Commit Graph

13 Commits

Author SHA1 Message Date
Doug Anderson
9c0b54a120 mfd: cros_ec: spi: Increase cros_ec_spi deadline from 5ms to 100ms
We're adding i2c tunneling to the list of things that goes over
cros_ec.  i2c tunneling can be slooooooow, so increase our deadline to
100ms to account for that.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Andrew Bresticker <abrestic@chromium.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-03 08:11:48 +01:00
Doug Anderson
c9a81d67ce mfd: cros_ec: spi: Make the cros_ec_spi timeout more reliable
The cros_ec_spi transfer had two problems with its timeout code:

1. It looked at the timeout even in the case that it found valid data.
2. If the cros_ec_spi code got switched out for a while, it's possible
   it could get a timeout after a single loop.  Let's be paranoid and
   make sure we do one last transfer after the timeout expires.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Andrew Bresticker <abrestic@chromium.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-03 08:11:47 +01:00
Doug Anderson
362196e5d0 mfd: cros_ec: spi: Add mutex to cros_ec_spi
The main transfer function for cros_ec_spi can be called by more than
one client at a time.  Make sure that those clients don't stomp on
each other by locking the bus for the duration of the transfer
function.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Andrew Bresticker <abrestic@chromium.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-03 08:11:46 +01:00
David Hendricks
1fe368665b mfd: cros_ec: spi: Calculate delay between transfers correctly
To avoid spamming the EC we calculate the time between the previous
transfer and the current transfer and force a delay if the time delta
is too small.

However, a small miscalculation causes the delay period to be
far too short. Most noticably this impacts commands with a long
turnaround time such as EC firmware reads and writes.

Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Andrew Bresticker <abrestic@chromium.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-03 08:11:46 +01:00
Rhyland Klein
01e73c89cf mfd: cros ec: spi: Add delay for raising CS
The EC has specific timing it requires. Add support for an optional delay
after raising CS to fix timing issues. This is configurable based on
a DT property "google,cros-ec-spi-msg-delay".

If this property isn't set, then no delay will be added. However, if set
it will cause a delay equal to the value passed to it to be inserted at
the end of a transaction.

Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Reviewed-by: Bernie Thompson <bhthompson@chromium.org>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-21 08:28:06 +00:00
Thierry Reding
daf93d2287 mfd: cros ec: spi: Use 0 instead of '\0' consistently
memset() was being called with the second parameter set to '\0', which
is equivalent but longer than the more canonical 0. Update the code to
use the latter variant consistently across the driver.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-21 08:28:05 +00:00
Thierry Reding
ea0f8b0b67 mfd: cros ec: spi: Use correct module license
According to the header comment in the source file the driver is
licensed under GPL v2, so update MODULE_LICENSE() to match that.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-21 08:28:04 +00:00
Thierry Reding
9922b4129c mfd: cros ec: spi: Use consistent function names
Rename cros_ec_{probe,remove}_spi() to cros_ec_spi_{probe,remove}() for
consistency.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-21 08:13:34 +00:00
Thierry Reding
9e146f4330 mfd: cros ec: spi: Fix debug output
The dev_cont() symbol doesn't exist, so replace it with pr_cont(). While
at it, also append a newline to the debug output to make it look nicer.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-06 09:13:23 +00:00
Derek Basehore
49f91ac331 mfd: cros ec: spi: Increase EC transaction delay
50 us is not a long enough delay between EC transactions. At least 70 us
are needed for the 16 MHz STM32L part. Increase the delay to 200 us for
an extra safety margin.

Reviewed-by: Randall Spangler <rspangler@chromium.org>
Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-01-06 09:13:23 +00:00
Geert Uytterhoeven
c34924b950 mfd: cros_ec_spi: Use %z to format pointer differences
Before commit 5c29e47e6a ("mfd: cros_ec_spi:
Warnings fix"), 64-bit compiles gave the following warnings:

drivers/mfd/cros_ec_spi.c: In function 'cros_ec_spi_receive_response':
drivers/mfd/cros_ec_spi.c:123:5: warning: format '%d' expects argument of type 'int', but argument 4 has type 'long int' [-Wformat]
drivers/mfd/cros_ec_spi.c:157:3: warning: format '%d' expects argument of type 'int', but argument 6 has type 'long int' [-Wformat]
drivers/mfd/cros_ec_spi.c:181:2: warning: format '%d' expects argument of type 'int', but argument 4 has type 'long int' [-Wformat]

After that commit, 32-bit compiles give:

drivers/mfd/cros_ec_spi.c: In function ‘cros_ec_spi_receive_response’:
drivers/mfd/cros_ec_spi.c:123: warning: format ‘%ld’ expects type ‘long int’, but argument 4 has type ‘int’
drivers/mfd/cros_ec_spi.c:157: warning: format ‘%ld’ expects type ‘long int’, but argument 6 has type ‘int’
drivers/mfd/cros_ec_spi.c:181: warning: format ‘%ld’ expects type ‘long int’, but argument 4 has type ‘int’

Use %z to format pointer differences to kill the warnings on both 32-bit
and 64-bit.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-05-16 19:14:06 +02:00
Samuel Ortiz
5c29e47e6a mfd: cros_ec_spi: Warnings fix
To silent those:

 CC [M]  drivers/mfd/cros_ec_spi.o
drivers/mfd/cros_ec_spi.c: In function ‘cros_ec_spi_receive_response’:
drivers/mfd/cros_ec_spi.c:123:5: warning: format ‘%d’ expects argument of type
‘int’, but argument 4 has type ‘long int’ [-Wformat]
drivers/mfd/cros_ec_spi.c:157:3: warning: format ‘%d’ expects argument of type
‘int’, but argument 6 has type ‘long int’ [-Wformat]
drivers/mfd/cros_ec_spi.c:181:2: warning: format ‘%d’ expects argument of type
‘int’, but argument 4 has type ‘long int’ [-Wformat]

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-04-05 11:20:13 +02:00
Simon Glass
a17d94f0b6 mfd: Add ChromeOS EC SPI driver
This uses a SPI 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: Samuel Ortiz <sameo@linux.intel.com>
2013-04-05 11:20:13 +02:00