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/*
* firmware_sample_driver.c -
*
* Copyright (c) 2003 Manuel Estrada Sainz <ranty@debian.org>
*
* Sample code on how to use request_firmware() from drivers.
*
* Note that register_firmware() is currently useless.
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/string.h>
#include "linux/firmware.h"
#define WE_CAN_NEED_FIRMWARE_BEFORE_USERSPACE_IS_AVAILABLE
#ifdef WE_CAN_NEED_FIRMWARE_BEFORE_USERSPACE_IS_AVAILABLE
char __init inkernel_firmware[] = "let's say that this is firmware\n";
#endif
static struct device ghost_device = {
.bus_id = "ghost0",
};
static void sample_firmware_load(char *firmware, int size)
{
u8 buf[size+1];
memcpy(buf, firmware, size);
buf[size] = '\0';
printk(KERN_INFO "firmware_sample_driver: firmware: %s\n", buf);
}
static void sample_probe_default(void)
{
/* uses the default method to get the firmware */
const struct firmware *fw_entry;
printk(KERN_INFO "firmware_sample_driver: a ghost device got inserted :)\n");
if(request_firmware(&fw_entry, "sample_driver_fw", &ghost_device)!=0)
{
printk(KERN_ERR
"firmware_sample_driver: Firmware not available\n");
return;
}
sample_firmware_load(fw_entry->data, fw_entry->size);
release_firmware(fw_entry);
/* finish setting up the device */
}
static void sample_probe_specific(void)
{
/* Uses some specific hotplug support to get the firmware from
* userspace directly into the hardware, or via some sysfs file */
/* NOTE: This currently doesn't work */
printk(KERN_INFO "firmware_sample_driver: a ghost device got inserted :)\n");
if(request_firmware(NULL, "sample_driver_fw", &ghost_device)!=0)
{
printk(KERN_ERR
"firmware_sample_driver: Firmware load failed\n");
return;
}
/* request_firmware blocks until userspace finished, so at
* this point the firmware should be already in the device */
/* finish setting up the device */
}
static void sample_probe_async_cont(const struct firmware *fw, void *context)
{
if(!fw){
printk(KERN_ERR
"firmware_sample_driver: firmware load failed\n");
return;
}
printk(KERN_INFO "firmware_sample_driver: device pointer \"%s\"\n",
(char *)context);
sample_firmware_load(fw->data, fw->size);
}
static void sample_probe_async(void)
{
/* Let's say that I can't sleep */
int error;
error = request_firmware_nowait (THIS_MODULE, FW_ACTION_NOHOTPLUG,
"sample_driver_fw", &ghost_device,
"my device pointer",
sample_probe_async_cont);
if(error){
printk(KERN_ERR
"firmware_sample_driver:"
" request_firmware_nowait failed\n");
}
}
static int sample_init(void)
{
#ifdef WE_CAN_NEED_FIRMWARE_BEFORE_USERSPACE_IS_AVAILABLE
register_firmware("sample_driver_fw", inkernel_firmware,
sizeof(inkernel_firmware));
#endif
device_initialize(&ghost_device);
/* since there is no real hardware insertion I just call the
* sample probe functions here */
sample_probe_specific();
sample_probe_default();
sample_probe_async();
return 0;
}
static void __exit sample_exit(void)
{
}
module_init (sample_init);
module_exit (sample_exit);
MODULE_LICENSE("GPL");
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