1 /*
2 * firmware_sample_driver.c -
3 *
4 * Copyright (c) 2003 Manuel Estrada Sainz <ranty@debian.org>
5 *
6 * Sample code on how to use request_firmware() from drivers.
7 *
8 * Note that register_firmware() is currently useless.
9 *
10 */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/string.h>
16
17 #include "linux/firmware.h"
18
19 #define WE_CAN_NEED_FIRMWARE_BEFORE_USERSPACE_IS_AVAILABLE
20 #ifdef WE_CAN_NEED_FIRMWARE_BEFORE_USERSPACE_IS_AVAILABLE
21 char __init inkernel_firmware[] = "let's say that this is firmware\n";
22 #endif
23
24 static char ghost_device[] = "ghost0";
25
sample_firmware_load(char * firmware,int size)26 static void sample_firmware_load(char *firmware, int size)
27 {
28 u8 buf[size+1];
29 memcpy(buf, firmware, size);
30 buf[size] = '\0';
31 printk("firmware_sample_driver: firmware: %s\n", buf);
32 }
33
sample_probe_default(void)34 static void sample_probe_default(void)
35 {
36 /* uses the default method to get the firmware */
37 const struct firmware *fw_entry;
38 printk("firmware_sample_driver: a ghost device got inserted :)\n");
39
40 if(request_firmware(&fw_entry, "sample_driver_fw", ghost_device)!=0)
41 {
42 printk(KERN_ERR
43 "firmware_sample_driver: Firmware not available\n");
44 return;
45 }
46
47 sample_firmware_load(fw_entry->data, fw_entry->size);
48
49 release_firmware(fw_entry);
50
51 /* finish setting up the device */
52 }
sample_probe_specific(void)53 static void sample_probe_specific(void)
54 {
55 /* Uses some specific hotplug support to get the firmware from
56 * userspace directly into the hardware, or via some sysfs file */
57
58 /* NOTE: This currently doesn't work */
59
60 printk("firmware_sample_driver: a ghost device got inserted :)\n");
61
62 if(request_firmware(NULL, "sample_driver_fw", ghost_device)!=0)
63 {
64 printk(KERN_ERR
65 "firmware_sample_driver: Firmware load failed\n");
66 return;
67 }
68
69 /* request_firmware blocks until userspace finished, so at
70 * this point the firmware should be already in the device */
71
72 /* finish setting up the device */
73 }
sample_probe_async_cont(const struct firmware * fw,void * context)74 static void sample_probe_async_cont(const struct firmware *fw, void *context)
75 {
76 if(!fw){
77 printk(KERN_ERR
78 "firmware_sample_driver: firmware load failed\n");
79 return;
80 }
81
82 printk("firmware_sample_driver: device pointer \"%s\"\n",
83 (char *)context);
84 sample_firmware_load(fw->data, fw->size);
85 }
sample_probe_async(void)86 static void sample_probe_async(void)
87 {
88 /* Let's say that I can't sleep */
89 int error;
90 error = request_firmware_nowait (THIS_MODULE,
91 "sample_driver_fw", ghost_device,
92 "my device pointer",
93 sample_probe_async_cont);
94 if(error){
95 printk(KERN_ERR
96 "firmware_sample_driver:"
97 " request_firmware_nowait failed\n");
98 }
99 }
100
sample_init(void)101 static int sample_init(void)
102 {
103 #ifdef WE_CAN_NEED_FIRMWARE_BEFORE_USERSPACE_IS_AVAILABLE
104 register_firmware("sample_driver_fw", inkernel_firmware,
105 sizeof(inkernel_firmware));
106 #endif
107 /* since there is no real hardware insertion I just call the
108 * sample probe functions here */
109 sample_probe_specific();
110 sample_probe_default();
111 sample_probe_async();
112 return 0;
113 }
sample_exit(void)114 static void __exit sample_exit(void)
115 {
116 }
117
118 module_init (sample_init);
119 module_exit (sample_exit);
120
121 MODULE_LICENSE("GPL");
122