Commit graph

243 commits

Author SHA1 Message Date
Jean Delvare
01590f361e i2c: i801: Instantiate SPD EEPROMs automatically
Call the function to instantiate SPD EEPROMs automatically on the
main SMBus controller.

Multiplexed SMBus systems are excluded for now as they are more
complex to handle.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-29 12:55:47 +02:00
Geert Uytterhoeven
be1b92c133 i2c: i801: Use GPIO_LOOKUP() helper macro
i801_add_mux() fills in the GPIO lookup table by manually populating an
array of gpiod_lookup structures.  Use the existing GPIO_LOOKUP() helper
macro instead, to relax a dependency on the gpiod_lookup structure's
member names.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-15 12:57:01 +02:00
Mika Westerberg
04bbb97d1b i2c: i801: Do not add ICH_RES_IO_SMI for the iTCO_wdt device
Martin noticed that nct6775 driver does not load properly on his system
in v5.4+ kernels. The issue was bisected to commit b84398d6d7 ("i2c:
i801: Use iTCO version 6 in Cannon Lake PCH and beyond") but it is
likely not the culprit because the faulty code has been in the driver
already since commit 9424693035 ("i2c: i801: Create iTCO device on
newer Intel PCHs"). So more likely some commit that added PCI IDs of
recent chipsets made the driver to create the iTCO_wdt device on Martins
system.

The issue was debugged to be PCI configuration access to the PMC device
that is not present. This returns all 1's when read and this caused the
iTCO_wdt driver to accidentally request resourses used by nct6775.

It turns out that the SMI resource is only required for some ancient
systems, not the ones supported by this driver. For this reason do not
populate the SMI resource at all and drop all the related code. The
driver now always populates the main I/O resource and only in case of SPT
(Intel Sunrisepoint) compatible devices it adds another resource for the
NO_REBOOT bit. These two resources are of different types so
platform_get_resource() used by the iTCO_wdt driver continues to find
the both resources at index 0.

Link: https://lore.kernel.org/linux-hwmon/CAM1AHpQ4196tyD=HhBu-2donSsuogabkfP03v1YF26Q7_BgvgA@mail.gmail.com/
Fixes: 9424693035 ("i2c: i801: Create iTCO device on newer Intel PCHs")
[wsa: complete fix needs all of http://patchwork.ozlabs.org/project/linux-i2c/list/?series=160959&state=*]
Reported-by: Martin Volf <martin.volf.42@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-10 10:27:11 +01:00
Jarkko Nikula
f53938d2c7 i2c: i801: Add support for Intel Comet Lake PCH-V
Add support for Intel Comet Lake PCH-V which is based on Intel Kaby
Lake. Difference between it and other Comet Lake variants is that former
uses previous iTCO version 4 and latter use version 6 like Intel Cannon
Lake PCH.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-29 22:06:01 +01:00
Wolfram Sang
41d06630b4 i2c: i801: convert to use i2c_new_client_device()
Move away from the deprecated API and return the shiny new ERRPTR where
useful.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-15 20:39:17 +01:00
Andy Shevchenko
790591f41e i2c: i801: Correct Intel Jasper Lake SOC naming
There is no suffix applied to Intel Jasper Lake SOC. Remove it
from the comments and definitions. Besides that, it's a SOC,
thus replace PCH with SOC where it appropriate.

Fixes: e0c61c0479 ("i2c: i801: Add support for Intel Jasper Lake")
Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-11-25 15:52:35 +01:00
Jarkko Nikula
07f047e3fe i2c: i801: Add support for Intel Comet Lake PCH-H
Add support for another Intel Comet Lake variant.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-10-24 20:31:34 +02:00
Jarkko Nikula
e0c61c0479 i2c: i801: Add support for Intel Jasper Lake
Add support for SMBus controller on Intel Jasper Lake PCH-N.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-10-24 20:31:23 +02:00
Jarkko Nikula
fd4b204a09 i2c: i801: Bring back Block Process Call support for certain platforms
Commit b84398d6d7 ("i2c: i801: Use iTCO version 6 in Cannon Lake PCH
and beyond") looks like to drop by accident Block Write-Block Read Process
Call support for Intel Sunrisepoint, Lewisburg, Denverton and Kaby Lake.

That support was added for above and newer platforms by the commit
315cd67c94 ("i2c: i801: Add Block Write-Block Read Process Call
support") so bring it back for above platforms.

Fixes: b84398d6d7 ("i2c: i801: Use iTCO version 6 in Cannon Lake PCH and beyond")
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-09-28 20:44:12 +02:00
Linus Torvalds
351c8a09b0 Merge branch 'i2c/for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - new driver for ICY, an Amiga Zorro card :)

 - axxia driver gained slave mode support, NXP driver gained ACPI

 - the slave EEPROM backend gained 16 bit address support

 - and lots of regular driver updates and reworks

* 'i2c/for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (52 commits)
  i2c: tegra: Move suspend handling to NOIRQ phase
  i2c: imx: ACPI support for NXP i2c controller
  i2c: uniphier(-f): remove all dev_dbg()
  i2c: uniphier(-f): use devm_platform_ioremap_resource()
  i2c: slave-eeprom: Add comment about address handling
  i2c: exynos5: Remove IRQF_ONESHOT
  i2c: stm32f7: Make structure stm32f7_i2c_algo constant
  i2c: cht-wc: drop check because i2c_unregister_device() is NULL safe
  i2c-eeprom_slave: Add support for more eeprom models
  i2c: fsi: Add of_put_node() before break
  i2c: synquacer: Make synquacer_i2c_ops constant
  i2c: hix5hd2: Remove IRQF_ONESHOT
  i2c: i801: Use iTCO version 6 in Cannon Lake PCH and beyond
  watchdog: iTCO: Add support for Cannon Lake PCH iTCO
  i2c: iproc: Make bcm_iproc_i2c_quirks constant
  i2c: iproc: Add full name of devicetree node to adapter name
  i2c: piix4: Add ACPI support
  i2c: piix4: Fix probing of reserved ports on AMD Family 16h Model 30h
  i2c: ocores: use request_any_context_irq() to register IRQ handler
  i2c: designware: Fix optional reset error handling
  ...
2019-09-24 16:48:02 -07:00
Linus Torvalds
7c672abc12 It's a somewhat calmer cycle for docs this time, as the churn of the mass
RST conversion is happily mostly behind us.
 
  - A new document on reproducible builds.
 
  - We finally got around to zapping the documentation for hardware support
    that was removed in 2004; one doesn't want to rush these things.
 
  - The usual assortment of fixes, typo corrections, etc.
 
 You'll still find a handful of annoying conflicts against other trees,
 mostly tied to the last RST conversions; resolutions are straightforward
 and the linux-next ones are good.
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Merge tag 'docs-5.4' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It's a somewhat calmer cycle for docs this time, as the churn of the
  mass RST conversion is happily mostly behind us.

   - A new document on reproducible builds.

   - We finally got around to zapping the documentation for hardware
     support that was removed in 2004; one doesn't want to rush these
     things.

   - The usual assortment of fixes, typo corrections, etc"

* tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits)
  Documentation: kbuild: Add document about reproducible builds
  docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi]
  Documentation: Add "earlycon=sbi" to the admin guide
  doc🔒 remove reference to clever use of read-write lock
  devices.txt: improve entry for comedi (char major 98)
  docs: mtd: Update spi nor reference driver
  doc: arm64: fix grammar dtb placed in no attributes region
  Documentation: sysrq: don't recommend 'S' 'U' before 'B'
  mailmap: Update email address for Quentin Perret
  docs: ftrace: clarify when tracing is disabled by the trace file
  docs: process: fix broken link
  Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title
  Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command
  Documentation/arm/sa1100: Remove some obsolete documentation
  docs/zh_CN: update Chinese howto.rst for latexdocs making
  Documentation: virt: Fix broken reference to virt tree's index
  docs: Fix typo on pull requests guide
  kernel-doc: Allow anonymous enum
  Documentation: sphinx: Don't parse socket() as identifier reference
  Documentation: sphinx: Add missing comma to list of strings
  ...
2019-09-17 16:22:26 -07:00
Mika Westerberg
b84398d6d7 i2c: i801: Use iTCO version 6 in Cannon Lake PCH and beyond
Intel Cannon Lake PCH moved the NO_REBOOT bit to reside as part of the
TCO registers instead so update the i2c-i801 driver so that for Cannon
Lake and beyond register platform device for iTCO using version 6. The
affected PCHs are Cannon Lake, Cedar Fork, Comet Lake, Elkhart Lake and
Ice Lake.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-09-03 19:48:02 +02:00
Andy Shevchenko
01641b266d i2c: i801: Avoid memory leak in check_acpi_smo88xx_device()
check_acpi_smo88xx_device() utilizes acpi_get_object_info() which in its turn
allocates a buffer. User is responsible to clean allocated resources. The last
has been missed in the original code. Fix it here.

While here, replace !ACPI_SUCCESS() with ACPI_FAILURE().

Fixes: 19b07cb4a1 ("i2c: i801: Register optional lis3lv02d I2C device on Dell machines")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-08-29 20:46:48 +02:00
Chuhong Yuan
7735eeebd2 i2c: busses: Use dev_get_drvdata where possible
Instead of using to_pci_dev + pci_get_drvdata,
use dev_get_drvdata to make code simpler.

Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-08-01 14:55:22 +02:00
Mauro Carvalho Chehab
ccf988b66d docs: i2c: convert to ReST and add to driver-api bookset
Convert each file at I2C subsystem, renaming them to .rst and
adding to the driver-api book.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-07-31 13:25:27 -06:00
Linus Torvalds
273cbf61c3 Merge branch 'i2c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "New stuff from the I2C world:

   - in the core, getting irqs from ACPI is now similar to OF

   - new driver for MediaTek MT7621/7628/7688 SoCs

   - bcm2835, i801, and tegra drivers got some more attention

   - GPIO API cleanups

   - cleanups in the core headers

   - lots of usual driver updates"

* 'i2c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (74 commits)
  i2c: mt7621: Fix platform_no_drv_owner.cocci warnings
  i2c: cpm: remove casting dma_alloc
  dt-bindings: i2c: sun6i-p2wi: Fix the binding example
  dt-bindings: i2c: mv64xxx: Fix the example compatible
  i2c: i801: Documentation update
  i2c: i801: Add support for Intel Tiger Lake
  i2c: i801: Fix PCI ID sorting
  dt-bindings: i2c-stm32: document optional dmas
  i2c: i2c-stm32f7: Add I2C_SMBUS_I2C_BLOCK_DATA support
  i2c: core: Tidy up handling of init_irq
  i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
  i2c: core: Move ACPI IRQ handling to probe time
  i2c: acpi: Factor out getting the IRQ from ACPI
  i2c: acpi: Use available IRQ helper functions
  i2c: core: Allow whole core to use i2c_dev_irq_from_resources
  eeprom: at24: modify a comment referring to platform data
  dt-bindings: i2c: omap: Add new compatible for J721E SoCs
  dt-bindings: i2c: mv64xxx: Add YAML schemas
  dt-bindings: i2c: sun6i-p2wi: Add YAML schemas
  i2c: mt7621: Add MediaTek MT7621/7628/7688 I2C driver
  ...
2019-07-15 21:10:39 -07:00
Jarkko Nikula
051d769f0a i2c: i801: Add support for Intel Tiger Lake
Add SMBUS PCI ID for Intel Tiger Lake -LP.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-07-05 20:59:10 +02:00
Jarkko Nikula
856078bf64 i2c: i801: Fix PCI ID sorting
I managed to break sorting in PCI ID defines in my last two patches:

commit 5cd1c56c42 ("i2c: i801: Add support for Intel Comet Lake")
commit 9be1485acc ("i2c: i801: Add support for Intel Elkhart Lake")

Fix them up.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-07-05 20:59:10 +02:00
Wolfram Sang
45c9cc681d Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-5.3
I realize that there are changes in drivers/i2c/busses/i2c-i801.c that strictly
speaking don't belong here, but I hope you don't mind. These changes are all
about the interaction with the i2c-mux-gpio code, and I did a test-merge a few
days ago w/o conflicts.

Anyway, the GPIO-work from Linus Walleij (with help from Serge Semin) in the
i2c-mux-gpio and i2c-arb-gpio-challenge drivers is the main feature.
2019-06-29 13:02:48 +02:00
Linus Walleij
d308dfbf62 i2c: mux/i801: Switch to use descriptor passing
This switches the i801 GPIO mux to use GPIO descriptors for
handling the GPIO lines. The previous hack which was reaching
inside the GPIO chips etc cannot live on. We pass descriptors
along with the GPIO mux device at creation instead.

The GPIO mux was only used by way of platform data with a
platform device from one place in the kernel: the i801 i2c bus
driver. Let's just associate the GPIO descriptor table with
the actual device like everyone else and dynamically create
a descriptor table passed along with the GPIO i2c mux.

This enables simplification of the GPIO i2c mux driver to
use only the descriptor API and the OF probe path gets
simplified in the process.

The i801 driver was registering the GPIO i2c mux with
PLATFORM_DEVID_AUTO which would make it hard to predict the
device name and assign the descriptor table properly, but
this seems to be a mistake to begin with: all of the
GPIO mux devices are hardcoded to look up GPIO lines from
the "gpio_ich" GPIO chip. If there are more than one mux,
there is certainly more than one gpio chip as well, and
then we have more serious problems. Switch to
PLATFORM_DEVID_NONE instead. There can be only one.

Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Jean Delvare <jdelvare@suse.com>
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[Removed a newline, suggested by Andy. /Peter]
Signed-off-by: Peter Rosin <peda@axentia.se>
2019-06-22 07:01:34 +02:00
Jarkko Nikula
9be1485acc i2c: i801: Add support for Intel Elkhart Lake
Add PCI ID for Intel Elkhart Lake PCH.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-21 23:22:52 +02:00
Alexander Sverdlin
315cd67c94 i2c: i801: Add Block Write-Block Read Process Call support
Add SMBUS 2.0 Block Write-Block Read Process Call command support.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-21 23:21:37 +02:00
Andy Shevchenko
af668d6518 i2c: i801: Use match_string() helper to simplify the code
match_string() returns the array index of a matching string.
Use it instead of the open-coded implementation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-21 23:09:24 +02:00
Andy Shevchenko
aa5ae06515 i2c: i801: Fix kernel crash in is_dell_system_with_lis3lv02d()
The commit

  19b07cb4a1 ("i2c: i801: Register optional lis3lv02d I2C device on Dell machines")

introduced a new check in order to enumerate some slave devices on Dell
machines. Though, it brings a regression on machines where DMI vendor is not set.

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] SMP PTI
 CPU: 8 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc4-next-20190613+ #317
 RIP: 0010:strcmp+0xc/0x20

To fix this crash, check if vendor field is present before accessing to it.

Fixes: 19b07cb4a1 ("i2c: i801: Register optional lis3lv02d I2C device on Dell machines")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-14 23:24:33 +02:00
Pali Rohár
19b07cb4a1 i2c: i801: Register optional lis3lv02d I2C device on Dell machines
Dell platform team told us that some (DMI whitelisted) Dell Latitude
machines have ST microelectronics accelerometer at I2C address 0x29.

Presence of that ST microelectronics accelerometer is verified by existence
of SMO88xx ACPI device which represent that accelerometer. Unfortunately
ACPI device does not specify I2C address.

This patch registers lis3lv02d device for selected Dell Latitude machines
at I2C address 0x29 after detection. And for Dell Vostro V131 machine at
I2C address 0x1d which was manually detected.

Finally commit a7ae81952c ("i2c: i801: Allow ACPI SystemIO OpRegion to
conflict with PCI BAR") allowed to use i2c-i801 driver on Dell machines so
lis3lv02d correctly initialize accelerometer.

Tested on Dell Latitude E6440.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-08 00:13:44 +02:00
Thomas Gleixner
c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 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

  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 [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] 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

  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 [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00
Jarkko Nikula
5cd1c56c42 i2c: i801: Add support for Intel Comet Lake
Add PCI ID for Intel Comet Lake PCH.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20 17:42:23 +01:00
Felipe Balbi
851a151148 i2c: i801: fix DNV's SMBCTRL register offset
DNV's iTCO is slightly different with SMBCTRL sitting at a different
offset when compared to all other devices. Let's fix so that we can
properly use iTCO watchdog.

Fixes: 84d7f2ebd7 ("i2c: i801: Add support for Intel DNV")
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-09-04 18:04:55 +02:00
Mika Westerberg
7fd6d98b89 i2c: i801: Allow ACPI AML access I/O ports not reserved for SMBus
Commit 7ae81952cda ("i2c: i801: Allow ACPI SystemIO OpRegion to conflict
with PCI BAR") made it possible for AML code to access SMBus I/O ports
by installing custom SystemIO OpRegion handler and blocking i80i driver
access upon first AML read/write to this OpRegion.

However, while ThinkPad T560 does have SystemIO OpRegion declared under
the SMBus device, it does not access any of the SMBus registers:

    Device (SMBU)
    {
        ...

        OperationRegion (SMBP, PCI_Config, 0x50, 0x04)
        Field (SMBP, DWordAcc, NoLock, Preserve)
        {
            ,   5,
            TCOB,   11,
            Offset (0x04)
        }

        Name (TCBV, 0x00)
        Method (TCBS, 0, NotSerialized)
        {
            If ((TCBV == 0x00))
            {
            TCBV = (\_SB.PCI0.SMBU.TCOB << 0x05)
            }

            Return (TCBV) /* \_SB_.PCI0.SMBU.TCBV */
        }

        OperationRegion (TCBA, SystemIO, TCBS (), 0x10)
        Field (TCBA, ByteAcc, NoLock, Preserve)
        {
            Offset (0x04),
            ,   9,
            CPSC,   1
        }
    }

Problem with the current approach is that it blocks all I/O port access
and because this system has touchpad connected to the SMBus controller
after first AML access (happens during suspend/resume cycle) the
touchpad fails to work anymore.

Fix this so that we allow ACPI AML I/O port access if it does not touch
the region reserved for the SMBus.

Fixes: 7ae81952cda ("i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200737
Reported-by: Yussuf Khalil <dev@pp3345.net>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-30 22:53:44 +02:00
Mika Westerberg
0bff2a8610 i2c: i801: Add support for Intel Ice Lake
Intel Ice Lake has the same SMBus host controller than Intel Cannon
Lake. Add the PCI ID to the drivers list of supported devices.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[jarkko.nikula@linux.intel.com: Add entries to Documentation and Kconfig]
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03 23:26:44 +02:00
Wolfram Sang
3d8b7a4ea3 Merge branch 'i2c/platform_data-immutable' into i2c/for-4.18 2018-05-17 16:29:19 +02:00
Wolfram Sang
62ea22c495 i2c: mux: gpio: move header to platform_data
This header only contains platform_data. Move it to the proper directory.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
2018-05-17 16:27:52 +02:00
Anders Roxell
4b2f9bd5e3 i2c: i801: fix unused-function warning
With CONFIG_PM, we get a harmless build warning:
drivers/i2c/busses/i2c-i801.c:1723:12: warning: ‘i801_resume’ defined but not used [-Wunused-function]
 static int i801_resume(struct device *dev)
            ^~~~~~~~~~~
drivers/i2c/busses/i2c-i801.c:1714:12: warning: ‘i801_suspend’ defined but not used [-Wunused-function]
 static int i801_suspend(struct device *dev)
            ^~~~~~~~~~~~

Follow design pattern from other drivers like i2c-brcmstb, i2c-mpc,
i2c-ocores, i2c-pnx, i2c-puv3, i2c-st, i2c-stu300 and i2c-mux-pca954x
and changing the ifdef CONFIG_PM to CONFIG_PM_SLEEP.

Fixes: a9c8088c79 ("i2c: i801: Don't restore config registers on runtime PM")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-17 15:54:12 +02:00
Jean Delvare
a9c8088c79 i2c: i801: Don't restore config registers on runtime PM
Restoring configuration registers is only needed when we hand control
to the firmware. This is never the case with runtime power
management. The device will autosuspend whenever not used, so avoid
useless register writes by defining suspend/resume only, and not
runtime_suspend/runtime_resume.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30 10:39:28 +02:00
Jean Delvare
f7f6d915a1 i2c: i801: Restore configuration at shutdown
On some systems, the BIOS expects certain SMBus register values to
match the hardware defaults. Restore these configuration registers at
shutdown time to avoid confusing the BIOS. This avoids hard-locking
such systems upon reboot.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org
2018-04-11 23:08:13 +02:00
Jean Delvare
a086bb8317 i2c: i801: Save register SMBSLVCMD value only once
Saving the original value of register SMBSLVCMD in
i801_enable_host_notify() doesn't work, because this function is
called not only at probe time but also at resume time. Do it in
i801_probe() instead, so that the saved value is not overwritten at
resume time.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 22e94bd677 ("i2c: i801: store and restore the SLVCMD register at load and unload")
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org	# v4.10+
2018-04-11 23:07:14 +02:00
Jarkko Nikula
1540779883 i2c: i801: Add missing documentation entries for Braswell and Kaby Lake
Commits adding PCI IDs for Intel Braswell and Kaby Lake PCH-H lacked the
respective Kconfig and Documentation/i2c/busses/i2c-i801 change. Add
them now.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-02-21 09:17:20 +01:00
Hans de Goede
6e0c9507bf i2c: i801: Fix Failed to allocate irq -2147483648 error
On Apollo Lake devices the BIOS does not set up IRQ routing for the i801
SMBUS controller IRQ, so we end up with dev->irq set to IRQ_NOTCONNECTED.

Detect this and do not try to use the irq in this case silencing:
i801_smbus 0000:00:1f.1: Failed to allocate irq -2147483648: -107

Cc: stable@vger.kernel.org
BugLink: https://communities.intel.com/thread/114759
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27 19:11:27 +01:00
Jarkko Nikula
cb09d943c7 i2c: i801: Add support for Intel Cedar Fork
Add PCI ID for Intel Cedar Fork PCH.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-05 14:44:56 +02:00
Qiuxu Zhuo
bfd4473b85 i2c: i801: Restore the presence state of P2SB PCI device after reading BAR
Sun, Yunying reported the following failure on Denverton micro-server:

 EDAC DEBUG: pnd2_init:
 EDAC DEBUG: pnd2_probe:
 EDAC DEBUG: dnv_rd_reg: Read b_cr_tolud_pci=00000000_80000000
 EDAC DEBUG: dnv_rd_reg: Read b_cr_touud_lo_pci=00000000_80000000
 EDAC DEBUG: dnv_rd_reg: Read b_cr_touud_hi_pci=00000000_00000004
 EDAC DEBUG: dnv_rd_reg: Read b_cr_asym_mem_region0_mchbar=00000000_00000000
 EDAC DEBUG: dnv_rd_reg: Read b_cr_asym_mem_region1_mchbar=00000000_00000000
 EDAC DEBUG: dnv_rd_reg: Read b_cr_mot_out_base_mchbar=00000000_00000000
 EDAC DEBUG: dnv_rd_reg: Read b_cr_mot_out_mask_mchbar=00000000_00000000
 EDAC pnd2: Failed to register device with error -19.

On Denverton micro-server, the presence of the P2SB bridge PCI device is
enabled or disabled by the item 'RelaxSecConf' in BIOS setup menu. When
'RelaxSecConf' is enabled, the P2SB PCI device is present and the pnd2_edac
EDAC driver also uses it to get BAR. Hiding the P2SB PCI device caused the
pnd2_edac EDAC driver failed to get BAR then reported the above failure.

Therefor, store the presence state of P2SB PCI device before unhiding it
for reading BAR and restore the presence state after reading BAR.

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Reported-by: Yunying Sun <yunying.sun@intel.com>
Tested-by: Yunying Sun <yunying.sun@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-28 17:29:48 +02:00
Srinivas Pandruvada
09a1de04d5 i2c: i801: Add support for Intel Cannon Lake
Added SMBUS PCI Ids for SMBUS for Cannon Lake PCH.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[jarkko.nikula@linux.intel.com: Add entries to Documentation and Kconfig.
Cover Cannon Lake-H too]
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-19 16:17:41 +02:00
Mika Westerberg
9827f9eb79 i2c: i801: Add support for Intel Gemini Lake
Intel Gemini Lake has the same SMBus host controller than Intel Broxton.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:39:16 +01:00
Benjamin Tissoires
4d5538f588 i2c: use an IRQ to report Host Notify events, not alert
The current SMBus Host Notify implementation relies on .alert() to
relay its notifications. However, the use cases where SMBus Host
Notify is needed currently is to signal data ready on touchpads.

This is closer to an IRQ than a custom API through .alert().
Given that the 2 touchpad manufacturers (Synaptics and Elan) that
use SMBus Host Notify don't put any data in the SMBus payload, the
concept actually matches one to one.

Benefits are multiple:
- simpler code and API: the client will just have an IRQ, and
  nothing needs to be added in the adapter beside internally
  enabling it.
- no more specific workqueue, the threading is handled by IRQ core
  directly (when required)
- no more races when removing the device (the drivers are already
  required to disable irq on remove)
- simpler handling for drivers: use plain regular IRQs
- no more dependency on i2c-smbus for i2c-i801 (and any other adapter)
- the IRQ domain is created automatically when the adapter exports
  the Host Notify capability
- the IRQ are assign only if ACPI, OF and the caller did not assign
  one already
- the domain is automatically destroyed on remove
- fewer lines of code (minus 20, yeah!)

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:22:06 +01:00
Benjamin Tissoires
c912a25a5a i2c: i801: remove SMBNTFDDAT reads as they always seem to return 0
On the platform tested, reading SMBNTFDDAT always returns 0 (using 1 read
of a word or 2 of 2 bytes). Given that we are not sure why and that we
don't need to rely on the data parameter in the current users of Host
Notify, remove this part of the code.

If someone wants to re-enable it, just revert this commit and data should
be available.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:22:05 +01:00
Benjamin Tissoires
f91fba627c i2c: i801: use the BIT() macro for FEATURES_* also
no functional changes

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:22:04 +01:00
Benjamin Tissoires
fe9ba3ec1b i2c: i801: use BIT() macro for bits definition
i801 mixes hexadecimal and decimal values for defining bits. However,
we have a nice BIT() macro for this exact purpose.

No functional changes, cleanup only.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:22:03 +01:00
Benjamin Tissoires
9786b1f19e i2c: i801: minor formatting issues
No functional changes, just typos and remove unused #define.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:22:02 +01:00
Benjamin Tissoires
22e94bd677 i2c: i801: store and restore the SLVCMD register at load and unload
Also do not override any other configuration in this register.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:22:01 +01:00
Jean Delvare
ba9ad2af70 i2c: i801: Fix I2C Block Read on 8-Series/C220 and later
Starting with the 8-Series/C220 PCH (Lynx Point), the SMBus
controller includes a SPD EEPROM protection mechanism. Once the SPD
Write Disable bit is set, only reads are allowed to slave addresses
0x50-0x57.

However the legacy implementation of I2C Block Read since the ICH5
looks like a write, and is therefore blocked by the SPD protection
mechanism. This causes the eeprom and at24 drivers to fail.

So assume that I2C Block Read is implemented as an actual read on
these chipsets. I tested it on my Q87 chipset and it seems to work
just fine.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
[wsa: rebased to v4.9-rc2]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25 12:00:01 +02:00
Linus Torvalds
87840a2b7e Merge branch 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Here is the 4.9 pull request from I2C including:

   - centralized error messages when registering to the core
   - improved lockdep annotations to prevent false positives
   - DT support for muxes, gates, and arbitrators
   - bus speeds can now be obtained from ACPI
   - i2c-octeon got refactored and now supports ThunderX SoCs, too
   - i2c-tegra and i2c-designware got a bigger bunch of updates
   - a couple of standard driver fixes and improvements"

* 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits)
  i2c: axxia: disable clks in case of failure in probe
  i2c: octeon: thunderx: Limit register access retries
  i2c: uniphier-f: fix misdetection of incomplete STOP condition
  gpio: pca953x: variable 'id' was used twice
  i2c: i801: Add support for Kaby Lake PCH-H
  gpio: pca953x: fix an incorrect lockdep warning
  i2c: add a warning to i2c_adapter_depth()
  lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible
  i2c: export i2c_adapter_depth()
  i2c: rk3x: Fix variable 'min_total_ns' unused warning
  i2c: rk3x: Fix sparse warning
  i2c / ACPI: Do not touch an I2C device if it belongs to another adapter
  i2c: octeon: Fix high-level controller status check
  i2c: octeon: Avoid sending STOP during recovery
  i2c: octeon: Fix set SCL recovery function
  i2c: rcar: add support for r8a7796 (R-Car M3-W)
  i2c: imx: make bus recovery through pinctrl optional
  i2c: meson: add gxbb compatible string
  i2c: uniphier-f: set the adapter to master mode when probing
  i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
  ...
2016-10-07 14:12:21 -07:00
Mika Westerberg
1f6dbb022b i2c: i801: Do not create iTCO watchdog when WDAT table exists
ACPI WDAT table is the preferred way to use hardware watchdog over the
native iTCO_wdt. Windows only uses this table for its hardware watchdog
implementation so we should be relatively safe to trust it has been
validated by OEMs

Prevent iTCO watchdog creation if we detect that there is ACPI WDAT table.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-28 23:08:08 +02:00
Andy Shevchenko
31158763ef i2c: i801: Add support for Kaby Lake PCH-H
Intel Kaby Lake PCH-H has the same legacy SMBus host controller than Intel
Sunrisepoint PCH. It also has same iTCO watchdog on the bus.

Add Kaby Lake PCH-H PCI ID to the list of supported devices.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-24 10:57:56 +02:00
Wolfram Sang
ea734404f3 i2c: don't print error when adding adapter fails
The core will do this for us now.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-22 08:19:55 +02:00
Javier Martinez Canillas
175c7080f2 i2c: i801: use IS_ENABLED() instead of checking for built-in or module
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either
built-in or as a module, use that macro instead of open coding the same.

Using the macro makes the code more readable by helping abstract away some
of the Kconfig built-in and module enable details.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-26 08:44:56 +02:00
Benjamin Tissoires
7b0ed334b8 i2c: i801: add support of Host Notify
The i801 chip can handle the Host Notify feature since ICH 3 as mentioned
in http://www.intel.com/content/dam/doc/datasheet/82801ca-io-controller-hub-3-datasheet.pdf

Enable the functionality unconditionally and propagate the alert
on each notification.

With a T440s and a Synaptics touchpad that implements Host Notify, the
payload data is always 0x0000, so I am not sure if the device actually
sends the payload or if there is a problem regarding the implementation.

Tested-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-06 00:39:42 +09:00
Ellen Wang
97d34ec136 i2c: i801: recover from hardware PEC errors
On a CRC error while using hardware-supported PEC, an additional
error bit is set in the auxiliary status register.  If this bit
isn't cleared, all subsequent operations will fail, essentially
hanging the controller.

The fix is simple: check, report, and clear the bit in
i801_check_post().  Also, in case the driver starts with the
hardware in that state, clear it in i801_check_pre() as well.

Signed-off-by: Ellen Wang <ellen@cumulusnetworks.com>
Tested-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-01 22:42:15 +02:00
Jean Delvare
a90bc5d9a7 i2c: i801: Drop needless bit-wise OR
The interrupt handling code makes it look like several status values
may be merged together before being processed, while this will never
happen. Change from bit-wise OR to simple assignment to make it more
obvious and avoid misunderstanding.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-06-13 22:32:09 +02:00
Mika Westerberg
a7ae81952c i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR
Many Intel systems the BIOS declares a SystemIO OpRegion below the SMBus
PCI device as can be seen in ACPI DSDT table from Lenovo Yoga 900:

  Device (SBUS)
  {
      OperationRegion (SMBI, SystemIO, (SBAR << 0x05), 0x10)
      Field (SMBI, ByteAcc, NoLock, Preserve)
      {
          HSTS,   8,
          Offset (0x02),
          HCON,   8,
          HCOM,   8,
          TXSA,   8,
          DAT0,   8,
          DAT1,   8,
          HBDR,   8,
          PECR,   8,
          RXSA,   8,
          SDAT,   16
      }

There are also bunch of AML methods that that the BIOS can use to access
these fields. Most of the systems in question AML methods accessing the
SMBI OpRegion are never used.

Now, because of this SMBI OpRegion many systems fail to load the SMBus
driver with an error looking like one below:

  ACPI Warning: SystemIO range 0x0000000000003040-0x000000000000305F
       conflicts with OpRegion 0x0000000000003040-0x000000000000304F
       (\_SB.PCI0.SBUS.SMBI) (20160108/utaddress-255)
  ACPI: If an ACPI driver is available for this device, you should use
       it instead of the native driver

The reason is that this SMBI OpRegion conflicts with the PCI BAR used by
the SMBus driver.

It turns out that we can install a custom SystemIO address space handler
for the SMBus device to intercept all accesses through that OpRegion. This
allows us to share the PCI BAR with the AML code if it for some reason is
using it. We do not expect that this OpRegion handler will ever be called
but if it is we print a warning and prevent all access from the SMBus
driver itself.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=110041
Reported-by: Andy Lutomirski <luto@kernel.org>
Reported-by: Pali Rohár <pali.rohar@gmail.com>
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org
2016-06-09 21:38:57 +02:00
Jarkko Nikula
a7401ca559 i2c: i801: Add runtime PM support with autosuspend
Allow runtime PM so that PM and PCI core can put the device into low-power
state when idle and resume it back when needed in those platforms that
support PM for i801 device.

Enable also autosuspend with 1 second delay in order to not needlessly
toggle power state on and off if there are multiple transactions during
short time.

Device is resumed at the beginning of bus access and marked idle ready
for autosuspend at the end of it.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-12 23:21:25 +02:00
Jarkko Nikula
2ee73c484d i2c: i801: Convert to struct dev_pm_ops for suspend/resume
Stop using legacy PCI PM support and convert to standard dev_pm_ops.
This provides more straightforward path to add runtime PM.

While at it remove explicit PCI power state control and configuration space
save/restore as the PCI core does it.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-12 23:18:53 +02:00
Linus Torvalds
b852495908 Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Mostly usual driver updates and improvements.  The changelog should
  give an idea.  Standing out is the i2c-qup driver with lots of new
  capabilities and we also have now an i2c-demuxer.

  I'd especially like to welcome Peter Rosin as the i2c-mux maintainer.
  He has an interesting series for muxes in the queue and agreed to look
  after this part of the subsystem.  Thank you, Peter, and welcome
  again!

  The octeon changes were applied pretty recently before the merge
  window.  I am aware.  They are the first (and relatively simple)
  patches of a larger overhaul to this driver.  In case something goes
  wrong with them, they are easy to fix (or revert).  The advantage I
  see is that they are out of the way, and I can concentrate on the next
  block of patches.  I really would like to apply the overhaul in
  smaller batches to avoid regressions.  And waiting a cycle for the
  introductory patches seemed too much of a delay for me"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (39 commits)
  i2c: octeon: Support I2C_M_RECV_LEN
  i2c: octeon: Cleanup resource allocation code
  i2c: octeon: Cleanup i2c-octeon driver
  MAINTAINERS: add Peter Rosin as i2c mux maintainer
  dt-bindings: i2c: Spelling s/propoerty/property/
  i2c: immediately mark ourselves as registered
  i2c: i801: sort IDs alphabetically
  MAINTAINERS: Mika and me are designated reviewers for I2C DESIGNWARE
  i2c: octeon: Cleanup kerneldoc comments
  i2c: do not use internal data from driver core
  i2c: cadence: Fix the kernel-doc warnings
  i2c: imx: remove extra spaces.
  i2c: rcar: don't open code of_device_get_match_data()
  i2c: qup: Fix fifo handling after adding V2 support
  i2c: xiic: Implement power management
  i2c: piix4: Pre-shift the port number
  i2c: piix4: Always use the same type for port
  i2c: piix4: Support alternative port selection register
  i2c: tegra: don't open code of_device_get_match_data()
  i2c: riic, sh_mobile, rcar: Use ARCH_RENESAS
  ...
2016-03-22 12:47:40 -07:00
Andy Shevchenko
34b57f40a6 i2c: i801: sort IDs alphabetically
Sort the list to have a faster search for a certain PCI ID.

There is no functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-03-12 16:59:18 +01:00
Alexandra Yates
1a1503c539 i2c: i801: Adding Intel Lewisburg support for iTCO
Starting from Intel Sunrisepoint (Skylake PCH) the iTCO watchdog
resources have been moved to reside under the i801 SMBus host
controller whereas previously they were under the LPC device.

This patch adds Intel lewisburg SMBus support for iTCO device.
It allows to load watchdog dynamically when the hardware is
present.

Fixes: cdc5a3110e ("i2c: i801: add Intel Lewisburg device IDs")
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Alexandra Yates <alexandra.yates@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-02-18 13:18:48 +01:00
Alexandra Yates
cdc5a3110e i2c: i801: add Intel Lewisburg device IDs
Adding Intel codename Lewisburg platform device IDs for SMBus.

Signed-off-by: Alexandra Yates <alexandra.yates@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-20 16:22:21 +01:00
Dustin Byford
8eb5c87a92 i2c: add ACPI support for I2C mux ports
Although I2C mux devices are easily enumerated using ACPI (_HID/_CID or
device property compatible string match), enumerating I2C client devices
connected through an I2C mux needs a little extra work.

This change implements a method for describing an I2C device hierarchy that
includes mux devices by using an ACPI Device() for each mux channel along
with an _ADR to set the channel number for the device.  See
Documentation/acpi/i2c-muxes.txt for a simple example.

To make this work the ismt, i801, and designware pci/platform devs now
share an ACPI companion with their I2C adapter dev similar to how it's done
in OF.  This is done on the assumption that power management functions will
not be called directly on the I2C dev that is sharing the ACPI node.

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Dustin Byford <dustin@cumulusnetworks.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-25 15:49:46 +01:00
Jarkko Nikula
dd77f423e5 i2c: i801: Add support for Intel Broxton
This patch adds the SMBUS PCI ID of Intel Broxton.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-23 22:11:58 +02:00
Mika Westerberg
84d7f2ebd7 i2c: i801: Add support for Intel DNV
Intel DNV SoC has the same legacy SMBus host controller than Intel
Sunrisepoint PCH. It also has same iTCO watchdog on the bus.

Add DNV PCI ID to the list of supported devices.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-23 22:10:31 +02:00
Mika Westerberg
9424693035 i2c: i801: Create iTCO device on newer Intel PCHs
Starting from Intel Sunrisepoint (Skylake PCH) the iTCO watchdog resources
have been moved to reside under the i801 SMBus host controller whereas
previously they were under the LPC device.

In order to support the iTCO watchdog on newer PCHs we need to create the
platform device here in the SMBus driver and pass all known resources using
platform data.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-11 15:03:51 +01:00
Jarkko Nikula
fef220da43 i2c: i801: Use managed pcim_* PCI device initialization and reservation
Simplifies the code a bit and makes easier to disable PCI device on driver
detach by removing the pcim_pin_device() call in the future if needed.

Reason why i2c-i801.c doesn't ever call pci_disable_device() was because it
made some systems to hang during power-off. See commit d6fcb3b9cf
("[PATCH] i2c-i801.c: don't pci_disable_device() after it was just enabled")
and
http://marc.info/?l=linux-kernel&m=115160053309535&w=2

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-09 10:51:59 +01:00
Jarkko Nikula
f85da3f5de i2c: i801: Remove pci_enable_device() call from i801_resume()
Since pci_disable_device() is not called from i801_suspend() and power
state is set already it means that subsequent pci_enable_device() calls do
practically nothing but monotonically increase struct pci_dev enable_cnt.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-09 10:51:59 +01:00
Jarkko Nikula
1621c59d94 i2c: i801: Use managed devm_* memory and irq allocation
This simplifies the error and remove paths.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-09 10:51:59 +01:00
Jarkko Nikula
256493c586 i2c: i801: Remove i801_driver forward declaration
struct pci_driver i801_driver forward declaration is needed only for
accessing the name field. Remove it and use dev_driver_string() instead.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-09 10:51:58 +01:00
Jarkko Nikula
9cbbf3dc99 i2c: i801: Don't break user-visible strings
It makes more difficult to grep these error prints from sources if they are
split to multiple source lines.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-09 10:51:58 +01:00
Devin Ryles
3eee1799ae i2c: i801: Add DeviceIDs for SunrisePoint LP
Signed-off-by: Devin Ryles <devin.ryles@intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-12 17:19:13 +01:00
Jean Delvare
550d0407a8 i2c: i801: Drop useless debug message
Don't log the host status register value in i801_isr(), it has very
little value and fills up the log when debugging is enabled.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-12 16:26:49 +01:00
Jean Delvare
aeb8a3d16a i2c: i801: Check if interrupts are disabled
There is a control bit in the PCI configuration space which disables
interrupts. If this bit is set, the driver should not try to make use
of interrupts, it won't receive any.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-12 16:26:41 +01:00
Jean Delvare
ae94471717 i2c: i801: Fallback to polling if request_irq() fails
The i2c-i801 driver can work without interrupts, so there is no reason
to make a request_irq failure fatal. Instead we can simply fallback
to polling.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-12 16:26:32 +01:00
Jean Delvare
b3b8df9772 i2c: i801: Use wait_event_timeout to wait for interrupts
Some systems have been reported to have trouble with interrupts. Use
wait_event_timeout() instead of wait_event() so we don't get stuck in
that case, and log the problem.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-12 16:06:38 +01:00
Wolfram Sang
ca1f8da9ac i2c: remove FSF address
We have a central copy of the GPL for that. Some addresses were already
outdated.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2014-11-07 18:35:33 +01:00
james.d.ralston@intel.com
3e27a8445c i2c: i801: Add Device IDs for Intel Sunrise Point PCH
This patch adds the I2C/SMBus Device IDs for the Intel Sunrise Point PCH.

Signed-off-by: James Ralston <james.d.ralston@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-16 09:16:22 +02:00
Alan Cox
39e8e30ee5 i2c: i801: Add PCI ID for Intel Braswell
The SMBus host controller is the same as used in Baytrail so add the new
PCI ID to the driver's list of supported IDs.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-19 10:19:47 -05:00
Jean Delvare
b299de8391 i2c: i801: Add device ID for Intel Wildcat Point PCH
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-07-17 19:56:23 +02:00
Jean Delvare
ce3161106a i2c: i801: Fix the alignment of the device table
A long name broke the alignment, shift the columns a bit to fix it and
make the table look nice again. While we're here, switch to the
standard comment style to make checkpatch happy, and use tabs instead
of spaces for column alignment.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-07-17 19:56:19 +02:00
Jingoo Han
392debf116 i2c: remove DEFINE_PCI_DEVICE_TABLE macro
Don't use DEFINE_PCI_DEVICE_TABLE macro, because this macro
is not preferred.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-13 09:44:59 +01:00
Chew, Kean ho
1b31e9b76e i2c: i801: enable Intel BayTrail SMBUS
Add Device ID of Intel BayTrail SMBus Controller.

Signed-off-by: Chew, Kean ho <kean.ho.chew@intel.com>
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-09 21:40:25 +01:00
Jean Delvare
7c81c60f37 Update Jean Delvare's e-mail address
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2014-01-29 20:40:08 +01:00
James Ralston
afc6592412 i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH
This patch adds the SMBus Device IDs for the Intel Wildcat Point-LP PCH.

Signed-off-by: James Ralston <james.d.ralston@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-11-14 18:38:04 +01:00
Wolfram Sang
687b81d083 i2c: move OF helpers into the core
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23 10:22:20 +02:00
Seth Heasley
f39901c1be i2c: i801: SMBus patch for Intel Coleto Creek DeviceIDs
This patch adds the i801 SMBus Controller DeviceIDs for the Intel Coleto Creek PCH.

Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-20 21:32:27 +02:00
Jean Delvare
5322934550 i2c: i801: Document feature bits in modinfo
Duplicate the feature bits documentation in modinfo, as not every user
will read the driver's source code or documentation file.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17 22:49:30 +02:00
Doug Anderson
55827f4aa6 i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls
There is simply no reason to be manually setting the private driver
data to NULL in the remove/fail to probe cases.  This is just extra
cruft code that can be removed.

A few notes:
* Nothing relies on drvdata being set to NULL.
* The __device_release_driver() function eventually calls
  dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
  twice.
* I verified that there were no cases where xxx_get_drvdata() was
  being called in these drivers and checking for / relying on the NULL
  return value.

This could be cleaned up kernel-wide but for now just take the baby
step and remove from the i2c subsystem.

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
2013-02-22 00:25:50 +01:00
James Ralston
a3fc0ff00a i2c: i801: Add Device IDs for Intel Wellsburg PCH
This patch adds the SMBus Device IDs for the Intel Wellsburg PCH

Signed-off-by: James Ralston <james.d.ralston@intel.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
2013-02-15 20:46:01 +01:00
Seth Heasley
c2db409cbc i2c: i801: SMBus patch for Intel Avoton DeviceIDs
This patch adds the PCU SMBus DeviceID for the Intel Avoton SOC.

Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2013-02-08 20:06:29 +01:00
Bill Pemberton
0b255e927d i2c: remove __dev* attributes from subsystem
CONFIG_HOTPLUG is going away as an option.  As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-12-22 20:13:45 +01:00
Jean Delvare
6676a847d4 i2c-i801: Enable interrupts for all post-ICH5 chips
I did not receive a single bug report after interrupt support was
added for a limited number of chips. So I'd say the code is good and
should be enabled for all supported chips, that is: ICH5 and later.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
2012-12-16 21:11:55 +01:00
Thierry Reding
f6afc8b158 i2c-i801: Add device tree support
Add support for probing slave devices parsed from the device tree.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-12-16 21:11:54 +01:00
Jean Delvare
28901f5794 i2c-i801: Fix comment
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-28 21:37:01 +01:00
Jean Delvare
79e3e5b894 i2c-i801: Simplify dependency towards GPIOLIB
Arbitrarily selecting GPIOLIB causes trouble on some architectures,
so don't do that. Instead, just make the optional multiplexing code
depend on CONFIG_I2C_MUX_GPIO instead of CONFIG_I2C_MUX for now. We
can revisit if the i2c-i801 driver ever supports other multiplexing
flavors.

Also make that optional code depend on DMI, as it won't do anything
without that.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
2012-10-28 21:37:01 +01:00
Jean Delvare
f82b86267a i2c-i801: Let i2c-mux-gpio find the GPIO chip
Now that i2c-mux-gpio is able to find the GPIO chip by itself, we can
delegate this task. The great thing here is that i2c-mux-gpio can
defer device probing until the gpio chip is available, so we no longer
depend on the module loading order.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-05 22:23:54 +02:00
Jean Delvare
3ad7ea18ae i2c-i801: Support SMBus multiplexing on Asus Z8 series
Add support for SMBus multiplexing on Asus Z8 motherboard series. On
these boards, the memory slots are behind a GPIO-controlled I2C
multiplexer. Models with 6 or 12 memory slots have 2 segments behind
the multiplexer, while models with 18 memory slots have 3 such
segments.

On these boards, only the memory slots are behind the multiplexer,
so it is possible to keep the autodetection mechanism.

The code is generic enough so it could work on other boards as long as
the multiplexer is controlled by GPIO pins. For other forms of
multiplexing (for example using an I2C device) additional code will be
needed.

Thanks to Asus for providing a board to develop and test this feature,
as well as all the technical information required.

At the moment, the GPIO driver must be loaded before the i2c-i801
driver, but I hope to solve this soon, using deferred probing on
the i2c-mux-gpio side.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-05 22:23:53 +02:00