediatek_gpio_bank_probe': drivers/gpio/gpio-mt7621.c:228:10: error: 'struct gpio_chip' has no member named 'of_node' Fixes: 4ba9c3afda41 ("gpio: mt7621: Add a driver for MT7621") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpio: aspeed: fix compile testing warningArnd Bergmann1-1/+1
Gcc cannot always see that BUG_ON(1) is guaranteed to not return, so we get a warning message in some configurations: drivers/gpio/gpio-aspeed.c: In function 'bank_reg': drivers/gpio/gpio-aspeed.c:244:1: error: control reaches end of non-void function [-Werror=return-type] Using a plain BUG() is easier here and avoids the problem. Fixes: 44ddf559d579 ("gpio: aspeed: Rework register type accessors") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpiolib: Consistent use of ->get_direction() inside gpiolibAndy Shevchenko1-6/+1
Two out of three calls to ->get_direction (excluding, of course, gpiod_get_direction() itself) are using gpiod_get_direction() and one is still open coded. Replace the latter one to use same API for sake of consistency. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpiolib: Mark gpio_suffixes array with __maybe_unusedAndy Shevchenko1-1/+1
Since we put static variable to a header file it's copied to each module that includes the header. But not all of them are actually used it. Mark gpio_suffixes array with __maybe_unused to hide a compiler warning: In file included from drivers/gpio/gpiolib-legacy.c:6:0: drivers/gpio/gpiolib.h:95:27: warning: ‘gpio_suffixes’ defined but not used [-Wunused-const-variable=] static const char * const gpio_suffixes[] = { "gpios", "gpio" }; ^~~~~~~~~~~~~ In file included from drivers/gpio/gpiolib-devprop.c:17:0: drivers/gpio/gpiolib.h:95:27: warning: ‘gpio_suffixes’ defined but not used [-Wunused-const-variable=] static const char * const gpio_suffixes[] = { "gpios", "gpio" }; ^~~~~~~~~~~~~ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpio: selftests: gpio-mockup-chardev GPIOHANDLE_REQUEST_OUTPUT fixRafael David Tinoco1-3/+3
Following logic from commit: 22f6592b23, GPIOHANDLE_REQUEST_OUTPUT should handle errors same way as GPIOHANDLE_REQUEST_INPUT does, or else the following error occurs: gpio-mockup-chardev: gpio<gpiochip1> line<0> test flag<0x2> value<0>: No such file or directory despite the real result of gpio_pin_test(), gpio_debugfs_get() and gpiotools_request_linehandle() functions. Signed-off-by: Rafael David Tinoco <rafael.tinoco@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpiolib: Defer on non-DT find_chip_by_name() failureJanusz Krzysztofik1-3/+10
Avoid replication of error code conversion in non-DT GPIO consumers' code by returning -EPROBE_DEFER from gpiod_find() in case a chip identified by its label in a registered lookup table is not ready. See https://lkml.org/lkml/2018/5/30/176 for example case. Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpiolib: Respect error code of ->get_direction()Andy Shevchenko1-0/+6
In case we try to lock GPIO pin as IRQ when something going wrong we print a misleading message. Correct this by checking an error code from ->get_direction() in gpiochip_lock_as_irq() and printing a corresponding message. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpio: mxc: Add clocks optional binding for imx gpioAnson Huang1-0/+3
Some i.MX SoCs have GPIO clock gate in CCM, accessing GPIO registers needs to enable GPIO clock gate first, i.MX GPIO driver will enable clock gate if there is clock property in GPIO node of dtb, add optional property to i.MX GPIO binding doc. Signed-off-by: Anson Huang <Anson.Huang@nxp.com> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpio: mt7621: Edit to preferred syntaxLinus Walleij1-44/+41
This fixes some syntactic nits that makes the GPIO maintainer happier. It is way easier to show by example and do it myself than to try to explain it with comments. It's just my personal taste of minimalism. Cc: Sergio Paracuellos <sergio.paracuellos@gmail.com> Cc: NeilBrown <neil@brown.name> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpio: mt7621: Add a driver for MT7621Sergio Paracuellos3-0/+344
Add driver support for gpio of MT7621 SoC. Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com> Reviewed-by: NeilBrown <neil@brown.name> [Switched wording WIDTH to STRIDE] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpio: mt7621: Add DT bindingsSergio Paracuellos1-0/+35
Add a devicetree binding documentation for the mt7621 gpio. Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com> Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-09gpiolib: Join string literals backAndy Shevchenko1-7/+5
For easy grepping on debug purposes join string literals back in the messages. While here, fix couple of small indentation issues. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-02Merge branch 'ib-aspeed' into develLinus Walleij2-58/+383
2018-07-02gpio: aspeed: Add interfaces for co-processor to grab GPIOsBenjamin Herrenschmidt2-20/+246
On the Aspeed chip, the GPIOs can be under control of the ARM chip or of the ColdFire coprocessor. (There's a third command source, the LPC bus, which we don't use or support yet). The control of which master is allowed to modify a given GPIO is per-bank (8 GPIOs). Unfortunately, systems already exist for which we want to use GPIOs of both sources in the same bank. This provides an API exported by the gpio-aspeed driver that an aspeed coprocessor driver can use to "grab" some GPIOs for use by the coprocessor, and allow the coprocessor driver to provide callbacks for arbitrating access. Once at least one GPIO of a given bank has been "grabbed" by the coprocessor, the entire bank is marked as being under coprocessor control. It's command source is switched to the coprocessor. If the ARM then tries to write to a GPIO in such a marked bank, the provided callbacks are used to request access from the coprocessor driver, which is responsible to doing whatever is necessary to "pause" the coprocessor or prevent it from trying to use the GPIOs while the ARM is doing its accesses. During that time, the command source for the bank is temporarily switched back to the ARM. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-02gpio: aspeed: Add command source registersBenjamin Herrenschmidt1-0/+54
This adds the definitions for the command source registers and a helper to set them. Those registers allow to control which bus master on the SoC is allowed to modify a given bank of GPIOs and will be used by subsequent patches. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-02gpio: aspeed: Add "Read Data" register to read the write latchBenjamin Herrenschmidt1-2/+27
The Aspeed GPIO hardware has a quirk: the value register, for an output GPIO, doesn't contain the last value written (the write latch content) but the sampled input value. This means that when reading back shortly after writing, you can get an incorrect value as the input value is delayed by a few synchronizers. The HW supports a separate read-only register "Data Read Register" which allows you to read the write latch instead. This adds the definition for it, and uses it for the initial population of the GPIO value cache. It will be used more in subsequent patches. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-02gpio: aspeed: Rework register type accessorsBenjamin Herrenschmidt1-49/+69
Use a single accessor function for all register types instead of several spread around. This will make it easier/cleaner to introduce new registers and keep the mechanism in one place. The big switch/case is optimized at compile time since the switch value is a constant. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>