+++ /dev/null
-/*
- * drivers/i2c/busses/i2c-ixp2000.c
- *
- * I2C adapter for IXP2000 systems using GPIOs for I2C bus
- *
- * Author: Deepak Saxena <dsaxena@plexity.net>
- * Based on IXDP2400 code by: Naeem M. Afzal <naeem.m.afzal@intel.com>
- * Made generic by: Jeff Daly <jeffrey.daly@intel.com>
- *
- * Copyright (c) 2003-2004 MontaVista Software Inc.
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- *
- * From Jeff Daly:
- *
- * I2C adapter driver for Intel IXDP2xxx platforms. This should work for any
- * IXP2000 platform if it uses the HW GPIO in the same manner. Basically,
- * SDA and SCL GPIOs have external pullups. Setting the respective GPIO to
- * an input will make the signal a '1' via the pullup. Setting them to
- * outputs will pull them down.
- *
- * The GPIOs are open drain signals and are used as configuration strap inputs
- * during power-up so there's generally a buffer on the board that needs to be
- * 'enabled' to drive the GPIOs.
- */
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/platform_device.h>
-#include <linux/module.h>
-#include <linux/i2c.h>
-#include <linux/i2c-algo-bit.h>
-#include <linux/slab.h>
-
-#include <mach/hardware.h> /* Pick up IXP2000-specific bits */
-#include <mach/gpio-ixp2000.h>
-
-static inline int ixp2000_scl_pin(void *data)
-{
- return ((struct ixp2000_i2c_pins*)data)->scl_pin;
-}
-
-static inline int ixp2000_sda_pin(void *data)
-{
- return ((struct ixp2000_i2c_pins*)data)->sda_pin;
-}
-
-
-static void ixp2000_bit_setscl(void *data, int val)
-{
- int i = 5000;
-
- if (val) {
- gpio_line_config(ixp2000_scl_pin(data), GPIO_IN);
- while(!gpio_line_get(ixp2000_scl_pin(data)) && i--);
- } else {
- gpio_line_config(ixp2000_scl_pin(data), GPIO_OUT);
- }
-}
-
-static void ixp2000_bit_setsda(void *data, int val)
-{
- if (val) {
- gpio_line_config(ixp2000_sda_pin(data), GPIO_IN);
- } else {
- gpio_line_config(ixp2000_sda_pin(data), GPIO_OUT);
- }
-}
-
-static int ixp2000_bit_getscl(void *data)
-{
- return gpio_line_get(ixp2000_scl_pin(data));
-}
-
-static int ixp2000_bit_getsda(void *data)
-{
- return gpio_line_get(ixp2000_sda_pin(data));
-}
-
-struct ixp2000_i2c_data {
- struct ixp2000_i2c_pins *gpio_pins;
- struct i2c_adapter adapter;
- struct i2c_algo_bit_data algo_data;
-};
-
-static int ixp2000_i2c_remove(struct platform_device *plat_dev)
-{
- struct ixp2000_i2c_data *drv_data = platform_get_drvdata(plat_dev);
-
- platform_set_drvdata(plat_dev, NULL);
-
- i2c_del_adapter(&drv_data->adapter);
-
- kfree(drv_data);
-
- return 0;
-}
-
-static int ixp2000_i2c_probe(struct platform_device *plat_dev)
-{
- int err;
- struct ixp2000_i2c_pins *gpio = plat_dev->dev.platform_data;
- struct ixp2000_i2c_data *drv_data =
- kzalloc(sizeof(struct ixp2000_i2c_data), GFP_KERNEL);
-
- if (!drv_data)
- return -ENOMEM;
- drv_data->gpio_pins = gpio;
-
- drv_data->algo_data.data = gpio;
- drv_data->algo_data.setsda = ixp2000_bit_setsda;
- drv_data->algo_data.setscl = ixp2000_bit_setscl;
- drv_data->algo_data.getsda = ixp2000_bit_getsda;
- drv_data->algo_data.getscl = ixp2000_bit_getscl;
- drv_data->algo_data.udelay = 6;
- drv_data->algo_data.timeout = HZ;
-
- strlcpy(drv_data->adapter.name, plat_dev->dev.driver->name,
- sizeof(drv_data->adapter.name));
- drv_data->adapter.algo_data = &drv_data->algo_data,
-
- drv_data->adapter.dev.parent = &plat_dev->dev;
-
- gpio_line_config(gpio->sda_pin, GPIO_IN);
- gpio_line_config(gpio->scl_pin, GPIO_IN);
- gpio_line_set(gpio->scl_pin, 0);
- gpio_line_set(gpio->sda_pin, 0);
-
- if ((err = i2c_bit_add_bus(&drv_data->adapter)) != 0) {
- dev_err(&plat_dev->dev, "Could not install, error %d\n", err);
- kfree(drv_data);
- return err;
- }
-
- platform_set_drvdata(plat_dev, drv_data);
-
- return 0;
-}
-
-static struct platform_driver ixp2000_i2c_driver = {
- .probe = ixp2000_i2c_probe,
- .remove = ixp2000_i2c_remove,
- .driver = {
- .name = "IXP2000-I2C",
- .owner = THIS_MODULE,
- },
-};
-
-module_platform_driver(ixp2000_i2c_driver);
-
-MODULE_AUTHOR ("Deepak Saxena <dsaxena@plexity.net>");
-MODULE_DESCRIPTION("IXP2000 GPIO-based I2C bus driver");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:IXP2000-I2C");
-
projects / deliverable / linux.git / commitdiff
