linux-stable.git/drivers/pinctrl, branch v3.10.83

pinctrl: Don't just pretend to protect pinctrl_maps, do it for real

2015-05-17T16:51:33+00:00

commit c5272a28566b00cce79127ad382406e0a8650690 upstream.

Way back, when the world was a simpler place and there was no war, no
evil, and no kernel bugs, there was just a single pinctrl lock.  That
was how the world was when (57291ce pinctrl: core device tree mapping
table parsing support) was written.  In that case, there were
instances where the pinctrl mutex was already held when
pinctrl_register_map() was called, hence a "locked" parameter was
passed to the function to indicate that the mutex was already locked
(so we shouldn't lock it again).

A few years ago in (42fed7b pinctrl: move subsystem mutex to
pinctrl_dev struct), we switched to a separate pinctrl_maps_mutex.
...but (oops) we forgot to re-think about the whole "locked" parameter
for pinctrl_register_map().  Basically the "locked" parameter appears
to still refer to whether the bigger pinctrl_dev mutex is locked, but
we're using it to skip locks of our (now separate) pinctrl_maps_mutex.

That's kind of a bad thing(TM).  Probably nobody noticed because most
of the calls to pinctrl_register_map happen at boot time and we've got
synchronous device probing.  ...and even cases where we're
asynchronous don't end up actually hitting the race too often.  ...but
after banging my head against the wall for a bug that reproduced 1 out
of 1000 reboots and lots of looking through kgdb, I finally noticed
this.

Anyway, we can now safely remove the "locked" parameter and go back to
a war-free, evil-free, and kernel-bug-free world.

Fixes: 42fed7ba44e4 ("pinctrl: move subsystem mutex to pinctrl_dev struct")
Signed-off-by: Doug Anderson 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

pinctrl: Fix two deadlocks

2015-01-30T01:40:55+00:00

commit db93facfb0ef542aa5d8079e47580b3e669a4d82 upstream.

This patch is to fix two deadlock cases.
Deadlock 1:
CPU #1
 pinctrl_register-> pinctrl_get ->
 create_pinctrl
 (Holding lock pinctrl_maps_mutex)
 -> get_pinctrl_dev_from_devname
 (Trying to acquire lock pinctrldev_list_mutex)
CPU #0
 pinctrl_unregister
 (Holding lock pinctrldev_list_mutex)
 -> pinctrl_put ->> pinctrl_free ->
 pinctrl_dt_free_maps -> pinctrl_unregister_map
 (Trying to acquire lock pinctrl_maps_mutex)

Simply to say
CPU#1 is holding lock A and trying to acquire lock B,
CPU#0 is holding lock B and trying to acquire lock A.

Deadlock 2:
CPU #3
 pinctrl_register-> pinctrl_get ->
 create_pinctrl
 (Holding lock pinctrl_maps_mutex)
 -> get_pinctrl_dev_from_devname
 (Trying to acquire lock pinctrldev_list_mutex)
CPU #2
 pinctrl_unregister
 (Holding lock pctldev->mutex)
 -> pinctrl_put ->> pinctrl_free ->
 pinctrl_dt_free_maps -> pinctrl_unregister_map
 (Trying to acquire lock pinctrl_maps_mutex)
CPU #0
 tegra_gpio_request
 (Holding lock pinctrldev_list_mutex)
 -> pinctrl_get_device_gpio_range
 (Trying to acquire lock pctldev->mutex)

Simply to say
CPU#3 is holding lock A and trying to acquire lock D,
CPU#2 is holding lock B and trying to acquire lock A,
CPU#0 is holding lock D and trying to acquire lock B.

Signed-off-by: Jim Lin 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

pinctrl: protect pinctrl_list add

2014-02-20T19:06:11+00:00

commit 7b320cb1ed2dbd2c5f2a778197baf76fd6bf545a upstream.

We have few fedora bug reports about list corruption on pinctrl,
for example:
https://bugzilla.redhat.com/show_bug.cgi?id=1051918

Most likely corruption happen due lack of protection of pinctrl_list
when adding new nodes to it. Patch corrects that.

Fixes: 42fed7ba44e ("pinctrl: move subsystem mutex to pinctrl_dev struct")
Signed-off-by: Stanislaw Gruszka 
Acked-by: Stephen Warren 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

pinctrl: vt8500: Change devicetree data parsing

2014-02-20T19:06:11+00:00

commit f17248ed868767567298e1cdf06faf8159a81f7c upstream.

Due to an assumption in the VT8500 pinctrl driver, the value passed
from devicetree for 'wm,pull' was not explicitly translated before
being passed to pinconf.

Since v3.10, changes to 'enum pin_config_param', PIN_CONFIG_BIAS_PULL_(UP/DOWN)
no longer map 1-to-1 with the expected values in devicetree.

This patch adds a small translation between the devicetree values (0..2)
and the enum pin_config_param equivalent values.

Signed-off-by: Tony Prisk 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

pinctrl: sunxi: Honor GPIO output initial vaules

2014-02-06T19:08:15+00:00

commit fa8cf57c923e86a693a85aff1df579245a27cbb3 upstream.

Some GPIO users, such as fixed-regulator, request GPIO output with
initial value of 1. This was ignored by sunxi driver.

Signed-off-by: Chen-Yu Tsai 
Acked-by: Maxime Ripard 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

pinctrl: dove: unset twsi option3 for gconfig as well

2013-12-04T18:55:49+00:00

commit 6d0a4ed2b90a12e1403d3e7d9d8c2cc7fdc301b5 upstream.

This fixes a typo which left twsi config3 option enabled.

Signed-off-by: Roel Kluin 
Acked-by: Sebastian Hesselbarth 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

pinctrl: at91: fix get_pullup/down function return

2013-09-27T00:18:14+00:00

commit 05d3534a321d7fe4524b3b83bb20318282f3ec2c upstream.

In PIO_PUSR and PIO_PPDSR register if a given bit is set 1 this means the
pullup/down for this pin (pin is represented as a bit position) is
disabled.

Signed-off-by: Boris BREZILLON 
Acked-by: Nicolas Ferre 
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'renesas-fixes-for-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into fixes

2013-06-08T01:11:02+00:00

From Simon Horman, Renesas ARM based SoC fixes for v3.10:
- Correction to USB OVC and PENC pin groupings on r8a7779 SoC.
  This avoids conflicts when the USB_OVCn pins are used by another function.
  This has been observed to be a problem in v3.10-rc1.
- Update CMT clock rating for sh73a0 SoC to resolve boot failure
  on kzm9g-reference. This resolves a regression between v3.9 and v3.10-rc1.

* tag 'renesas-fixes-for-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
  ARM: shmobile: sh73a0: Update CMT clockevent rating to 80
  sh-pfc: r8a7779: Don't group USB OVC and PENC pins

Signed-off-by: Olof Johansson

sh-pfc: r8a7779: Don't group USB OVC and PENC pins

2013-06-04T05:37:43+00:00

The USB_OVCn pins are alternate options for USB over-current detection
when using a 3.3V USB interface. As they're not mandatory they can be
used independently of the USB PENC pins. Don't group the USB_OVCn and
PENC pins to avoid conflicts when the USB_OVCn pins are used by another
function.

Reported-by: Sergei Shtylyov 
Signed-off-by: Laurent Pinchart 
Acked-by: Linus Walleij 
Signed-off-by: Simon Horman

pinctrl: pinconf: take the right mutex

2013-05-27T13:53:32+00:00

The pinconf_dgb_config_print() takes the per-pincontroller
mutex, when what it wants to take is actually the pin maps
mutex.

Reported-by: James Hogan 
Cc: Patrice Chotard 
Signed-off-by: Linus Walleij