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2019-09-17AUTHORS: Move src/device copyrights into AUTHORS fileMartin Roth
As discussed on the mailing list and voted upon, the coreboot project is going to move the majority of copyrights out of the headers and into an AUTHORS file. This will happen a bit at a time, as we'll be unifying license headers at the same time. Additional cleanup - Unify "Inc" to "Inc." and "LLC." to "LLC" Signed-off-by: Martin Roth <martin@coreboot.org> Change-Id: Ie03a3ce1f6085494bd5f38da76e2467970cf301a Reviewed-on: https://review.coreboot.org/c/coreboot/+/35430 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2017-08-18Reinvent I2C opsNico Huber
Do not use the global platform_i2c_transfer() function that can only be implemented by a single driver. Instead, make a `struct device` aware transfer() function the only interface function for I2C controller dri- vers to implement. To not force the slave device drivers to be implemented either above generic I2C or specialized SMBus operations, we support SMBus control- lers in the slave device interface too. We start with four simple slave functions: i2c_readb(), i2c_writeb(), i2c_readb_at() and i2c_writeb_at(). They are all compatible to respec- tive SMBus functions. But we keep aliases because it would be weird to force e.g. an I2C EEPROM driver to call smbus_read_byte(). Change-Id: I98386f91bf4799ba3df84ec8bc0f64edd4142818 Signed-off-by: Nico Huber <nico.huber@secunet.com> Reviewed-on: https://review.coreboot.org/20846 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
2017-08-18include/device: Split i2c.h into threeNico Huber
Split `i2c.h` into three pieces to ease reuse of the generic defi- nitions. No code is changed. * `i2c.h` - keeps the generic definitions * `i2c_simple.h` - holds the current, limited to one controller driver per board, devicetree independent I2C interface * `i2c_bus.h` - will become the devicetree compatible interface for native I2C (e.g. non-SMBus) controllers Change-Id: I382d45c70f9314588663e1284f264f877469c74d Signed-off-by: Nico Huber <nico.huber@secunet.com> Reviewed-on: https://review.coreboot.org/20845 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2017-08-14i2c: Move to Linux like `struct i2c_msg`Nico Huber
Our current struct for I2C segments `i2c_seg` was close to being compa- tible to the Linux version `i2c_msg`, close to being compatible to SMBus and close to being readable (e.g. what was `chip` supposed to mean?) but turned out to be hard to fix. Instead of extending it in a backwards compatible way (and not touching current controller drivers), replace it with a Linux source compatible `struct i2c_msg` and patch all the drivers and users with Coccinelle. The new `struct i2c_msg` should ease porting drivers from Linux and help to write SMBus compatible controller drivers. Beside integer type changes, the field `read` is replaced with a generic field `flags` and `chip` is renamed to `slave`. Patched with Coccinelle using the clumsy spatch below and some manual changes: * Nested struct initializers and one field access skipped by Coccinelle. * Removed assumption in the code that I2C_M_RD is 1. * In `i2c.h`, changed all occurences of `chip` to `slave`. @@ @@ -struct i2c_seg +struct i2c_msg @@ identifier msg; expression e; @@ ( struct i2c_msg msg = { - .read = 0, + .flags = 0, }; | struct i2c_msg msg = { - .read = 1, + .flags = I2C_M_RD, }; | struct i2c_msg msg = { - .chip = e, + .slave = e, }; ) @@ struct i2c_msg msg; statement S1, S2; @@ ( -if (msg.read) +if (msg.flags & I2C_M_RD) S1 else S2 | -if (msg.read) +if (msg.flags & I2C_M_RD) S1 ) @@ struct i2c_msg *msg; statement S1, S2; @@ ( -if (msg->read) +if (msg->flags & I2C_M_RD) S1 else S2 | -if (msg->read) +if (msg->flags & I2C_M_RD) S1 ) @@ struct i2c_msg msg; expression e; @@ ( -msg.read = 0; +msg.flags = 0; | -msg.read = 1; +msg.flags = I2C_M_RD; | -msg.read = e; +msg.flags = e ? I2C_M_RD : 0; | -!!(msg.read) +(msg.flags & I2C_M_RD) | -(msg.read) +(msg.flags & I2C_M_RD) ) @@ struct i2c_msg *msg; expression e; @@ ( -msg->read = 0; +msg->flags = 0; | -msg->read = 1; +msg->flags = I2C_M_RD; | -msg->read = e; +msg->flags = e ? I2C_M_RD : 0; | -!!(msg->read) +(msg->flags & I2C_M_RD) | -(msg->read) +(msg->flags & I2C_M_RD) ) @@ struct i2c_msg msg; @@ -msg.chip +msg.slave @@ struct i2c_msg *msg; expression e; @@ -msg[e].chip +msg[e].slave @ slave disable ptr_to_array @ struct i2c_msg *msg; @@ -msg->chip +msg->slave Change-Id: Ifd7cabf0a18ffd7a1def25d1d7059b713d0b7ea9 Signed-off-by: Nico Huber <nico.huber@secunet.com> Reviewed-on: https://review.coreboot.org/20542 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Werner Zeh <werner.zeh@siemens.com> Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
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>
2016-03-21device: 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>