Commit 31f4233b authored by Nicolas Pitre's avatar Nicolas Pitre Committed by Thomas Gleixner

[MTD] User interface to Protection Registers

This is implemented using a ioctl to switch the MTD char device into
one of the different OTP "modes", at which point read/write/seek can
operate on the selected OTP area.  Also some extra ioctls to query
for size and lock protection segments or groups.  Some example user
space utilities are provided.
Signed-off-by: default avatarNicolas Pitre <nico@cam.org>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent f77814dd
/*
* $Id: mtdchar.c,v 1.66 2005/01/05 18:05:11 dwmw2 Exp $
* $Id: mtdchar.c,v 1.67 2005/02/08 17:45:51 nico Exp $
*
* Character-device access to raw MTD devices.
*
......@@ -59,6 +59,12 @@ static inline void mtdchar_devfs_exit(void)
#define mtdchar_devfs_exit() do { } while(0)
#endif
/* Well... let's abuse the unused bits in file->f_mode for those */
#define MTD_MODE_OTP_FACT 0x1000
#define MTD_MODE_OTP_USER 0x2000
#define MTD_MODE_MASK 0xf000
static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
{
struct mtd_info *mtd = file->private_data;
......@@ -105,6 +111,10 @@ static int mtd_open(struct inode *inode, struct file *file)
if ((file->f_mode & 2) && (minor & 1))
return -EACCES;
/* make sure the locally abused bits are initialy clear */
if (file->f_mode & MTD_MODE_MASK)
return -EWOULDBLOCK;
mtd = get_mtd_device(NULL, devnum);
if (!mtd)
......@@ -178,7 +188,16 @@ static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t
if (!kbuf)
return -ENOMEM;
ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
switch (file->f_mode & MTD_MODE_MASK) {
case MTD_MODE_OTP_FACT:
ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
break;
case MTD_MODE_OTP_USER:
ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
break;
default:
ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
}
/* Nand returns -EBADMSG on ecc errors, but it returns
* the data. For our userspace tools it is important
* to dump areas with ecc errors !
......@@ -196,6 +215,8 @@ static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t
count -= retlen;
buf += retlen;
if (retlen == 0)
count = 0;
}
else {
kfree(kbuf);
......@@ -245,7 +266,20 @@ static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count
return -EFAULT;
}
ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
switch (file->f_mode & MTD_MODE_MASK) {
case MTD_MODE_OTP_FACT:
ret = -EROFS;
break;
case MTD_MODE_OTP_USER:
if (!mtd->write_user_prot_reg) {
ret = -EOPNOTSUPP;
break;
}
ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
break;
default:
ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
}
if (!ret) {
*ppos += retlen;
total_retlen += retlen;
......@@ -518,6 +552,79 @@ static int mtd_ioctl(struct inode *inode, struct file *file,
break;
}
#ifdef CONFIG_MTD_OTP
case OTPSELECT:
{
int mode;
if (copy_from_user(&mode, argp, sizeof(int)))
return -EFAULT;
file->f_mode &= ~MTD_MODE_MASK;
switch (mode) {
case MTD_OTP_FACTORY:
if (!mtd->read_fact_prot_reg)
ret = -EOPNOTSUPP;
else
file->f_mode |= MTD_MODE_OTP_FACT;
break;
case MTD_OTP_USER:
if (!mtd->read_fact_prot_reg)
ret = -EOPNOTSUPP;
else
file->f_mode |= MTD_MODE_OTP_USER;
break;
default:
ret = -EINVAL;
case MTD_OTP_OFF:
break;
}
break;
}
case OTPGETREGIONCOUNT:
case OTPGETREGIONINFO:
{
struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = -EOPNOTSUPP;
switch (file->f_mode & MTD_MODE_MASK) {
case MTD_MODE_OTP_FACT:
if (mtd->get_fact_prot_info)
ret = mtd->get_fact_prot_info(mtd, buf, 4096);
break;
case MTD_MODE_OTP_USER:
if (mtd->get_user_prot_info)
ret = mtd->get_user_prot_info(mtd, buf, 4096);
break;
}
if (ret >= 0) {
if (cmd == OTPGETREGIONCOUNT) {
int nbr = ret / sizeof(struct otp_info);
ret = copy_to_user(argp, &nbr, sizeof(int));
} else
ret = copy_to_user(argp, buf, ret);
if (ret)
ret = -EFAULT;
}
kfree(buf);
break;
}
case OTPLOCK:
{
struct otp_info info;
if ((file->f_mode & MTD_MODE_MASK) != MTD_MODE_OTP_USER)
return -EINVAL;
if (copy_from_user(&info, argp, sizeof(info)))
return -EFAULT;
if (!mtd->lock_user_prot_reg)
return -EOPNOTSUPP;
ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
break;
}
#endif
default:
ret = -ENOTTY;
}
......
/*
* $Id: mtd-abi.h,v 1.8 2005/02/08 17:11:16 nico Exp $
* $Id: mtd-abi.h,v 1.9 2005/02/08 17:45:52 nico Exp $
*
* Portions of MTD ABI definition which are shared by kernel and user space
*/
......@@ -61,6 +61,11 @@ struct mtd_oob_buf {
#define MTD_NANDECC_AUTOPLACE 2 // Use the default placement scheme
#define MTD_NANDECC_PLACEONLY 3 // Use the given placement in the structure (Do not store ecc result on read)
/* OTP mode selection */
#define MTD_OTP_OFF 0
#define MTD_OTP_FACTORY 1
#define MTD_OTP_USER 2
struct mtd_info_user {
uint8_t type;
uint32_t flags;
......@@ -98,6 +103,10 @@ struct otp_info {
#define MEMGETOOBSEL _IOR('M', 10, struct nand_oobinfo)
#define MEMGETBADBLOCK _IOW('M', 11, loff_t)
#define MEMSETBADBLOCK _IOW('M', 12, loff_t)
#define OTPSELECT _IOR('M', 13, int)
#define OTPGETREGIONCOUNT _IOW('M', 14, int)
#define OTPGETREGIONINFO _IOW('M', 15, struct otp_info)
#define OTPLOCK _IOR('M', 16, struct otp_info)
struct nand_oobinfo {
uint32_t useecc;
......
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