1bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks/* 2bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * Copyright (C) 2005 Simtec Electronics 3bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * Ben Dooks <ben@simtec.co.uk> 4bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * 5bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * Simtec Generic I2C Controller 6bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * 7bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * This program is free software; you can redistribute it and/or modify 8bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * it under the terms of the GNU General Public License as published by 9bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * the Free Software Foundation; either version 2 of the License 10bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * 11bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * This program is distributed in the hope that it will be useful, 12bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * but WITHOUT ANY WARRANTY; without even the implied warranty of 13bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * GNU General Public License for more details. 15bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * 16bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * You should have received a copy of the GNU General Public License 17bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * along with this program; if not, write to the Free Software 18bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks*/ 20bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 21bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/kernel.h> 22bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/module.h> 23bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/init.h> 24bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/delay.h> 25bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/platform_device.h> 265a0e3ad6af8660be21ca98a971cd00f331318c05Tejun Heo#include <linux/slab.h> 272178218027e4da0608219fae1d02e5c88f4e560dH Hartley Sweeten#include <linux/io.h> 28bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 29bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/i2c.h> 30bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#include <linux/i2c-algo-bit.h> 31bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 32bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstruct simtec_i2c_data { 33bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct resource *ioarea; 34bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks void __iomem *reg; 35bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct i2c_adapter adap; 36bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct i2c_algo_bit_data bit; 37bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks}; 38bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 39bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#define CMD_SET_SDA (1<<2) 40bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#define CMD_SET_SCL (1<<3) 41bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 42bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#define STATE_SDA (1<<0) 43bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks#define STATE_SCL (1<<1) 44bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 45bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks/* i2c bit-bus functions */ 46bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 47bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic void simtec_i2c_setsda(void *pw, int state) 48bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks{ 49bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct simtec_i2c_data *pd = pw; 50bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks writeb(CMD_SET_SDA | (state ? STATE_SDA : 0), pd->reg); 51bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks} 52bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 53bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic void simtec_i2c_setscl(void *pw, int state) 54bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks{ 55bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct simtec_i2c_data *pd = pw; 56bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks writeb(CMD_SET_SCL | (state ? STATE_SCL : 0), pd->reg); 57bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks} 58bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 59bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic int simtec_i2c_getsda(void *pw) 60bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks{ 61bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct simtec_i2c_data *pd = pw; 62bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks return readb(pd->reg) & STATE_SDA ? 1 : 0; 63bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks} 64bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 65bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic int simtec_i2c_getscl(void *pw) 66bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks{ 67bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct simtec_i2c_data *pd = pw; 68bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks return readb(pd->reg) & STATE_SCL ? 1 : 0; 69bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks} 70bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 71bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks/* device registration */ 72bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 73bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic int simtec_i2c_probe(struct platform_device *dev) 74bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks{ 75bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct simtec_i2c_data *pd; 76bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct resource *res; 77bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks int size; 78bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks int ret; 79bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 80bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL); 81bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks if (pd == NULL) { 82bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks dev_err(&dev->dev, "cannot allocate private data\n"); 83bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks return -ENOMEM; 84bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks } 85bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 86bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks platform_set_drvdata(dev, pd); 87bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 88bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks res = platform_get_resource(dev, IORESOURCE_MEM, 0); 89bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks if (res == NULL) { 90bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks dev_err(&dev->dev, "cannot find IO resource\n"); 91bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks ret = -ENOENT; 92bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks goto err; 93bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks } 94bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 95593308259bbd335eda9c5280cdd1f7883c746211Julia Lawall size = resource_size(res); 96bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 97bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->ioarea = request_mem_region(res->start, size, dev->name); 98bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks if (pd->ioarea == NULL) { 99bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks dev_err(&dev->dev, "cannot request IO\n"); 100bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks ret = -ENXIO; 101bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks goto err; 102bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks } 103bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 104bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->reg = ioremap(res->start, size); 105bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks if (pd->reg == NULL) { 106bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks dev_err(&dev->dev, "cannot map IO\n"); 107bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks ret = -ENXIO; 108bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks goto err_res; 109bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks } 110bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 111bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks /* setup the private data */ 112bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 113bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->adap.owner = THIS_MODULE; 114bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->adap.algo_data = &pd->bit; 115bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->adap.dev.parent = &dev->dev; 116bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 117bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks strlcpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name)); 118bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 119bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.data = pd; 120bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.setsda = simtec_i2c_setsda; 121bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.setscl = simtec_i2c_setscl; 122bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.getsda = simtec_i2c_getsda; 123bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.getscl = simtec_i2c_getscl; 124bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.timeout = HZ; 125bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks pd->bit.udelay = 20; 126bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 127bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks ret = i2c_bit_add_bus(&pd->adap); 128bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks if (ret) 129bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks goto err_all; 130bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 131bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks return 0; 132bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 133bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks err_all: 134bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks iounmap(pd->reg); 135bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 136bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks err_res: 137bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks release_resource(pd->ioarea); 138bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks kfree(pd->ioarea); 139bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 140bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks err: 141bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks kfree(pd); 142bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks return ret; 143bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks} 144bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 145bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic int simtec_i2c_remove(struct platform_device *dev) 146bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks{ 147bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks struct simtec_i2c_data *pd = platform_get_drvdata(dev); 148bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 149bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks i2c_del_adapter(&pd->adap); 150bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 151bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks iounmap(pd->reg); 152bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks release_resource(pd->ioarea); 153bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks kfree(pd->ioarea); 154bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks kfree(pd); 155bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 156bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks return 0; 157bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks} 158bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 159bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks/* device driver */ 160bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 161bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooksstatic struct platform_driver simtec_i2c_driver = { 162bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks .driver = { 163bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks .name = "simtec-i2c", 164bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks .owner = THIS_MODULE, 165bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks }, 166bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks .probe = simtec_i2c_probe, 167bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks .remove = simtec_i2c_remove, 168bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks}; 169bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 170a3664b51c783aaa0dde1c95334d1a670d6d54590Axel Linmodule_platform_driver(simtec_i2c_driver); 171bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen Dooks 172bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen DooksMODULE_DESCRIPTION("Simtec Generic I2C Bus driver"); 173bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen DooksMODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); 174bcda9f1eb0de0e1108c8b2765e5b7afa0dfb6c9fBen DooksMODULE_LICENSE("GPL"); 175a3664b51c783aaa0dde1c95334d1a670d6d54590Axel LinMODULE_ALIAS("platform:simtec-i2c"); 176