linux/drivers/gpio
Benjamin Tissoires ca876c7483 gpiolib-acpi: make sure we trigger edge events at least once on boot
On some systems using edge triggered ACPI Event Interrupts, the initial
state at boot is not setup by the firmware, instead relying on the edge
irq event handler running at least once to setup the initial state.

2 known examples of this are:

1) The Surface 3 has its _LID state controlled by an ACPI operation region
 triggered by a GPIO event:

 OperationRegion (GPOR, GeneralPurposeIo, Zero, One)
 Field (GPOR, ByteAcc, NoLock, Preserve)
 {
     Connection (
         GpioIo (Shared, PullNone, 0x0000, 0x0000, IoRestrictionNone,
             "\\_SB.GPO0", 0x00, ResourceConsumer, ,
             )
             {   // Pin list
                 0x004C
             }
     ),
     HELD,   1
 }

 Method (_E4C, 0, Serialized)  // _Exx: Edge-Triggered GPE
 {
     If ((HELD == One))
     {
         ^^LID.LIDB = One
     }
     Else
     {
         ^^LID.LIDB = Zero
         Notify (LID, 0x80) // Status Change
     }

     Notify (^^PCI0.SPI1.NTRG, One) // Device Check
 }

 Currently, the state of LIDB is wrong until the user actually closes or
 open the cover. We need to trigger the GPIO event once to update the
 internal ACPI state.

 Coincidentally, this also enables the Surface 2 integrated HID sensor hub
 which also requires an ACPI gpio operation region to start initialization.

2) Various Bay Trail based tablets come with an external USB mux and
 TI T1210B USB phy to enable USB gadget mode. The mux is controlled by a
 GPIO which is controlled by an edge triggered ACPI Event Interrupt which
 monitors the micro-USB ID pin.

 When the tablet is connected to a PC (or no cable is plugged in), the ID
 pin is high and the tablet should be in gadget mode. But the GPIO
 controlling the mux is initialized by the firmware so that the USB data
 lines are muxed to the host controller.

 This means that if the user wants to use gadget mode, the user needs to
 first plug in a host-cable to force the ID pin low and then unplug it
 and connect the tablet to a PC, to get the ACPI event handler to run and
 switch the mux to device mode,

This commit fixes both by running the event-handler once on boot.

Note that the running of the event-handler is done from a late_initcall,
this is done because the handler AML code may rely on OperationRegions
registered by other builtin drivers. This avoids errors like these:

[    0.133026] ACPI Error: No handler for Region [XSCG] ((____ptrval____)) [GenericSerialBus] (20180531/evregion-132)
[    0.133036] ACPI Error: Region GenericSerialBus (ID=9) has no handler (20180531/exfldio-265)
[    0.133046] ACPI Error: Method parse/execution failed \_SB.GPO2._E12, AE_NOT_EXIST (20180531/psparse-516)

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
[hdegoede: Document BYT USB mux reliance on initial trigger]
[hdegoede: Run event handler from a late_initcall, rather then immediately]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-01 11:45:10 +02:00
..
devres.c gpio: Export devm_gpiod_get_from_of_node() for consumers 2018-01-12 11:05:24 +01:00
gpio-74x164.c The is the bulk of GPIO changes for the v4.16 kernel cycle. 2018-01-31 12:25:27 -08:00
gpio-74xx-mmio.c gpio: 74xx-mmio: Use of_device_get_match_data() 2018-05-16 14:35:24 +02:00
gpio-104-dio-48e.c gpio: 104-dio-48e: make array 'ports' static, shrinks object size 2018-05-16 14:35:24 +02:00
gpio-104-idi-48.c gpio: make several const arrays static, shrinks object size 2018-05-16 14:35:24 +02:00
gpio-104-idio-16.c gpio: 104-idio-16: Implement get_multiple callback 2018-03-26 10:10:18 +02:00
gpio-adnp.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpio-adp5520.c gpio: adp5520: Include proper header 2018-01-13 22:12:07 +01:00
gpio-adp5588.c gpio: adp5588: Include proper header 2018-01-13 22:14:56 +01:00
gpio-altera-a10sr.c gpio: altera-a10sr: constify gpio_chip structure 2017-08-14 15:01:12 +02:00
gpio-altera.c gpio: altera: Include GPIO driver header 2018-01-13 22:18:34 +01:00
gpio-amd8111.c gpio: amd8111: Include proper header 2018-01-13 22:22:49 +01:00
gpio-amdpt.c
gpio-arizona.c gpio: arizona: Include proper header 2018-01-13 22:47:48 +01:00
gpio-aspeed.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpio-ath79.c gpio: ath79: Fix potential NULL dereference in ath79_gpio_probe() 2018-03-27 15:42:29 +02:00
gpio-bcm-kona.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpio-bd9571mwv.c gpio: Add ROHM BD9571MWV-M PMIC GPIO driver 2017-04-28 09:47:46 +02:00
gpio-brcmstb.c The is the bulk of GPIO changes for the v4.16 kernel cycle. 2018-01-31 12:25:27 -08:00
gpio-bt8xx.c gpio: bt8xx: Include proper header 2018-01-13 22:56:52 +01:00
gpio-clps711x.c
gpio-crystalcove.c gpio: crystalcove: Include proper header 2018-01-14 01:48:48 +01:00
gpio-cs5535.c gpio: cs5535: Include proper header 2018-01-14 01:56:24 +01:00
gpio-da9052.c gpio: da905x: Include proper header 2018-01-14 02:00:10 +01:00
gpio-da9055.c gpio: da905x: Include proper header 2018-01-14 02:00:10 +01:00
gpio-davinci.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpio-dln2.c gpio: dln2: Include proper header 2018-03-19 01:50:07 +01:00
gpio-dwapb.c gpio: dwapb: Rework support for 1 interrupt per port A GPIO 2018-05-23 11:30:13 +02:00
gpio-eic-sprd.c gpio: eic: Add edge trigger emulation for EIC 2018-05-16 14:35:24 +02:00
gpio-em.c gpio: em: Use the right include 2018-03-19 01:50:07 +01:00
gpio-ep93xx.c pinctrl / gpio: Introduce .set_config() callback for GPIO chips 2017-01-26 15:27:37 +01:00
gpio-exar.c gpio: exar: Use correct property prefix and document bindings 2017-08-01 13:43:55 +02:00
gpio-f7188x.c gpio: f7188x: Add a missing break 2017-04-28 10:09:16 +02:00
gpio-ftgpio010.c gpio: ftgpio010: Drop of_gpio.h include 2018-03-19 01:50:24 +01:00
gpio-ge.c gpio: ge: Fix build warning 2018-05-16 14:35:24 +02:00
gpio-gpio-mm.c gpio: make several const arrays static, shrinks object size 2018-05-16 14:35:24 +02:00
gpio-grgpio.c gpio: grgpio: Include the right header 2018-03-19 01:50:28 +01:00
gpio-hlwd.c gpio: Add GPIO driver for Nintendo Wii 2018-02-22 13:54:35 +01:00
gpio-htc-egpio.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpio-ich.c gpio: ich: Use BIT() macro 2018-03-19 01:50:29 +01:00
gpio-ingenic.c gpio: ingenic: Use of_device_get_match_data() 2018-05-16 14:35:24 +02:00
gpio-intel-mid.c gpio-intel-mid: Delete an error message 2018-02-22 15:29:05 +01:00
gpio-iop.c gpio: iop: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE 2017-12-02 22:42:21 +01:00
gpio-it87.c gpio: it87: Include the right header 2018-03-19 01:50:29 +01:00
gpio-janz-ttl.c gpio: janz-ttl: Use BIT() macro 2018-03-19 01:50:30 +01:00
gpio-kempld.c gpio: kempld: Include the right header 2018-03-19 01:50:31 +01:00
gpio-ks8695.c gpio: ks8695: Include the right header 2018-03-19 01:50:31 +01:00
gpio-loongson1.c gpio: loongson1: fix bgpio usage 2017-10-25 11:25:38 +02:00
gpio-loongson.c gpio: loongson: Use BIT() macros 2018-05-16 14:35:24 +02:00
gpio-lp873x.c gpio: lp873x: Include the right header 2018-05-16 14:35:24 +02:00
gpio-lp3943.c gpio: lp3943: Include the right header 2018-05-16 14:35:24 +02:00
gpio-lp87565.c gpio: lp87565: Set proper output level and direction for direction_output 2017-07-31 15:26:57 +02:00
gpio-lpc18xx.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-lpc32xx.c gpio: lpc32xx: Include the right header 2018-05-16 14:35:24 +02:00
gpio-lynxpoint.c gpio: lynxpoint: Include the right header 2018-05-16 14:35:24 +02:00
gpio-max730x.c gpio: max730x: Include the right header 2018-05-16 14:35:24 +02:00
gpio-max732x.c gpio: max732x: Remove duplicate NULL check 2017-11-29 13:25:23 +01:00
gpio-max3191x.c gpio: Remove VLA from MAX3191X driver 2018-03-27 15:18:06 +02:00
gpio-max7300.c
gpio-max7301.c
gpio-max77620.c gpio: max77620: Make regmap_irq_chip const 2017-08-14 16:06:24 +02:00
gpio-mb86s7x.c gpio: mb86s70: Revert "Return error if requesting an already assigned gpio" 2017-10-31 13:13:34 +01:00
gpio-mc9s08dz60.c gpio: mc9s08dz60: Include the right header 2018-05-16 14:35:24 +02:00
gpio-mc33880.c gpio: mc33880: Include the right header 2018-05-16 14:35:24 +02:00
gpio-menz127.c pinctrl / gpio: Introduce .set_config() callback for GPIO chips 2017-01-26 15:27:37 +01:00
gpio-merrifield.c gpio: merrifield: Delete an error message 2018-02-22 15:25:40 +01:00
gpio-ml-ioh.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
gpio-mm-lantiq.c gpio: mm-lantiq: Include the right header 2018-05-16 14:35:24 +02:00
gpio-mmio.c gpio: mmio: Also read bits that are zero 2018-01-16 23:42:36 +01:00
gpio-mockup.c gpio: mockup: use the SPDX identifier and remove license boilerplate 2018-05-16 14:35:24 +02:00
gpio-mpc8xxx.c gpio: mpc8xxx: Do not reverse bits using bgpio 2017-10-25 11:25:40 +02:00
gpio-mpc5200.c
gpio-msic.c gpio: msic: Include the right header 2018-05-16 14:35:24 +02:00
gpio-mvebu.c gpio: mvebu: Use the proper APIs 2018-05-16 14:35:24 +02:00
gpio-mxc.c gpio: mxc: Switch to SPDX identifier 2018-05-24 10:14:30 +02:00
gpio-mxs.c gpio: mxs: Switch to SPDX identifier 2018-05-24 13:43:56 +02:00
gpio-octeon.c gpio: octeon: Include the right header 2018-05-24 14:22:04 +02:00
gpio-omap.c gpio: omap: Include the right header 2018-05-24 14:24:00 +02:00
gpio-palmas.c gpio: palmas: Include the right header 2018-05-24 14:25:13 +02:00
gpio-pca953x.c gpio: pca953x: Include the right header 2018-05-24 17:09:41 +02:00
gpio-pcf857x.c gpio: pcf857x: Include the right header 2018-05-24 17:09:41 +02:00
gpio-pch.c gpio: pch: Include the right header 2018-05-24 17:09:41 +02:00
gpio-pci-idio-16.c gpio: pci-idio-16: Fix port memory offset for get_multiple callback 2018-04-27 00:55:16 +02:00
gpio-pcie-idio-24.c gpio: pcie-idio-24: Fix off-by-one error in get_multiple loop 2018-04-30 10:48:08 +02:00
gpio-pisosr.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-pl061.c gpio: pl061: Include the right header 2018-05-24 17:09:41 +02:00
gpio-pmic-eic-sprd.c gpio: pmic_eic: Add edge trigger emulation for PMIC EIC 2018-05-16 14:35:24 +02:00
gpio-pxa.c gpio: pxa: Include the right header 2018-05-24 17:09:41 +02:00
gpio-raspberrypi-exp.c gpio: raspberrypi-exp: Driver for RPi3 GPIO expander via mailbox service 2018-02-22 13:49:59 +01:00
gpio-rc5t583.c
gpio-rcar.c Linux 4.16-rc5 2018-03-18 17:48:59 +01:00
gpio-rdc321x.c
gpio-reg.c gpio: gpio-reg: fix build 2017-12-22 15:24:31 +01:00
gpio-sa1100.c gpio: sa1100: implement get_direction method 2017-03-24 14:04:37 +01:00
gpio-sch311x.c
gpio-sch.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-sodaville.c gpio: sodaville: use resource management for irqs 2017-03-15 11:16:36 +01:00
gpio-spear-spics.c gpio: spear-spics: drop unused MODULE_ tags from non-modular code 2016-08-23 11:23:41 +02:00
gpio-sprd.c gpio: Add GPIO driver for Spreadtrum SC9860 platform 2018-03-02 11:00:43 +01:00
gpio-sta2x11.c gpio: sta2x11: use devres for irq generic chip 2017-08-21 00:06:04 +02:00
gpio-stmpe.c gpio: Remove VLA from stmpe driver 2018-05-24 10:22:21 +02:00
gpio-stp-xway.c gpio: update my email address 2016-12-30 09:18:10 +01:00
gpio-syscon.c gpio: syscon: allow fetching syscon from parent node 2018-05-23 10:07:26 +02:00
gpio-tb10x.c gpio: tb10x: Handle return value of devm_kasprintf 2017-09-21 14:14:17 +02:00
gpio-tc3589x.c gpio: Move irqdomain into struct gpio_irq_chip 2017-11-08 14:06:21 +01:00
gpio-tegra186.c gpio: tegra186: Remove tegra186_gpio_lock_class 2017-11-13 11:43:10 +01:00
gpio-tegra.c gpio: tegra: Convert to use DEFINE_SHOW_ATTRIBUTE macro 2018-02-22 15:25:40 +01:00
gpio-thunderx.c treewide: devm_kzalloc() -> devm_kcalloc() 2018-06-12 16:19:22 -07:00
gpio-timberdale.c gpio: timberdale: Improve a size determination 2018-02-22 15:14:58 +01:00
gpio-tpic2810.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-tps6586x.c
gpio-tps65086.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-tps65218.c pinctrl / gpio: Introduce .set_config() callback for GPIO chips 2017-01-26 15:27:37 +01:00
gpio-tps65910.c
gpio-tps65912.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-tps68470.c gpio: tps68470: Update to SPDX license identifier 2018-02-23 15:26:42 +01:00
gpio-ts4800.c gpio: ts4800: Fix module autoload 2016-10-21 14:55:07 +02:00
gpio-ts4900.c gpio: ts4900: Use of_device_get_match_data() 2018-05-16 14:35:24 +02:00
gpio-ts5500.c
gpio-twl4030.c mfd: twl: Move header file out of I2C realm 2017-09-04 14:41:02 +01:00
gpio-twl6040.c gpio: twl6040: remove unneeded forward declaration 2017-08-23 10:20:16 +02:00
gpio-ucb1400.c
gpio-uniphier.c gpio: uniphier: set legitimate irq trigger type in .to_irq hook 2018-07-23 23:13:31 +02:00
gpio-vf610.c gpio: vf610: Use of_device_get_match_data() 2018-05-16 14:35:24 +02:00
gpio-viperboard.c
gpio-vr41xx.c
gpio-vx855.c pinctrl / gpio: Introduce .set_config() callback for GPIO chips 2017-01-26 15:27:37 +01:00
gpio-wcove.c gpio: Move irqdomain into struct gpio_irq_chip 2017-11-08 14:06:21 +01:00
gpio-winbond.c gpio: winbond: Add driver 2018-01-09 14:51:00 +01:00
gpio-wm831x.c gpio-wm831x: Use seq_putc() in wm831x_gpio_dbg_show() 2018-02-12 09:36:06 +01:00
gpio-wm8350.c gpio: constify gpio_chip structures 2016-09-13 10:35:56 +02:00
gpio-wm8994.c pinctrl / gpio: Introduce .set_config() callback for GPIO chips 2017-01-26 15:27:37 +01:00
gpio-ws16c48.c gpio: ws16c48: Implement get_multiple callback 2018-03-26 10:28:19 +02:00
gpio-xgene-sb.c genirq/irqdomain: Rename early argument of irq_domain_activate_irq() 2017-12-29 21:13:04 +01:00
gpio-xgene.c gpio: xgene: mark PM functions as __maybe_unused 2017-03-06 14:35:22 +01:00
gpio-xilinx.c gpio: Convert to using %pOF instead of full_name 2017-08-14 15:01:12 +02:00
gpio-xlp.c gpio: xlp: Use of_device_get_match_data() 2018-05-16 14:35:24 +02:00
gpio-xra1403.c gpio: xra1403: Switch to a fixed upper bound for registers 2018-04-27 01:06:21 +02:00
gpio-xtensa.c
gpio-zevio.c gpio: zevio: make gpio_chip const 2017-08-23 09:21:54 +02:00
gpio-zx.c gpio: Move irqdomain into struct gpio_irq_chip 2017-11-08 14:06:21 +01:00
gpio-zynq.c gpio: zynq: Setup chip->base based on alias ID 2018-05-23 11:43:03 +02:00
gpiolib-acpi.c gpiolib-acpi: make sure we trigger edge events at least once on boot 2018-08-01 11:45:10 +02:00
gpiolib-devprop.c gpio: fix "gpio-line-names" property retrieval 2017-12-22 15:24:31 +01:00
gpiolib-legacy.c Revert "gpiolib: Split GPIO flags parsing and GPIO configuration" 2016-07-04 16:51:29 +02:00
gpiolib-of.c gpio: of: Handle fixed regulator flags properly 2018-07-23 23:13:31 +02:00
gpiolib-sysfs.c gpio: sysfs: avoid using kstrtol() in 'value' attribute write 2017-12-20 10:34:58 +01:00
gpiolib.c This is the bulk of GPIO changes for the v4.18 development 2018-06-08 10:31:52 -07:00
gpiolib.h gpio: Remove VLA from gpiolib 2018-05-23 14:01:03 +02:00
Kconfig gpio: Remove VLA from gpiolib 2018-05-23 14:01:03 +02:00
Makefile This is the bulk of GPIO changes for the v4.17 kernel cycle: 2018-04-05 09:51:41 -07:00