Commit graph

13 commits

Author SHA1 Message Date
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
Stephen Barber
d365407079 mfd: cros_ec: add bus-specific proto v3 code
Add proto v3 support to the SPI, I2C, and LPC.

Signed-off-by: Stephen Barber <smbarber@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
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 13:18:22 +01:00
Stephen Barber
2c7589af3c mfd: cros_ec: add proto v3 skeleton
Add support in cros_ec.c to handle EC host command protocol v3.
For v3+, probe for maximum shared protocol version and max
request, response, and passthrough sizes. For now, this will
always fall back to v2, since there is no bus-specific code
for handling proto v3 packets.

Signed-off-by: Stephen Barber <smbarber@chromium.org>
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>
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 13:18:21 +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
Gwendal Grignou
e7b707f968 mfd: cros_ec: Remove parent field
Parent and device were pointing to the same device structure.

Parent is unused, removed.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Stephen Barber <smbarber@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Puthikorn Voravootivat <puthik@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-06-15 13:18:17 +01:00
Doug Anderson
d6c15ed2bc mfd: cros_ec: Use the proper size when looking at the cros_ec_i2c result
We know how many bytes the EC should be sending us (which is also the
number of bytes transferred) and also how many bytes the EC actually
wanted to send to us.  When computing the checksum and copying back
data let's make sure we take the lesser of the two of those.  We'll
also complain if the EC tried to send us too many bytes.  The EC
sending us too few bytes is legit for when we send the EC an invalid
command.

This is based on similar code in cros_ec_spi.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 16:38:21 +01:00
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
6db07b6336 mfd: cros_ec: Check result code from EC messages
Just because the host was able to talk to the EC doesn't mean that the EC
was happy with what it was told. Errors in communincation are not the same
as error messages from the EC itself.

This change lets the EC report its errors separately.

[dianders: Added common function to cros_ec.c]

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 14:58:19 +01:00
Bill Richardson
533cec8f34 mfd: cros_ec: cleanup: remove unused fields from struct cros_ec_device
struct cros_ec_device has a superfluous "name" field. We can get all the
debugging info we need from the existing ec_name and phys_name fields, so
let's take out the extra field.

The printout also has sufficient info in it without explicitly adding
the transport.  Before this change:
  cros-ec-spi spi2.0: Chrome EC (SPI)

After this change:
  cros-ec-spi spi2.0: Chrome EC device registered

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 14:58:18 +01:00
Bill Richardson
5d4773e27e mfd: cros_ec: Use struct cros_ec_command to communicate with the EC
This is some internal structure reorganization / renaming to prepare
for future patches that will add a userspace API to cros_ec.  There
should be no visible changes.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 14:58:17 +01:00
Bill Richardson
7e6cb5b4db mfd: cros_ec: Tweak struct cros_ec_device for clarity
The members of struct cros_ec_device were improperly commented, and
intermixed the private and public sections. This is just cleanup to make it
more obvious what goes with what.

[dianders: left lock in the structure but gave it the name that will
eventually be used.]

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-07-09 14:58:16 +01:00
Thierry Reding
192afe5e16 mfd: cros ec: i2c: Use consistent function names
Rename cros_ec_{probe,remove}_i2c() to cros_ec_i2c_{probe,remove}() for
consistency.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-21 08:13:35 +00:00
Simon Glass
8996900948 mfd: Add ChromeOS EC I2C driver
This uses an I2C bus to talk to the ChromeOS EC. The protocol
is defined by the EC and is fairly simple, with a length byte,
checksum, command byte and version byte (to permit easy creation
of new commands).

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-04-05 11:20:13 +02:00