xref: /linux/include/linux/mtd/mtd.h (revision 42fda66387daa53538ae13a2c858396aaf037158)
1 /*
2  * $Id: mtd.h,v 1.61 2005/11/07 11:14:54 gleixner Exp $
3  *
4  * Copyright (C) 1999-2003 David Woodhouse <dwmw2@infradead.org> et al.
5  *
6  * Released under GPL
7  */
8 
9 #ifndef __MTD_MTD_H__
10 #define __MTD_MTD_H__
11 
12 #include <linux/types.h>
13 #include <linux/module.h>
14 #include <linux/uio.h>
15 #include <linux/notifier.h>
16 
17 #include <linux/mtd/compatmac.h>
18 #include <mtd/mtd-abi.h>
19 
20 #define MTD_CHAR_MAJOR 90
21 #define MTD_BLOCK_MAJOR 31
22 #define MAX_MTD_DEVICES 32
23 
24 #define MTD_ERASE_PENDING      	0x01
25 #define MTD_ERASING		0x02
26 #define MTD_ERASE_SUSPEND	0x04
27 #define MTD_ERASE_DONE          0x08
28 #define MTD_ERASE_FAILED        0x10
29 
30 /* If the erase fails, fail_addr might indicate exactly which block failed.  If
31    fail_addr = 0xffffffff, the failure was not at the device level or was not
32    specific to any particular block. */
33 struct erase_info {
34 	struct mtd_info *mtd;
35 	u_int32_t addr;
36 	u_int32_t len;
37 	u_int32_t fail_addr;
38 	u_long time;
39 	u_long retries;
40 	u_int dev;
41 	u_int cell;
42 	void (*callback) (struct erase_info *self);
43 	u_long priv;
44 	u_char state;
45 	struct erase_info *next;
46 };
47 
48 struct mtd_erase_region_info {
49 	u_int32_t offset;			/* At which this region starts, from the beginning of the MTD */
50 	u_int32_t erasesize;		/* For this region */
51 	u_int32_t numblocks;		/* Number of blocks of erasesize in this region */
52 	unsigned long *lockmap;		/* If keeping bitmap of locks */
53 };
54 
55 /*
56  * oob operation modes
57  *
58  * MTD_OOB_PLACE:	oob data are placed at the given offset
59  * MTD_OOB_AUTO:	oob data are automatically placed at the free areas
60  *			which are defined by the ecclayout
61  * MTD_OOB_RAW:		mode to read raw data+oob in one chunk. The oob data
62  *			is inserted into the data. Thats a raw image of the
63  *			flash contents.
64  */
65 typedef enum {
66 	MTD_OOB_PLACE,
67 	MTD_OOB_AUTO,
68 	MTD_OOB_RAW,
69 } mtd_oob_mode_t;
70 
71 /**
72  * struct mtd_oob_ops - oob operation operands
73  * @mode:	operation mode
74  *
75  * @len:	number of data bytes to write/read
76  *
77  * @retlen:	number of data bytes written/read
78  *
79  * @ooblen:	number of oob bytes to write/read
80  * @oobretlen:	number of oob bytes written/read
81  * @ooboffs:	offset of oob data in the oob area (only relevant when
82  *		mode = MTD_OOB_PLACE)
83  * @datbuf:	data buffer - if NULL only oob data are read/written
84  * @oobbuf:	oob data buffer
85  *
86  * Note, it is allowed to read more then one OOB area at one go, but not write.
87  * The interface assumes that the OOB write requests program only one page's
88  * OOB area.
89  */
90 struct mtd_oob_ops {
91 	mtd_oob_mode_t	mode;
92 	size_t		len;
93 	size_t		retlen;
94 	size_t		ooblen;
95 	size_t		oobretlen;
96 	uint32_t	ooboffs;
97 	uint8_t		*datbuf;
98 	uint8_t		*oobbuf;
99 };
100 
101 struct mtd_info {
102 	u_char type;
103 	u_int32_t flags;
104 	u_int32_t size;	 // Total size of the MTD
105 
106 	/* "Major" erase size for the device. Naïve users may take this
107 	 * to be the only erase size available, or may use the more detailed
108 	 * information below if they desire
109 	 */
110 	u_int32_t erasesize;
111 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
112 	 * though individual bits can be cleared), in case of NAND flash it is
113 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
114 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
115 	 * Any driver registering a struct mtd_info must ensure a writesize of
116 	 * 1 or larger.
117 	 */
118 	u_int32_t writesize;
119 
120 	u_int32_t oobsize;   // Amount of OOB data per block (e.g. 16)
121 	u_int32_t oobavail;  // Available OOB bytes per block
122 
123 	// Kernel-only stuff starts here.
124 	char *name;
125 	int index;
126 
127 	/* ecc layout structure pointer - read only ! */
128 	struct nand_ecclayout *ecclayout;
129 
130 	/* Data for variable erase regions. If numeraseregions is zero,
131 	 * it means that the whole device has erasesize as given above.
132 	 */
133 	int numeraseregions;
134 	struct mtd_erase_region_info *eraseregions;
135 
136 	/*
137 	 * Erase is an asynchronous operation.  Device drivers are supposed
138 	 * to call instr->callback() whenever the operation completes, even
139 	 * if it completes with a failure.
140 	 * Callers are supposed to pass a callback function and wait for it
141 	 * to be called before writing to the block.
142 	 */
143 	int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
144 
145 	/* This stuff for eXecute-In-Place */
146 	int (*point) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char **mtdbuf);
147 
148 	/* We probably shouldn't allow XIP if the unpoint isn't a NULL */
149 	void (*unpoint) (struct mtd_info *mtd, u_char * addr, loff_t from, size_t len);
150 
151 
152 	int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
153 	int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
154 
155 	int (*read_oob) (struct mtd_info *mtd, loff_t from,
156 			 struct mtd_oob_ops *ops);
157 	int (*write_oob) (struct mtd_info *mtd, loff_t to,
158 			 struct mtd_oob_ops *ops);
159 
160 	/*
161 	 * Methods to access the protection register area, present in some
162 	 * flash devices. The user data is one time programmable but the
163 	 * factory data is read only.
164 	 */
165 	int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
166 	int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
167 	int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
168 	int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
169 	int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
170 	int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
171 
172 	/* kvec-based read/write methods.
173 	   NB: The 'count' parameter is the number of _vectors_, each of
174 	   which contains an (ofs, len) tuple.
175 	*/
176 	int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
177 
178 	/* Sync */
179 	void (*sync) (struct mtd_info *mtd);
180 
181 	/* Chip-supported device locking */
182 	int (*lock) (struct mtd_info *mtd, loff_t ofs, size_t len);
183 	int (*unlock) (struct mtd_info *mtd, loff_t ofs, size_t len);
184 
185 	/* Power Management functions */
186 	int (*suspend) (struct mtd_info *mtd);
187 	void (*resume) (struct mtd_info *mtd);
188 
189 	/* Bad block management functions */
190 	int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
191 	int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
192 
193 	struct notifier_block reboot_notifier;  /* default mode before reboot */
194 
195 	/* ECC status information */
196 	struct mtd_ecc_stats ecc_stats;
197 	/* Subpage shift (NAND) */
198 	int subpage_sft;
199 
200 	void *priv;
201 
202 	struct module *owner;
203 	int usecount;
204 
205 	/* If the driver is something smart, like UBI, it may need to maintain
206 	 * its own reference counting. The below functions are only for driver.
207 	 * The driver may register its callbacks. These callbacks are not
208 	 * supposed to be called by MTD users */
209 	int (*get_device) (struct mtd_info *mtd);
210 	void (*put_device) (struct mtd_info *mtd);
211 };
212 
213 
214 	/* Kernel-side ioctl definitions */
215 
216 extern int add_mtd_device(struct mtd_info *mtd);
217 extern int del_mtd_device (struct mtd_info *mtd);
218 
219 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
220 extern struct mtd_info *get_mtd_device_nm(const char *name);
221 
222 extern void put_mtd_device(struct mtd_info *mtd);
223 
224 
225 struct mtd_notifier {
226 	void (*add)(struct mtd_info *mtd);
227 	void (*remove)(struct mtd_info *mtd);
228 	struct list_head list;
229 };
230 
231 
232 extern void register_mtd_user (struct mtd_notifier *new);
233 extern int unregister_mtd_user (struct mtd_notifier *old);
234 
235 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
236 		       unsigned long count, loff_t to, size_t *retlen);
237 
238 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
239 		      unsigned long count, loff_t from, size_t *retlen);
240 
241 #ifdef CONFIG_MTD_PARTITIONS
242 void mtd_erase_callback(struct erase_info *instr);
243 #else
244 static inline void mtd_erase_callback(struct erase_info *instr)
245 {
246 	if (instr->callback)
247 		instr->callback(instr);
248 }
249 #endif
250 
251 /*
252  * Debugging macro and defines
253  */
254 #define MTD_DEBUG_LEVEL0	(0)	/* Quiet   */
255 #define MTD_DEBUG_LEVEL1	(1)	/* Audible */
256 #define MTD_DEBUG_LEVEL2	(2)	/* Loud    */
257 #define MTD_DEBUG_LEVEL3	(3)	/* Noisy   */
258 
259 #ifdef CONFIG_MTD_DEBUG
260 #define DEBUG(n, args...)				\
261 	do {						\
262 		if (n <= CONFIG_MTD_DEBUG_VERBOSE)	\
263 			printk(KERN_INFO args);		\
264 	} while(0)
265 #else /* CONFIG_MTD_DEBUG */
266 #define DEBUG(n, args...) do { } while(0)
267 
268 #endif /* CONFIG_MTD_DEBUG */
269 
270 #endif /* __MTD_MTD_H__ */
271