diff options
Diffstat (limited to 'arch/arm/mach-pxa/akita-ioexp.c')
| -rw-r--r-- | arch/arm/mach-pxa/akita-ioexp.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/arch/arm/mach-pxa/akita-ioexp.c b/arch/arm/mach-pxa/akita-ioexp.c new file mode 100644 index 000000000000..f6d73cc01f78 --- /dev/null +++ b/arch/arm/mach-pxa/akita-ioexp.c @@ -0,0 +1,223 @@ +/* + * 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); + |