Commit Graph

13 Commits

Author SHA1 Message Date
Enric Balletbo i Serra 5668bfdd90 platform/chrome: cros_ec_dev - Register cros-ec sensors
Check whether the ChromeOS Embedded Controller is a sensor hub and in
such case issue a command to get the number of sensors and register them
all.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-10-25 18:20:32 +01:00
Vincent Palatin e4244ebdda platform/chrome: Introduce a new function to check EC features.
Use the EC_CMD_GET_FEATURES message to check the supported features for
each MCU.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
[tomeu: adapted to changes in mainline]
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
[enric: remove references to USB PD feature and do it more generic]
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
For the MFD changes:
  Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-10-25 18:20:29 +01:00
Dan Carpenter 096cdc6f52 platform/chrome: cros_ec_dev - double fetch bug in ioctl
We verify "u_cmd.outsize" and "u_cmd.insize" but we need to make sure
that those values have not changed between the two copy_from_user()
calls.  Otherwise it could lead to a buffer overflow.

Additionally, cros_ec_cmd_xfer() can set s_cmd->insize to a lower value.
We should use the new smaller value so we don't copy too much data to
the user.

Reported-by: Pengfei Wang <wpengfeinudt@gmail.com>
Fixes: a841178445 ('mfd: cros_ec: Use a zero-length array for command data')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Cc: <stable@vger.kernel.org> # v4.2+
Signed-off-by: Olof Johansson <olof@lixom.net>
2016-07-05 14:01:52 -07:00
Guenter Roeck 2521ea3e0d platform/chrome: cros_ec_dev - Populate compat_ioctl
compat_ioctl has to be populated for 32 bit userspace applications to work
with 64 bit kernels.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2016-05-11 11:55:48 -07:00
Gwendal Grignou 5d749d0bbe platform/chrome: cros_ec_dev - Fix security issue
Prevent memory scribble by checking that ioctl buffer size parameters
are sane.
Without this check, on 32 bits system, if .insize = 0xffffffff - 20 and
.outsize the amount to scribble, we would overflow, allocate a small
amounts and be able to write outside of the malloc'ed area.
Adding a hard limit allows argument checking of the ioctl. With the
current EC, it is expected .insize and .outsize to be at around 512 bytes
or less.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2016-05-11 11:55:47 -07:00
Emilio López 18800fc7a0 platform/chrome: Support reading/writing the vboot context
Some EC implementations include a small nvram space used to store
verified boot context data. This patch offers a way to expose this
data to userspace.

Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Emilio López <emilio.lopez@collabora.co.uk>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-10-07 15:05:53 -07:00
Javier Martinez Canillas afbf8ec7c4 platform/chrome: cros_ec_dev - Add a platform device ID table
If the cros_ec_dev driver is built as a module, modalias information is
not filled so the module is not autoloaded. Add a platform device table
and use the MODULE_DEVICE_TABLE() macro to export that information in
the module so user-space can match the modalias uevent and autoload it.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-10-07 14:34:26 -07:00
Gwendal Grignou 57b33ff077 mfd: cros_ec: Support multiple EC in a system
Chromebooks can have more than one Embedded Controller so the
cros_ec device id has to be incremented for each EC registered.

Add a new structure to represent multiple EC as different char
devices (e.g: /dev/cros_ec, /dev/cros_pd). It connects to
cros_ec_device and allows sysfs inferface for cros_pd.

Also reduce number of allocated objects, make chromeos sysfs
class object a static and add refcounting to prevent object
deletion while command is in progress.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Dmitry Torokhov <dtor@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 13:18:23 +01:00
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
Olof Johansson ef59c25d1b platform/chrome: cros_ec_dev - fix Unknown escape '%' warning
Fix the following sparse warning:

    drivers/platform/chrome/cros_ec_dev.c:64:45: sparse: Unknown escape '%'

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Olof Johansson <olofj@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-03-04 11:23:10 -08:00
Bill Richardson f3f837e52b platform/chrome: Expose Chrome OS Lightbar to users
This adds some sysfs entries to provide userspace control of the
four-element LED "lightbar" on the Chromebook Pixel. This only instantiates
the lightbar controls if the device actually exists.

To prevent DoS attacks, this interface is limited to 20 accesses/second,
although that rate can be adjusted by a privileged user.

On Chromebooks without a lightbar, this should have no effect. On the
Chromebook Pixel, you should be able to do things like this:

    $ cd /sys/devices/virtual/chromeos/cros_ec/lightbar
    $ echo 0x80 > brightness
    $ echo 255 > brightness
    $
    $ cat sequence
    S0
    $ echo konami > sequence
    $ cat sequence
    KONAMI
    $
    $ cat sequence
    S0

And

    $ cd /sys/devices/virtual/chromeos/cros_ec/lightbar
    $ echo stop > sequence
    $ echo "4 255 255 255" > led_rgb
    $ echo "0 255 0 0  1 0 255 0  2 0 0 255  3 255 255 0" > led_rgb
    $ echo run  > sequence

Test the DoS prevention with this:

    $ cd /sys/devices/virtual/chromeos/cros_ec/lightbar
    $ echo 500 > interval_msec
    $ time (cat version version version version version version version)

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
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 15:45:16 -08:00
Bill Richardson 71af4b52cc platform/chrome: Create sysfs attributes for the ChromeOS EC
This adds the first few sysfs attributes for the Chrome OS EC. These
controls are made available under /sys/devices/virtual/chromeos/cros_ec

    flashinfo   - display current flash info
    reboot      - tell the EC to reboot in various ways
    version     - information about the EC software and hardware

Future changes will build on this to add additional controls.

From a root shell, you should be able to do things like this:

    cd /sys/devices/virtual/chromeos/cros_ec
    cat flashinfo
    cat version
    echo rw > reboot
    cat version
    echo ro > reboot
    cat version
    echo rw > reboot
    cat version
    echo cold > reboot

That last command will reboot the AP too.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
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 15:45:12 -08:00
Bill Richardson e7c256fbfb platform/chrome: Add Chrome OS EC userspace device interface
This patch adds a device interface to access the
Chrome OS Embedded Controller from user-space.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Simon Glass <sjg@google.com>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Gwendal Grignou <gwendal@chromium.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 15:45:06 -08:00