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* gpio / ACPI: Prevent potential wrap of GPIO value on OpRegion readMika Westerberg2014-04-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | Dan Carpenter's static code checker reports: The patch 473ed7be0da0: "gpio / ACPI: Add support for ACPI GPIO operation regions" from Mar 14, 2014, leads to the following static checker warning: drivers/gpio/gpiolib-acpi.c:454 acpi_gpio_adr_space_handler() warn: should 'gpiod_get_raw_value(desc) << i' be a 64 bit type? This is due the fact that *value is of type u64 and gpiod_get_raw_value() returns int. Since i can be larger than 31, it is possible that the value returned gets wrapped. Fix this by casting the return of gpiod_get_raw_value() to u64 first before shift. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: Don't crash on NULL chip->devMika Westerberg2014-04-141-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit aa92b6f689ac (gpio / ACPI: Allocate ACPI specific data directly in acpi_gpiochip_add()) moved ACPI handle checking to acpi_gpiochip_add() but forgot to check whether chip->dev is NULL before dereferencing it. Since chip->dev pointer is optional we can end up with crash like following: BUG: unable to handle kernel NULL pointer dereference at 00000138 IP: [<c126c2b3>] acpi_gpiochip_add+0x13/0x190 *pde = 00000000 Oops: 0000 [#1] PREEMPT SMP Modules linked in: ssb(+) ... CPU: 0 PID: 512 Comm: modprobe Tainted: G W 3.14.0-rc7-next-20140324-t1 #24 Hardware name: Dell Inc. Latitude D830 /0UY141, BIOS A02 06/07/2007 task: f5799900 ti: f543e000 task.ti: f543e000 EIP: 0060:[<c126c2b3>] EFLAGS: 00010282 CPU: 0 EIP is at acpi_gpiochip_add+0x13/0x190 EAX: 00000000 EBX: f57824c4 ECX: 00000000 EDX: 00000000 ESI: f57824c4 EDI: 00000010 EBP: f543fc54 ESP: f543fc40 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 8005003b CR2: 00000138 CR3: 355f8000 CR4: 000007d0 Stack: f543fc5c fd1f7790 f57824c4 000000be 00000010 f543fc84 c1269f4e f543fc74 fd1f78bd 00008002 f57822b0 f5782090 fd1f8400 00000286 fd1f9994 00000000 f5782000 f543fc8c fd1f7e39 f543fcc8 fd1f0bd8 000000c0 00000000 00000000 Call Trace: [<fd1f7790>] ? ssb_pcie_mdio_write+0xa0/0xd0 [ssb] [<c1269f4e>] gpiochip_add+0xee/0x300 [<fd1f78bd>] ? ssb_pcicore_serdes_workaround+0xfd/0x140 [ssb] [<fd1f7e39>] ssb_gpio_init+0x89/0xa0 [ssb] [<fd1f0bd8>] ssb_attach_queued_buses+0xc8/0x2d0 [ssb] [<fd1f0f65>] ssb_bus_register+0x185/0x1f0 [ssb] [<fd1f3120>] ? ssb_pci_xtal+0x220/0x220 [ssb] [<fd1f106c>] ssb_bus_pcibus_register+0x2c/0x80 [ssb] [<fd1f40dc>] ssb_pcihost_probe+0x9c/0x110 [ssb] [<c1276c8f>] pci_device_probe+0x6f/0xc0 [<c11bdb55>] ? sysfs_create_link+0x25/0x40 [<c131d8b9>] driver_probe_device+0x79/0x360 [<c1276512>] ? pci_match_device+0xb2/0xc0 [<c131dc51>] __driver_attach+0x71/0x80 [<c131dbe0>] ? __device_attach+0x40/0x40 [<c131bd87>] bus_for_each_dev+0x47/0x80 [<c131d3ae>] driver_attach+0x1e/0x20 [<c131dbe0>] ? __device_attach+0x40/0x40 [<c131d007>] bus_add_driver+0x157/0x230 [<c131e219>] driver_register+0x59/0xe0 ... Fix this by checking chip->dev pointer against NULL first. Also we can now remove redundant check in acpi_gpiochip_request/free_interrupts(). Reported-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Tested-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: Add support for ACPI GPIO operation regionsMika Westerberg2014-03-141-0/+163
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GPIO operation regions is a new feature introduced in ACPI 5.0 specification. This feature adds a way for platform ASL code to call back to OS GPIO driver and toggle GPIO pins. An example ASL code from Lenovo Miix 2 tablet with only relevant part listed: Device (\_SB.GPO0) { Name (AVBL, Zero) Method (_REG, 2, NotSerialized) { If (LEqual (Arg0, 0x08)) { // Marks the region available Store (Arg1, AVBL) } } OperationRegion (GPOP, GeneralPurposeIo, Zero, 0x0C) Field (GPOP, ByteAcc, NoLock, Preserve) { Connection ( GpioIo (Exclusive, PullDefault, 0, 0, IoRestrictionOutputOnly, "\\_SB.GPO0", 0x00, ResourceConsumer,,) { 0x003B } ), SHD3, 1, } } Device (SHUB) { Method (_PS0, 0, Serialized) { If (LEqual (\_SB.GPO0.AVBL, One)) { Store (One, \_SB.GPO0.SHD3) Sleep (0x32) } } Method (_PS3, 0, Serialized) { If (LEqual (\_SB.GPO0.AVBL, One)) { Store (Zero, \_SB.GPO0.SHD3) } } } How this works is that whenever _PS0 or _PS3 method is run (typically when SHUB device is transitioned to D0 or D3 respectively), ASL code checks if the GPIO operation region is available (\_SB.GPO0.AVBL). If it is we go and store either 0 or 1 to \_SB.GPO0.SHD3. Now, when ACPICA notices ACPI GPIO operation region access (the store above) it will call acpi_gpio_adr_space_handler() that then toggles the GPIO accordingly using standard gpiolib interfaces. Implement the support by registering GPIO operation region handlers for all GPIO devices that have an ACPI handle. First time the GPIO is used by the ASL code we make sure that the GPIO stays requested until the GPIO chip driver itself is unloaded. If we find out that the GPIO is already requested we just toggle it according to the value got from ASL code. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: Rework ACPI GPIO event handlingMika Westerberg2014-03-131-85/+129
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The current ACPI GPIO event handling code was never tested against real hardware with functioning GPIO triggered events (at the time such hardware wasn't available). Thus it misses certain things like requesting the GPIOs properly, passing correct flags to the interrupt handler and so on. This patch reworks ACPI GPIO event handling so that we: 1) Use struct acpi_gpio_event for all GPIO signaled events. 2) Switch to use GPIO descriptor API and request GPIOs by calling gpiochip_request_own_desc() that we added in a previous patch. 3) Pass proper flags from ACPI GPIO resource to request_threaded_irq(). Also instead of open-coding the _AEI iteration loop we can use acpi_walk_resources(). This simplifies the code a bit and fixes memory leak that was caused by missing kfree() for buffer returned by acpi_get_event_resources(). Since the remove path now calls gpiochip_free_own_desc() which takes GPIO spinlock we need to call acpi_gpiochip_remove() outside of that lock (analogous to acpi_gpiochip_add() path where the lock is released before those funtions are called). Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: Rename acpi_gpio_evt_pin to acpi_gpio_eventMika Westerberg2014-03-131-20/+19
| | | | | | | | | | | In order to consolidate _Exx, _Lxx and _EVT to use the same structure make the structure name to reflect that we are dealing with any event, not just _EVT. This is just rename, no functional changes. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: Allocate ACPI specific data directly in acpi_gpiochip_add()Mika Westerberg2014-03-131-42/+64
| | | | | | | | | | | | | | | | | We are going to add more ACPI specific data to accompany GPIO chip so instead of allocating it per each use-case we allocate it once when acpi_gpiochip_add() is called and release it when acpi_gpiochip_remove() is called. Doing this allows us to add more ACPI specific data by merely adding new fields to struct acpi_gpio_chip. In addition we embed evt_pins member directly to the structure instead of having it as a pointer. This simplifies the code a bit since we don't need to check against NULL. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib: ACPI: remove gpio_to_desc() usageAlexandre Courbot2014-02-121-1/+1
| | | | | | | | | gpio_to_desc() must die. Replace one of its usage by the newly-introduced gpiochip_get_desc() function. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: get rid of acpi_gpio.hMika Westerberg2014-01-081-2/+3
| | | | | | | | | | | | | | Now that all users of acpi_gpio.h have been moved to use either the GPIO descriptor interface or to the internal gpiolib.h we can get rid of acpi_gpio.h entirely. Once this is done the only interface to get GPIOs to drivers enumerated from ACPI namespace is the descriptor based interface. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: register to ACPI events automaticallyMika Westerberg2014-01-081-4/+12
| | | | | | | | | | | | | | | | | | Instead of asking each driver to register to ACPI events we can just call acpi_gpiochip_register_interrupts() for each chip that has an ACPI handle. The function checks chip->to_irq and if it is set to NULL (a GPIO driver that doesn't do interrupts) the function does nothing. We also add the a new header drivers/gpio/gpiolib.h that is used for functions internal to gpiolib and add ACPI GPIO chip registering functions to that header. Once that is done we can remove call to acpi_gpiochip_register_interrupts() from its only user, pinctrl-baytrail.c Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: return -ENOENT when no mapping existsMika Westerberg2013-12-121-1/+1
| | | | | | | | | | | Doing this allows drivers to distinguish between a real error case (if there was an error when we tried to resolve the GPIO) and when the optional GPIO line was not available. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resourcesMika Westerberg2013-10-191-0/+2
| | | | | | | | | | | | The ACPI GpioInt resources contain polarity field that is used to specify whether the interrupt is active high or low. Since gpiolib supports GPIOF_ACTIVE_LOW we can pass this information in the flags field in acpi_find_gpio(), analogous to the DeviceTree version. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib / ACPI: convert to gpiod interfacesMika Westerberg2013-10-191-26/+25
| | | | | | | | | | | | | | | | The new GPIO descriptor based interface is now preferred over the old integer based one. This patch converts the ACPI GPIO helpers to use this new interface internally. In addition to that provide compatibility function acpi_get_gpio_by_index() that converts the returned GPIO descriptor to an integer. We also drop acpi_get_gpio() as it is not used anywhere outside gpiolib-acpi and even there we use acpi_get_gpiod() instead. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib / ACPI: move acpi_gpiochip_free_interrupts next to the request functionMika Westerberg2013-10-111-38/+38
| | | | | | | | | It makes more sense to have these functions close to each other. No functional changes. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib-acpi: convert acpi_evaluate_object() to acpi_execute_simple_method()Zhang Rui2013-09-171-8/+1
| | | | | | | | | | | | | acpi_execute_simple_method() is a new ACPI API introduced to invoke an ACPI control method that has single integer parameter and no return value. Convert acpi_evaluate_object() to acpi_execute_simple_method() in drivers/gpio/gpiolib-acpi.c Signed-off-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib-acpi: introduce acpi_get_gpio_by_index() helperMika Westerberg2013-04-121-0/+77
| | | | | | | | | | | | | Instead of open-coding ACPI GPIO resource lookup in each driver, we provide a helper function analogous to Device Tree version that allows drivers to specify which GPIO resource they are interested (using an index to the GPIO resources). The function then finds out the correct resource, translates the ACPI GPIO number to the corresponding Linux GPIO number and returns that. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: Handle ACPI events in accordance with the specRafael J. Wysocki2013-04-101-20/+120
| | | | | | | | | | | | | | | | | | | | | | | | Commit 0d1c28a (gpiolib-acpi: Add ACPI5 event model support to gpio.) that added support for ACPI events signalled through GPIO interrupts covered only GPIO pins whose numbers are less than or equal to 255. However, there may be GPIO pins with numbers greater than 255 and the ACPI spec (ACPI 5.0, Section 5.6.5.1) requires the _EVT method to be used for handling events corresponding to those pins. Moreover, according to the spec, _EVT is the default mechanism for handling all ACPI events signalled through GPIO interrupts, so if the _Exx/_Lxx method is not present for the given pin, _EVT should be used instead. If present, though, _Exx/_Lxx take precedence over _EVT which shouldn't be executed in that case (ACPI 5.0, Section 5.6.5.3). Modify acpi_gpiochip_request_interrupts() to follow the spec as described above and add acpi_gpiochip_free_interrupts() needed to free interrupts associated with _EVT. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib-acpi: Fix error checks in interrupt requestingMathias Nyman2013-02-041-2/+7
| | | | | | | | Print error message if requesting an interrupt fails. Use int instead of unsigned for interrupts in case of error values Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib-acpi: Add ACPI5 event model support to gpio.Mathias Nyman2013-01-291-0/+82
| | | | | | | | | | | | | | | Add ability to handle ACPI events signalled by GPIO interrupts. ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are handled by ACPI event methods which need to be called from the GPIO controller's interrupt handler. acpi_gpio_request_interrupt() finds out which gpio pins have acpi event methods and assigns interrupt handlers that calls the acpi event methods for those pins. Partially based on work by Rui Zhang <rui.zhang@intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
* gpio / ACPI: add ACPI supportMathias Nyman2012-11-301-0/+54
Add support for translating ACPI GPIO pin numbers to Linux GPIO API pins. Needs a gpio controller driver with the acpi handler hook set. Drivers can use acpi_get_gpio() to translate ACPI5 GpioIO and GpioInt resources to Linux GPIO's. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>