linux-stable.git/drivers/pinctrl, branch linux-3.16.y

pinctrl: baytrail: Really serialize all register accesses

2020-04-28T18:02:41+00:00

commit 40ecab551232972a39cdd8b6f17ede54a3fdb296 upstream.

Commit 39ce8150a079 ("pinctrl: baytrail: Serialize all register access")
added a spinlock around all register accesses because:

"There is a hardware issue in Intel Baytrail where concurrent GPIO register
 access might result reads of 0xffffffff and writes might get dropped
 completely."

Testing has shown that this does not catch all cases, there are still
2 problems remaining

1) The original fix uses a spinlock per byt_gpio device / struct,
additional testing has shown that this is not sufficient concurent
accesses to 2 different GPIO banks also suffer from the same problem.

This commit fixes this by moving to a single global lock.

2) The original fix did not add a lock around the register accesses in
the suspend/resume handling.

Since pinctrl-baytrail.c is using normal suspend/resume handlers,
interrupts are still enabled during suspend/resume handling. Nothing
should be using the GPIOs when they are being taken down, _but_ the
GPIOs themselves may still cause interrupts, which are likely to
use (read) the triggering GPIO. So we need to protect against
concurrent GPIO register accesses in the suspend/resume handlers too.

This commit fixes this by adding the missing spin_lock / unlock calls.

The 2 fixes together fix the Acer Switch 10 SW5-012 getting completely
confused after a suspend resume. The DSDT for this device has a bug
in its _LID method which reprograms the home and power button trigger-
flags requesting both high and low _level_ interrupts so the IRQs for
these 2 GPIOs continuously fire. This combined with the saving of
registers during suspend, triggers concurrent GPIO register accesses
resulting in saving 0xffffffff as pconf0 value during suspend and then
when restoring this on resume the pinmux settings get all messed up,
resulting in various I2C busses being stuck, the wifi no longer working
and often the tablet simply not coming out of suspend at all.

Fixes: 39ce8150a079 ("pinctrl: baytrail: Serialize all register access")
Signed-off-by: Hans de Goede 
Acked-by: Mika Westerberg 
Signed-off-by: Andy Shevchenko 
[bwh: Backported to 3.16:
 - Drop changes in functions that don't exist here
 - Delete local pointers to byt_gpio that become unused
 - Adjust filename, context]
Signed-off-by: Ben Hutchings

pinctrl: baytrail: Serialize all register access

2020-04-28T18:02:41+00:00

commit 39ce8150a079e3ae6ed9abf26d7918a558ef7c19 upstream.

There is a hardware issue in Intel Baytrail where concurrent GPIO register
access might result reads of 0xffffffff and writes might get dropped
completely.

Prevent this from happening by taking the serializing lock in all places
where it is possible that more than one thread might be accessing the
hardware concurrently.

Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij 
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings

pinctrl: baytrail: Rework interrupt handling

2020-04-28T18:02:40+00:00

commit 31e4329f99062a06dca5a493bb4495a63b2dc6ba upstream.

Instead of handling everything in the driver's first level interrupt
handler, we can take advantage of already existing flow handlers that are
provided by the IRQ core.

This changes the functionality a bit also. Previously the driver looped
over pending interrupts in a single loop, restarting the loop if some
interrupt changed state. This caused problem with Lenovo Thinkpad 10
digitizer that it was not able to deassert the interrupt before the driver
disabled the interrupt for good (looplimit was exhausted).

Rework the interrupt handling logic a bit so that we provide proper mask,
ack and unmask operations in terms of Baytrail GPIO hardware and loop over
pending interrupts only once. If the interrupt remains asserted the first
level handler will be re-triggered automatically.

Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij 
[bwh: Backported to 3.16 as dependency of commit 39ce8150a079
 "pinctrl: baytrail: Serialize all register access":
 - Adjust filename, context]
Signed-off-by: Ben Hutchings

pinctrl: baytrail: Clear interrupt triggering from pins that are in GPIO mode

2020-04-28T18:02:40+00:00

commit 95f0972c7e4cbf3fc68160131c5ac2f033481d00 upstream.

If the pin is already configured as GPIO and it has any of the triggering
flags set, we may get spurious interrupts depending on the state of the
pin.

Prevent this by clearing the triggering flags on such pins. However, if the
pin is also configured as "direct IRQ" we leave the flags as is. Otherwise
it will prevent interrupts that are routed directly to IO-APIC.

Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij 
[bwh: Backported to 3.16:
 - Add definition of BYT_DIRECT_IRQ_EN
 - Adjust filename]
Signed-off-by: Ben Hutchings

pinctrl: baytrail: Relax GPIO request rules

2020-04-28T18:02:40+00:00

commit f8323b6bb2cc7d26941d4838dd4375952980a88a upstream.

Zotac ZBOX PI320, a Baytrail based mini-PC, has power button connected to a
GPIO pin and it is exposed to the operating system as Windows 8 button
array. This is implemented in Linux as a driver using gpio_keys.

However, BIOS on this particula machine forgot to mux the pin to be a GPIO
instead of native function, which results following message to be seen on
the console:

 byt_gpio INT33FC:02: pin 16 cannot be used as GPIO.

This causes power button to not work as the driver was not able to request
the GPIO it needs.

So instead of completely preventing this we allow turning the pin as GPIO
but issue warning that something might be wrong.

Reported-by: Benjamin Adler 
Signed-off-by: Mika Westerberg 
Signed-off-by: Linus Walleij 
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings

pinctrl: samsung: Fix device node refcount leaks in S3C64xx wakeup controller init

2020-02-11T20:03:12+00:00

commit 7f028caadf6c37580d0f59c6c094ed09afc04062 upstream.

In s3c64xx_eint_eint0_init() the for_each_child_of_node() loop is used
with a break to find a matching child node.  Although each iteration of
for_each_child_of_node puts the previous node, but early exit from loop
misses it.  This leads to leak of device node.

Fixes: 61dd72613177 ("pinctrl: Add pinctrl-s3c64xx driver")
Signed-off-by: Krzysztof Kozlowski 
[bwh: Backported to 3.16: adjust filename, context]
Signed-off-by: Ben Hutchings

pinctrl: samsung: Fix device node refcount leaks in S3C24xx wakeup controller init

2020-02-11T20:03:12+00:00

commit 6fbbcb050802d6ea109f387e961b1dbcc3a80c96 upstream.

In s3c24xx_eint_init() the for_each_child_of_node() loop is used with a
break to find a matching child node.  Although each iteration of
for_each_child_of_node puts the previous node, but early exit from loop
misses it.  This leads to leak of device node.

Fixes: af99a7507469 ("pinctrl: Add pinctrl-s3c24xx driver")
Signed-off-by: Krzysztof Kozlowski 
[bwh: Backported to 3.16: adjust filename, context]
Signed-off-by: Ben Hutchings

pinctrl: sh-pfc: sh73a0: Fix fsic_spdif pin groups

2019-07-09T21:03:59+00:00

commit 0e6e448bdcf896d001a289a6112a704542d51516 upstream.

There are two pin groups for the FSIC SPDIF signal, but the FSIC pin
group array lists only one, and it refers to a nonexistent group.

Fixes: 2ecd4154c906b7d6 ("sh-pfc: sh73a0: Add FSI pin groups and functions")
Signed-off-by: Geert Uytterhoeven 
Reviewed-by: Simon Horman 
Signed-off-by: Ben Hutchings

pinctrl: sh-pfc: r8a7791: Fix scifb2_data_c pin group

2019-07-09T21:03:59+00:00

commit a4b0350047f1b10207e25e72d7cd3f7826e93769 upstream.

The entry for "scifb2_data_c" in the SCIFB2 pin group array contains a
typo, thus the group cannot be selected.

Fixes: 5088451962389924 ("pinctrl: sh-pfc: r8a7791 PFC support")
Signed-off-by: Geert Uytterhoeven 
Reviewed-by: Simon Horman 
Signed-off-by: Ben Hutchings

pinctrl: sh-pfc: r8a7778: Fix HSPI pin numbers and names

2019-07-09T21:03:49+00:00

commit 8e32e881947be98abaa917157fefc4a3319e90af upstream.

When declaring the HSPI RX1_B and TX1_B pins, two mistakes were made:
  - the rows and columns in the BGA pin matrix, from which the pin
    numbers are derived, were exchanged,
  - it was not taken into account that pin row labelling skips
    characters I, O, Q, and S.

Fix the order, and the corresponding pin names.

Notes:
  - The actual values of the pin numbers don't really matter (they just
    have to be unique), so the wrong order didn't have any impact,
  - Changing the names of the pins is user-visible, but there are no
    users in (upstream) DTS files.

Fixes: 4f82e3ee724f1712 ("sh-pfc: Support pins not associated with a GPIO port")
Fixes: 09cc76a95802e87d ("sh-pfc: r8a7778: add HSPI pin groups")
Signed-off-by: Geert Uytterhoeven 
Reviewed-by: Simon Horman 
Signed-off-by: Ben Hutchings