This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / i2c / busses / i2c-versatile.c

diff --git a/drivers/i2c/busses/i2c-versatile.c b/drivers/i2c/busses/i2c-versatile.c
new file mode 100644 (file)
index 0000000..081d957
--- /dev/null
+++ b/drivers/i2c/busses/i2c-versatile.c
@@ -0,0 +1,153 @@
+/*
+ *  i2c-versatile.c
+ *
+ *  Copyright (C) 2006 ARM Ltd.
+ *  written by Russell King, Deep Blue Solutions Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+
+#include <asm/io.h>
+
+#define I2C_CONTROL    0x00
+#define I2C_CONTROLS   0x00
+#define I2C_CONTROLC   0x04
+#define SCL            (1 << 0)
+#define SDA            (1 << 1)
+
+struct i2c_versatile {
+       struct i2c_adapter       adap;
+       struct i2c_algo_bit_data algo;
+       void __iomem             *base;
+};
+
+static void i2c_versatile_setsda(void *data, int state)
+{
+       struct i2c_versatile *i2c = data;
+
+       writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
+}
+
+static void i2c_versatile_setscl(void *data, int state)
+{
+       struct i2c_versatile *i2c = data;
+
+       writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
+}
+
+static int i2c_versatile_getsda(void *data)
+{
+       struct i2c_versatile *i2c = data;
+       return !!(readl(i2c->base + I2C_CONTROL) & SDA);
+}
+
+static int i2c_versatile_getscl(void *data)
+{
+       struct i2c_versatile *i2c = data;
+       return !!(readl(i2c->base + I2C_CONTROL) & SCL);
+}
+
+static struct i2c_algo_bit_data i2c_versatile_algo = {
+       .setsda = i2c_versatile_setsda,
+       .setscl = i2c_versatile_setscl,
+       .getsda = i2c_versatile_getsda,
+       .getscl = i2c_versatile_getscl,
+       .udelay = 30,
+       .timeout = HZ,
+};
+
+static int i2c_versatile_probe(struct platform_device *dev)
+{
+       struct i2c_versatile *i2c;
+       struct resource *r;
+       int ret;
+
+       r = platform_get_resource(dev, IORESOURCE_MEM, 0);
+       if (!r) {
+               ret = -EINVAL;
+               goto err_out;
+       }
+
+       if (!request_mem_region(r->start, r->end - r->start + 1, "versatile-i2c")) {
+               ret = -EBUSY;
+               goto err_out;
+       }
+
+       i2c = kzalloc(sizeof(struct i2c_versatile), GFP_KERNEL);
+       if (!i2c) {
+               ret = -ENOMEM;
+               goto err_release;
+       }
+
+       i2c->base = ioremap(r->start, r->end - r->start + 1);
+       if (!i2c->base) {
+               ret = -ENOMEM;
+               goto err_free;
+       }
+
+       writel(SCL | SDA, i2c->base + I2C_CONTROLS);
+
+       i2c->adap.owner = THIS_MODULE;
+       strlcpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name));
+       i2c->adap.algo_data = &i2c->algo;
+       i2c->adap.dev.parent = &dev->dev;
+       i2c->algo = i2c_versatile_algo;
+       i2c->algo.data = i2c;
+
+       ret = i2c_bit_add_bus(&i2c->adap);
+       if (ret >= 0) {
+               platform_set_drvdata(dev, i2c);
+               return 0;
+       }
+
+       iounmap(i2c->base);
+ err_free:
+       kfree(i2c);
+ err_release:
+       release_mem_region(r->start, r->end - r->start + 1);
+ err_out:
+       return ret;
+}
+
+static int i2c_versatile_remove(struct platform_device *dev)
+{
+       struct i2c_versatile *i2c = platform_get_drvdata(dev);
+
+       platform_set_drvdata(dev, NULL);
+
+       i2c_del_adapter(&i2c->adap);
+       return 0;
+}
+
+static struct platform_driver i2c_versatile_driver = {
+       .probe          = i2c_versatile_probe,
+       .remove         = i2c_versatile_remove,
+       .driver         = {
+               .name   = "versatile-i2c",
+               .owner  = THIS_MODULE,
+       },
+};
+
+static int __init i2c_versatile_init(void)
+{
+       return platform_driver_register(&i2c_versatile_driver);
+}
+
+static void __exit i2c_versatile_exit(void)
+{
+       platform_driver_unregister(&i2c_versatile_driver);
+}
+
+module_init(i2c_versatile_init);
+module_exit(i2c_versatile_exit);
+
+MODULE_DESCRIPTION("ARM Versatile I2C bus driver");
+MODULE_LICENSE("GPL");