diff options
Diffstat (limited to 'drivers/macintosh/nvram.c')
-rw-r--r-- | drivers/macintosh/nvram.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/macintosh/nvram.c b/drivers/macintosh/nvram.c new file mode 100644 index 00000000000..30791875fc9 --- /dev/null +++ b/drivers/macintosh/nvram.c @@ -0,0 +1,131 @@ +/* + * /dev/nvram driver for Power Macintosh. + */ + +#define NVRAM_VERSION "1.0" + +#include <linux/module.h> + +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/fcntl.h> +#include <linux/nvram.h> +#include <linux/init.h> +#include <linux/smp_lock.h> +#include <asm/uaccess.h> +#include <asm/nvram.h> + +#define NVRAM_SIZE 8192 + +static loff_t nvram_llseek(struct file *file, loff_t offset, int origin) +{ + lock_kernel(); + switch (origin) { + case 1: + offset += file->f_pos; + break; + case 2: + offset += NVRAM_SIZE; + break; + } + if (offset < 0) { + unlock_kernel(); + return -EINVAL; + } + file->f_pos = offset; + unlock_kernel(); + return file->f_pos; +} + +static ssize_t read_nvram(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned int i; + char __user *p = buf; + + if (!access_ok(VERIFY_WRITE, buf, count)) + return -EFAULT; + if (*ppos >= NVRAM_SIZE) + return 0; + for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) + if (__put_user(nvram_read_byte(i), p)) + return -EFAULT; + *ppos = i; + return p - buf; +} + +static ssize_t write_nvram(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned int i; + const char __user *p = buf; + char c; + + if (!access_ok(VERIFY_READ, buf, count)) + return -EFAULT; + if (*ppos >= NVRAM_SIZE) + return 0; + for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) { + if (__get_user(c, p)) + return -EFAULT; + nvram_write_byte(c, i); + } + *ppos = i; + return p - buf; +} + +static int nvram_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + switch(cmd) { + case PMAC_NVRAM_GET_OFFSET: + { + int part, offset; + if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0) + return -EFAULT; + if (part < pmac_nvram_OF || part > pmac_nvram_NR) + return -EINVAL; + offset = pmac_get_partition(part); + if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0) + return -EFAULT; + break; + } + + default: + return -EINVAL; + } + + return 0; +} + +struct file_operations nvram_fops = { + .owner = THIS_MODULE, + .llseek = nvram_llseek, + .read = read_nvram, + .write = write_nvram, + .ioctl = nvram_ioctl, +}; + +static struct miscdevice nvram_dev = { + NVRAM_MINOR, + "nvram", + &nvram_fops +}; + +int __init nvram_init(void) +{ + printk(KERN_INFO "Macintosh non-volatile memory driver v%s\n", + NVRAM_VERSION); + return misc_register(&nvram_dev); +} + +void __exit nvram_cleanup(void) +{ + misc_deregister( &nvram_dev ); +} + +module_init(nvram_init); +module_exit(nvram_cleanup); +MODULE_LICENSE("GPL"); |