Commit Graph

248 Commits

Author SHA1 Message Date
Thomas Gleixner
1621633323 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  51 franklin street fifth floor boston ma 02110 1301 usa

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option [no]_[pad]_[ctrl] any later version this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 51 franklin street fifth floor boston ma
  02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 176 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154040.652910950@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:39 +02:00
Heiner Kallweit
b8f5fe3bc5 i2c: core: add device-managed version of i2c_new_dummy
i2c_new_dummy is typically called from the probe function of the
driver for the primary i2c client. It requires calls to
i2c_unregister_device in the error path of the probe function and
in the remove function.
This can be simplified by introducing a device-managed version.

Note the changed error case return value type: i2c_new_dummy returns
NULL whilst devm_i2c_new_dummy_device returns an ERR_PTR.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
[wsa: rename new functions and fix minor kdoc issues]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-05-17 19:29:40 +02:00
Wolfram Sang
4db61c2a16 i2c: core: ratelimit 'transfer when suspended' errors
There are two problems with WARN_ON() here. One: It is not ratelimited.
Two: We don't see which adapter was used when trying to transfer
something when already suspended. Implement a custom ratelimit once per
adapter and use dev_WARN there. This fixes both issues. Drawback is that
we don't see if multiple drivers are trying to transfer with the same
adapter while suspended. They need to be discovered one after the other
now. This is better than a high CPU load because a really broken driver
might try to resend endlessly.

Fixes: 9ac6cb5fbb ("i2c: add suspended flag and accessors for i2c adapters")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org # v5.1+
2019-05-03 15:25:00 +02:00
Wolfram Sang
63b96983a5 i2c: core: introduce callbacks for atomic transfers
We had the request to access devices very late when interrupts are not
available anymore multiple times now. Mostly to prepare shutdown or
reboot. Allow adapters to specify a specific callback for this case.
Note that we fall back to the generic {master|smbus}_xfer callback if
this new atomic one is not present. This is intentional to preserve the
previous behaviour and avoid regressions. Because there are drivers not
using interrupts or because it might have worked "accidently" before.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Stefan Lengfeld <contact@stefanchrist.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-04-16 13:08:11 +02:00
Wolfram Sang
f6ac28d616 i2c: apply coding style for struct i2c_adapter
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-27 14:14:50 +01:00
Jim Broadus
93b6604c5a i2c: Allow recovery of the initial IRQ by an I2C client device.
A previous change allowed I2C client devices to discover new IRQs upon
reprobe by clearing the IRQ in i2c_device_remove. However, if an IRQ was
assigned in i2c_new_device, that information is lost.

For example, the touchscreen and trackpad devices on a Dell Inspiron laptop
are I2C devices whose IRQs are defined by ACPI extended IRQ types. The
client device structures are initialized during an ACPI walk. After
removing the i2c_hid device, modprobe fails.

This change caches the initial IRQ value in i2c_new_device and then resets
the client device IRQ to the initial value in i2c_device_remove.

Fixes: 6f108dd70d ("i2c: Clear client->irq in i2c_device_remove")
Signed-off-by: Jim Broadus <jbroadus@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
[wsa: this is an easy to backport fix for the regression. We will
refactor the code to handle irq assignments better in general.]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-24 14:43:22 +01:00
Andy Shevchenko
b33a02aadc i2c: acpi: Move I2C bits from acpi.h to i2c.h
As discussed previously the best location for certain bus related bits,
e.g. I2C, is its own realm of the headers.

In order to uncontaminate acpi.h move the I2C bits to i2c.h.

There is no functional change intended.

Link: https://lkml.org/lkml/2018/11/28/744
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-15 23:20:02 +01:00
Wolfram Sang
9ac6cb5fbb i2c: add suspended flag and accessors for i2c adapters
A few drivers open code the handling of suspended adapters. It could be
handled by the core, though, to ensure generic handling. This patch adds
the flag and accessor functions. The usage of these helpers is optional,
though. See the kerneldoc in this patch. Using the new flag, we now
reject further transfers if the adapter is already marked suspended.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:01:07 +01:00
Wolfram Sang
82fe39a6bc i2c: refactor function to release a DMA safe buffer
a) rename to 'put' instead of 'release' to match 'get' when obtaining
   the buffer
b) change the argument order to have the buffer as first argument
c) add a new argument telling the function if the message was
   transferred. This allows the function to be used also in cases
   where setting up DMA failed, so the buffer needs to be freed without
   syncing to the message buffer.

Also convert the only user.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-30 23:13:15 +02:00
Wolfram Sang
0c36dd37d5 i2c: remove deprecated attach_adapter callback
There aren't any users left. Remove this callback from the 2.4 times.
Phew, finally, that took years to reach...

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24 14:42:45 +02:00
Andy Shevchenko
4717be73c2 i2c: core: Parse SDA hold time from firmware
There are two drivers already using the SDA hold time setting.
It might be more in the future, thus, make I2C core to parse the setting
for us if provided by firmware.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-08 22:28:52 +02:00
Wolfram Sang
d9cfe2ce24 i2c: quirks: add zero length checks
Some adapters do not support a message length of 0. Add this as a quirk
so drivers don't have to open code it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-04 23:24:03 +02:00
Wolfram Sang
7ca5f6be79 i2c: recovery: add get_bus_free callback
Some IP cores have an internal 'bus free' logic which may be more
advanced than just checking if SDA is high. Add a separate callback to
get this status. Filling it is optional.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-17 10:46:51 +02:00
Wolfram Sang
ffc59c496b i2c: recovery: require either get_sda or set_sda
For bus recovery, we either need to bail out early if we can read SDA or
we need to send STOP after every pulse. Otherwise recovery might be
misinterpreted as an unwanted write. So, require one of those SDA
handling functions to avoid this problem.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-17 10:41:55 +02:00
Wolfram Sang
fb2896a779 Merge branch 'i2c/precise-locking-names_immutable' into i2c/for-4.19 2018-07-13 00:12:53 +02:00
Peter Rosin
3f3a89e1d7 i2c: remove i2c_lock_adapter and use i2c_lock_bus directly
The i2c_lock_adapter name is ambiguous since it is unclear if it
refers to the root adapter or the adapter you name in the argument.
The natural interpretation is the adapter you name in the argument,
but there are historical reasons for that not being the case; it
in fact locks the root adapter. Just remove the function and force
users to spell out the I2C_LOCK_ROOT_ADAPTER name to indicate what
is really going on. Also remove i2c_unlock_adapter, of course.

This patch was generated with

git grep -l 'i2c_\(un\)\?lock_adapter' \
| xargs sed -i 's/i2c_\(un\)\?lock_adapter(\([^)]*\))/'\
'i2c_\1lock_bus(\2, I2C_LOCK_ROOT_ADAPTER)/g'

followed by white-space touch-up.

Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-13 00:09:37 +02:00
Peter Rosin
63453b59e4 i2c: smbus: add unlocked __i2c_smbus_xfer variant
Removes all locking from i2c_smbus_xfer and renames it to __i2c_smbus_xfer,
then adds a new i2c_smbus_xfer function that simply grabs the lock while
calling the unlocked variant.

This is not perfectly equivalent, since i2c_smbus_xfer was callable from
atomic/irq context if you happened to end up emulating SMBus with an I2C
transfer, and that is no longer the case with this patch. It is unknown
(to me) if anything depends on that quirk, but it seems fragile enough to
simply break those cases and require them to call i2c_transfer directly
instead.

While at it, for consistency rename the 2nd to last argument (size) of
the i2c_smbus_xfer declaration to protocol and remove the surplus extern
marker.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03 22:57:25 +02:00
Boris Brezillon
da0086d018 i2c: Export of_i2c_get_board_info()
I3C busses have to know about all I2C devices connected on the I3C bus
to properly initialize the I3C master, and I2C frames can't be sent on
the bus until this initialization is done.

We can't let the I2C core parse the DT and instantiate I2C devices as
part of its i2c_add_adapter() procedure because, when done this way,
I2C devices are directly registered to the device-model and might be
attached to drivers which could in turn start sending frames on the bus,
which won't work since, as said above, the bus is not yet initialized.

Export of_i2c_register_device() in order to let the I3C core parse the
I2C device nodes by itself and initialize the bus.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-22 13:42:16 +02:00
Boris Brezillon
4fad8868af i2c: Get rid of i2c_board_info->archdata
The only user of i2c_board_info->archdata is the OF parsing code and it
just pass a zero-initialized object which has the same effect as leaving
->archdata to NULL since the client object is allocated with kzalloc().

Get rid of this useless field.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-15 10:42:20 +02:00
Peter Rosin
dde67eb1be i2c: add i2c_get_device_id() to get the standard i2c device id
Can be used during probe to double check that the probed device is
what is expected.

Loosely based on code from Adrian Fiergolski <adrian.fiergolski@cern.ch>.

Tested-by: Adrian Fiergolski <adrian.fiergolski@cern.ch>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
2018-03-06 10:57:59 +01:00
Wolfram Sang
8092178ffe i2c: add 'set_sda' to bus_recovery_info
This will be needed when we want to create STOP conditions, too, later.
Create the needed fields and populate them for the GPIO case if the GPIO
is set to output.

Tested-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-16 00:04:19 +01:00
Wolfram Sang
6c92204e44 i2c: add identifier in declarations for i2c_bus_recovery
No reason to have them undefined, so let's add them.

Tested-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-16 00:04:03 +01:00
Wolfram Sang
766a4f27f3 i2c: make kerneldoc about bus recovery more precise
"Used internally" is vague. What it actually means is that those fields
are populated by the core if valid GPIOs are provided. Change the
comments to reflect that.

Tested-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-16 00:04:02 +01:00
Wolfram Sang
ba98645c7d i2c: add i2c_master_{send|recv}_dmasafe
Use the new helper to create variants of i2c_master_{send|recv} which
mark their buffers as DMA safe.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03 21:23:38 +01:00
Wolfram Sang
8a91732b3b i2c: refactor i2c_master_{send_recv}
Those two functions are very similar, the only differences are that one
needs the I2C_M_RD flag for its message while the other one needs the
buffer casted to drop the const. Introduce a generic helper which allows
to specify the flags (also needed later for DMA safe variants of these
calls) and let the casting be done in the inlining functions which are
now calling the new helper function.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03 21:22:29 +01:00