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137 lines
3.1 KiB
137 lines
3.1 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* i2c-versatile.c |
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* |
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* Copyright (C) 2006 ARM Ltd. |
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* written by Russell King, Deep Blue Solutions Ltd. |
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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/i2c.h> |
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#include <linux/i2c-algo-bit.h> |
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#include <linux/init.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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#define I2C_CONTROL 0x00 |
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#define I2C_CONTROLS 0x00 |
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#define I2C_CONTROLC 0x04 |
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#define SCL (1 << 0) |
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#define SDA (1 << 1) |
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struct i2c_versatile { |
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struct i2c_adapter adap; |
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struct i2c_algo_bit_data algo; |
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void __iomem *base; |
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}; |
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static void i2c_versatile_setsda(void *data, int state) |
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{ |
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struct i2c_versatile *i2c = data; |
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writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC)); |
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} |
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static void i2c_versatile_setscl(void *data, int state) |
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{ |
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struct i2c_versatile *i2c = data; |
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writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC)); |
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} |
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static int i2c_versatile_getsda(void *data) |
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{ |
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struct i2c_versatile *i2c = data; |
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return !!(readl(i2c->base + I2C_CONTROL) & SDA); |
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} |
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static int i2c_versatile_getscl(void *data) |
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{ |
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struct i2c_versatile *i2c = data; |
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return !!(readl(i2c->base + I2C_CONTROL) & SCL); |
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} |
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static const struct i2c_algo_bit_data i2c_versatile_algo = { |
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.setsda = i2c_versatile_setsda, |
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.setscl = i2c_versatile_setscl, |
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.getsda = i2c_versatile_getsda, |
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.getscl = i2c_versatile_getscl, |
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.udelay = 30, |
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.timeout = HZ, |
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}; |
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static int i2c_versatile_probe(struct platform_device *dev) |
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{ |
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struct i2c_versatile *i2c; |
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struct resource *r; |
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int ret; |
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i2c = devm_kzalloc(&dev->dev, sizeof(struct i2c_versatile), GFP_KERNEL); |
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if (!i2c) |
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return -ENOMEM; |
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r = platform_get_resource(dev, IORESOURCE_MEM, 0); |
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i2c->base = devm_ioremap_resource(&dev->dev, r); |
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if (IS_ERR(i2c->base)) |
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return PTR_ERR(i2c->base); |
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writel(SCL | SDA, i2c->base + I2C_CONTROLS); |
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i2c->adap.owner = THIS_MODULE; |
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strlcpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name)); |
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i2c->adap.algo_data = &i2c->algo; |
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i2c->adap.dev.parent = &dev->dev; |
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i2c->adap.dev.of_node = dev->dev.of_node; |
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i2c->algo = i2c_versatile_algo; |
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i2c->algo.data = i2c; |
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i2c->adap.nr = dev->id; |
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ret = i2c_bit_add_numbered_bus(&i2c->adap); |
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if (ret < 0) |
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return ret; |
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platform_set_drvdata(dev, i2c); |
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return 0; |
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} |
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static int i2c_versatile_remove(struct platform_device *dev) |
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{ |
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struct i2c_versatile *i2c = platform_get_drvdata(dev); |
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i2c_del_adapter(&i2c->adap); |
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return 0; |
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} |
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static const struct of_device_id i2c_versatile_match[] = { |
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{ .compatible = "arm,versatile-i2c", }, |
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{}, |
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}; |
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MODULE_DEVICE_TABLE(of, i2c_versatile_match); |
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static struct platform_driver i2c_versatile_driver = { |
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.probe = i2c_versatile_probe, |
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.remove = i2c_versatile_remove, |
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.driver = { |
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.name = "versatile-i2c", |
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.of_match_table = i2c_versatile_match, |
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}, |
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}; |
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static int __init i2c_versatile_init(void) |
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{ |
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return platform_driver_register(&i2c_versatile_driver); |
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} |
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static void __exit i2c_versatile_exit(void) |
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{ |
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platform_driver_unregister(&i2c_versatile_driver); |
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} |
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subsys_initcall(i2c_versatile_init); |
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module_exit(i2c_versatile_exit); |
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MODULE_DESCRIPTION("ARM Versatile I2C bus driver"); |
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MODULE_LICENSE("GPL"); |
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MODULE_ALIAS("platform:versatile-i2c");
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