tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
16#include "linux/firmware.h"
17
18static struct device ghost_device = {
19 .bus_id = "ghost0",
20};
21
22
23static void sample_firmware_load(char *firmware, int size)
24{
25 u8 buf[size+1];
26 memcpy(buf, firmware, size);
27 buf[size] = '\0';
28 printk(KERN_INFO "firmware_sample_driver: firmware: %s\n", buf);
29}
30
31static void sample_probe_default(void)
32{
33 /* uses the default method to get the firmware */
34 const struct firmware *fw_entry;
35 printk(KERN_INFO "firmware_sample_driver: a ghost device got inserted :)\n");
36
37 if(request_firmware(&fw_entry, "sample_driver_fw", &ghost_device)!=0)
38 {
39 printk(KERN_ERR
40 "firmware_sample_driver: Firmware not available\n");
41 return;
42 }
43
44 sample_firmware_load(fw_entry->data, fw_entry->size);
45
46 release_firmware(fw_entry);
47
48 /* finish setting up the device */
49}
50static void sample_probe_specific(void)
51{
52 /* Uses some specific hotplug support to get the firmware from
53 * userspace directly into the hardware, or via some sysfs file */
54
55 /* NOTE: This currently doesn't work */
56
57 printk(KERN_INFO "firmware_sample_driver: a ghost device got inserted :)\n");
58
59 if(request_firmware(NULL, "sample_driver_fw", &ghost_device)!=0)
60 {
61 printk(KERN_ERR
62 "firmware_sample_driver: Firmware load failed\n");
63 return;
64 }
65
66 /* request_firmware blocks until userspace finished, so at
67 * this point the firmware should be already in the device */
68
69 /* finish setting up the device */
70}
71static void sample_probe_async_cont(const struct firmware *fw, void *context)
72{
73 if(!fw){
74 printk(KERN_ERR
75 "firmware_sample_driver: firmware load failed\n");
76 return;
77 }
78
79 printk(KERN_INFO "firmware_sample_driver: device pointer \"%s\"\n",
80 (char *)context);
81 sample_firmware_load(fw->data, fw->size);
82}
83static void sample_probe_async(void)
84{
85 /* Let's say that I can't sleep */
86 int error;
87 error = request_firmware_nowait (THIS_MODULE, FW_ACTION_NOHOTPLUG,
88 "sample_driver_fw", &ghost_device,
89 "my device pointer",
90 sample_probe_async_cont);
91 if(error){
92 printk(KERN_ERR
93 "firmware_sample_driver:"
94 " request_firmware_nowait failed\n");
95 }
96}
97
98static int sample_init(void)
99{
100 device_initialize(&ghost_device);
101 /* since there is no real hardware insertion I just call the
102 * sample probe functions here */
103 sample_probe_specific();
104 sample_probe_default();
105 sample_probe_async();
106 return 0;
107}
108static void __exit sample_exit(void)
109{
110}
111
112module_init (sample_init);
113module_exit (sample_exit);
114
115MODULE_LICENSE("GPL");