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2504ba9f59
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 53 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.904365654@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
157 lines
3.1 KiB
C
157 lines
3.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2005 Simtec Electronics
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* Ben Dooks <ben@simtec.co.uk>
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*
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* Simtec Generic I2C Controller
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/delay.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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#include <linux/io.h>
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#include <linux/i2c.h>
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#include <linux/i2c-algo-bit.h>
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struct simtec_i2c_data {
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struct resource *ioarea;
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void __iomem *reg;
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struct i2c_adapter adap;
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struct i2c_algo_bit_data bit;
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};
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#define CMD_SET_SDA (1<<2)
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#define CMD_SET_SCL (1<<3)
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#define STATE_SDA (1<<0)
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#define STATE_SCL (1<<1)
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/* i2c bit-bus functions */
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static void simtec_i2c_setsda(void *pw, int state)
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{
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struct simtec_i2c_data *pd = pw;
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writeb(CMD_SET_SDA | (state ? STATE_SDA : 0), pd->reg);
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}
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static void simtec_i2c_setscl(void *pw, int state)
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{
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struct simtec_i2c_data *pd = pw;
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writeb(CMD_SET_SCL | (state ? STATE_SCL : 0), pd->reg);
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}
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static int simtec_i2c_getsda(void *pw)
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{
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struct simtec_i2c_data *pd = pw;
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return readb(pd->reg) & STATE_SDA ? 1 : 0;
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}
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static int simtec_i2c_getscl(void *pw)
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{
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struct simtec_i2c_data *pd = pw;
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return readb(pd->reg) & STATE_SCL ? 1 : 0;
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}
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/* device registration */
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static int simtec_i2c_probe(struct platform_device *dev)
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{
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struct simtec_i2c_data *pd;
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struct resource *res;
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int size;
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int ret;
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pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL);
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if (pd == NULL)
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return -ENOMEM;
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platform_set_drvdata(dev, pd);
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res = platform_get_resource(dev, IORESOURCE_MEM, 0);
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if (res == NULL) {
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dev_err(&dev->dev, "cannot find IO resource\n");
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ret = -ENOENT;
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goto err;
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}
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size = resource_size(res);
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pd->ioarea = request_mem_region(res->start, size, dev->name);
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if (pd->ioarea == NULL) {
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dev_err(&dev->dev, "cannot request IO\n");
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ret = -ENXIO;
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goto err;
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}
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pd->reg = ioremap(res->start, size);
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if (pd->reg == NULL) {
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dev_err(&dev->dev, "cannot map IO\n");
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ret = -ENXIO;
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goto err_res;
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}
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/* setup the private data */
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pd->adap.owner = THIS_MODULE;
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pd->adap.algo_data = &pd->bit;
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pd->adap.dev.parent = &dev->dev;
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strlcpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name));
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pd->bit.data = pd;
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pd->bit.setsda = simtec_i2c_setsda;
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pd->bit.setscl = simtec_i2c_setscl;
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pd->bit.getsda = simtec_i2c_getsda;
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pd->bit.getscl = simtec_i2c_getscl;
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pd->bit.timeout = HZ;
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pd->bit.udelay = 20;
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ret = i2c_bit_add_bus(&pd->adap);
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if (ret)
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goto err_all;
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return 0;
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err_all:
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iounmap(pd->reg);
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err_res:
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release_mem_region(pd->ioarea->start, size);
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err:
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kfree(pd);
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return ret;
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}
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static int simtec_i2c_remove(struct platform_device *dev)
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{
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struct simtec_i2c_data *pd = platform_get_drvdata(dev);
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i2c_del_adapter(&pd->adap);
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iounmap(pd->reg);
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release_mem_region(pd->ioarea->start, resource_size(pd->ioarea));
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kfree(pd);
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return 0;
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}
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/* device driver */
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static struct platform_driver simtec_i2c_driver = {
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.driver = {
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.name = "simtec-i2c",
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},
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.probe = simtec_i2c_probe,
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.remove = simtec_i2c_remove,
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};
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module_platform_driver(simtec_i2c_driver);
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MODULE_DESCRIPTION("Simtec Generic I2C Bus driver");
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MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("platform:simtec-i2c");
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