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path: root/drivers/mfd/cros_ec.c
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2014-06-03i2c: ChromeOS EC tunnel driverDoug Anderson
On ARM Chromebooks we have a few devices that are accessed by both the AP (the main "Application Processor") and the EC (the Embedded Controller). These are: * The battery (sbs-battery). * The power management unit tps65090. On the original Samsung ARM Chromebook these devices were on an I2C bus that was shared between the AP and the EC and arbitrated using some extranal GPIOs (see i2c-arb-gpio-challenge). The original arbitration scheme worked well enough but had some downsides: * It was nonstandard (not using standard I2C multimaster) * It only worked if the EC-AP communication was I2C * It was relatively hard to debug problems (hard to tell if i2c issues were caused by the EC, the AP, or some device on the bus). On the HP Chromebook 11 the design was changed to: * The AP/EC comms were still i2c, but the battery/tps65090 were no longer on the bus used for AP/EC communication. The battery was exposed to the AP through a limited i2c tunnel and tps65090 was exposed to the AP through a custom Linux driver. On the Samsung ARM Chromebook 2 the scheme is changed yet again, now: * The AP/EC comms are now using SPI for faster speeds. * The EC's i2c bus is exposed to the AP through a full i2c tunnel. The upstream "tegra124-venice2" uses the same scheme as the Samsung ARM Chromebook 2, though it has a different set of components on the other side of the bus. This driver supports the scheme used by the Samsung ARM Chromebook 2. Future patches to this driver could add support for the battery tunnel on the HP Chromebook 11 (and perhaps could even be used to access tps65090 on the HP Chromebook 11 instead of using a special driver, but I haven't researched that enough). Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Doug Anderson <dianders@chromium.org> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-06-03mfd: cros_ec: Sync to the latest cros_ec_commands.h from EC sourcesBill Richardson
This just updates include/linux/mfd/cros_ec_commands.h to match the latest EC version (which is the One True Source for such things). See <https://chromium.googlesource.com/chromiumos/platform/ec> [dianders: took today's ToT version from the Chromium OS EC; deleted references to cros_ec_dev and cros_ec_lpc since those aren't upstream yet] Signed-off-by: Bill Richardson <wfrichar@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>
2014-06-03mfd: cros_ec: cleanup: cros_ec.c is GPL licensed, like all the others.Bill Richardson
This module has always been GPL licensed. It was just missing the explicit declaration to avoid tainting the kernel. 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>
2014-01-06mfd: Constify struct mfd_cell where possibleGeert Uytterhoeven
As of commit 03e361b25ee8dfb1fd9b890072c23c4aae01c6c7 ("mfd: Stop setting refcounting pointers in original mfd_cell arrays"), the "cell" parameter of mfd_add_devices() is "const" again. Hence make all cell data passed to mfd_add_devices() const where possible. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2013-06-13mfd: cros_ec: Convert to managed resources for allocating memoryLee Jones
Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-04-05mfd: cros_ec: Export needed symbols for the i2c and spi modulesSamuel Ortiz
In order to fix those, when all cros code is modular: ERROR: "cros_ec_prepare_tx" [drivers/mfd/cros_ec_spi.ko] undefined! ERROR: "cros_ec_register" [drivers/mfd/cros_ec_spi.ko] undefined! ERROR: "cros_ec_remove" [drivers/mfd/cros_ec_spi.ko] undefined! ERROR: "cros_ec_suspend" [drivers/mfd/cros_ec_spi.ko] undefined! ERROR: "cros_ec_resume" [drivers/mfd/cros_ec_spi.ko] undefined! ERROR: "cros_ec_register" [drivers/mfd/cros_ec_i2c.ko] undefined! ERROR: "cros_ec_remove" [drivers/mfd/cros_ec_i2c.ko] undefined! ERROR: "cros_ec_suspend" [drivers/mfd/cros_ec_i2c.ko] undefined! ERROR: "cros_ec_resume" [drivers/mfd/cros_ec_i2c.ko] undefined! Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-04-05mfd: Add ChromeOS EC implementationSimon Glass
This is the base EC implementation, which provides a high level interface to the EC for use by the rest of the kernel. The actual communcations is dealt with by a separate protocol driver which registers itself with this interface. Interrupts are passed on through a notifier. A simple message structure is used to pass messages to the protocol driver. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Che-Liang Chiou <clchiou@chromium.org> Signed-off-by: Jonathan Kliegman <kliegs@chromium.org> Signed-off-by: Luigi Semenzato <semenzato@chromium.org> Signed-off-by: Olof Johansson <olofj@chromium.org> Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>