linux-toradex.git/drivers/pinctrl/intel/pinctrl-intel.c, branch v4.9

pinctrl: intel: Only restore pins that are used by the driver

2016-10-18T12:38:16+00:00

Dell XPS 13 (and maybe some others) uses a GPIO (CPU_GP_1) during suspend
to explicitly disable USB touchscreen interrupt. This is done to prevent
situation where the lid is closed the touchscreen is left functional.

The pinctrl driver (wrongly) assumes it owns all pins which are owned by
host and not locked down. It is perfectly fine for BIOS to use those pins
as it is also considered as host in this context.

What happens is that when the lid of Dell XPS 13 is closed, the BIOS
configures CPU_GP_1 low disabling the touchscreen interrupt. During resume
we restore all host owned pins to the known state which includes CPU_GP_1
and this overwrites what the BIOS has programmed there causing the
touchscreen to fail as no interrupts are reaching the CPU anymore.

Fix this by restoring only those pins we know are explicitly requested by
the kernel one way or other.

Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=176361
Reported-by: AceLan Kao 
Tested-by: AceLan Kao 
Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij

pinctrl: intel: Configure GPIO chip IRQ as wakeup interrupts

2016-09-23T13:14:21+00:00

On some Intel BXT platform, wake-up from suspend-to-idle on pressing
power-button is not working. Its noticed that gpio-keys driver marking the
second level IRQ/power-button as wake capable but Intel pintctrl
driver is missing to mark GPIO chip/controller IRQ which first level IRQ
as wake cable if its GPIO pin IRQ is wakeble. So, though the first level
IRQ gets generated on power-button press, since it is not marked as
wake capable resume/wake-up flow is not happening.
Intel pintctrl/GPIO driver need to mark GPIO chip/controller IRQ (first
level IRQ) as wake capable iff GPIO pin's IRQ (second level IRQ) is marked
as wake cable.

Changes in v2:
 - Add missing irq initialisation.

Signed-off-by: Nilesh Bacchewar 
Reviewed-by: Mika Westerberg 
Signed-off-by: Linus Walleij

pinctrl: intel: Protect set wake flow by spin lock

2016-07-11T09:15:33+00:00

It seems intel_gpio_irq_wake() misses lock protection against I/O flow.
Use spin lock here as well.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg 
Signed-off-by: Linus Walleij

pinctrl: intel: Prevent force threading of the interrupt handler

2016-06-18T08:35:47+00:00

The pinctrl-intel needs to use request_irq() instead of chained interrupt
handling because it shares the interrupt with multiple GPIO host
controllers found on Intel CPUs. In -rt all such interrupts are forced to
run in thread context which triggers following warning:

 WARNING: CPU: 0 PID: 530 at kernel/irq/handle.c:151 handle_irq_event_percpu+0x23d/0x240
 irq 348 handler irq_default_primary_handler+0x0/0x10 enabled interrupts
 Modules linked in:
 CPU: 0 PID: 530 Comm: irq/14-INT3452: Not tainted 4.6.2-rt5 #1060
  0000000000000000 ffff88007a257c98 ffffffff812d8494 ffff88007a257ce8
  0000000000000000 ffff88007a257cd8 ffffffff8105e554 000000977a257d90
  ffff88007a37a380 000000000000015c 0000000000000002 0000000000000000
 Call Trace:
  [] dump_stack+0x4f/0x6b
  [] __warn+0xe4/0x100
  [] warn_slowpath_fmt+0x4f/0x60
  [] ? __synchronize_hardirq+0x60/0x60
  [] handle_irq_event_percpu+0x23d/0x240
  [] handle_irq_event+0x62/0x90
  [] handle_edge_irq+0x8f/0x190
  [] generic_handle_irq+0x22/0x30
  [] intel_gpio_irq+0xdc/0x150
  [] irq_forced_thread_fn+0x23/0x70
  [] irq_thread+0x13b/0x1d0
  [] ? __schedule+0x2e4/0x5a0
  [] ? irq_finalize_oneshot.part.37+0xd0/0xd0
  [] ? irq_thread+0x1d0/0x1d0
  [] ? wake_threads_waitq+0x30/0x30
  [] kthread+0xd4/0xf0
  [] ? _raw_spin_unlock_irq+0x17/0x40
  [] ret_from_fork+0x22/0x40
  [] ? kthread_worker_fn+0x190/0x190

The handle_irq_event_* functions (and I suppose generic_handle_irq()) is
expected to be called with interrupts disabled and they rightfully complain
here because we run in thread context with interrupts enabled.

Fix this by adding IRQF_NO_THREAD flag when the master interrupt is
requested. This prevents forced threading of the interrupt used by the GPIO
host controllers.

Reported-by: Kim Tatt Chuah 
Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij

pinctrl: intel: Use raw_spinlock for locking

2016-06-18T08:35:44+00:00

When running -rt kernel and GPIO interrupt happens we get following

 BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:931
 in_atomic(): 1, irqs_disabled(): 0, pid: 530, name: irq/14-INT3452:
 Preemption disabled at:[] handle_edge_irq+0x1b/0x190

 CPU: 0 PID: 530 Comm: irq/14-INT3452: Not tainted 4.6.2-rt5 #1060
  0000000000000000 ffff88007a257d58 ffffffff812d8494 0000000000000000
  ffff88017a330000 ffff88007a257d78 ffffffff81083a11 ffff88007a252430
  ffff88007a252430 ffff88007a257d90 ffffffff8167ef20 000000000000001a
 Call Trace:
  [] dump_stack+0x4f/0x6b
  [] ___might_sleep+0xe1/0x160
  [] rt_spin_lock+0x20/0x50
  [] intel_gpio_irq_ack+0x2d/0x80
  [] handle_edge_irq+0x7b/0x190
  [] generic_handle_irq+0x22/0x30
  [] intel_gpio_irq+0xdc/0x150
  [] irq_forced_thread_fn+0x23/0x70
  [] irq_thread+0x13b/0x1d0
  [] ? __schedule+0x2e4/0x5a0
  [] ? irq_finalize_oneshot.part.37+0xd0/0xd0
  [] ? irq_thread+0x1d0/0x1d0
  [] ? wake_threads_waitq+0x30/0x30
  [] kthread+0xd4/0xf0
  [] ? _raw_spin_unlock_irq+0x17/0x40
  [] ret_from_fork+0x22/0x40
  [] ? kthread_worker_fn+0x190/0x190

The reason why this happens is because intel_gpio_irq_ack() is called with
desc->lock raw_spinlock locked which cannot sleep but our normal spinlock
(which is converted to rtmutex in -rt) is allowed to sleep. This causes
might_sleep() to trigger.

Fix this by converting the normal spinlock to a raw_spinlock.

Reported-by: Kim Tatt Chuah 
Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij

Merge tag 'pinctrl-v4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

2016-05-19T19:50:56+00:00

Pull pin control updates from Linus Walleij:
 "This kernel cycle was quite calm when it comes to pin control and
  there is really just one major change, and that is the introduction of
  devm_pinctrl_register() managed resources.

  Apart from that linear development, details below.

  Core changes:

   - Add the devm_pinctrl_register() API and switch all applicable
     drivers to use it, saving lots of lines of code all over the place.

  New drivers:

   - driver for the Broadcom NS2 SoC

   - subdriver for the PXA25x SoCs

   - subdriver for the AMLogic Meson GXBB SoC

  Driver improvements:

   - the Intel Baytrail driver now properly supports pin control

   - Nomadik, Rockchip, Broadcom BCM2835 support the .get_direction()
     callback in the GPIO portions

   - continued development and stabilization of several SH-PFC SoC
     subdrivers: r8a7795, r8a7790, r8a7794 etc"

* tag 'pinctrl-v4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (85 commits)
  Revert "pinctrl: tegra: avoid parked_reg and parked_bank"
  pinctrl: meson: Fix eth_tx_en bit index
  pinctrl: tegra: avoid parked_reg and parked_bank
  pinctrl: tegra: Correctly check the supported configuration
  pinctrl: amlogic: Add support for Amlogic Meson GXBB SoC
  pinctrl: rockchip: fix pull setting error for rk3399
  pinctrl: stm32: Implement .pin_config_dbg_show()
  pinctrl: nomadik: hide nmk_gpio_get_mode when unused
  pinctrl: ns2: rename pinctrl_utils_dt_free_map
  pinctrl: at91: Merge clk_prepare and clk_enable into clk_prepare_enable
  pinctrl: at91: Make at91_gpio_template const
  pinctrl: baytrail: fix some error handling in debugfs
  pinctrl: ns2: add pinmux driver support for Broadcom NS2 SoC
  pinctrl: sirf/atlas7: trivial fix of spelling mistake on flagged
  pinctrl: sh-pfc: Kill unused variable in sh_pfc_remove()
  pinctrl: nomadik: implement .get_direction()
  pinctrl: nomadik: use BIT() with offsets consequently
  pinctrl: exynos5440: Use off-stack memory for pinctrl_gpio_range
  pinctrl: zynq: Use devm_pinctrl_register() for pinctrl registration
  pinctrl: u300: Use devm_pinctrl_register() for pinctrl registration
  ...

pinctrl: intel: Use devm_pinctrl_register() for pinctrl registration

2016-04-20T22:02:28+00:00

Use devm_pinctrl_register() for pin control registration and clean
error path.

Signed-off-by: Laxman Dewangan 
Cc: Mika Westerberg 
Cc: Heikki Krogerus 
Signed-off-by: Linus Walleij

pinctrl: intel: implement gpio_irq_enable

2016-03-30T08:57:52+00:00

There is unexpected gpio interrupt after irq_enable. If not
implemeted gpio_irq_enable callback, irq_enable calls irq_unmask
instead. But if there was interrupt set before the irq_enable,
unmask it may trigger the unexpected interrupt. By implementing
the gpio_irq_enable callback, do interrupt status ack, the issue
has gone.

Signed-off-by: Qi Zheng 
Signed-off-by: Mika Westerberg 
Signed-off-by: Qipeng Zha 
Signed-off-by: Linus Walleij

pinctrl: intel: make the high level interrupt working

2016-03-30T08:57:52+00:00

High level trigger mode of GPIO interrupt is not set correctly
in intel_gpio_irq_type(), and will make this kind of interrupt
not respond.

Signed-off-by: Qi Zheng 
Signed-off-by: Qipeng Zha 
Acked-by: Mika Westerberg 
Signed-off-by: Linus Walleij

pinctrl: intel: Remove unneeded header includes

2016-02-12T12:56:57+00:00

pinctrl-intel doesn't use anything from ,
,  or , so it should not
include these header files.

Signed-off-by: Jean Delvare 
Cc: Heikki Krogerus 
Acked-by: Mika Westerberg 
Signed-off-by: Linus Walleij