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