target/linux/generic-2.6/patches-2.6.23/922-w1_gpio_driver_backport.patch

   1 --- a/drivers/w1/masters/Kconfig
   2 +++ b/drivers/w1/masters/Kconfig
   3 @@ -42,5 +42,15 @@
   4           in HP iPAQ devices like h5xxx, h2200, and ASIC3-based like
   5           hx4700.
   6
   7 +config W1_MASTER_GPIO
   8 +       tristate "GPIO 1-wire busmaster"
   9 +       depends on GENERIC_GPIO
  10 +       help
  11 +         Say Y here if you want to communicate with your 1-wire devices using
  12 +         GPIO pins. This driver uses the GPIO API to control the wire.
  13 +
  14 +         This support is also available as a module.  If so, the module
  15 +         will be called w1-gpio.ko.
  16 +
  17  endmenu
  18
  19 --- a/drivers/w1/masters/Makefile
  20 +++ b/drivers/w1/masters/Makefile
  21 @@ -6,3 +6,4 @@
  22  obj-$(CONFIG_W1_MASTER_DS2490)         += ds2490.o
  23  obj-$(CONFIG_W1_MASTER_DS2482)         += ds2482.o
  24  obj-$(CONFIG_W1_MASTER_DS1WM)          += ds1wm.o
  25 +obj-$(CONFIG_W1_MASTER_GPIO)           += w1-gpio.o
  26 --- /dev/null
  27 +++ b/drivers/w1/masters/w1-gpio.c
  28 @@ -0,0 +1,124 @@
  29 +/*
  30 + * w1-gpio - GPIO w1 bus master driver
  31 + *
  32 + * Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
  33 + *
  34 + * This program is free software; you can redistribute it and/or modify
  35 + * it under the terms of the GNU General Public License version 2
  36 + * as published by the Free Software Foundation.
  37 + */
  38 +
  39 +#include <linux/init.h>
  40 +#include <linux/module.h>
  41 +#include <linux/platform_device.h>
  42 +#include <linux/w1-gpio.h>
  43 +
  44 +#include "../w1.h"
  45 +#include "../w1_int.h"
  46 +
  47 +#include <asm/gpio.h>
  48 +
  49 +static void w1_gpio_write_bit_dir(void *data, u8 bit)
  50 +{
  51 +       struct w1_gpio_platform_data *pdata = data;
  52 +
  53 +       if (bit)
  54 +               gpio_direction_input(pdata->pin);
  55 +       else
  56 +               gpio_direction_output(pdata->pin, 0);
  57 +}
  58 +
  59 +static void w1_gpio_write_bit_val(void *data, u8 bit)
  60 +{
  61 +       struct w1_gpio_platform_data *pdata = data;
  62 +
  63 +       gpio_set_value(pdata->pin, bit);
  64 +}
  65 +
  66 +static u8 w1_gpio_read_bit(void *data)
  67 +{
  68 +       struct w1_gpio_platform_data *pdata = data;
  69 +
  70 +       return gpio_get_value(pdata->pin);
  71 +}
  72 +
  73 +static int __init w1_gpio_probe(struct platform_device *pdev)
  74 +{
  75 +       struct w1_bus_master *master;
  76 +       struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
  77 +       int err;
  78 +
  79 +       if (!pdata)
  80 +               return -ENXIO;
  81 +
  82 +       master = kzalloc(sizeof(struct w1_bus_master), GFP_KERNEL);
  83 +       if (!master)
  84 +               return -ENOMEM;
  85 +
  86 +       err = gpio_request(pdata->pin, "w1");
  87 +       if (err)
  88 +               goto free_master;
  89 +
  90 +       master->data = pdata;
  91 +       master->read_bit = w1_gpio_read_bit;
  92 +
  93 +       if (pdata->is_open_drain) {
  94 +               gpio_direction_output(pdata->pin, 1);
  95 +               master->write_bit = w1_gpio_write_bit_val;
  96 +       } else {
  97 +               gpio_direction_input(pdata->pin);
  98 +               master->write_bit = w1_gpio_write_bit_dir;
  99 +       }
 100 +
 101 +       err = w1_add_master_device(master);
 102 +       if (err)
 103 +               goto free_gpio;
 104 +
 105 +       platform_set_drvdata(pdev, master);
 106 +
 107 +       return 0;
 108 +
 109 + free_gpio:
 110 +       gpio_free(pdata->pin);
 111 + free_master:
 112 +       kfree(master);
 113 +
 114 +       return err;
 115 +}
 116 +
 117 +static int __exit w1_gpio_remove(struct platform_device *pdev)
 118 +{
 119 +       struct w1_bus_master *master = platform_get_drvdata(pdev);
 120 +       struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
 121 +
 122 +       w1_remove_master_device(master);
 123 +       gpio_free(pdata->pin);
 124 +       kfree(master);
 125 +
 126 +       return 0;
 127 +}
 128 +
 129 +static struct platform_driver w1_gpio_driver = {
 130 +       .driver = {
 131 +               .name   = "w1-gpio",
 132 +               .owner  = THIS_MODULE,
 133 +       },
 134 +       .remove = __exit_p(w1_gpio_remove),
 135 +};
 136 +
 137 +static int __init w1_gpio_init(void)
 138 +{
 139 +       return platform_driver_probe(&w1_gpio_driver, w1_gpio_probe);
 140 +}
 141 +
 142 +static void __exit w1_gpio_exit(void)
 143 +{
 144 +       platform_driver_unregister(&w1_gpio_driver);
 145 +}
 146 +
 147 +module_init(w1_gpio_init);
 148 +module_exit(w1_gpio_exit);
 149 +
 150 +MODULE_DESCRIPTION("GPIO w1 bus master driver");
 151 +MODULE_AUTHOR("Ville Syrjala <syrjala@sci.fi>");
 152 +MODULE_LICENSE("GPL");
 153 --- /dev/null
 154 +++ b/include/linux/w1-gpio.h
 155 @@ -0,0 +1,23 @@
 156 +/*
 157 + * w1-gpio interface to platform code
 158 + *
 159 + * Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
 160 + *
 161 + * This program is free software; you can redistribute it and/or modify
 162 + * it under the terms of the GNU General Public License version 2
 163 + * as published by the Free Software Foundation.
 164 + */
 165 +#ifndef _LINUX_W1_GPIO_H
 166 +#define _LINUX_W1_GPIO_H
 167 +
 168 +/**
 169 + * struct w1_gpio_platform_data - Platform-dependent data for w1-gpio
 170 + * @pin: GPIO pin to use
 171 + * @is_open_drain: GPIO pin is configured as open drain
 172 + */
 173 +struct w1_gpio_platform_data {
 174 +       unsigned int pin;
 175 +       unsigned int is_open_drain:1;
 176 +};
 177 +
 178 +#endif /* _LINUX_W1_GPIO_H */