Multiple mapping table entries could reference the same pin, and hence
"own" it. This would be unusual now that pinctrl_get() represents a single
state for a client device, but in the future when it represents all known
states for a device, this is quite likely. Implement reference counting
for pin ownership to handle this.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This change separates two aspects of struct pinctrl:

a) The data representation of the parsed mapping table, into:

   1) The top-level struct pinctrl object, a single entity returned
      by pinctrl_get().

   2) The parsed version of each mapping table entry, struct
      pinctrl_setting, of which there is one per mapping table entry.

b) The code that handles this; the code for (1) above is in core.c, and
   the code to parse/execute each entry in (2) above is in pinmux.c, while
   the iteration over multiple settings is lifted to core.c.

This will allow the following future changes:

1) pinctrl_get() API rework, so that struct pinctrl represents all states
   for the device, and the device can select between them without calling
   put()/get() again.

2) To support that, a struct pinctrl_state object will be inserted into
   the data model between the struct pinctrl and struct pinctrl_setting.

3) The mapping table will be extended to allow specification of pin config
   settings too. To support this, struct pinctrl_setting will be enhanced
   to store either mux settings or config settings, and functions will be
   added to pinconf.c to parse/execute pin configuration settings.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

There are many problems with the current pinctrl locking:

struct pinctrl_dev's gpio_ranges_lock isn't effective;
pinctrl_match_gpio_range() only holds this lock while searching for a gpio
range, but the found range is return and manipulated after releading the
lock. This could allow pinctrl_remove_gpio_range() for that range while it
is in use, and the caller may very well delete the range after removing it,
causing pinctrl code to touch the now-free range object.

Solving this requires the introduction of a higher-level lock, at least
a lock per pin controller, which both gpio range registration and
pinctrl_get()/put() will acquire.

There is missing locking on HW programming; pin controllers may pack the
configuration for different pins/groups/config options/... into one
register, and hence have to read-modify-write the register. This needs to
be protected, but currently isn't. Related, a future change will add a
"complete" op to the pin controller drivers, the idea being that each
state's programming will be programmed into the pinctrl driver followed
by the "complete" call, which may e.g. flush a register cache to HW. For
this to work, it must not be possible to interleave the pinctrl driver
calls for different devices.

As above, solving this requires the introduction of a higher-level lock,
at least a lock per pin controller, which will be held for the duration
of any pinctrl_enable()/disable() call.

However, each pinctrl mapping table entry may affect a different pin
controller if necessary. Hence, with a per-pin-controller lock, almost
any pinctrl API may need to acquire multiple locks, one per controller.
To avoid deadlock, these would need to be acquired in the same order in
all cases. This is extremely difficult to implement in the case of
pinctrl_get(), which doesn't know which pin controllers to lock until it
has parsed the entire mapping table, since it contains somewhat arbitrary
data.

The simplest solution here is to introduce a single lock that covers all
pin controllers at once. This will be acquired by all pinctrl APIs.

This then makes struct pinctrl's mutex irrelevant, since that single lock
will always be held whenever this mutex is currently held.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The introduction of the owner field on the pin descriptor was not
properly documented so fix this up.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinctrl_register_mappings() already requires that every mapping table
entry have a non-NULL name field.

Logically, this makes sense too; drivers should always request a specific
named state so they know what they're getting. Relying on getting the
first mentioned state in the mapping table is error-prone, and a nasty
special case to implement, given that a given the mapping table may define
multiple states for a device.

Remove a small part of the documentation that talked about optionally
requesting a specific state; it's mandatory now.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This provides a single centralized name for the default state.

Update PIN_MAP_* macros to use this state name, instead of requiring the
user to pass a state name in.

With this change, hog entries in the mapping table are defined as those
with state name PINCTRL_STATE_DEFAULT, i.e. all entries have the same
name. This interacts badly with the nested iteration over mapping table
entries in pinctrl_hog_maps() and pinctrl_hog_map() which would now
attempt to claim each hog mapping table entry multiple times. Replacing
the custom hog code with a simple pinctrl_get()/pinctrl_enable().

Update documentation and mapping tables to use this.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

At present, pinctrl_get() assumes that all matching mapping table entries
have the same "function" value, albeit potentially applied to different
pins/groups.

This change removes this restriction; pinctrl_get() can now handle a set
of mapping tables where different functions are applied to the various
pins/groups.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The debugfs file pinctrl-maps is a system-wide file, not specific to any
pin controller, so place it in the top-level directory.

Also, move the code implementing the file to keep the order of all the
functions matching the order they're created in pinctrl_init_*debugfs().
The only non-obvious change here is no private data is passed to
debugfs_create_file() or single_open().
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The lookup key in struct pinctrl_map is (.dev_name, .name). Re-order the
struct definition to put the lookup key fields first, and the result
values afterwards. To me at least, this slightly better reflects the
lookup process.

Update the documentation in a similar fashion.

Note: PIN_MAP*() macros aren't updated; I plan to update this once later
when enhancing the mapping table format to support pin config to reduce
churn.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
[Rebased for cherry-picking]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The debugfs file pinmux-pins used to tell which function was
enabled but now states simply which device owns the pin. Being
owned by the pinctrl driver itself means just that it's hogged
so be a bit more helpful by printing that.

ChangeLog v1->v2:
- Preserve the self-referential owner field, just clarify that
  when the pin controller states itself as owner this means
  that it's hogged.
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

struct pinctrl_dev's pin_desc_tree_lock and pinctrl_hogs_lock aren't
useful; the data they protect is read-only except when registering or
unregistering a pinctrl_dev, and at those times, it doesn't make sense to
protect one part of the structure independently from the rest.

Move pinctrl_init_device_debugfs() to the end of pinctrl_register() so
that debugfs can't access the struct pinctrl_dev until it's fully
initialized, i.e. after the hogs are set up.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This hopefully makes it harder to take the sizeof the wrong type.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

e.g. dev_err instead of pr_err prints messages in a slightly more
standardized format.

Also, add a few more error messages to track down errors.

Also, some small cleanups of messages.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Hog entries are mapping table entries with .ctrl_dev_name == .dev_name.
All other mapping table entries need .dev_name set so that they will
match some pinctrl_get() call. All extant PIN_MAP*() macros set
.dev_name.

So, there is no reason to allow mapping table entries without .dev_name
set. Update the code and documentation to disallow this.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

pinconf_groups_show() wrote all debug information on one line. Fix it to
match pinconf_pins_show() and be legible.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

When pins are requested/acquired/got, some device becomes the owner of
their mux setting. At this point, it isn't certain which mux function
will be selected for the pin, since this may vary between each of the
device's states in the pinctrl mapping table. As such, we should record
the owning device, not what we think the initial mux setting will be,
when requesting pins.

This doesn't make a lot of difference right now since pinctrl_get gets
only one single device/state combination, but this will make a difference
when pinctrl_get gets all states, and pinctrl_select_state can switch
between states.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This is a serious error, and the pin control system will not function
correctly if it ends up not programing the mapping table entries into
the HW. Instead of just ignoring this, error out.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
[rebased to fit the applied patch series, cast error to pointer]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This may be perfectly legitimate. An IP block may get re-used
across SoCs. Not all of those SoCs may need pinmux settings for the
IP block, e.g. if one SoC dedicates pins to that function but
another doesn't. The driver won't know this, and will always
attempt to set up the pinmux. The mapping table defines whether any
HW programming is actually needed.
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
[rebased to fit the applied patch series]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

These are already disallowed. Clean up some code that doesn't assume this.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This solves the riddle on how the U300 pin controller shall be
able to reference the struct gpio_chip even though these are
two separate drivers: spawn the pinctrl child from the GPIO
driver and pass in the struct gpio_chip as platform data.
In the process we rename the U300 "pinmux-u300" to
"pinctrl-u300" so as not to confuse.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

* Make all functions internal to core.c static. Remove any of these from
  core.h.
* Add any missing EXPORT_SYMBOL_GPL().
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Modify the two files so that the order of function prototypes in the
header matches the order of implementations in the .c file.

Don't prototype a couple of internal functions.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Modify the two files so that the order of function prototypes in the
header matches the order of implementations in the .c file.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Instead of storing a single array of mapping table entries, which
requires realloc()ing that array each time it's extended and copying
the new data, simply store a list of pointers to the individual chunks.
This also removes the need to copy the mapping table at all; a pointer
is maintained to the original table, this saving memory.

A macro for_each_maps() is introduced to hide the additional complexity
of iterating over the map entries.

This change will also simplify removing chunks of entries from the mapping
table. This isn't important right now, but will be in the future, when
mapping table entries are dynamically added when parsing them from the
device tree, and removed when drivers no longer need to interact with
pinctrl.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This mostly makes debugfs files print things in the order that they
were added or acquired, which just feels a little more consistent.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

It may be common for pinctrl_register_mappings() to be used from __init
context, but there's no reason that additional mappings shouldn't be
added at a later point, e.g. if loading modules that add pin controllers
and their mapping tables.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Commit 77a59883 "pinctrl: changes hog mechanism to be self-referential"
modified the way "hog" entries were represented in the mapping table.
However, the new representation failed some error checks in
pinctrl_hog_map(). Remove the now-bogus error-check, and fix the code
to solve the issue the error-check used to avoid.
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

We changed the signature of the pin multiplexing functions to
handle any pin business, so fix up the Sirf driver to call this
new interface and rename some variables to make the semantics
understandable.

Cc: linux-serial@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Instead of a specific boolean field to indicate if a map entry shall
be hogged, treat self-reference as an indication of desired hogging.
This drops one field off the map struct and has a nice Douglas R.
Hofstadter-feel to it.
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This moves the per-devices struct pinctrl handles and device map
over from the pinmux part of the subsystem to the core pinctrl part.
This makes the device handles core infrastructure with the goal of
using these handles also for pin configuration, so that device
drivers (or boards etc) will need one and only one handle to the
pin control core.
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Since we want to use the former pinmux handles and mapping tables for
generic control involving both muxing and configuration we begin
refactoring by renaming them from pinmux_* to pinctrl_*.

ChangeLog v1->v2:
- Also rename the PINMUX_* macros in machine.h to PIN_ as indicated
  in the documentation so as to reflect the generic nature of these
  mapping entries from now on.
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This breaks out a <linux/pinctrl/consumer.h> header to be used by
all pinmux and pinconfig alike, so drivers needing services from
pinctrl does not need to include different headers. This is similar
to the approach taken by the regulator API.
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Support PXA168/PXA910/MMP2 pinmux. Now only support function switch.
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
[Rebase and fix some whitespace issues]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

After discussion with Mark Brown in an unrelated thread about
ADC lookups, it came to my knowledge that the ability to pass
a struct device * in the regulator consumers is just a
historical artifact, and not really recommended. Since there
are no in-kernel users of these pointers, we just kill them
right now, before someone starts to use them.
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Commit ca53c5f1
("pinctrl: conjure names for unnamed pins") made pins lose
their identity and only get autogenerated names.
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

There are few important bug fixes for LogFS

* tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream:
  Logfs: Allow NULL block_isbad() methods
  logfs: Grow inode in delete path
  logfs: Free areas before calling generic_shutdown_super()
  logfs: remove useless BUG_ON
  MAINTAINERS: Add Prasad Joshi in LogFS maintiners
  logfs: Propagate page parameter to __logfs_write_inode
  logfs: set superblock shutdown flag after generic sb shutdown
  logfs: take write mutex lock during fsync and sync
  logfs: Prevent memory corruption
  logfs: update page reference count for pined pages

Fix up conflict in fs/logfs/dev_mtd.c due to semantic change in what
"mtd->block_isbad" means in commit f2933e86: "Logfs: Allow NULL
block_isbad() methods" clashing with the abstraction changes in the
commits 7086c19d: "mtd: introduce mtd_block_isbad interface" and
d58b27ed: "logfs: do not use 'mtd->block_isbad' directly".

This resolution takes the semantics from commit f2933e86, and just
makes mtd_block_isbad() return zero (false) if the 'block_isbad'
function is NULL.  But that also means that now "mtd_can_have_bb()"
always returns 0.

Now, "mtd_block_markbad()" will obviously return an error if the
low-level driver doesn't support bad blocks, so this is somewhat
non-symmetric, but it actually makes sense if a NULL "block_isbad"
function is considered to mean "I assume that all my blocks are always
good".

Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (w83627ehf) Disable setting DC mode for pwm2, pwm3 on NCT6776F
  hwmon: (sht15) fix bad error code
  MAINTAINERS: Drop maintainer for MAX1668 hwmon driver
  MAINTAINERS: Add hwmon entries for Wolfson
  hwmon: (f71805f) Fix clamping of temperature limits

Here are some fixes to the pin control system that has accumulated since
-rc1.  Mainly Tony Lindgren fixed the module load/unload logic and the
rest are minor fixes and documentation.

* 'for-torvalds' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: add checks for empty function names
  pinctrl: fix pinmux_hog_maps when ctrl_dev_name is not set
  pinctrl: fix some pinmux typos
  pinctrl: free debugfs entries when unloading a pinmux driver
  pinctrl: unbreak error messages
  Documentation/pinctrl: fix a few syntax errors in code examples
  pinctrl: fix pinconf_pins_show iteration

Here are some tty/serial patches for 3.3-rc1

Big thing here is the movement of the 8250 serial drivers to their own
directory, now that the patch churn has calmed down.

Other than that, only minor stuff (omap patches were reverted as they
were found to be wrong), and another broken driver removed from the
system.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

* tag 'tty-3.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: Kill off Moorestown code
  Revert "tty: serial: OMAP: ensure FIFO levels are set correctly in non-DMA mode"
  Revert "tty: serial: OMAP: transmit FIFO threshold interrupts don't wake the chip"
  serial: Fix wakeup init logic to speed up startup
  docbook: don't use serial_core.h in device-drivers book
  serial: amba-pl011: lock console writes against interrupts
  amba-pl011: do not disable RTS during shutdown
  tty: serial: OMAP: transmit FIFO threshold interrupts don't wake the chip
  tty: serial: OMAP: ensure FIFO levels are set correctly in non-DMA mode
  omap-serial: make serial_omap_restore_context depend on CONFIG_PM_RUNTIME
  omap-serial :Make the suspend/resume functions depend on CONFIG_PM_SLEEP.
  TTY: fix UV serial console regression
  jsm: Fixed EEH recovery error
  Updated TTY MAINTAINERS info
  serial: group all the 8250 related code together