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
to_class_dev(struct kobject * obj)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
to_class_dev_attr(struct attribute * _attr)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
firmware_loading_show(struct class_device * class_dev,char * buf)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
firmware_loading_store(struct class_device * class_dev,const char * buf,size_t count)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
firmware_data_read(struct kobject * kobj,struct bin_attribute * bin_attr,char * buffer,loff_t offset,size_t count)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 }
firmware_data_write(struct kobject * kobj,struct bin_attribute * bin_attr,char * buffer,loff_t offset,size_t count)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 };
fw_setup_class_device(struct class_device * class_dev,const char * fw_name,struct device * device)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 }
fw_remove_class_device(struct class_device * class_dev)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
firmware_sample_init(void)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 }
firmware_sample_exit(void)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);
205