183 lines
4.3 KiB
C
183 lines
4.3 KiB
C
/*
|
|
* Custom GPIO-based W1 driver
|
|
*
|
|
* Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
|
|
* Copyright (C) 2008 Bifferos <bifferos at yahoo.co.uk>
|
|
*
|
|
* 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.
|
|
*
|
|
* ---------------------------------------------------------------------------
|
|
*
|
|
* The behaviour of this driver can be altered by setting some parameters
|
|
* from the insmod command line.
|
|
*
|
|
* The following parameters are adjustable:
|
|
*
|
|
* bus0 These four arguments must be arrays of
|
|
* bus1 3 unsigned integers as follows:
|
|
* bus2
|
|
* bus3 <id>,<pin>,<od>
|
|
*
|
|
* where:
|
|
*
|
|
* <id> ID to used as device_id for the corresponding bus (required)
|
|
* <sda> GPIO pin ID of data pin (required)
|
|
* <od> Pin is configured as open drain.
|
|
*
|
|
* See include/w1-gpio.h for more information about the parameters.
|
|
*
|
|
* If this driver is built into the kernel, you can use the following kernel
|
|
* command line parameters, with the same values as the corresponding module
|
|
* parameters listed above:
|
|
*
|
|
* w1-gpio-custom.bus0
|
|
* w1-gpio-custom.bus1
|
|
* w1-gpio-custom.bus2
|
|
* w1-gpio-custom.bus3
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
#include <linux/w1-gpio.h>
|
|
|
|
#define DRV_NAME "w1-gpio-custom"
|
|
#define DRV_DESC "Custom GPIO-based W1 driver"
|
|
#define DRV_VERSION "0.1.0"
|
|
|
|
#define PFX DRV_NAME ": "
|
|
|
|
#define BUS_PARAM_ID 0
|
|
#define BUS_PARAM_PIN 1
|
|
#define BUS_PARAM_OD 2
|
|
|
|
#define BUS_PARAM_REQUIRED 3
|
|
#define BUS_PARAM_COUNT 3
|
|
#define BUS_COUNT_MAX 4
|
|
|
|
static unsigned int bus0[BUS_PARAM_COUNT] __initdata;
|
|
static unsigned int bus1[BUS_PARAM_COUNT] __initdata;
|
|
static unsigned int bus2[BUS_PARAM_COUNT] __initdata;
|
|
static unsigned int bus3[BUS_PARAM_COUNT] __initdata;
|
|
|
|
static unsigned int bus_nump[BUS_COUNT_MAX] __initdata;
|
|
|
|
#define BUS_PARM_DESC " config -> id,pin,od"
|
|
|
|
module_param_array(bus0, uint, &bus_nump[0], 0);
|
|
MODULE_PARM_DESC(bus0, "bus0" BUS_PARM_DESC);
|
|
module_param_array(bus1, uint, &bus_nump[1], 0);
|
|
MODULE_PARM_DESC(bus1, "bus1" BUS_PARM_DESC);
|
|
module_param_array(bus2, uint, &bus_nump[2], 0);
|
|
MODULE_PARM_DESC(bus2, "bus2" BUS_PARM_DESC);
|
|
module_param_array(bus3, uint, &bus_nump[3], 0);
|
|
MODULE_PARM_DESC(bus3, "bus3" BUS_PARM_DESC);
|
|
|
|
static struct platform_device *devices[BUS_COUNT_MAX];
|
|
static unsigned int nr_devices;
|
|
|
|
static void w1_gpio_custom_cleanup(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_devices; i++)
|
|
if (devices[i])
|
|
platform_device_unregister(devices[i]);
|
|
}
|
|
|
|
static int __init w1_gpio_custom_add_one(unsigned int id, unsigned int *params)
|
|
{
|
|
struct platform_device *pdev;
|
|
struct w1_gpio_platform_data pdata;
|
|
int err;
|
|
|
|
if (!bus_nump[id])
|
|
return 0;
|
|
|
|
if (bus_nump[id] < BUS_PARAM_REQUIRED) {
|
|
printk(KERN_ERR PFX "not enough parameters for bus%d\n", id);
|
|
err = -EINVAL;
|
|
goto err;
|
|
}
|
|
|
|
pdev = platform_device_alloc("w1-gpio", params[BUS_PARAM_ID]);
|
|
if (!pdev) {
|
|
err = -ENOMEM;
|
|
goto err;
|
|
}
|
|
|
|
devices[nr_devices++] = pdev;
|
|
|
|
pdata.pin = params[BUS_PARAM_PIN];
|
|
pdata.is_open_drain = params[BUS_PARAM_OD] ? 1:0;
|
|
|
|
err = platform_device_add_data(pdev, &pdata, sizeof(pdata));
|
|
if (err)
|
|
goto err;
|
|
|
|
err = platform_device_register(pdev);
|
|
if (err)
|
|
goto err;
|
|
|
|
return 0;
|
|
|
|
err:
|
|
return err;
|
|
}
|
|
|
|
static int __init w1_gpio_custom_probe(void)
|
|
{
|
|
int err;
|
|
|
|
nr_devices = 0;
|
|
printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
|
|
|
|
err = w1_gpio_custom_add_one(0, bus0);
|
|
if (err) goto err;
|
|
|
|
err = w1_gpio_custom_add_one(1, bus1);
|
|
if (err) goto err;
|
|
|
|
err = w1_gpio_custom_add_one(2, bus2);
|
|
if (err) goto err;
|
|
|
|
err = w1_gpio_custom_add_one(3, bus3);
|
|
if (err) goto err;
|
|
|
|
if (!nr_devices) {
|
|
printk(KERN_ERR PFX "no bus parameter(s) specified\n");
|
|
err = -ENODEV;
|
|
goto err;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err:
|
|
w1_gpio_custom_cleanup();
|
|
return err;
|
|
}
|
|
|
|
#ifdef MODULE
|
|
static int __init w1_gpio_custom_init(void)
|
|
{
|
|
return w1_gpio_custom_probe();
|
|
}
|
|
module_init(w1_gpio_custom_init);
|
|
|
|
static void __exit w1_gpio_custom_exit(void)
|
|
{
|
|
w1_gpio_custom_cleanup();
|
|
}
|
|
module_exit(w1_gpio_custom_exit);
|
|
#else
|
|
subsys_initcall(w1_gpio_custom_probe);
|
|
#endif /* MODULE*/
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Bifferos <bifferos at yahoo.co.uk >");
|
|
MODULE_DESCRIPTION(DRV_DESC);
|
|
MODULE_VERSION(DRV_VERSION);
|