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Diffstat (limited to 'Documentation/firmware_class/firmware_sample_driver.c')
-rw-r--r-- | Documentation/firmware_class/firmware_sample_driver.c | 126 |
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 new file mode 100644 index 00000000000..e1c56a7e658 --- /dev/null +++ b/Documentation/firmware_class/firmware_sample_driver.c @@ -0,0 +1,126 @@ +/* + * 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"); |