root/samples/firmware_class/firmware_sample_driver.c

DEFINITIONS

1. sample_firmware_load
2. sample_probe_default
3. sample_probe_specific
4. sample_probe_async_cont
5. sample_probe_async
6. sample_init
7. sample_exit

/*
 * firmware_sample_driver.c -
 *
 * Copyright (c) 2003 Manuel Estrada Sainz
 *
 * Sample code on how to use request_firmware() from drivers.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/string.h>
#include <linux/firmware.h>

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;
        int retval;

        printk(KERN_INFO "firmware_sample_driver: "
                "a ghost device got inserted :)\n");

        retval = request_firmware(&fw_entry, "sample_driver_fw", &ghost_device);
        if (retval) {
                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)
{
        int retval;
        /* 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");

        retval = request_firmware(NULL, "sample_driver_fw", &ghost_device);
        if (retval) {
                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)
{
        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");