This commit adds driver model support to software emulated i2c bus driver.
This driver supports kernel-style device tree bindings. Fdt properties in use:
- compatible - "i2c-gpio"
- gpios - data and clock GPIO pin phandles
- delay-us - micro seconds delay between GPIOs toggle operations,
which is 1/4 of I2C speed clock period.
Added:
- Config: CONFIG_DM_I2C_GPIO
- File: drivers/i2c/i2c-gpio.c
- File: doc/device-tree-bindings/i2c/i2c-gpio.txt
Driver base code is taken from: drivers/i2c/soft-i2c.c, changes:
- use "i2c-gpio" naming
- update comments style
- move preprocesor macros into functions
- add device tree support
- add driver model i2c support
- code cleanup,
- add Kconfig entry
Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
Added braces in i2c_gpio_xfer() to fix style nit:
Signed-off-by: Simon Glass <sjg@chromium.org>
#
# Xilinx ZYNQ U-Boot
#
# (C) Copyright 2013 Xilinx, Inc.
#
# SPDX-License-Identifier: GPL-2.0+
#
1. About this
This document describes the information about Xilinx Zynq U-Boot -
like supported boards, ML status and TODO list.
2. Zynq boards
Xilinx Zynq-7000 All Programmable SoCs enable extensive system level
differentiation, integration, and flexibility through hardware, software,
and I/O programmability.
* zc70x
- zc702 (single qspi, gem0, mmc) [1]
- zc706 (dual parallel qspi, gem0, mmc) [2]
* zed (single qspi, gem0, mmc) [3]
* microzed (single qspi, gem0, mmc) [4]
* zc770
- zc770-xm010 (single qspi, gem0, mmc)
- zc770-xm011 (8 or 16 bit nand)
- zc770-xm012 (nor)
- zc770-xm013 (dual parallel qspi, gem1)
3. Building
# Configure for zc70x board
$ make zynq_zc70x_config
Configuring for zynq_zc70x board...
# Building default dts for zc702 board
$ make
# Building specified dts for zc706 board
$ make DEVICE_TREE=zynq-zc706
4. Bootmode
Zynq has a facility to read the bootmode from the slcr bootmode register
once user is setting through jumpers on the board - see page no:1546 on [5]
All possible bootmode values are defined in Table 6-2:Boot_Mode MIO Pins
on [5].
board_late_init() will read the bootmode values using slcr bootmode register
at runtime and assign the modeboot variable to specific bootmode string which
is intern used in autoboot.
SLCR bootmode register Bit[3:0] values
#define ZYNQ_BM_NOR 0x02
#define ZYNQ_BM_SD 0x05
#define ZYNQ_BM_JTAG 0x0
"modeboot" variable can assign any of "norboot", "sdboot" or "jtagboot"
bootmode strings at runtime.
5. Mainline status
- Added basic board configurations support.
- Added zynq u-boot bsp code - arch/arm/cpu/armv7/zynq
- Added zynq boards named - zc70x, zed, microzed, zc770_xm010, zc770_xm012, zc770_xm013
- Added zynq drivers:
serial - drivers/serial/serial_zynq.c
net - drivers/net/zynq_gem.c
mmc - drivers/mmc/zynq_sdhci.c
mmc - drivers/mmc/zynq_sdhci.c
spi- drivers/spi/zynq_spi.c
i2c - drivers/i2c/zynq_i2c.c
- Done proper cleanups on board configurations
- Added basic FDT support for zynq boards
- d-cache support for zynq_gem.c
6. TODO
- Add zynq boards support - zc770_xm011
- Add zynq qspi controller driver
- Add zynq nand controller driver
- Add FDT support on individual drivers
[1] http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm
[2] http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC706-G.htm
[3] http://zedboard.org/product/zedboard
[4] http://zedboard.org/product/microzed
[5] http://www.xilinx.com/support/documentation/user_guides/ug585-Zynq-7000-TRM.pdf
--
Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
Sun Dec 15 14:52:41 IST 2013
c54473cb25