Commit 001dde9400 ("mfd: cros ec: spi: Fix "in progress" error
signaling") pointed out some bad code, but its analysis and conclusion
was not 100% correct.
It *is* correct that we should not propagate result==EC_RES_IN_PROGRESS
for transport errors, because this has a special meaning -- that we
should follow up with EC_CMD_GET_COMMS_STATUS until the EC is no longer
busy. This is definitely the wrong thing for many commands, because
among other problems, EC_CMD_GET_COMMS_STATUS doesn't actually retrieve
any RX data from the EC, so commands that expected some data back will
instead start processing junk.
For such commands, the right answer is to either propagate the error
(and return that error to the caller) or resend the original command
(*not* EC_CMD_GET_COMMS_STATUS).
Unfortunately, commit 001dde9400 forgets a crucial point: that for
some long-running operations, the EC physically cannot respond to
commands any more. For example, with EC_CMD_FLASH_ERASE, the EC may be
re-flashing its own code regions, so it can't respond to SPI interrupts.
Instead, the EC prepares us ahead of time for being busy for a "long"
time, and fills its hardware buffer with EC_SPI_PAST_END. Thus, we
expect to see several "transport" errors (or, messages filled with
EC_SPI_PAST_END). So we should really translate that to a retryable
error (-EAGAIN) and continue sending EC_CMD_GET_COMMS_STATUS until we
get a ready status.
IOW, it is actually important to treat some of these "junk" values as
retryable errors.
Together with commit 001dde9400, this resolves bugs like the
following:
1. EC_CMD_FLASH_ERASE now works again (with commit 001dde9400, we
would abort the first time we saw EC_SPI_PAST_END)
2. Before commit 001dde9400, transport errors (e.g.,
EC_SPI_RX_BAD_DATA) seen in other commands (e.g.,
EC_CMD_RTC_GET_VALUE) used to yield junk data in the RX buffer; they
will now yield -EAGAIN return values, and tools like 'hwclock' will
simply fail instead of retrieving and re-programming undefined time
values
Fixes: 001dde9400 ("mfd: cros ec: spi: Fix "in progress" error signaling")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The EC SPI driver prevents SPI transfers being to rapidly by keeping
track of the time the last transfer was issued via the
'last_transfer_ns' variable. Previously, if the 'last_transfer_ns'
variable was zero, this indicated that no previous transfer had been
sent and that no delay was needed. However, the EC SPI driver has
been updated to always initialise the 'last_transfer_ns' variable
during probe and therefore, it is no longer necessary to test if it
is zero. Remove the code that checks if this variable is zero.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
For host commands that take a long time to process, cros ec can return
early by signaling a EC_RES_IN_PROGRESS result. The host must then poll
status with EC_CMD_GET_COMMS_STATUS until completion of the command.
None of the above applies when data link errors are encountered. When
errors such as EC_SPI_PAST_END are encountered during command
transmission, it usually means the command was not received by the EC.
Treating such errors as if they were 'EC_RES_IN_PROGRESS' results is
almost always the wrong decision, and can result in host commands
silently being lost.
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
On the Tegra124 Nyan-Big chromebook the very first SPI message sent to
the EC is failing.
The Tegra SPI driver configures the SPI chip-selects to be active-high
by default (and always has for many years). The EC SPI requires an
active-low chip-select and so the Tegra chip-select is reconfigured to
be active-low when the EC SPI driver calls spi_setup(). The problem is
that if the first SPI message to the EC is sent too soon after
reconfiguring the SPI chip-select, it fails.
The EC SPI driver prevents back-to-back SPI messages being sent too
soon by keeping track of the time the last transfer was sent via the
variable 'last_transfer_ns'. To prevent the very first transfer being
sent too soon, initialise the 'last_transfer_ns' variable after calling
spi_setup() and before sending the first SPI message.
Cc: <stable@vger.kernel.org>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
This is a sucky change to bump up the time we'll wait for the EC. Why
is it sucky? If 200ms for a transfer is a common thing it will have a
massively bad impact on keyboard responsiveness.
It still seems like a good idea to do this, though, because we have a
gas gauge that claims that in an extreme case it could stretch the i2c
clock for 144ms. It's not a common case so it shouldn't affect
responsiveness, but it can happen. It's much better to have a single
slow keyboard response than to start returning errors when we don't
have to.
In newer EC designs we should probably implement a virtual battery to
respond to the kernel to insulate the kernel from these types of
issues.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
WARNING: Comparisons should place the constant on the right side of the test
+ BUG_ON(EC_MSG_PREAMBLE_COUNT > ec_dev->din_size);
WARNING: Comparisons should place the constant on the right side of the test
+ BUG_ON(EC_MSG_PREAMBLE_COUNT > ec_dev->din_size);
total: 0 errors, 2 warnings, 731 lines checked
Signed-off-by: Lee Jones <lee.jones@linaro.org>
cros_ec_cmd_xfer_spi and cros_ec_pkt_xfer_spi generally work like
this:
- Pull CS down (active), wait a bit, then send a command
- Wait for response (multiple requests)
- Wait a while, pull CS up (inactive)
These operations, individually, lock the SPI bus, but there is
nothing preventing the SPI framework from interleaving messages
intended for other devices as the bus is unlocked in between.
This is a problem as the EC expects CS to be held low for the
whole duration.
Solution: Lock the SPI bus during the whole transaction, to make
sure that no other messages can be interleaved.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
An spi_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
The Documentation/devicetree/bindings/mfd/cros-ec.txt DT binding doc lists
"google,cros-ec-spi" as a compatible string but the corresponding driver
does not have an OF match table. Add the table to the driver so the SPI
core can do an OF style match.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Some ECs need a little time for waking up before they can accept
SPI data at a high speed. This is configurable via a DT property
"google,cros-ec-spi-pre-delay".
This patch makes the cros_ec_spi driver to cause a delay before
the beginning of a SPI transaction, to make sure that the EC has
already woken up, if the property has been defined in the DTS.
Signed-off-by: Alexandru M Stan <amstan@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Chris Zhong <zyw@rock-chips.com>
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>
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>
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>
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>
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>
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>
Now that there's a central cros_ec_cmd_xfer(), move the locking
out of the SPI driver.
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>
If someone sends a EC_CMD_REBOOT_EC to the EC, the EC will likely be
unresponsive for quite a while. Add a delay to the end of the command
to prevent random failures of future commands.
NOTES:
* This could be optimized a bit by simply delaying the next command
sent, but EC_CMD_REBOOT_EC is such a rare command that the extra
complexity doesn't seem worth it.
* This is a bit of an "ugly hack" since the SPI driver is effectively
snooping on the communication and making a lot of assumptions. It
would be nice to architect in some better solution long term.
* This same logic probably needs to be applied to the i2c driver.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
- Checkpatch fixes throughout the subsystem
- Use Regmap to handle IRQs in max77686, extcon-max77693 and mc13xxx-core
- Use DMA in rtsx_pcr
- Restrict building on unsupported architectures on timberdale, cs5535
- SPI hardening in cros_ec_spi
- More robust error handing in asic3, cros_ec, ab8500-debugfs,
max77686 and pcf50633-core
- Reorder PM runtime and regulator handing during shutdown in arizona
- Enable wakeup in cros_ec_spi
- Unused variable/code clean-up in pm8921-core, cros_ec, htc-i2cpld,
tps65912-spi, wm5110-tables and ab8500-debugfs
- Add regulator handing into suspend() in sec-core
- Remove pointless wrapper functions in extcon-max77693 and i2c-cros-ec-tunnel
- Use cross-architecture friendly data sizes in stmpe-i2c, arizona,
max77686 and tps65910
- Device Tree documentation updates throughout
- Provide power management support in max77686
- Few OF clean-ups in max77686
- Use manged resources in tps6105x
== New drivers/supported devices ==
- Add support for s2mpu02 to sec-core
- Add support for Allwinner A32 to sun6i-prcm
- Add support for Maxim 77802 in max77686
- Add support for DA9063 AD in da9063
- Add new driver for Intel PMICs (generic) and specifically Crystal Cove
== (Re-)moved drivers ==
- Move out keyboard functionality cros_ec ==> input/keyboard/cros_ec_keyb
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Merge tag 'mfd-for-linus-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD update from Lee Jones:
"Changes to existing drivers:
- checkpatch fixes throughout the subsystem
- use Regmap to handle IRQs in max77686, extcon-max77693 and
mc13xxx-core
- use DMA in rtsx_pcr
- restrict building on unsupported architectures on timberdale,
cs5535
- SPI hardening in cros_ec_spi
- more robust error handing in asic3, cros_ec, ab8500-debugfs,
max77686 and pcf50633-core
- reorder PM runtime and regulator handing during shutdown in arizona
- enable wakeup in cros_ec_spi
- unused variable/code clean-up in pm8921-core, cros_ec, htc-i2cpld,
tps65912-spi, wm5110-tables and ab8500-debugfs
- add regulator handing into suspend() in sec-core
- remove pointless wrapper functions in extcon-max77693 and
i2c-cros-ec-tunnel
- use cross-architecture friendly data sizes in stmpe-i2c, arizona,
max77686 and tps65910
- devicetree documentation updates throughout
- provide power management support in max77686
- few OF clean-ups in max77686
- use manged resources in tps6105x
New drivers/supported devices:
- add support for s2mpu02 to sec-core
- add support for Allwinner A32 to sun6i-prcm
- add support for Maxim 77802 in max77686
- add support for DA9063 AD in da9063
- new driver for Intel PMICs (generic) and specifically Crystal Cove
(Re-)moved drivers ==
- move out keyboard functionality cros_ec ==> input/keyboard/cros_ec_keyb"
* tag 'mfd-for-linus-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (101 commits)
MAINTAINERS: Update MFD repo location
mfd: omap-usb-host: Fix improper mask use.
mfd: arizona: Only free the CTRLIF_ERR IRQ if we requested it
mfd: arizona: Add missing handling for ISRC3 under/overclocked
mfd: wm5110: Add new interrupt register definitions
mfd: arizona: Rename thermal shutdown interrupt
mfd: wm5110: Add in the output done interrupts
mfd: wm5110: Remove non-existant interrupts
mfd: tps65912-spi: Remove unused variable
mfd: htc-i2cpld: Remove unused code
mfd: da9063: Add support for AD silicon variant
mfd: arizona: Map MICVDD from extcon device to the Arizona core
mfd: arizona: Add MICVDD to mapped regulators for wm8997
mfd: max77686: Ensure device type IDs are architecture agnostic
mfd: max77686: Add Maxim 77802 PMIC support
mfd: tps6105x: Use managed resources when allocating memory
mfd: wm8997-tables: Suppress 'line over 80 chars' warnings
mfd: kempld-core: Correct a variety of checkpatch warnings
mfd: ipaq-micro: Fix coding style errors/warnings reported by checkpatch
mfd: si476x-cmd: Remedy checkpatch style complains
...
Replace the ever recurring:
ts = ktime_get_ts();
ns = timespec_to_ns(&ts);
with
ns = ktime_get_ns();
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
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>
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>
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>
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>
Some commands take a while to execute. Use -EAGAIN to signal this to the
caller.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
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>
Set the device as wakeup capable and register the wakeup source.
Note: Though it makes more sense to have the SPI framework do this,
(either via device tree or by board_info)
this change is as per an existing mail chain:
https://lkml.org/lkml/2009/8/27/291
Signed-off-by: Prathyush K <prathyush.k@samsung.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
cros_ec_spi makes the assumption that a 0-length message will put the
spi chip select back to normal (non cs_toggle mode). This used to be
the case back on kernel-3.8 on the spi-s3c64xx driver but doesn't
appear to be true anymore. It seems like it was a pretty questionable
assumption to begin with, so let's fix the code to be more robust. We
know that a message with a single 0-length segment _will_ put things
back in order. Change cros_ec_spi to handle this.
This wasn't a problem on the main user of cros_ec_spi upstream (tegra)
because it specified 'google,cros-ec-spi-msg-delay'.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
