acrn-kernel/Documentation/firmware_class/firmware_sample_firmware_cl...

206 lines
5.1 KiB
C

/*
* firmware_sample_firmware_class.c -
*
* Copyright (c) 2003 Manuel Estrada Sainz <ranty@debian.org>
*
* NOTE: This is just a probe of concept, if you think that your driver would
* be well served by this mechanism please contact me first.
*
* DON'T USE THIS CODE AS IS
*
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/firmware.h>
MODULE_AUTHOR("Manuel Estrada Sainz <ranty@debian.org>");
MODULE_DESCRIPTION("Hackish sample for using firmware class directly");
MODULE_LICENSE("GPL");
static inline struct class_device *to_class_dev(struct kobject *obj)
{
return container_of(obj,struct class_device,kobj);
}
static inline
struct class_device_attribute *to_class_dev_attr(struct attribute *_attr)
{
return container_of(_attr,struct class_device_attribute,attr);
}
int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr);
int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr);
struct firmware_priv {
char fw_id[FIRMWARE_NAME_MAX];
s32 loading:2;
u32 abort:1;
};
extern struct class firmware_class;
static ssize_t firmware_loading_show(struct class_device *class_dev, char *buf)
{
struct firmware_priv *fw_priv = class_get_devdata(class_dev);
return sprintf(buf, "%d\n", fw_priv->loading);
}
static ssize_t firmware_loading_store(struct class_device *class_dev,
const char *buf, size_t count)
{
struct firmware_priv *fw_priv = class_get_devdata(class_dev);
int prev_loading = fw_priv->loading;
fw_priv->loading = simple_strtol(buf, NULL, 10);
switch(fw_priv->loading){
case -1:
/* abort load an panic */
break;
case 1:
/* setup load */
break;
case 0:
if(prev_loading==1){
/* finish load and get the device back to working
* state */
}
break;
}
return count;
}
static CLASS_DEVICE_ATTR(loading, 0644,
firmware_loading_show, firmware_loading_store);
static ssize_t firmware_data_read(struct kobject *kobj,
char *buffer, loff_t offset, size_t count)
{
struct class_device *class_dev = to_class_dev(kobj);
struct firmware_priv *fw_priv = class_get_devdata(class_dev);
/* read from the devices firmware memory */
return count;
}
static ssize_t firmware_data_write(struct kobject *kobj,
char *buffer, loff_t offset, size_t count)
{
struct class_device *class_dev = to_class_dev(kobj);
struct firmware_priv *fw_priv = class_get_devdata(class_dev);
/* write to the devices firmware memory */
return count;
}
static struct bin_attribute firmware_attr_data = {
.attr = {.name = "data", .mode = 0644},
.size = 0,
.read = firmware_data_read,
.write = firmware_data_write,
};
static int fw_setup_class_device(struct class_device *class_dev,
const char *fw_name,
struct device *device)
{
int retval = 0;
struct firmware_priv *fw_priv = kmalloc(sizeof(struct firmware_priv),
GFP_KERNEL);
if(!fw_priv){
retval = -ENOMEM;
goto out;
}
memset(fw_priv, 0, sizeof(*fw_priv));
memset(class_dev, 0, sizeof(*class_dev));
strncpy(fw_priv->fw_id, fw_name, FIRMWARE_NAME_MAX);
fw_priv->fw_id[FIRMWARE_NAME_MAX-1] = '\0';
strncpy(class_dev->class_id, device->bus_id, BUS_ID_SIZE);
class_dev->class_id[BUS_ID_SIZE-1] = '\0';
class_dev->dev = device;
class_dev->class = &firmware_class,
class_set_devdata(class_dev, fw_priv);
retval = class_device_register(class_dev);
if (retval){
printk(KERN_ERR "%s: class_device_register failed\n",
__FUNCTION__);
goto error_free_fw_priv;
}
retval = sysfs_create_bin_file(&class_dev->kobj, &firmware_attr_data);
if (retval){
printk(KERN_ERR "%s: sysfs_create_bin_file failed\n",
__FUNCTION__);
goto error_unreg_class_dev;
}
retval = class_device_create_file(class_dev,
&class_device_attr_loading);
if (retval){
printk(KERN_ERR "%s: class_device_create_file failed\n",
__FUNCTION__);
goto error_remove_data;
}
goto out;
error_remove_data:
sysfs_remove_bin_file(&class_dev->kobj, &firmware_attr_data);
error_unreg_class_dev:
class_device_unregister(class_dev);
error_free_fw_priv:
kfree(fw_priv);
out:
return retval;
}
static void fw_remove_class_device(struct class_device *class_dev)
{
struct firmware_priv *fw_priv = class_get_devdata(class_dev);
class_device_remove_file(class_dev, &class_device_attr_loading);
sysfs_remove_bin_file(&class_dev->kobj, &firmware_attr_data);
class_device_unregister(class_dev);
}
static struct class_device *class_dev;
static struct device my_device = {
.bus_id = "my_dev0",
};
static int __init firmware_sample_init(void)
{
int error;
device_initialize(&my_device);
class_dev = kmalloc(sizeof(struct class_device), GFP_KERNEL);
if(!class_dev)
return -ENOMEM;
error = fw_setup_class_device(class_dev, "my_firmware_image",
&my_device);
if(error){
kfree(class_dev);
return error;
}
return 0;
}
static void __exit firmware_sample_exit(void)
{
struct firmware_priv *fw_priv = class_get_devdata(class_dev);
fw_remove_class_device(class_dev);
kfree(fw_priv);
kfree(class_dev);
}
module_init(firmware_sample_init);
module_exit(firmware_sample_exit);