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-rw-r--r--Documentation/firmware_class/firmware_sample_driver.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/Documentation/firmware_class/firmware_sample_driver.c b/Documentation/firmware_class/firmware_sample_driver.c
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+++ b/Documentation/firmware_class/firmware_sample_driver.c
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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/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 = {
+ .name = "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("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("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("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("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,
+ "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");