target/linux/ixp4xx/patches-2.6.27/295-latch_led_driver.patch

   1 --- a/drivers/leds/Kconfig
   2 +++ b/drivers/leds/Kconfig
   3 @@ -125,6 +125,12 @@ config LEDS_GPIO
   4           outputs. To be useful the particular board must have LEDs
   5           and they must be connected to the GPIO lines.
   6
   7 +config LEDS_LATCH
   8 +       tristate "LED Support for Memory Latched LEDs"
   9 +       depends on LEDS_CLASS
  10 +       help
  11 +               -- To Do --
  12 +
  13  config LEDS_CM_X270
  14         tristate "LED Support for the CM-X270 LEDs"
  15         depends on LEDS_CLASS && MACH_ARMCORE
  16 --- /dev/null
  17 +++ b/drivers/leds/leds-latch.c
  18 @@ -0,0 +1,149 @@
  19 +/*
  20 + * LEDs driver for Memory Latched Devices
  21 + *
  22 + * Copyright (C) 2008 Gateworks Corp.
  23 + * Chris Lang <clang@gateworks.com>
  24 + *
  25 + * This program is free software; you can redistribute it and/or modify
  26 + * it under the terms of the GNU General Public License version 2 as
  27 + * published by the Free Software Foundation.
  28 + *
  29 + */
  30 +#include <linux/kernel.h>
  31 +#include <linux/init.h>
  32 +#include <linux/platform_device.h>
  33 +#include <linux/leds.h>
  34 +#include <linux/workqueue.h>
  35 +#include <asm/io.h>
  36 +#include <linux/spinlock.h>
  37 +
  38 +static unsigned int mem_keep = 0xFF;
  39 +static spinlock_t mem_lock;
  40 +static unsigned char *iobase;
  41 +
  42 +struct latch_led_data {
  43 +       struct led_classdev cdev;
  44 +       struct work_struct work;
  45 +       u8 new_level;
  46 +       u8 bit;
  47 +       void (*set_led)(u8 bit, enum led_brightness value);
  48 +};
  49 +
  50 +static void latch_set_led(u8 bit, enum led_brightness value)
  51 +{
  52 +       if (value == LED_OFF)
  53 +               mem_keep |= (0x1 << bit);
  54 +       else
  55 +               mem_keep &= ~(0x1 << bit);
  56 +
  57 +       writeb(mem_keep, iobase);
  58 +}
  59 +
  60 +static void latch_led_set(struct led_classdev *led_cdev,
  61 +       enum led_brightness value)
  62 +{
  63 +       struct latch_led_data *led_dat =
  64 +               container_of(led_cdev, struct latch_led_data, cdev);
  65 +
  66 +       spin_lock(mem_lock);
  67 +
  68 +       led_dat->set_led(led_dat->bit, value);
  69 +
  70 +       spin_unlock(mem_lock);
  71 +}
  72 +
  73 +static int latch_led_probe(struct platform_device *pdev)
  74 +{
  75 +       struct latch_led_platform_data *pdata = pdev->dev.platform_data;
  76 +       struct latch_led *cur_led;
  77 +       struct latch_led_data *leds_data, *led_dat;
  78 +       int i, ret = 0;
  79 +
  80 +       if (!pdata)
  81 +               return -EBUSY;
  82 +
  83 +       leds_data = kzalloc(sizeof(struct latch_led_data) * pdata->num_leds,
  84 +                               GFP_KERNEL);
  85 +       if (!leds_data)
  86 +               return -ENOMEM;
  87 +
  88 +       for (i = 0; i < pdata->num_leds; i++) {
  89 +               cur_led = &pdata->leds[i];
  90 +               led_dat = &leds_data[i];
  91 +
  92 +               led_dat->cdev.name = cur_led->name;
  93 +               led_dat->cdev.default_trigger = cur_led->default_trigger;
  94 +               led_dat->cdev.brightness_set = latch_led_set;
  95 +               led_dat->cdev.brightness = LED_OFF;
  96 +               led_dat->bit = cur_led->bit;
  97 +               led_dat->set_led = pdata->set_led ? pdata->set_led : latch_set_led;
  98 +
  99 +               ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
 100 +               if (ret < 0) {
 101 +                       goto err;
 102 +               }
 103 +       }
 104 +
 105 +       if (!pdata->set_led) {
 106 +               iobase = ioremap_nocache(pdata->mem, 0x1000);
 107 +               writeb(0xFF, iobase);
 108 +       }
 109 +       platform_set_drvdata(pdev, leds_data);
 110 +
 111 +       return 0;
 112 +
 113 +err:
 114 +       if (i > 0) {
 115 +               for (i = i - 1; i >= 0; i--) {
 116 +                       led_classdev_unregister(&leds_data[i].cdev);
 117 +               }
 118 +       }
 119 +
 120 +       kfree(leds_data);
 121 +
 122 +       return ret;
 123 +}
 124 +
 125 +static int __devexit latch_led_remove(struct platform_device *pdev)
 126 +{
 127 +       int i;
 128 +       struct latch_led_platform_data *pdata = pdev->dev.platform_data;
 129 +       struct latch_led_data *leds_data;
 130 +
 131 +       leds_data = platform_get_drvdata(pdev);
 132 +
 133 +       for (i = 0; i < pdata->num_leds; i++) {
 134 +               led_classdev_unregister(&leds_data[i].cdev);
 135 +               cancel_work_sync(&leds_data[i].work);
 136 +       }
 137 +
 138 +       kfree(leds_data);
 139 +
 140 +       return 0;
 141 +}
 142 +
 143 +static struct platform_driver latch_led_driver = {
 144 +       .probe          = latch_led_probe,
 145 +       .remove         = __devexit_p(latch_led_remove),
 146 +       .driver         = {
 147 +               .name   = "leds-latch",
 148 +               .owner  = THIS_MODULE,
 149 +       },
 150 +};
 151 +
 152 +static int __init latch_led_init(void)
 153 +{
 154 +       return platform_driver_register(&latch_led_driver);
 155 +}
 156 +
 157 +static void __exit latch_led_exit(void)
 158 +{
 159 +       platform_driver_unregister(&latch_led_driver);
 160 +}
 161 +
 162 +module_init(latch_led_init);
 163 +module_exit(latch_led_exit);
 164 +
 165 +MODULE_AUTHOR("Chris Lang <clang@gateworks.com>");
 166 +MODULE_DESCRIPTION("Latch LED driver");
 167 +MODULE_LICENSE("GPL");
 168 --- a/drivers/leds/Makefile
 169 +++ b/drivers/leds/Makefile
 170 @@ -19,6 +19,7 @@ obj-$(CONFIG_LEDS_COBALT_QUBE)                += leds-
 171  obj-$(CONFIG_LEDS_COBALT_RAQ)          += leds-cobalt-raq.o
 172  obj-$(CONFIG_LEDS_PCA9532)             += leds-pca9532.o
 173  obj-$(CONFIG_LEDS_GPIO)                        += leds-gpio.o
 174 +obj-$(CONFIG_LEDS_LATCH)     += leds-latch.o
 175  obj-$(CONFIG_LEDS_CM_X270)              += leds-cm-x270.o
 176  obj-$(CONFIG_LEDS_CLEVO_MAIL)          += leds-clevo-mail.o
 177  obj-$(CONFIG_LEDS_HP6XX)               += leds-hp6xx.o
 178 --- a/include/linux/leds.h
 179 +++ b/include/linux/leds.h
 180 @@ -148,5 +148,19 @@ struct gpio_led_platform_data {
 181                                         unsigned long *delay_off);
 182  };
 183
 184 +/* For the leds-latch driver */
 185 +struct latch_led {
 186 +       const char *name;
 187 +       char *default_trigger;
 188 +       unsigned  bit;
 189 +};
 190 +
 191 +struct latch_led_platform_data {
 192 +       int     num_leds;
 193 +       u32     mem;
 194 +       struct latch_led *leds;
 195 +       void    (*set_led)(u8 bit, enum led_brightness value);
 196 +};
 197 +
 198
 199  #endif         /* __LINUX_LEDS_H_INCLUDED */