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2016-06-09device: i2c: Add support for I2C bus operationsDuncan Laurie
In order to support doing bus operations on an I2C device that is described in the devicetree there needs to be some linkage of the device and the existing opaque I2C controller bus number. This is provided in a similar fashion to the existing SMBUS operations but modified to fit within the existing I2C infrastructure. Variants of the existing I2C helper functions are provided that will obtain the bus number that corresponds to this device by looking for the SOC-provided I2C bus operation structure to provide a function that will make that translation. For example an SOC using a PCI I2C controller at 0:15.0 could use: soc/intel/.../i2c.c: static int i2c_dev_to_bus(struct device *dev) { if (dev->path.pci.devfn == PCI_DEVFN(0x15, 0)) return 0; return -1; } static struct i2c_bus_operation i2c_bus_ops = { .dev_to_bus = &i2c_dev_to_bus } static struct device_operations i2c_dev_ops = { .ops_i2c_bus = &i2c_bus_ops ... } With an I2C device on that bus at address 0x1a described in the tree: devicetree.cb: device pci 15.0 on # I2C0 chip drivers/i2c/sample device i2c 1a.0 on end end end That driver can then do I2C transactions with the device object without needing to know that the SOC-specific bus number that this I2C device lives on is "0". For example it could read a version value from register address 0 with a byte transaction: drivers/i2c/sample/sample.c: static void i2c_sample_enable(struct device *dev) { uint8_t ver; if (!i2c_dev_readb(dev, 0x00, &ver)) printk(BIOS_INFO, "I2C %s version 0x02x\n", dev_path(dev), ver); } Change-Id: I6c41c8e0d10caabe01cc41da96382074de40e91e Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-on: https://review.coreboot.org/15100 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2016-05-28acpi_device: Add support for writing ACPI I2C descriptorsDuncan Laurie
Add required definitions to describe an ACPI I2C bus and a method to write the I2cSerialBus() descriptor to the SSDT. This will be used by device drivers to describe their I2C resources to the OS. The devicetree i2c device can supply the address and 7 or 10 bit mode as well as indicate the GPIO controller device, and the bus speed can be fixed or configured by the driver. chip.h: struct drivers_i2c_generic_config { enum i2c_speed bus_speed; }; generic.c: void acpi_fill_ssdt_generator(struct device *dev) { struct drivers_i2c_generic_config *config = dev->chip_info; struct acpi_i2c i2c = { .address = dev->path->i2c.device, .mode_10bit = dev->path.i2c.mode_10bit, .speed = config->bus_speed ? : I2C_SPEED_FAST, .resource = acpi_device_path(dev->bus->dev) }; ... acpi_device_write_i2c(&i2c); ... } devicetree.cb: device pci 15.0 on chip drivers/i2c/generic device i2c 10.0 on end end end SSDT.dsl: I2cSerialBus (0x10, ControllerInitiated, 400000, AddressingMode7Bit, "\\_SB.PCI0.I2C0", 0, ResourceConsumer) Change-Id: I598401ac81a92c72f19da0271af1e218580a6c49 Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-on: https://review.coreboot.org/14935 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2016-03-21device: Add i2c read/write register field APIYidi Lin
i2c_read_field() - read the value from the specific register field i2c_write_field() - write the value to the specific register field BRANCH=none BUG=none TEST=none Change-Id: I2098715b4583c1936c93b3ff45ec330910964304 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 0817fc76d07491b39c066f1393a6435f0831b50c Original-Change-Id: I92c187a89d10cfcecf3dfd9291e0bc015459c393 Original-Signed-off-by: Yidi Lin <yidi.lin@mediatek.com> Original-Reviewed-on: https://chromium-review.googlesource.com/332712 Original-Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/14105 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org> Reviewed-by: Martin Roth <martinroth@google.com>
2016-03-12device/i2c: Add i2c_read_bytes() APIJitao Shi
Add multi-bytes read support. BRANCH=none BUG=none TEST=saw edid log and dev screen Change-Id: I106be98e751e2a3b998ccaedb28f71f3c6e18994 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 94ee0b834947e8d971943aa24e61a9353c7b7306 Original-Change-Id: Iac5fe497da92b7d09383e0d6a04d98709aea5b20 Original-Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> Original-Reviewed-on: https://chromium-review.googlesource.com/325211 Original-Commit-Ready: Yidi Lin <yidi.lin@mediatek.com> Original-Tested-by: Yidi Lin <yidi.lin@mediatek.com> Original-Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/13978 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-10-31tree: drop last paragraph of GPL copyright headerPatrick Georgi
It encourages users from writing to the FSF without giving an address. Linux also prefers to drop that and their checkpatch.pl (that we imported) looks out for that. This is the result of util/scripts/no-fsf-addresses.sh with no further editing. Change-Id: Ie96faea295fe001911d77dbc51e9a6789558fbd6 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Reviewed-on: http://review.coreboot.org/11888 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
2015-05-21Remove address from GPLv2 headersPatrick Georgi
As per discussion with lawyers[tm], it's not a good idea to shorten the license header too much - not for legal reasons but because there are tools that look for them, and giving them a standard pattern simplifies things. However, we got confirmation that we don't have to update every file ever added to coreboot whenever the FSF gets a new lease, but can drop the address instead. util/kconfig is excluded because that's imported code that we may want to synchronize every now and then. $ find * -type f -exec sed -i "s:Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, *MA[, ]*02110-1301[, ]*USA:Foundation, Inc.:" {} + $ find * -type f -exec sed -i "s:Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA:Foundation, Inc.:" {} + $ find * -type f -exec sed -i "s:Foundation, Inc., 59 Temple Place[-, ]*Suite 330, Boston, MA *02111-1307[, ]*USA:Foundation, Inc.:" {} + $ find * -type f -exec sed -i "s:Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.:Foundation, Inc.:" {} + $ find * -type f -a \! -name \*.patch \ -a \! -name \*_shipped \ -a \! -name LICENSE_GPL \ -a \! -name LGPL.txt \ -a \! -name COPYING \ -a \! -name DISCLAIMER \ -exec sed -i "/Foundation, Inc./ N;s:Foundation, Inc.* USA\.* *:Foundation, Inc. :;s:Foundation, Inc. $:Foundation, Inc.:" {} + Change-Id: Icc968a5a5f3a5df8d32b940f9cdb35350654bef9 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Reviewed-on: http://review.coreboot.org/9233 Tested-by: build bot (Jenkins) Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
2014-12-30i2c: Add software_i2c driver for I2C debugging and emulationJulius Werner
This patch adds I2C emulation in software through raw toggling of the SDA/SCL lines. Platforms need to provide bindings to toggle their respective I2C busses for this to work (e.g. by pinmuxing them as GPIOs, currently only enabled for Tegra). This is mostly useful as a debugging feature, to drive unusual states on a bus and closely monitor the device output without the need of a bus analyzer. It provides a few functions to "wedge" an I2C bus by aborting a transaction at certain points, which can be used to test if a system can correctly recover from an ill-timed reboot. However, it can also dynamically replace the existing I2C transfer functions and drive some/all I2C transfers on the system, which might be useful if a driver for the actual I2C controller hardware is not (yet) available. Based on original code by Doug Anderson <dianders@chromium.org> and Hung-ying Tyan <tyanh@chromium.org> for the ChromeOS embedded controller project. BRANCH=None BUG=chrome-os-partner:28323 TEST=Spread tegra_software_i2c_init()/tegra_software_i2c_disable() through the code and see that everything still works. Original-Change-Id: I9ee7ccbd1efb38206669a35d0c3318af16f8be63 Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/198791 Original-Reviewed-by: Doug Anderson <dianders@chromium.org> Original-Reviewed-by: Tom Warren <twarren@nvidia.com> Original-Reviewed-by: Stefan Reinauer <reinauer@chromium.org> (cherry picked from commit 8f71503dbbd74c5298e90e2163b67d4efe3e89db) Signed-off-by: Marc Jones <marc.jones@se-eng.com> Change-Id: Id6c5f75bb5baaabd62b6b1fc26c2c71d9f1ce682 Reviewed-on: http://review.coreboot.org/7947 Tested-by: build bot (Jenkins) Reviewed-by: David Hendricks <dhendrix@chromium.org>
2014-12-16i2c: Replace the i2c API.Gabe Black
The new API is in use in depthcharge and is based around the "i2c_transfer" function instead of i2c_read and i2c_write. The new function takes an array of i2c_seg structures which represent each portion of the transfer after a start bit and before the stop bit. If there's more than one segment, they're seperated by repeated starts. Some wrapper functions have also been added which make certain common operations easy. These include reading or writing a byte from a register or reading or writing a blob of raw data. The i2c device drivers generally use these wrappers but can call the i2c_transfer function directly if the need something different. The tegra i2c driver was very similar to the one in depthcharge and was simple to convert. The Exynos 5250 and 5420 drivers were ported from depthcharge and replace the ones in coreboot. The Exynos 5420 driver was ported from the high speed portion of the one in coreboot and was straightforward to port back. The low speed portion and the Exynos 5250 drivers had been transplanted from U-Boot and were replaced with the depthcharge implementation. BUG=None TEST=Built and booted on nyan with and without EFS. Built and booted on, pit and daisy. BRANCH=None Original-Change-Id: I1e98c3fa2560be25444ab3d0394bb214b9d56e93 Original-Signed-off-by: Gabe Black <gabeblack@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/193561 Original-Reviewed-by: David Hendricks <dhendrix@chromium.org> Original-Reviewed-by: Jimmy Zhang <jimmzhang@nvidia.com> Original-Tested-by: Jimmy Zhang <jimmzhang@nvidia.com> Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org> Original-Commit-Queue: Gabe Black <gabeblack@chromium.org> Original-Tested-by: Gabe Black <gabeblack@chromium.org> (cherry picked from commit 00c423fb2c06c69d580ee3ec0a3892ebf164a5fe) This cherry-pick required additional changes to the following: src/cpu/allwinner/a10/twi.c src/drivers/xpowers/axp209/axp209.c Signed-off-by: Marc Jones <marc.jones@se-eng.com> Change-Id: I691959c66308eeeec219b1bec463b8b365a246d7 Reviewed-on: http://review.coreboot.org/7751 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2013-07-10i2c: Change the type of the data parameter to uint8_t.Gabe Black
Data is intended to be a byte array, so it should be described by a type which has a fixed size equal to an 8 bit byte. Also, the data passed to write shouldn't be modified and can be const. Change-Id: I6466303d962998f6c37c2d4006a39c2d79a235c1 Signed-off-by: Gabe Black <gabeblack@chromium.org> Reviewed-on: http://review.coreboot.org/3721 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2013-04-09replace device/i2c.h with simpler versionDavid Hendricks
The existing header was imported along with the Exynos code and left mostly unchanged. This is the first patch in a series intended to replace the imported u-boot I2C API with a much simpler and cleaner interface: - We only need to expose i2c_read() and i2c_write() in our public API. Everything else is board/chip-dependent and should remain hidden away. - i2c_read and i2c_write functions will take bus number as an arg and we'll eliminate i2c_get_bus and i2c_set_bus. Those are prone to error and end up cluttering the code since the user needs to save the old bus number, set the new one, do the read/write, and restore the old value (3 added steps to do a simple transaction). - Stop setting default values for board-specific things like SPD and RTC bus numbers (as if we always have an SPD or RTC on I2C). - Death to all the trivial inline wrappers. And in case there was any doubt, we really don't care about the MPC8xx. Though if we did then we would not pollute the public API with its idiosyncrasies. Change-Id: I4410a3c82ed5a6b2e80e3d8c0163464a9ca7c3b0 Signed-off-by: David Hendricks <dhendrix@chromium.org> Reviewed-on: http://review.coreboot.org/3043 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
2013-02-06replace uchar and uint with standard types in generic i2c headerDavid Hendricks
Change-Id: Ie72985bb5291bcef2e837a2f4f2ec929a0c086ce Signed-off-by: David Hendricks <dhendrix@chromium.org> Reviewed-on: http://review.coreboot.org/2290 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2012-12-29import i2c header from u-bootDavid Hendricks
This just imports a header. We may wish to modify the i2c interface and/or unify it with the smbus interface we currently have. Change-Id: I314f3aef62be936456c6c3e164a3db2c473b8792 Signed-off-by: David Hendricks <dhendrix@chromium.org> Reviewed-on: http://review.coreboot.org/2079 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>