Version:  2.0.40 2.2.26 2.4.37 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19

Linux/drivers/power/reset/vexpress-poweroff.c

  1 /*
  2  * This program is free software; you can redistribute it and/or modify
  3  * it under the terms of the GNU General Public License version 2 as
  4  * published by the Free Software Foundation.
  5  *
  6  * This program is distributed in the hope that it will be useful,
  7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  9  * GNU General Public License for more details.
 10  *
 11  * Copyright (C) 2012 ARM Limited
 12  */
 13 
 14 #include <linux/delay.h>
 15 #include <linux/notifier.h>
 16 #include <linux/of.h>
 17 #include <linux/of_device.h>
 18 #include <linux/platform_device.h>
 19 #include <linux/reboot.h>
 20 #include <linux/stat.h>
 21 #include <linux/vexpress.h>
 22 
 23 static void vexpress_reset_do(struct device *dev, const char *what)
 24 {
 25         int err = -ENOENT;
 26         struct regmap *reg = dev_get_drvdata(dev);
 27 
 28         if (reg) {
 29                 err = regmap_write(reg, 0, 0);
 30                 if (!err)
 31                         mdelay(1000);
 32         }
 33 
 34         dev_emerg(dev, "Unable to %s (%d)\n", what, err);
 35 }
 36 
 37 static struct device *vexpress_power_off_device;
 38 
 39 static void vexpress_power_off(void)
 40 {
 41         vexpress_reset_do(vexpress_power_off_device, "power off");
 42 }
 43 
 44 static struct device *vexpress_restart_device;
 45 
 46 static int vexpress_restart(struct notifier_block *this, unsigned long mode,
 47                              void *cmd)
 48 {
 49         vexpress_reset_do(vexpress_restart_device, "restart");
 50 
 51         return NOTIFY_DONE;
 52 }
 53 
 54 static struct notifier_block vexpress_restart_nb = {
 55         .notifier_call = vexpress_restart,
 56         .priority = 128,
 57 };
 58 
 59 static ssize_t vexpress_reset_active_show(struct device *dev,
 60                 struct device_attribute *attr, char *buf)
 61 {
 62         return sprintf(buf, "%d\n", vexpress_restart_device == dev);
 63 }
 64 
 65 static ssize_t vexpress_reset_active_store(struct device *dev,
 66                 struct device_attribute *attr, const char *buf, size_t count)
 67 {
 68         long value;
 69         int err = kstrtol(buf, 0, &value);
 70 
 71         if (!err && value)
 72                 vexpress_restart_device = dev;
 73 
 74         return err ? err : count;
 75 }
 76 
 77 DEVICE_ATTR(active, S_IRUGO | S_IWUSR, vexpress_reset_active_show,
 78                 vexpress_reset_active_store);
 79 
 80 
 81 enum vexpress_reset_func { FUNC_RESET, FUNC_SHUTDOWN, FUNC_REBOOT };
 82 
 83 static struct of_device_id vexpress_reset_of_match[] = {
 84         {
 85                 .compatible = "arm,vexpress-reset",
 86                 .data = (void *)FUNC_RESET,
 87         }, {
 88                 .compatible = "arm,vexpress-shutdown",
 89                 .data = (void *)FUNC_SHUTDOWN
 90         }, {
 91                 .compatible = "arm,vexpress-reboot",
 92                 .data = (void *)FUNC_REBOOT
 93         },
 94         {}
 95 };
 96 
 97 static int _vexpress_register_restart_handler(struct device *dev)
 98 {
 99         int err;
100 
101         vexpress_restart_device = dev;
102         err = register_restart_handler(&vexpress_restart_nb);
103         if (err) {
104                 dev_err(dev, "cannot register restart handler (err=%d)\n", err);
105                 return err;
106         }
107         device_create_file(dev, &dev_attr_active);
108 
109         return 0;
110 }
111 
112 static int vexpress_reset_probe(struct platform_device *pdev)
113 {
114         enum vexpress_reset_func func;
115         const struct of_device_id *match =
116                         of_match_device(vexpress_reset_of_match, &pdev->dev);
117         struct regmap *regmap;
118         int ret = 0;
119 
120         if (match)
121                 func = (enum vexpress_reset_func)match->data;
122         else
123                 func = pdev->id_entry->driver_data;
124 
125         regmap = devm_regmap_init_vexpress_config(&pdev->dev);
126         if (IS_ERR(regmap))
127                 return PTR_ERR(regmap);
128         dev_set_drvdata(&pdev->dev, regmap);
129 
130         switch (func) {
131         case FUNC_SHUTDOWN:
132                 vexpress_power_off_device = &pdev->dev;
133                 pm_power_off = vexpress_power_off;
134                 break;
135         case FUNC_RESET:
136                 if (!vexpress_restart_device)
137                         ret = _vexpress_register_restart_handler(&pdev->dev);
138                 break;
139         case FUNC_REBOOT:
140                 ret = _vexpress_register_restart_handler(&pdev->dev);
141                 break;
142         };
143 
144         return ret;
145 }
146 
147 static const struct platform_device_id vexpress_reset_id_table[] = {
148         { .name = "vexpress-reset", .driver_data = FUNC_RESET, },
149         { .name = "vexpress-shutdown", .driver_data = FUNC_SHUTDOWN, },
150         { .name = "vexpress-reboot", .driver_data = FUNC_REBOOT, },
151         {}
152 };
153 
154 static struct platform_driver vexpress_reset_driver = {
155         .probe = vexpress_reset_probe,
156         .driver = {
157                 .name = "vexpress-reset",
158                 .of_match_table = vexpress_reset_of_match,
159         },
160         .id_table = vexpress_reset_id_table,
161 };
162 
163 static int __init vexpress_reset_init(void)
164 {
165         return platform_driver_register(&vexpress_reset_driver);
166 }
167 device_initcall(vexpress_reset_init);
168 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us