Commit Graph

18 Commits

Author SHA1 Message Date
Raul E Rangel
b49f8e0e7b i2c: cros-ec-tunnel: Fix ACPI identifier
The initial patch was using the incorrect identifier.

Fixes: 9af1563a54 ("i2c: cros-ec-tunnel: Make the device acpi compatible")
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-31 09:01:25 +01:00
Akshu Agrawal
8ff2d7ca4a i2c: cros-ec-tunnel: Fix slave device enumeration
During adding of the adapter the slave device registration
use to fail as the acpi companion field was not populated.

Fixes: 9af1563a54 ("i2c: cros-ec-tunnel: Make the device acpi compatible")
Signed-off-by: Akshu Agrawal <akshu.agrawal@amd.com>
Acked-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-31 09:01:20 +01:00
Akshu Agrawal
9af1563a54 i2c: cros-ec-tunnel: Make the device acpi compatible
Add ACPI entry and use device_property_read to get fw value
which is common to both dtsi and acpi.

Signed-off-by: Akshu Agrawal <akshu.agrawal@amd.com>
Acked-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-11-11 21:38:03 +01:00
Enric Balletbo i Serra
840d9f131f mfd / platform: cros_ec: Reorganize platform and mfd includes
There is a bit of mess between cros-ec mfd includes and platform
includes. For example, we have a linux/mfd/cros_ec.h include that
exports the interface implemented in platform/chrome/cros_ec_proto.c. Or
we have a linux/mfd/cros_ec_commands.h file that is non related to the
multifunction device (in the sense that is not exporting any function of
the mfd device). This causes crossed includes between mfd and
platform/chrome subsystems and makes the code difficult to read, apart
from creating 'curious' situations where a platform/chrome driver includes
a linux/mfd/cros_ec.h file just to get the exported functions that are
implemented in another platform/chrome driver.

In order to have a better separation on what the cros-ec multifunction
driver does and what the cros-ec core provides move and rework the
affected includes doing:

 - Move cros_ec_commands.h to include/linux/platform_data/cros_ec_commands.h
 - Get rid of the parts that are implemented in the platform/chrome/cros_ec_proto.c
   driver from include/linux/mfd/cros_ec.h to a new file
   include/linux/platform_data/cros_ec_proto.h
 - Update all the drivers with the new includes, so
   - Drivers that only need to know about the protocol include
     - linux/platform_data/cros_ec_proto.h
     - linux/platform_data/cros_ec_commands.h
   - Drivers that need to know about the cros-ec mfd device also include
     - linux/mfd/cros_ec.h

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Series changes: 3
- Fix dereferencing pointer to incomplete type 'struct cros_ec_dev' (lkp)
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-09-02 11:33:42 +01:00
Enric Balletbo i Serra
02d26b9a57 i2c: i2c-cros-ec-tunnel: Switch to SPDX identifier.
Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-12-17 23:08:41 +01:00
Guenter Roeck
22ae11245e i2c: i2c-cros-ec-tunnel: Reduce logging noise
If an i2c access through i2c-cros-ec-tunnel returns an error, the following
log message is seen on the console.

cros-ec-i2c-tunnel ff200000.spi:ec@0:i2c-tunnel:
			Error parsing EC i2c message -121

This can happen a lot if, for example, the i2c-detect command is executed.

Since it is perfectly normal for an i2c controller to report an error,
drop the message. Also, report -ENXIO instead of -EREMOTEIO if the access
error is due to NAK from the device, and return -EIO instead of -EREMOTEIO
for other errors, as suggested in Documentation/i2c/fault-codes.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-01-28 22:16:38 +01:00
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
Brian Norris
4d01d88019 i2c: cros-ec-tunnel: Fix usage of cros_ec_cmd_xfer()
cros_ec_cmd_xfer returns success status if the command transport
completes successfully, but the execution result is incorrectly ignored.
In many cases, the execution result is assumed to be successful, leading
to ignored errors and operating on uninitialized data.

We've recently introduced the cros_ec_cmd_xfer_status() helper to avoid these
problems. Let's use it.

[Regarding the 'Fixes' tag; there is significant refactoring since the driver's
introduction, but the underlying logical error exists throughout I believe]

Fixes: 9d230c9e4f ("i2c: ChromeOS EC tunnel driver")
Cc: <stable@vger.kernel.org> # 9798ac6d32 mfd: cros_ec: Add cros_ec_cmd_xfer_status() helper
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-15 00:55:14 +02:00
Javier Martinez Canillas
a841178445 mfd: cros_ec: Use a zero-length array for command data
Commit 1b84f2a4cd ("mfd: cros_ec: Use fixed size arrays to transfer
data with the EC") modified the struct cros_ec_command fields to not
use pointers for the input and output buffers and use fixed length
arrays instead.

This change was made because the cros_ec ioctl API uses that struct
cros_ec_command to allow user-space to send commands to the EC and
to get data from the EC. So using pointers made the API not 64-bit
safe. Unfortunately this approach was not flexible enough for all
the use-cases since there may be a need to send larger commands
on newer versions of the EC command protocol.

So to avoid to choose a constant length that it may be too big for
most commands and thus wasting memory and CPU cycles on copy from
and to user-space or having a size that is too small for some big
commands, use a zero-length array that is both 64-bit safe and
flexible. The same buffer is used for both output and input data
so the maximum of these values should be used to allocate it.

Suggested-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-06-15 13:18:19 +01:00
Javier Martinez Canillas
1b84f2a4cd mfd: cros_ec: Use fixed size arrays to transfer data with the EC
The struct cros_ec_command will be used as an ioctl() argument for the
API to control the ChromeOS EC from user-space. So the data structure
has to be 64-bit safe to make it compatible between 32 and 64 avoiding
the need for a compat ioctl interface. Since pointers are self-aligned
to different byte boundaries, use fixed size arrays instead of pointers
for transferring ingoing and outgoing data with the Embedded Controller.

Also, re-arrange struct members by decreasing alignment requirements to
reduce the needing padding size.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-02-26 15:44:52 -08:00
Linus Torvalds
278f1d0730 Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Highlights from the I2C subsystem for 3.18:

   - new drivers for Axxia AM55xx, and Hisilicon hix5hd2 SoC.

   - designware driver gained AMD support, exynos gained exynos7 support

  The rest is usual driver stuff.  Hopefully no lowlights this time"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: i801: Add Device IDs for Intel Sunrise Point PCH
  i2c: hix5hd2: add i2c controller driver
  i2c-imx: Disable the clock on probe failure
  i2c: designware: Add support for AMD I2C controller
  i2c: designware: Rework probe() to get clock a bit later
  i2c: designware: Default to fast mode in case of ACPI
  i2c: axxia: Add I2C driver for AXM55xx
  i2c: exynos: add support for HSI2C module on Exynos7
  i2c: mxs: detect No Slave Ack on SELECT in PIO mode
  i2c: cros_ec: Remove EC_I2C_FLAG_10BIT
  i2c: cros-ec-tunnel: Add of match table
  i2c: rcar: remove sign-compare flaw
  i2c: ismt: Use minimum descriptor size
  i2c: imx: Add arbitration lost check
  i2c: rk3x: Remove unlikely() annotations
  i2c: rcar: check for no IRQ in rcar_i2c_irq()
  i2c: rcar: make rcar_i2c_prepare_msg() *void*
  i2c: rcar: simplify check for last message
  i2c: designware: add support of platform data to set I2C mode
  i2c: designware: add support of I2C standard mode
2014-10-19 12:50:44 -07:00
Derek Basehore
9772070608 i2c: i2c-cros-ec-tunnel: Set retries to 3
Since the i2c bus can get wedged on the EC sometimes, set the number of retries
to 3. Since we un-wedge the bus immediately after the wedge happens, this is the
correct fix since only one transfer will fail.

Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-10-06 21:30:04 +01:00
Andrew Bresticker
a6551a76ff mfd: cros_ec: stop calling ->cmd_xfer() directly
Instead of having users of the ChromeOS EC call the interface-specific
cmd_xfer() callback directly, introduce a central cros_ec_cmd_xfer()
to use instead.  This will allow us to put all the locking and retry
logic in one place instead of duplicating it across the different
drivers.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-10-06 21:29:07 +01:00
Doug Anderson
d8e0a86f97 i2c: cros_ec: Remove EC_I2C_FLAG_10BIT
In <https://lkml.org/lkml/2014/6/10/265> pointed out that the 10-bit
flag in the cros_ec_tunnel was useless.  It went into a 16-bit flags
field but was defined at (1 << 16).

Since we have no 10-bit i2c devices on the other side of the tunnel on
any known devices this was never a problem.  Until we do it makes
sense to remove this code.  On the EC side the code to handle this
flag was removed in <https://chromium-review.googlesource.com/204162>.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-30 08:06:02 +02:00
Sjoerd Simons
6c97c9c1ac i2c: cros-ec-tunnel: Add of match table
To enable the cros-ec-tunnel driver to be auto-loaded when build as a
module add an of match table (and export it) to match the modalias
information passed on to userspace as the Cros EC MFD driver registers
the MFD subdevices with an of_compatibility string.

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:52:16 +02:00
Bill Richardson
12ebc8a50b mfd: cros_ec: ec_dev->cmd_xfer() returns number of bytes received from EC
When communicating with the EC, the cmd_xfer() function should return the
number of bytes it received from the EC, or negative on error.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 14:58:20 +01:00
Bill Richardson
5799f95a37 mfd: cros_ec: cleanup: Remove EC wrapper functions
Remove the three wrapper functions that talk to the EC without passing all
the desired arguments and just use the underlying communication function
that passes everything in a struct intead.

This is internal code refactoring only. Nothing should change.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 14:58:18 +01:00
Doug Anderson
9d230c9e4f i2c: ChromeOS EC tunnel driver
On ARM Chromebooks we have a few devices that are accessed by both the
AP (the main "Application Processor") and the EC (the Embedded
Controller).  These are:
* The battery (sbs-battery).
* The power management unit tps65090.

On the original Samsung ARM Chromebook these devices were on an I2C
bus that was shared between the AP and the EC and arbitrated using
some extranal GPIOs (see i2c-arb-gpio-challenge).

The original arbitration scheme worked well enough but had some
downsides:
* It was nonstandard (not using standard I2C multimaster)
* It only worked if the EC-AP communication was I2C
* It was relatively hard to debug problems (hard to tell if i2c issues
  were caused by the EC, the AP, or some device on the bus).

On the HP Chromebook 11 the design was changed to:
* The AP/EC comms were still i2c, but the battery/tps65090 were no
  longer on the bus used for AP/EC communication.  The battery was
  exposed to the AP through a limited i2c tunnel and tps65090 was
  exposed to the AP through a custom Linux driver.

On the Samsung ARM Chromebook 2 the scheme is changed yet again, now:
* The AP/EC comms are now using SPI for faster speeds.
* The EC's i2c bus is exposed to the AP through a full i2c tunnel.

The upstream "tegra124-venice2" uses the same scheme as the Samsung
ARM Chromebook 2, though it has a different set of components on the
other side of the bus.

This driver supports the scheme used by the Samsung ARM Chromebook 2.
Future patches to this driver could add support for the battery tunnel
on the HP Chromebook 11 (and perhaps could even be used to access
tps65090 on the HP Chromebook 11 instead of using a special driver,
but I haven't researched that enough).

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-03 08:11:49 +01:00