linux-toradex.git/drivers/mfd/cros_ec.c, branch v4.4.64

mfd: cros_ec: Staticise some newly introduced structures

2015-06-22T11:23:02+00:00

Signed-off-by: Lee Jones

mfd: cros_ec: Support multiple EC in a system

2015-06-15T12:18:23+00:00

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 
Reviewed-by: Dmitry Torokhov 
Signed-off-by: Javier Martinez Canillas 
Tested-by: Heiko Stuebner 
Acked-by: Lee Jones 
Acked-by: Olof Johansson 
Signed-off-by: Lee Jones

mfd: cros_ec: add proto v3 skeleton

2015-06-15T12:18:21+00:00

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 
Signed-off-by: Javier Martinez Canillas 
Reviewed-by: Gwendal Grignou 
Tested-by: Gwendal Grignou 
Tested-by: Heiko Stuebner 
Acked-by: Lee Jones 
Acked-by: Olof Johansson 
Signed-off-by: Lee Jones

mfd: cros_ec: Move protocol helpers out of the MFD driver

2015-06-15T12:18:20+00:00

The MFD driver should only have the logic to instantiate its child devices
and setup any shared resources that will be used by the subdevices drivers.

The cros_ec MFD is more complex than expected since it also has helpers to
communicate with the EC. So the driver will only get more bigger as other
protocols are supported in the future. So move the communication protocol
helpers to its own driver as drivers/platform/chrome/cros_ec_proto.c.

Suggested-by: Lee Jones 
Signed-off-by: Javier Martinez Canillas 
Tested-by: Heiko Stuebner 
Acked-by: Lee Jones 
Acked-by: Olof Johansson 
Signed-off-by: Lee Jones

mfd: cros_ec: Use a zero-length array for command data

2015-06-15T12:18:19+00:00

Commit 1b84f2a4cd4a ("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 
Signed-off-by: Javier Martinez Canillas 
Tested-by: Heiko Stuebner 
Acked-by: Lee Jones 
Acked-by: Olof Johansson 
Signed-off-by: Lee Jones

mfd: cros_ec: Instantiate sub-devices from device tree

2015-06-15T12:18:18+00:00

If the EC device tree node has sub-nodes, try to instantiate them as
MFD sub-devices.  We can configure the EC features provided by the board.

Signed-off-by: Todd Broch 
Signed-off-by: Javier Martinez Canillas 
Reviewed-by: Gwendal Grignou 
Tested-by: Heiko Stuebner 
Signed-off-by: Lee Jones

mfd: cros_ec: Instantiate ChromeOS EC character device

2015-02-26T23:45:09+00:00

The ChromeOS EC character device is an user-space interface to
allow applications to access the Embedded Controller.

Add a cell for this device so it's spawned from the mfd driver.

Signed-off-by: Javier Martinez Canillas 
Acked-by: Lee Jones 
Tested-by: Gwendal Grignou 
Reviewed-by: Gwendal Grignou 
Signed-off-by: Olof Johansson

mfd: cros_ec: Use fixed size arrays to transfer data with the EC

2015-02-26T23:44:52+00:00

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 
Acked-by: Lee Jones 
Tested-by: Gwendal Grignou 
Reviewed-by: Gwendal Grignou 
Signed-off-by: Olof Johansson

mfd: cros_ec: wait for completion of commands that return IN_PROGRESS

2014-10-06T20:30:16+00:00

When an EC command returns EC_RES_IN_PROGRESS, we need to query
the state of the EC until it indicates that it is no longer busy.
Do this in cros_ec_cmd_xfer() under the EC's mutex so that other
commands (e.g. keyboard, I2C passtru) aren't issued to the EC while
it is working on the in-progress command.

The 10 milliseconds delay and the number of retries are the values
that were used by the flashrom tool when retrying commands.

Signed-off-by: Andrew Bresticker 
Reviewed-by: Simon Glass 
Signed-off-by: Javier Martinez Canillas 
Signed-off-by: Lee Jones

mfd: cros_ec: move locking into cros_ec_cmd_xfer

2014-10-06T20:29:50+00:00

Now that there's a central cros_ec_cmd_xfer(), move the locking
out of the SPI driver.

Signed-off-by: Andrew Bresticker 
Reviewed-by: Simon Glass 
Signed-off-by: Javier Martinez Canillas 
Reviewed-by: Doug Anderson 
Signed-off-by: Lee Jones