linux-toradex.git/drivers/pinctrl/pinctrl-u300.c, branch v4.4.73

pinctrl: make pinctrl_register() return proper error code

2015-06-10T12:49:52+00:00

Currently, pinctrl_register() just returns NULL on error, so the
callers can not know the exact reason of the failure.

Some of the pinctrl drivers return -EINVAL, some -ENODEV, and some
-ENOMEM on error of pinctrl_register(), although the error code
might be different from the real cause of the error.

This commit reworks pinctrl_register() to return the appropriate
error code and modifies all of the pinctrl drivers to use IS_ERR()
for the error checking and PTR_ERR() for getting the error code.

Signed-off-by: Masahiro Yamada 
Acked-by: Patrice Chotard 
Acked-by: Thierry Reding 
Acked-by: Heiko Stuebner 
Tested-by: Mika Westerberg 
Acked-by: Mika Westerberg 
Acked-by: Lee Jones 
Acked-by: Sören Brinkmann 
Acked-by: Laurent Pinchart 
Acked-by: Ray Jui 
Acked-by: Antoine Tenart 
Acked-by: Hongzhou Yang 
Acked-by: Wei Chen 
Signed-off-by: Linus Walleij

pinctrl: drop owner assignment from platform_drivers

2014-10-20T14:21:21+00:00

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang

pinctrl: clean up after enable refactoring

2014-09-04T08:05:07+00:00

commit 2243a87d90b42eb38bc281957df3e57c712b5e56
"pinctrl: avoid duplicated calling enable_pinmux_setting for a pin"
removed the .disable callback from the struct pinmux_ops,
making the .enable() callback the only remaining callback.

However .enable() is a bad name as it seems to imply that a
muxing can also be disabled. Rename the callback to .set_mux()
and also take this opportunity to clean out any remaining
mentions of .disable() from the documentation.

Acked-by: Stephen Warren 
Acked-by: Bjorn Andersson 
Acked-by: Fan Wu 
Signed-off-by: Linus Walleij

pinctrl: avoid duplicated calling enable_pinmux_setting for a pin

2014-07-11T12:08:26+00:00

What the patch does:
1. Call pinmux_disable_setting ahead of pinmux_enable_setting
  each time pinctrl_select_state is called
2. Remove the HW disable operation in pinmux_disable_setting function.
3. Remove the disable ops in struct pinmux_ops
4. Remove all the disable ops users in current code base.

Notes:
1. Great thanks for the suggestion from Linus, Tony Lindgren and
   Stephen Warren and Everyone that shared comments on this patch.
2. The patch also includes comment fixes from Stephen Warren.

The reason why we do this:
1. To avoid duplicated calling of the enable_setting operation
   without disabling operation inbetween which will let the pin
   descriptor desc->mux_usecount increase monotonously.
2. The HW pin disable operation is not useful for any of the
   existing platforms.
   And this can be used to avoid the HW glitch after using the
   item #1 modification.

In the following case, the issue can be reproduced:
1. There is a driver that need to switch pin state dynamically,
   e.g. between "sleep" and "default" state
2. The pin setting configuration in a DTS node may be like this:

  component a {
	pinctrl-names = "default", "sleep";
	pinctrl-0 = <&a_grp_setting &c_grp_setting>;
	pinctrl-1 = <&b_grp_setting &c_grp_setting>;
  }

  The "c_grp_setting" config node is totally identical, maybe like
  following one:

  c_grp_setting: c_grp_setting {
	pinctrl-single,pins = ;
  }

3. When switching the pin state in the following official pinctrl
   sequence:
	pin = pinctrl_get();
	state = pinctrl_lookup_state(wanted_state);
	pinctrl_select_state(state);
	pinctrl_put();

Test Result:
1. The switch is completed as expected, that is: the device's
   pin configuration is changed according to the description in the
   "wanted_state" group setting
2. The "desc->mux_usecount" of the corresponding pins in "c_group"
   is increased without being decreased, because the "desc" is for
   each physical pin while the setting is for each setting node
   in the DTS.
   Thus, if the "c_grp_setting" in pinctrl-0 is not disabled ahead
   of enabling "c_grp_setting" in pinctrl-1, the desc->mux_usecount
   will keep increasing without any chance to be decreased.

According to the comments in the original code, only the setting,
in old state but not in new state, will be "disabled" (calling
pinmux_disable_setting), which is correct logic but not intact. We
still need consider case that the setting is in both old state
and new state. We can do this in the following two ways:

1. Avoid to "enable"(calling pinmux_enable_setting) the "same pin
   setting" repeatedly
2. "Disable"(calling pinmux_disable_setting) the "same pin setting",
   actually two setting instances, ahead of enabling them.

Analysis:
1. The solution #2 is better because it can avoid too much
   iteration.
2. If we disable all of the settings in the old state and one of
   the setting(s) exist in the new state, the pins mux function
   change may happen when some SoC vendors defined the
   "pinctrl-single,function-off"
   in their DTS file.
   old_setting => disabled_setting => new_setting.
3. In the pinmux framework, when a pin state is switched, the
   setting in the old state should be marked as "disabled".

Conclusion:
1. To Remove the HW disabling operation to above the glitch mentioned
   above.
2. Handle the issue mentioned above by disabling all of the settings
   in old state and then enable the all of the settings in new state.

Signed-off-by: Fan Wu 
Acked-by: Stephen Warren 
Acked-by: Patrice Chotard 
Acked-by: Heiko Stuebner 
Acked-by: Maxime Coquelin 
Signed-off-by: Linus Walleij

pinctrl: Pass all configs to driver on pin_config_set()

2013-08-28T11:34:41+00:00

When setting pin configuration in the pinctrl framework, pin_config_set() or
pin_config_group_set() is called in a loop to set one configuration at a time
for the specified pin or group.

This patch 1) removes the loop and 2) changes the API to pass the whole pin
config array to the driver.  It is now up to the driver to loop through the
configs.  This allows the driver to potentially combine configs and reduce the
number of writes to pin config registers.

All c files changed have been build-tested to verify the change compiles and
that the corresponding .o is successfully generated.

Signed-off-by: Sherman Yin 
Reviewed-by: Christian Daudt 
Reviewed-by: Matt Porter 
Tested-by: Stephen Warren 
Acked-by: Laurent Pinchart 
Signed-off-by: Linus Walleij

drivers/pinctrl: don't check resource with devm_ioremap_resource

2013-08-07T20:29:21+00:00

devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.

Signed-off-by: Wolfram Sang 
Signed-off-by: Linus Walleij

Merge tag 'pinctrl-for-v3.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

2013-07-03T18:48:03+00:00

Pull pin control changes from Linus Walleij:

- A large slew of improvements of the Genric pin configuration support,
and deployment in four different platforms: Rockchip, Super-H PFC,
ABx500 and TZ1090. Support BIAS_BUS_HOLD, get device tree parsing
and debugfs support into shape.

- We also have device tree support with generic naming conventions for
the generic pin configuration.

- Delete the unused and confusing direct pinconf API. Now state
transitions is *the* way to control pins and multiplexing.

- New drivers for Rockchip, TZ1090, and TZ1090 PDC.

- Two pin control states related to power management are now handled in
the device core: "sleep" and "idle", removing a lot of boilerplate
code in drivers. We do not yet know if this is the final word for
pin PM, but it already make things a lot easier to handle.

- Handle sparse GPIO ranges passing a list of disparate pins, and
utilize these in the new BayTrail (x86 Atom SoC) driver.

- Make the sunxi (AllWinner) driver handle external interrupts.

- Make it possible for pinctrl-single to handle the case where several
pins are managed by a single register, and augment it to handle sleep
modes.

- Cleanups and improvements for the abx500 drivers.

- Move Sirf pin control drivers to their own directory, support
save/restore of context and add support for the SiRFatlas6 SoC.

- PMU muxing for the Dove pinctrl driver.

- Finalization and support for VF610 in the i.MX6 pinctrl driver.

- Smoothen out various Exynos rough edges.

- Generic cleanups of various kinds.

* tag 'pinctrl-for-v3.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (82 commits)
pinctrl: vt8500: wmt: remove redundant dev_err call in wmt_pinctrl_probe()
pinctrl: remove bindings for pinconf options needing more thought
pinctrl: remove slew-rate parameter from tz1090
pinctrl: set unit for debounce time pinconfig to usec
pinctrl: more clarifications for generic pull configs
pinctrl: rip out the direct pinconf API
pinctrl-tz1090-pdc: add TZ1090 PDC pinctrl driver
pinctrl-tz1090: add TZ1090 pinctrl driver
pinctrl: samsung: Staticize drvdata_list
pinctrl: rockchip: Add missing irq_gc_unlock() call before return error
pinctrl: abx500: rework error path
pinctrl: abx500: suppress hardcoded value
pinctrl: abx500: factorize code
pinctrl: abx500: fix abx500_gpio_get()
pinctrl: abx500: fix abx500_pin_config_set()
pinctrl: abx500: Add device tree support
sh-pfc: Guard DT parsing with #ifdef CONFIG_OF
pinctrl: add Intel BayTrail GPIO/pinctrl support
pinctrl: fix pinconf_ops::pin_config_dbg_parse_modify kerneldoc
pinctrl: Staticize local symbols
...

Conflicts:
drivers/net/ethernet/ti/davinci_mdio.c
drivers/pinctrl/Makefile

pinctrl: u300: remove unnecessary platform_set_drvdata()

2013-06-16T09:56:48+00:00

The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d0631001288a5974afc0b2a5f568bcdecb4d
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han 
Signed-off-by: Linus Walleij

pinctrl: u300 device tree support

2013-05-31T09:24:50+00:00

This adds a simple device tree compat string for the U300 pin
controller. The base address is already passed properly as
a resource and everything works fine.

Signed-off-by: Linus Walleij

pinctrl: Declare operation structures as const

2013-03-07T04:27:29+00:00

The pinconf, pinctrl and pinmux operation structures hold function
pointers that are never modified. Declare them as const.

Signed-off-by: Laurent Pinchart 
Signed-off-by: Linus Walleij