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* gpio: fix error path in lineevent_createUwe Kleine-König2018-05-161-1/+1
| | | | | | | | | | | | | commit f001cc351ad3309ec8736c374e90e5a4bc472d41 upstream. If gpiod_request() fails the cleanup must not call gpiod_free(). Cc: stable@vger.kernel.org Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: fix aspeed_gpio unmask irqGovert Overgaauw2018-05-161-1/+1
| | | | | | | | | | | | | commit f241632fd087d3d9fbd5450f4d8c8604badd8348 upstream. The unmask function disables all interrupts in a bank when unmasking an interrupt. Only disable the given interrupt. Cc: stable@vger.kernel.org Signed-off-by: Govert Overgaauw <govert.overgaauw@prodrive-technologies.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpioib: do not free unrequested descriptorsTimur Tabi2018-05-161-2/+3
| | | | | | | | | | | | | | | | | | | | | | commit ab3dbcf78f60f46d6a0ad63b1f4b690b7a427140 upstream. If the main loop in linehandle_create() encounters an error, it unwinds completely by freeing all previously requested GPIO descriptors. However, if the error occurs in the beginning of the loop before that GPIO is requested, then the exit code attempts to free a null descriptor. If extrachecks is enabled, gpiod_free() triggers a WARN_ON. Instead, keep a separate count of legitimate GPIOs so that only those are freed. Cc: stable@vger.kernel.org Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Timur Tabi <timur@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: label descriptors using the device nameLinus Walleij2018-04-131-1/+2
| | | | | | | | | | | | | | | | | | | | | [ Upstream commit 24e78079bf2250874e33da2e7cfbb6db72d3caf4 ] Some GPIO lines appear named "?" in the lsgpio dump due to their requesting drivers not passing a reasonable label. Most typically this happens if a device tree node just defines gpios = <...> and not foo-gpios = <...>, the former gets named "foo" and the latter gets named "?". However the struct device passed in is always valid so let's just label the GPIO with dev_name() on the device if no proper label was passed. Cc: Reported-by: Jason Kridner <jkridner@beagleboard.org> Reported-by: Jason Kridner <jkridner@beagleboard.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: crystalcove: Do not write regular gpio registers for virtual GPIOsHans de Goede2018-04-131-18/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 9a752b4c9ab924033bfdb8784c680d50b2bd5684 ] The Crystal Cove PMIC has 16 real GPIOs but the ACPI code for devices with this PMIC may address up to 95 GPIOs, these extra GPIOs are called virtual GPIOs and are used by the ACPI code as a method of accessing various non GPIO bits of PMIC. Commit dcdc3018d635 ("gpio: crystalcove: support virtual GPIO") added dummy support for these to avoid a bunch of ACPI errors, but instead of ignoring writes / reads to them by doing: if (gpio >= CRYSTALCOVE_GPIO_NUM) return 0; It accidentally introduced the following wrong check: if (gpio > CRYSTALCOVE_VGPIO_NUM) return 0; Which means that attempts by the ACPI code to access these gpios causes some arbitrary gpio to get touched through for example GPIO1P0CTLO + gpionr % 8. Since we do support input/output (but not interrupts) on the 0x5e virtual GPIO, this commit makes to_reg return -ENOTSUPP for unsupported virtual GPIOs so as to not have to check for (gpio >= CRYSTALCOVE_GPIO_NUM && gpio != 0x5e) everywhere and to make it easier to add support for more virtual GPIOs in the future. It then adds a check for to_reg returning an error to all callers where this may happen fixing the ACPI code accessing virtual GPIOs accidentally causing changes to real GPIOs. Fixes: dcdc3018d635 ("gpio: crystalcove: support virtual GPIO") Cc: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: gpio-wcove: fix GPIO IRQ status maskKuppuswamy Sathyanarayanan2018-03-241-2/+4
| | | | | | | | | | | | | | | | [ Upstream commit 881ebd229f4a5ea88f269c1225245e50db9ba303 ] According to Whiskey Cove PMIC spec, bit 7 of GPIOIRQ0_REG belongs to battery IO. So we should skip this bit when checking for GPIO IRQ pending status. Otherwise, wcove_gpio_irq_handler() might go into the infinite loop until IRQ "pending" status becomes 0. This patch fixes this issue. Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: gpio-wcove: fix irq pending status bit widthKuppuswamy Sathyanarayanan2018-03-241-1/+1
| | | | | | | | | | | | | | | [ Upstream commit 7c2d176fe3f8dce632b948f79c7e89916ffe2c70 ] Whiskey cove PMIC has three GPIO banks with total number of 13 GPIO pins. But when checking for the pending status, for_each_set_bit() uses bit width of 7 and hence it only checks the status for first 7 GPIO pins missing to check/clear the status of rest of the GPIO pins. This patch fixes this issue. Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: xgene: mark PM functions as __maybe_unusedArnd Bergmann2018-02-251-10/+3
| | | | | | | | | | | | | | | | | | | | commit b115bebc07f282067eccc06fd5aa3060ab1426da upstream. When CONFIG_PM_SLEEP is disabled, we get a warning about unused functions: drivers/gpio/gpio-xgene.c:155:12: warning: 'xgene_gpio_resume' defined but not used [-Wunused-function] static int xgene_gpio_resume(struct device *dev) ^~~~~~~~~~~~~~~~~ drivers/gpio/gpio-xgene.c:142:12: warning: 'xgene_gpio_suspend' defined but not used [-Wunused-function] static int xgene_gpio_suspend(struct device *dev) The warnings are harmless and can be avoided by simplifying the code and marking the functions as __maybe_unused. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: intel-mid: Fix build warning when !CONFIG_PMAugusto Mecking Caringi2018-02-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | commit fbc2a294f29e726787a0f5238b27137904f26b81 upstream. The only usage of function intel_gpio_runtime_idle() is here (in the same file): static const struct dev_pm_ops intel_gpio_pm_ops = { SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle) }; And when CONFIG_PM is not set, the macro SET_RUNTIME_PM_OPS expands to nothing, causing the following compiler warning: drivers/gpio/gpio-intel-mid.c:324:12: warning: ‘intel_gpio_runtime_idle’ defined but not used [-Wunused-function] static int intel_gpio_runtime_idle(struct device *dev) Fix it by annotating the function with __maybe_unused. Signed-off-by: Augusto Mecking Caringi <augustocaringi@gmail.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: ath79: add missing MODULE_DESCRIPTION/LICENSEJesse Chan2018-02-031-0/+3
| | | | | | | | | | | | | | | | | | | | commit 539340f37e6d6ed4cd93e8e18c9b2e4eafd4b842 upstream. This change resolves a new compile-time warning when built as a loadable module: WARNING: modpost: missing MODULE_LICENSE() in drivers/gpio/gpio-ath79.o see include/linux/module.h for more information This adds the license as "GPL v2", which matches the header of the file. MODULE_DESCRIPTION is also added. Signed-off-by: Jesse Chan <jc@linux.com> Acked-by: Alban Bedel <albeu@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: iop: add missing MODULE_DESCRIPTION/AUTHOR/LICENSEJesse Chan2018-02-031-0/+4
| | | | | | | | | | | | | | | | | | | commit 97b03136e1b637d7a9d2274c099e44ecf23f1103 upstream. This change resolves a new compile-time warning when built as a loadable module: WARNING: modpost: missing MODULE_LICENSE() in drivers/gpio/gpio-iop.o see include/linux/module.h for more information This adds the license as "GPL", which matches the header of the file. MODULE_DESCRIPTION and MODULE_AUTHOR are also added. Signed-off-by: Jesse Chan <jc@linux.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: Fix kernel stack leak to userspaceLinus Walleij2018-02-031-0/+3
| | | | | | | | | | | | | | | commit 24bd3efc9d1efb5f756a7c6f807a36ddb6adc671 upstream. The GPIO event descriptor was leaking kernel stack to userspace because we don't zero the variable before use. Ooops. Fix this. Reported-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: stmpe: i2c transfer are forbiden in atomic contextPatrice Chotard2018-02-031-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b888fb6f2a278442933e3bfab70262e9a5365fb3 upstream. Move the workaround from stmpe_gpio_irq_unmask() which is executed in atomic context to stmpe_gpio_irq_sync_unlock() which is not. It fixes the following issue: [ 1.500000] BUG: scheduling while atomic: swapper/1/0x00000002 [ 1.500000] CPU: 0 PID: 1 Comm: swapper Not tainted 4.15.0-rc2-00020-gbd4301f-dirty #28 [ 1.520000] Hardware name: STM32 (Device Tree Support) [ 1.520000] [<0000bfc9>] (unwind_backtrace) from [<0000b347>] (show_stack+0xb/0xc) [ 1.530000] [<0000b347>] (show_stack) from [<0001fc49>] (__schedule_bug+0x39/0x58) [ 1.530000] [<0001fc49>] (__schedule_bug) from [<00168211>] (__schedule+0x23/0x2b2) [ 1.550000] [<00168211>] (__schedule) from [<001684f7>] (schedule+0x57/0x64) [ 1.550000] [<001684f7>] (schedule) from [<0016a513>] (schedule_timeout+0x137/0x164) [ 1.550000] [<0016a513>] (schedule_timeout) from [<00168b91>] (wait_for_common+0x8d/0xfc) [ 1.570000] [<00168b91>] (wait_for_common) from [<00139753>] (stm32f4_i2c_xfer+0xe9/0xfe) [ 1.580000] [<00139753>] (stm32f4_i2c_xfer) from [<00138545>] (__i2c_transfer+0x111/0x148) [ 1.590000] [<00138545>] (__i2c_transfer) from [<001385cf>] (i2c_transfer+0x53/0x70) [ 1.590000] [<001385cf>] (i2c_transfer) from [<001388a5>] (i2c_smbus_xfer+0x12f/0x36e) [ 1.600000] [<001388a5>] (i2c_smbus_xfer) from [<00138b49>] (i2c_smbus_read_byte_data+0x1f/0x2a) [ 1.610000] [<00138b49>] (i2c_smbus_read_byte_data) from [<00124fdd>] (__stmpe_reg_read+0xd/0x24) [ 1.620000] [<00124fdd>] (__stmpe_reg_read) from [<001252b3>] (stmpe_reg_read+0x19/0x24) [ 1.630000] [<001252b3>] (stmpe_reg_read) from [<0002c4d1>] (unmask_irq+0x17/0x22) [ 1.640000] [<0002c4d1>] (unmask_irq) from [<0002c57f>] (irq_startup+0x6f/0x78) [ 1.650000] [<0002c57f>] (irq_startup) from [<0002b7a1>] (__setup_irq+0x319/0x47c) [ 1.650000] [<0002b7a1>] (__setup_irq) from [<0002bad3>] (request_threaded_irq+0x6b/0xe8) [ 1.660000] [<0002bad3>] (request_threaded_irq) from [<0002d0b9>] (devm_request_threaded_irq+0x3b/0x6a) [ 1.670000] [<0002d0b9>] (devm_request_threaded_irq) from [<001446e7>] (mmc_gpiod_request_cd_irq+0x49/0x8a) [ 1.680000] [<001446e7>] (mmc_gpiod_request_cd_irq) from [<0013d45d>] (mmc_start_host+0x49/0x60) [ 1.690000] [<0013d45d>] (mmc_start_host) from [<0013e40b>] (mmc_add_host+0x3b/0x54) [ 1.700000] [<0013e40b>] (mmc_add_host) from [<00148119>] (mmci_probe+0x4d1/0x60c) [ 1.710000] [<00148119>] (mmci_probe) from [<000f903b>] (amba_probe+0x7b/0xbe) [ 1.720000] [<000f903b>] (amba_probe) from [<001170e5>] (driver_probe_device+0x169/0x1f8) [ 1.730000] [<001170e5>] (driver_probe_device) from [<001171b7>] (__driver_attach+0x43/0x5c) [ 1.740000] [<001171b7>] (__driver_attach) from [<0011618d>] (bus_for_each_dev+0x3d/0x46) [ 1.740000] [<0011618d>] (bus_for_each_dev) from [<001165cd>] (bus_add_driver+0xcd/0x124) [ 1.740000] [<001165cd>] (bus_add_driver) from [<00117713>] (driver_register+0x4d/0x7a) [ 1.760000] [<00117713>] (driver_register) from [<001fc765>] (do_one_initcall+0xbd/0xe8) [ 1.770000] [<001fc765>] (do_one_initcall) from [<001fc88b>] (kernel_init_freeable+0xfb/0x134) [ 1.780000] [<001fc88b>] (kernel_init_freeable) from [<00167ee3>] (kernel_init+0x7/0x9c) [ 1.790000] [<00167ee3>] (kernel_init) from [<00009b65>] (ret_from_fork+0x11/0x2c) Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: altera: Use handle_level_irq when configured as a level_highPhil Reid2017-12-141-15/+11
| | | | | | | | | | | | | | | | | | | | [ Upstream commit f759921cfbf4847319d197a6ed7c9534d593f8bc ] When a threaded irq handler is chained attached to one of the gpio pins when configure for level irq the altera_gpio_irq_leveL_high_handler does not mask the interrupt while being handled by the chained irq. This resulting in the threaded irq not getting enough cycles to complete quickly enough before the irq was disabled as faulty. handle_level_irq should be used in this situation instead of handle_simple_irq. In gpiochip_irqchip_add set default handler to handle_bad_irq as per Documentation/gpio/driver.txt. Then set the correct handler in the set_type callback. Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: mockup: dynamically allocate memory for chip nameBartosz Golaszewski2017-11-301-3/+7
| | | | | | | | | | | | | | | [ Upstream commit ad6d8004fa29a8958381b60215e32d1e903b0492 ] Currently the chip name buffer is allocated on the stack and the address of the buffer is passed to the gpio framework. It's invalid after probe() returns, so the sysfs label attribute displays garbage. Use devm_kasprintf() for each string instead. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: mcp23s08: Select REGMAP/REGMAP_I2C to fix build errorAxel Lin2017-11-081-0/+2
| | | | | | | | | | | | | | [ Upstream commit e8e1a5b5679b1ae1ff03a3883b011b84e7226171 ] This driver now using devm_regmap_init/devm_regmap_init_i2c, so it needs to select REGMAP/REGMAP_I2C accordingly. Fixes: ("3d84fdb3f0b5 gpio: mcp23s08: use regmap") Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-By: Sebastian Reichel <sre@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpiolib: skip unwanted events, don't convert them to opposite edgeBartosz Golaszewski2017-08-111-5/+4
| | | | | | | | | | | | | | | | | commit df1e76f28ffe87d1b065eecab2d0fbb89e6bdee5 upstream. The previous fix for filtering out of unwatched events was not entirely correct. Instead of skipping the events we don't want, they are now interpreted as events with opposing edge. In order to fix it: always read the GPIO line value on interrupt and only emit the event if it corresponds with the event type we requested. Fixes: ad537b822577 ("gpiolib: fix filtering out unwanted events") Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpiolib: fix filtering out unwanted eventsBartosz Golaszewski2017-07-051-1/+2
| | | | | | | | | | | | | | | | | | commit ad537b822577fcc143325786cd6ad50d7b9df31c upstream. GPIOEVENT_REQUEST_BOTH_EDGES is not a single flag, but a binary OR of GPIOEVENT_REQUEST_RISING_EDGE and GPIOEVENT_REQUEST_FALLING_EDGE. The expression 'le->eflags & GPIOEVENT_REQUEST_BOTH_EDGES' we'll get evaluated to true even if only one event type was requested. Fix it by checking both RISING & FALLING flags explicitly. Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: omap: return error if requested debounce time is not possibleDavid Rivshin2017-05-251-6/+17
| | | | | | | | | | | | | | | | | | | | | | | commit 83977443938122baeed28dc9f078db3da9855f7c upstream. omap_gpio_debounce() does not validate that the requested debounce is within a range it can handle. Instead it lets the register value wrap silently, and always returns success. This can lead to all sorts of unexpected behavior, such as gpio_keys asking for a too-long debounce, but getting a very short debounce in practice. Fix this by returning -EINVAL if the requested value does not fit into the register field. If there is no debounce clock available at all, return -ENOTSUPP. Fixes: e85ec6c3047b ("gpio: omap: fix omap2_set_gpio_debounce") Signed-off-by: David Rivshin <drivshin@allworx.com> Acked-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ACPI / gpio: do not fall back to parsing _CRS when we get a deferralDmitry Torokhov2017-04-121-1/+3
| | | | | | | | | | | | | | | commit 693bdaa164b40b7aa6018b98af6f7e40dbd52457 upstream. If, while locating GPIOs by name, we get probe deferral, we should immediately report it to caller rather than trying to fall back to parsing unnamed GPIOs from _CRS block. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-and-Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: Move freeing of GPIO hogs before numbing of the deviceGeert Uytterhoeven2017-01-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | commit 5018ada69a04c8ac21d74bd682fceb8e42dc0f96 upstream. When removing a gpiochip that uses GPIO hogging (e.g. by unloading the chip's DT overlay), a warning is printed: gpio gpiochip8: REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED This happens because gpiochip_free_hogs() is called after the gdev->chip pointer is reset to NULL. Hence __gpiod_free() cannot determine the chip in use, and cannot clear flags nor call the optional chip-specific .free() callback. Move the call to gpiochip_free_hogs() up to fix this. Fixes: ff2b135922992756 ("gpio: make the gpiochip a real device") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: chardev: Return error for seek operationsLars-Peter Clausen2017-01-091-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f4e81c529767b9a33d1b27695c54dc84a14af30d upstream. The GPIO chardev is used for management tasks (allocating line and event handles) and does neither support read() nor write() operations. Hence it does not make much sense to allow seek operations. Currently the chardev uses noop_llseek() for its seek implementation. This function does not move the pointer and simply returns the current position (always 0 for the GPIO chardev). noop_llseek() is primarily meant for devices that can not support seek, but where there might be a user that depends on the seek() operation succeeding. For newly added devices that can not support seek operations it is recommended to use no_llseek(), which will return an error. For more information see commit 6038f373a3dc ("llseek: automatically add .llseek fop"). Unfortunately this was overlooked when the GPIO chardev ABI was introduced. But it is highly unlikely that since then userspace applications have appeared that rely on being able to perform non-failing seek operations on a GPIO chardev file descriptor. So it should be safe to change from noop_llseel() to no_seek(). Also use nonseekable_open() in the chardev open() callback to clear the FMODE_SEEK, FMODE_PREAD and FMODE_PWRITE flags from the file. Neither of these should be set on a file that does not support seek operations. Fixes: 3c702e9987e2 ("gpio: add a userspace chardev ABI for GPIOs") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: stmpe: fix interrupt handling bugLinus Walleij2017-01-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1516c6350aa2770b8a5e36d40c3ec5078f92ba70 upstream. commit 43db289d00c6 ("gpio: stmpe: Rework registers access") reworked the STMPE register access so as to use [STMPE_IDX_*_LSB + i] to access the 8bit register for a certain bank, assuming the CSB and MSB will follow after the enumerator. For this to work the index needs to go from (size-1) to 0 not 0 to (size-1). However for the GPIO IRQ handler, the status registers we read register MSB + 3 bytes ahead for the 24 bit GPIOs and index registers from MSB upwards and run an index i over the registers UNLESS we are STMPE1600. This is not working when we get to clearing the interrupt EDGE status register STMPE_IDX_GPEDR_[LCM]SB: it is indexed like all other registers [STMPE_IDX_*_LSB + i] but in this loop we index from 0 to get the right bank index for the calculations, and we need to just add i to the MSB. Before this, interrupts on the STMPE2401 were broken, this patch fixes it so it works again. Cc: Patrice Chotard <patrice.chotard@st.com> Fixes: 43db289d00c6 ("gpio: stmpe: Rework registers access") Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* gpio: Remove GPIO_DEVRES optionKeno Fischer2016-11-162-5/+1
| | | | | | | | | | | | | | | | | | | | | This option was added in 6a89a314ab107a12af08c71420c19a37a30fc2d3 to allow use of the devm_gpio_* functions without CONFIG_GPIOLIB. However, only a few months later in b69ac52449c658b7ac40034dc3c5f5f4a71a723d, CONFIG_GPIOLIB was added as a dependency, defeating the original purpose of this option. Instead of that patch, the original commit could have just been reverted (and in fact was partially so in 403c1d0be5ccbd750d25c59d8358843a81e52e3b). Further, since this option has a dependency on HAS_IOMEM, even though it does not require it, it causes build failures when !HAS_IOMEM (e.g. in a uml build). Fix that by completely removing the option, in essence completing the reversion of the original commit. Signed-off-by: Keno Fischer <keno@juliacomputing.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: tc3589x: fix up .get_direction()Linus Walleij2016-11-151-1/+1
| | | | | | | | | | The bit in the TC3589x direction register is 0 for input and 1 for output, but the gpiolib expects the reverse. Fix up the logic. Cc: stable@vger.kernel.org Fixes: 14063d71e5e6 ("gpio: tc3589x: add .get_direction() and small cleanup") Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: do not double-check direction on sleeping chipsLinus Walleij2016-11-151-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | When locking a GPIO line as IRQ, we go to lengths to double-check that the line is really set as input before marking it as used for IRQ. This is not good on GPIO chips that can sleep, because this function is called in IRQ-safe context. Just skip this if it can't be checked quickly. Currently this happens on sleeping expanders such as STMPE or TC3589x: BUG: scheduling while atomic: swapper/1/0x00000002 Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 4.9.0-rc1+ #38 Hardware name: Nomadik STn8815 [<c000f2e0>] (unwind_backtrace) from [<c000d244>] (show_stack+0x10/0x14) [<c000d244>] (show_stack) from [<c0037b78>] (__schedule_bug+0x54/0x80) [<c0037b78>] (__schedule_bug) from [<c042df14>] (__schedule+0x3a0/0x460) [<c042df14>] (__schedule) from [<c042e028>] (schedule+0x54/0xb8) (...) This patch fixes that problem and relies on the direction read from the chip when it was added. Cc: stable@vger.kernel.org Fixes: 9c10280d85c1 ("gpio: flush direction status in gpiochip_lock_as_irq()") Cc: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: pca953x: Move memcpy into mutex lock for set multiplePhil Reid2016-11-081-2/+1
| | | | | | | | | | | Need to ensure that reg_output is not updated while setting multiple bits. This makes the mutex locking behaviour for the set_multiple call consistent with that of the set_value call. Cc: stable@vger.kernel.org Fixes: b4818afeacbd ("gpio: pca953x: Add set_multiple to allow multiple") Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: pca953x: Fix corruption of other gpios in set_multiple.Phil Reid2016-11-081-0/+1
| | | | | | | | | | | | gpiod_set_array_value_complex does not clear the bits field. Therefore when the drivers set_multiple funciton is called bits outside the mask are undefined and can be either set or not. So bank_val needs to be masked with bank_mask before or with the reg_val cache. Cc: stable@vger.kernel.org Fixes: b4818afeacbd ("gpio: pca953x: Add set_multiple to allow multiple") Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio/mvebu: Use irq_domain_add_linearJason Gunthorpe2016-11-011-49/+43
| | | | | | | | | | | | | | | | | | This fixes the irq allocation in this driver to not print: irq: Cannot allocate irq_descs @ IRQ34, assuming pre-allocated irq: Cannot allocate irq_descs @ IRQ66, assuming pre-allocated Which happens because the driver already called irq_alloc_descs() and so the change to use irq_domain_add_simple resulted in calling irq_alloc_descs() twice. Modernize the irq allocation in this driver to use the irq_domain_add_linear flow directly and eliminate the use of irq_domain_add_simple/legacy Fixes: ce931f571b6d ("gpio/mvebu: convert to use irq_domain_add_simple()") Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: of: fix GPIO drivers with multiple gpio_chip for a single nodeMasahiro Yamada2016-10-311-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sylvain Lemieux reports the LPC32xx GPIO driver is broken since commit 762c2e46c059 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data"). Probably, gpio-etraxfs.c and gpio-davinci.c are broken too. Those drivers register multiple gpio_chip that are associated to a single OF node, and their own .of_xlate() checks if the passed gpio_chip is valid. Now, the problem is of_find_gpiochip_by_node() returns the first gpio_chip found to match the given node. So, .of_xlate() fails, except for the first GPIO bank. Reverting the commit could be a solution, but I do not want to go back to the mess of struct gg_data. Another solution here is to take the match by a node pointer and the success of .of_xlate(). It is a bit clumsy to call .of_xlate twice; for gpio_chip matching and for really getting the gpio_desc index. Perhaps, our long-term goal might be to convert the drivers to single chip registration, but this commit will solve the problem until then. Fixes: 762c2e46c059 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data") Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reported-by: Sylvain Lemieux <slemieux.tyco@gmail.com> Tested-by: David Lechner <david@lechnology.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_LINE{HANDLE,EVENT}_IOCTL: Fix file descriptor leakLars-Peter Clausen2016-10-311-12/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When allocating a new line handle or event a file is allocated that it is associated to. The file is attached to a file descriptor of the current process and the file descriptor is returned to userspace using copy_to_user(). If this copy operation fails the line handle or event allocation is aborted, all acquired resources are freed and an error is returned. But the file struct is not freed and left attached to the userspace application and even though the file descriptor number was not copied it is trivial to guess. If a userspace application performs a IOCTL on such a left over file descriptor it will trigger a use-after-free and if the file descriptor is closed (latest when the application exits) a double-free is triggered. anon_inode_getfd() performs 3 tasks, allocate a file struct, allocate a file descriptor for the current process and install the file struct in the file descriptor. As soon as the file struct is installed in the file descriptor it is accessible by userspace (even if the IOCTL itself hasn't completed yet), this means uninstalling the fd on the error path is not an option, since userspace might already got a reference to the file. Instead anon_inode_getfd() needs to be broken into its individual steps. The allocation of the file struct and file descriptor is done first, then the copy_to_user() is executed and only if it succeeds the file is installed. Since the file struct is reference counted it can not be just freed, but its reference needs to be dropped, which will also call the release() callback, which will free the state attached to the file. So in this case the normal error cleanup path should not be taken. Cc: stable@vger.kernel.org Fixes: d932cd49182f ("gpio: free handles in fringe cases") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: mpc8xxx: Correct irq handler functionLiu Gang2016-10-241-1/+1
| | | | | | | | | | | | | | | From the beginning of the gpio-mpc8xxx.c, the "handle_level_irq" has being used to handle GPIO interrupts in the PowerPC/Layerscape platforms. But actually, almost all PowerPC/Layerscape platforms assert an interrupt request upon either a high-to-low change or any change on the state of the signal. So the "handle_level_irq" is not reasonable for PowerPC/Layerscape GPIO interrupt, it should be "handle_edge_irq". Otherwise the system may lost some interrupts from the PIN's state changes. Signed-off-by: Liu Gang <Gang.Liu@nxp.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: ath79: Fix module autoloadJavier Martinez Canillas2016-10-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Before this patch: $ modinfo drivers/gpio/gpio-ath79.ko | grep alias $ After this patch: $ modinfo drivers/gpio/gpio-ath79.ko | grep alias alias: of:N*T*Cqca,ar9340-gpioC* alias: of:N*T*Cqca,ar9340-gpio alias: of:N*T*Cqca,ar7100-gpioC* alias: of:N*T*Cqca,ar7100-gpio Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Acked-by: Aban Bedel <albeu@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: ts4800: Fix module autoloadJavier Martinez Canillas2016-10-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Before this patch: $ modinfo drivers/gpio/gpio-ts4800.ko | grep alias $ After this patch: $ modinfo drivers/gpio/gpio-ts4800.ko | grep alias alias: of:N*T*Ctechnologic,ts4800-gpioC* alias: of:N*T*Ctechnologic,ts4800-gpio Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_LINEEVENT_IOCTL: Reject invalid line and event flagsLars-Peter Clausen2016-10-211-0/+11
| | | | | | | | | | | | | | | | | | | | | | The GPIO_GET_LINEEVENT_IOCTL currently ignores unknown or undefined linehandle and lineevent flags. From a backwards and forwards compatibility viewpoint it is highly desirable to reject unknown flags though. On one hand an application that is using newer flags and is running on an older kernel has no way to detect if the new flags were handled correctly if they are silently discarded. On the other hand an application that (accidentally) passes undefined flags will run fine on an older kernel, but may break on a newer kernel when these flags get defined. Ensure that requests that have undefined flags set are rejected with an error, rather than silently discarding the undefined flags. Cc: stable@vger.kernel.org Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_LINEHANDLE_IOCTL: Reject invalid line flagsLars-Peter Clausen2016-10-211-0/+13
| | | | | | | | | | | | | | | | | | | | | | The GPIO_GET_LINEHANDLE_IOCTL currently ignores unknown or undefined linehandle flags. From a backwards and forwards compatibility viewpoint it is highly desirable to reject unknown flags though. On one hand an application that is using newer flags and is running on an older kernel has no way to detect if the new flags were handled correctly if they are silently discarded. On the other hand an application that (accidentally) passes undefined flags will run fine on an older kernel, but may break on a newer kernel when these flags get defined. Ensure that requests that have undefined flags set are rejected with an error, rather than silently discarding the undefined flags. Cc: stable@vger.kernel.org Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leakLars-Peter Clausen2016-10-211-0/+2
| | | | | | | | | | | | | | | | The GPIOHANDLE_GET_LINE_VALUES_IOCTL handler allocates a gpiohandle_data struct on the stack and then passes it to copy_to_user(). But depending on the number of requested line handles the struct is only partially initialized. This exposes the previous, potentially sensitive, stack content to the issuing userspace application. To avoid this make sure that the struct is fully initialized. Cc: stable@vger.kernel.org Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_LINEEVENT_IOCTL: Validate line offsetLars-Peter Clausen2016-10-211-0/+5
| | | | | | | | | | | | | | The line offset that is used as an index into the descs array is provided by userspace and might go beyond the bounds of the array. If that happens undefined behavior will occur. Make sure that the offset is within the bounds of the desc array and reject any requests that specify a value outside of it. Cc: stable@vger.kernel.org Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leakLars-Peter Clausen2016-10-211-0/+2
| | | | | | | | | | | | | | | | The GPIOHANDLE_GET_LINE_VALUES_IOCTL handler allocates a gpiohandle_data struct on the stack and then passes it to copy_to_user(). But only the first element of the values array in the struct is set, which leaves the struct partially initialized. This exposes the previous, potentially sensitive, stack content to the issuing userspace application. To avoid this make sure that the struct is fully initialized. Cc: stable@vger.kernel.org Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offsetLars-Peter Clausen2016-10-211-0/+5
| | | | | | | | | | | | | | The line offset that is used as an index into the descs array is provided by userspace and might go beyond the bounds of the array. If that happens undefined behavior will occur. Make sure that the offset is within the bounds of the desc array and reject any requests that specify a value outside of it. Cc: stable@vger.kernel.org Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_CHIPINFO_IOCTL: Fix information leakLars-Peter Clausen2016-10-211-0/+2
| | | | | | | | | | | | | | | The GPIO_GET_CHIPINFO_IOCTL handler allocates a gpiochip_info struct on the stack and then passes it to copy_to_user(). But depending on the length of the GPIO chip name and label the struct is only partially initialized. This exposes the previous, potentially sensitive, stack content to the issuing userspace application. To avoid this make sure that the struct is fully initialized. Cc: stable@vger.kernel.org Fixes: 521a2ad6f862 ("gpio: add userspace ABI for GPIO line information") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: GPIO_GET_CHIPINFO_IOCTL: Fix line offset validationLars-Peter Clausen2016-10-211-1/+1
| | | | | | | | | | | | | | The current line offset validation is off by one. Depending on the data stored behind the descs array this can either cause undefined behavior or disclose arbitrary, potentially sensitive, memory to the issuing userspace application. Make sure that offset is within the bounds of the desc array. Cc: stable@vger.kernel.org Fixes: 521a2ad6f862 ("gpio: add userspace ABI for GPIO line information") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: fix returned error from acpi_dev_gpio_irq_get()David Arcari2016-10-201-2/+5
| | | | | | | | | | | | | | acpi_dev_gpio_irq_get() currently ignores the error returned by acpi_get_gpiod_by_index() and overwrites it with -ENOENT. Problem is this error can be -EPROBE_DEFER, which just blows up some drivers when the module ordering is not correct. Cc: stable@vger.kernel.org Signed-off-by: David Arcari <darcari@redhat.com> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: mockup: add sysfs dependencyArnd Bergmann2016-10-201-1/+1
| | | | | | | | | | | | | Building the gpio-mockup driver without SYSFS results in a harmless Kconfig warning: warning: (GPIO_MOCKUP) selects GPIO_SYSFS which has unmet direct dependencies (GPIOLIB && SYSFS) We can easily avoid that warning by adding a dependency on SYSFS. Fixes: 0f98dd1b27d2 ("gpio/mockup: add virtual gpio device") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: stmpe: || vs && typoDan Carpenter2016-10-201-1/+1
| | | | | | | | | && was obviously intended here. Fixes: 6936e1f88d23 ('gpio: stmpe: Write int status register only when needed') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: mxs: Unmap region obtained by of_iomapArvind Yadav2016-10-201-2/+6
| | | | | | | Free memory mapping, if mxs_gpio_probe is not successful. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: pca953x: add a comment explaining the need for a lockdep subclassBartosz Golaszewski2016-10-111-0/+16
| | | | | | | | | | | | | | This is a follow-up to commit 559b46990e76 ("gpio: pca953x: fix an incorrect lockdep warning"). The reason for calling lockdep_set_subclass() in pca953x_probe() is not explained in the code. Add a comment describing the problem, partial solution and required future extensions. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* Merge branch 'i2c/for-4.9' of ↵Linus Torvalds2016-10-071-7/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "Here is the 4.9 pull request from I2C including: - centralized error messages when registering to the core - improved lockdep annotations to prevent false positives - DT support for muxes, gates, and arbitrators - bus speeds can now be obtained from ACPI - i2c-octeon got refactored and now supports ThunderX SoCs, too - i2c-tegra and i2c-designware got a bigger bunch of updates - a couple of standard driver fixes and improvements" * 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits) i2c: axxia: disable clks in case of failure in probe i2c: octeon: thunderx: Limit register access retries i2c: uniphier-f: fix misdetection of incomplete STOP condition gpio: pca953x: variable 'id' was used twice i2c: i801: Add support for Kaby Lake PCH-H gpio: pca953x: fix an incorrect lockdep warning i2c: add a warning to i2c_adapter_depth() lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible i2c: export i2c_adapter_depth() i2c: rk3x: Fix variable 'min_total_ns' unused warning i2c: rk3x: Fix sparse warning i2c / ACPI: Do not touch an I2C device if it belongs to another adapter i2c: octeon: Fix high-level controller status check i2c: octeon: Avoid sending STOP during recovery i2c: octeon: Fix set SCL recovery function i2c: rcar: add support for r8a7796 (R-Car M3-W) i2c: imx: make bus recovery through pinctrl optional i2c: meson: add gxbb compatible string i2c: uniphier-f: set the adapter to master mode when probing i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path ...
| * gpio: pca953x: variable 'id' was used twiceWolfram Sang2016-09-241-7/+7
| | | | | | | | | | | | | | | | | | | | | | sparse rightfully said: drivers/gpio/gpio-pca953x.c:771:45: warning: symbol 'id' shadows an earlier one drivers/gpio/gpio-pca953x.c:742:36: originally declared here So, name them explicitly 'i2c_id' and 'acpi_id' to avoid any confusion. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * gpio: pca953x: fix an incorrect lockdep warningBartosz Golaszewski2016-09-241-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an I2C GPIO multiplexer is driven by a GPIO provided by an expander when there's a second expander using the same device driver on one of the I2C bus segments, lockdep prints a deadlock warning when trying to set the direction or the value of the GPIOs provided by the second expander. The below diagram presents the setup: - - - - - ------- --------- Bus segment 1 | | | | | |--------------- Devices | | SCL/SDA | | | | | Linux |-----------| I2C MUX | - - - - - | | | | | Bus segment 2 | | | | |------------------- ------- | --------- | | | - - - - - ------------ | MUX GPIO | | | | | Devices | GPIO | | | | | Expander 1 |---- - - - - - | | | ------------ | SCL/SDA | ------------ | | | GPIO | | Expander 2 | | | ------------ The reason for lockdep warning is that we take the chip->i2c_lock in pca953x_gpio_set_value() or pca953x_gpio_direction_output() and then come right back to pca953x_gpio_set_value() when the GPIO mux kicks in. The locks actually protect different expanders, but for lockdep both are of the same class, so it says: Possible unsafe locking scenario: CPU0 ---- lock(&chip->i2c_lock); lock(&chip->i2c_lock); *** DEADLOCK *** May be due to missing lock nesting notation In order to get rid of the warning, retrieve the adapter nesting depth and use it as lockdep subclass for chip->i2c_lock. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Peter Rosin <peda@axentia.se> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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