Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/juhl/trivial
[linux-2.6.git] / samples / firmware_class / firmware_sample_driver.c
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
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
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
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
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
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
103 static int 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
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");