--- /dev/null
+/*
+ * Support for the Extra GPIOs on the Sharp SL-C1000 (Akita)
+ * (uses a Maxim MAX7310 8 Port IO Expander)
+ *
+ * Copyright 2005 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <richard@openedhand.com>
+ *
+ * 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/init.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <asm/arch/akita.h>
+
+/* MAX7310 Regiser Map */
+#define MAX7310_INPUT 0x00
+#define MAX7310_OUTPUT 0x01
+#define MAX7310_POLINV 0x02
+#define MAX7310_IODIR 0x03 /* 1 = Input, 0 = Output */
+#define MAX7310_TIMEOUT 0x04
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { 0x18, I2C_CLIENT_END };
+
+/* I2C Magic */
+I2C_CLIENT_INSMOD;
+
+static int max7310_write(struct i2c_client *client, int address, int data);
+static struct i2c_client max7310_template;
+static void akita_ioexp_work(void *private_);
+
+static struct device *akita_ioexp_device;
+static unsigned char ioexp_output_value = AKITA_IOEXP_IO_OUT;
+DECLARE_WORK(akita_ioexp, akita_ioexp_work, NULL);
+
+
+/*
+ * MAX7310 Access
+ */
+static int max7310_config(struct device *dev, int iomode, int polarity)
+{
+ int ret;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ ret = max7310_write(client, MAX7310_POLINV, polarity);
+ if (ret < 0)
+ return ret;
+ ret = max7310_write(client, MAX7310_IODIR, iomode);
+ return ret;
+}
+
+static int max7310_set_ouputs(struct device *dev, int outputs)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+
+ return max7310_write(client, MAX7310_OUTPUT, outputs);
+}
+
+/*
+ * I2C Functions
+ */
+static int max7310_write(struct i2c_client *client, int address, int value)
+{
+ u8 data[2];
+
+ data[0] = address & 0xff;
+ data[1] = value & 0xff;
+
+ if (i2c_master_send(client, data, 2) == 2)
+ return 0;
+ return -1;
+}
+
+static int max7310_detect(struct i2c_adapter *adapter, int address, int kind)
+{
+ struct i2c_client *new_client;
+ int err;
+
+ if (!(new_client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL)))
+ return -ENOMEM;
+
+ max7310_template.adapter = adapter;
+ max7310_template.addr = address;
+
+ memcpy(new_client, &max7310_template, sizeof(struct i2c_client));
+
+ if ((err = i2c_attach_client(new_client))) {
+ kfree(new_client);
+ return err;
+ }
+
+ max7310_config(&new_client->dev, AKITA_IOEXP_IO_DIR, 0);
+ akita_ioexp_device = &new_client->dev;
+ schedule_work(&akita_ioexp);
+
+ return 0;
+}
+
+static int max7310_attach_adapter(struct i2c_adapter *adapter)
+{
+ return i2c_probe(adapter, &addr_data, max7310_detect);
+}
+
+static int max7310_detach_client(struct i2c_client *client)
+{
+ int err;
+
+ akita_ioexp_device = NULL;
+
+ if ((err = i2c_detach_client(client)))
+ return err;
+
+ kfree(client);
+ return 0;
+}
+
+static struct i2c_driver max7310_i2c_driver = {
+ .owner = THIS_MODULE,
+ .name = "akita-max7310",
+ .id = I2C_DRIVERID_AKITAIOEXP,
+ .flags = I2C_DF_NOTIFY,
+ .attach_adapter = max7310_attach_adapter,
+ .detach_client = max7310_detach_client,
+};
+
+static struct i2c_client max7310_template = {
+ name: "akita-max7310",
+ flags: I2C_CLIENT_ALLOW_USE,
+ driver: &max7310_i2c_driver,
+};
+
+void akita_set_ioexp(struct device *dev, unsigned char bit)
+{
+ ioexp_output_value |= bit;
+
+ if (akita_ioexp_device)
+ schedule_work(&akita_ioexp);
+ return;
+}
+
+void akita_reset_ioexp(struct device *dev, unsigned char bit)
+{
+ ioexp_output_value &= ~bit;
+
+ if (akita_ioexp_device)
+ schedule_work(&akita_ioexp);
+ return;
+}
+
+EXPORT_SYMBOL(akita_set_ioexp);
+EXPORT_SYMBOL(akita_reset_ioexp);
+
+static void akita_ioexp_work(void *private_)
+{
+ if (akita_ioexp_device)
+ max7310_set_ouputs(akita_ioexp_device, ioexp_output_value);
+}
+
+
+#ifdef CONFIG_PM
+static int akita_ioexp_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ flush_scheduled_work();
+ return 0;
+}
+
+static int akita_ioexp_resume(struct platform_device *pdev)
+{
+ schedule_work(&akita_ioexp);
+ return 0;
+}
+#else
+#define akita_ioexp_suspend NULL
+#define akita_ioexp_resume NULL
+#endif
+
+static int __init akita_ioexp_probe(struct platform_device *pdev)
+{
+ return i2c_add_driver(&max7310_i2c_driver);
+}
+
+static int akita_ioexp_remove(struct platform_device *pdev)
+{
+ i2c_del_driver(&max7310_i2c_driver);
+ return 0;
+}
+
+static struct platform_driver akita_ioexp_driver = {
+ .probe = akita_ioexp_probe,
+ .remove = akita_ioexp_remove,
+ .suspend = akita_ioexp_suspend,
+ .resume = akita_ioexp_resume,
+ .driver = {
+ .name = "akita-ioexp",
+ },
+};
+
+static int __init akita_ioexp_init(void)
+{
+ return platform_driver_register(&akita_ioexp_driver);
+}
+
+static void __exit akita_ioexp_exit(void)
+{
+ platform_driver_unregister(&akita_ioexp_driver);
+}
+
+MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
+MODULE_DESCRIPTION("Akita IO-Expander driver");
+MODULE_LICENSE("GPL");
+
+fs_initcall(akita_ioexp_init);
+module_exit(akita_ioexp_exit);
+
projects / linux-2.6 / commitdiff