vmscan: count the number of times zone_reclaim() scans and fails
[sfrench/cifs-2.6.git] / samples / firmware_class / firmware_sample_firmware_class.c
1 /*
2  * firmware_sample_firmware_class.c -
3  *
4  * Copyright (c) 2003 Manuel Estrada Sainz
5  *
6  * NOTE: This is just a probe of concept, if you think that your driver would
7  * be well served by this mechanism please contact me first.
8  *
9  * DON'T USE THIS CODE AS IS
10  *
11  */
12
13 #include <linux/device.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/timer.h>
17 #include <linux/slab.h>
18 #include <linux/string.h>
19 #include <linux/firmware.h>
20
21
22 MODULE_AUTHOR("Manuel Estrada Sainz");
23 MODULE_DESCRIPTION("Hackish sample for using firmware class directly");
24 MODULE_LICENSE("GPL");
25
26 static inline struct class_device *to_class_dev(struct kobject *obj)
27 {
28         return container_of(obj, struct class_device, kobj);
29 }
30
31 static inline
32 struct class_device_attribute *to_class_dev_attr(struct attribute *_attr)
33 {
34         return container_of(_attr, struct class_device_attribute, attr);
35 }
36
37 struct firmware_priv {
38         char fw_id[FIRMWARE_NAME_MAX];
39         s32 loading:2;
40         u32 abort:1;
41 };
42
43 static ssize_t firmware_loading_show(struct class_device *class_dev, char *buf)
44 {
45         struct firmware_priv *fw_priv = class_get_devdata(class_dev);
46         return sprintf(buf, "%d\n", fw_priv->loading);
47 }
48
49 static ssize_t firmware_loading_store(struct class_device *class_dev,
50                                       const char *buf, size_t count)
51 {
52         struct firmware_priv *fw_priv = class_get_devdata(class_dev);
53         int prev_loading = fw_priv->loading;
54
55         fw_priv->loading = simple_strtol(buf, NULL, 10);
56
57         switch (fw_priv->loading) {
58         case -1:
59                 /* abort load an panic */
60                 break;
61         case 1:
62                 /* setup load */
63                 break;
64         case 0:
65                 if (prev_loading == 1) {
66                         /* finish load and get the device back to working
67                          * state */
68                 }
69                 break;
70         }
71
72         return count;
73 }
74 static CLASS_DEVICE_ATTR(loading, 0644,
75                          firmware_loading_show, firmware_loading_store);
76
77 static ssize_t firmware_data_read(struct kobject *kobj,
78                                   struct bin_attribute *bin_attr,
79                                   char *buffer, loff_t offset, size_t count)
80 {
81         struct class_device *class_dev = to_class_dev(kobj);
82         struct firmware_priv *fw_priv = class_get_devdata(class_dev);
83
84         /* read from the devices firmware memory */
85
86         return count;
87 }
88 static ssize_t firmware_data_write(struct kobject *kobj,
89                                    struct bin_attribute *bin_attr,
90                                    char *buffer, loff_t offset, size_t count)
91 {
92         struct class_device *class_dev = to_class_dev(kobj);
93         struct firmware_priv *fw_priv = class_get_devdata(class_dev);
94
95         /* write to the devices firmware memory */
96
97         return count;
98 }
99 static struct bin_attribute firmware_attr_data = {
100         .attr = {.name = "data", .mode = 0644},
101         .size = 0,
102         .read = firmware_data_read,
103         .write = firmware_data_write,
104 };
105 static int fw_setup_class_device(struct class_device *class_dev,
106                                  const char *fw_name,
107                                  struct device *device)
108 {
109         int retval;
110         struct firmware_priv *fw_priv;
111
112         fw_priv = kzalloc(sizeof(struct firmware_priv), GFP_KERNEL);
113         if (!fw_priv) {
114                 retval = -ENOMEM;
115                 goto out;
116         }
117
118         memset(class_dev, 0, sizeof(*class_dev));
119
120         strncpy(fw_priv->fw_id, fw_name, FIRMWARE_NAME_MAX);
121         fw_priv->fw_id[FIRMWARE_NAME_MAX-1] = '\0';
122
123         strncpy(class_dev->class_id, device->bus_id, BUS_ID_SIZE);
124         class_dev->class_id[BUS_ID_SIZE-1] = '\0';
125         class_dev->dev = device;
126
127         class_dev->class = &firmware_class;
128         class_set_devdata(class_dev, fw_priv);
129         retval = class_device_register(class_dev);
130         if (retval) {
131                 printk(KERN_ERR "%s: class_device_register failed\n",
132                        __func__);
133                 goto error_free_fw_priv;
134         }
135
136         retval = sysfs_create_bin_file(&class_dev->kobj, &firmware_attr_data);
137         if (retval) {
138                 printk(KERN_ERR "%s: sysfs_create_bin_file failed\n",
139                        __func__);
140                 goto error_unreg_class_dev;
141         }
142
143         retval = class_device_create_file(class_dev,
144                                           &class_device_attr_loading);
145         if (retval) {
146                 printk(KERN_ERR "%s: class_device_create_file failed\n",
147                        __func__);
148                 goto error_remove_data;
149         }
150
151         goto out;
152
153 error_remove_data:
154         sysfs_remove_bin_file(&class_dev->kobj, &firmware_attr_data);
155 error_unreg_class_dev:
156         class_device_unregister(class_dev);
157 error_free_fw_priv:
158         kfree(fw_priv);
159 out:
160         return retval;
161 }
162 static void fw_remove_class_device(struct class_device *class_dev)
163 {
164         struct firmware_priv *fw_priv = class_get_devdata(class_dev);
165
166         class_device_remove_file(class_dev, &class_device_attr_loading);
167         sysfs_remove_bin_file(&class_dev->kobj, &firmware_attr_data);
168         class_device_unregister(class_dev);
169 }
170
171 static struct class_device *class_dev;
172
173 static struct device my_device = {
174         .bus_id    = "my_dev0",
175 };
176
177 static int __init firmware_sample_init(void)
178 {
179         int error;
180
181         device_initialize(&my_device);
182         class_dev = kmalloc(sizeof(struct class_device), GFP_KERNEL);
183         if (!class_dev)
184                 return -ENOMEM;
185
186         error = fw_setup_class_device(class_dev, "my_firmware_image",
187                                       &my_device);
188         if (error) {
189                 kfree(class_dev);
190                 return error;
191         }
192         return 0;
193
194 }
195 static void __exit firmware_sample_exit(void)
196 {
197         struct firmware_priv *fw_priv = class_get_devdata(class_dev);
198         fw_remove_class_device(class_dev);
199         kfree(fw_priv);
200         kfree(class_dev);
201 }
202
203 module_init(firmware_sample_init);
204 module_exit(firmware_sample_exit);