2 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 #include <linux/types.h>
24 #include <linux/module.h>
25 #include <linux/uio.h>
26 #include <linux/notifier.h>
27 #include <linux/device.h>
29 #include <mtd/mtd-abi.h>
31 #include <asm/div64.h>
33 #define MTD_CHAR_MAJOR 90
34 #define MTD_BLOCK_MAJOR 31
36 #define MTD_ERASE_PENDING 0x01
37 #define MTD_ERASING 0x02
38 #define MTD_ERASE_SUSPEND 0x04
39 #define MTD_ERASE_DONE 0x08
40 #define MTD_ERASE_FAILED 0x10
42 #define MTD_FAIL_ADDR_UNKNOWN -1LL
44 /* If the erase fails, fail_addr might indicate exactly which block failed. If
45 fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level or was not
46 specific to any particular block. */
56 void (*callback) (struct erase_info *self);
59 struct erase_info *next;
62 struct mtd_erase_region_info {
63 uint64_t offset; /* At which this region starts, from the beginning of the MTD */
64 uint32_t erasesize; /* For this region */
65 uint32_t numblocks; /* Number of blocks of erasesize in this region */
66 unsigned long *lockmap; /* If keeping bitmap of locks */
72 * MTD_OOB_PLACE: oob data are placed at the given offset
73 * MTD_OOB_AUTO: oob data are automatically placed at the free areas
74 * which are defined by the ecclayout
75 * MTD_OOB_RAW: mode to read oob and data without doing ECC checking
84 * struct mtd_oob_ops - oob operation operands
85 * @mode: operation mode
87 * @len: number of data bytes to write/read
89 * @retlen: number of data bytes written/read
91 * @ooblen: number of oob bytes to write/read
92 * @oobretlen: number of oob bytes written/read
93 * @ooboffs: offset of oob data in the oob area (only relevant when
94 * mode = MTD_OOB_PLACE)
95 * @datbuf: data buffer - if NULL only oob data are read/written
96 * @oobbuf: oob data buffer
98 * Note, it is allowed to read more than one OOB area at one go, but not write.
99 * The interface assumes that the OOB write requests program only one page's
113 #define MTD_MAX_OOBFREE_ENTRIES_LARGE 32
114 #define MTD_MAX_ECCPOS_ENTRIES_LARGE 448
116 * Internal ECC layout control structure. For historical reasons, there is a
117 * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained
118 * for export to user-space via the ECCGETLAYOUT ioctl.
119 * nand_ecclayout should be expandable in the future simply by the above macros.
121 struct nand_ecclayout {
123 __u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE];
125 struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
131 uint64_t size; // Total size of the MTD
133 /* "Major" erase size for the device. Naïve users may take this
134 * to be the only erase size available, or may use the more detailed
135 * information below if they desire
138 /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
139 * though individual bits can be cleared), in case of NAND flash it is
140 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
141 * it is of ECC block size, etc. It is illegal to have writesize = 0.
142 * Any driver registering a struct mtd_info must ensure a writesize of
147 uint32_t oobsize; // Amount of OOB data per block (e.g. 16)
148 uint32_t oobavail; // Available OOB bytes per block
151 * If erasesize is a power of 2 then the shift is stored in
152 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
154 unsigned int erasesize_shift;
155 unsigned int writesize_shift;
156 /* Masks based on erasesize_shift and writesize_shift */
157 unsigned int erasesize_mask;
158 unsigned int writesize_mask;
160 // Kernel-only stuff starts here.
164 /* ecc layout structure pointer - read only ! */
165 struct nand_ecclayout *ecclayout;
167 /* Data for variable erase regions. If numeraseregions is zero,
168 * it means that the whole device has erasesize as given above.
171 struct mtd_erase_region_info *eraseregions;
174 * Erase is an asynchronous operation. Device drivers are supposed
175 * to call instr->callback() whenever the operation completes, even
176 * if it completes with a failure.
177 * Callers are supposed to pass a callback function and wait for it
178 * to be called before writing to the block.
180 int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
182 /* This stuff for eXecute-In-Place */
183 /* phys is optional and may be set to NULL */
184 int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
185 size_t *retlen, void **virt, resource_size_t *phys);
187 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
188 void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
190 /* Allow NOMMU mmap() to directly map the device (if not NULL)
191 * - return the address to which the offset maps
192 * - return -ENOSYS to indicate refusal to do the mapping
194 unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
196 unsigned long offset,
197 unsigned long flags);
199 /* Backing device capabilities for this device
200 * - provides mmap capabilities
202 struct backing_dev_info *backing_dev_info;
205 int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
206 int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
208 /* In blackbox flight recorder like scenarios we want to make successful
209 writes in interrupt context. panic_write() is only intended to be
210 called when its known the kernel is about to panic and we need the
211 write to succeed. Since the kernel is not going to be running for much
212 longer, this function can break locks and delay to ensure the write
213 succeeds (but not sleep). */
215 int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
217 int (*read_oob) (struct mtd_info *mtd, loff_t from,
218 struct mtd_oob_ops *ops);
219 int (*write_oob) (struct mtd_info *mtd, loff_t to,
220 struct mtd_oob_ops *ops);
223 * Methods to access the protection register area, present in some
224 * flash devices. The user data is one time programmable but the
225 * factory data is read only.
227 int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
228 int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
229 int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
230 int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
231 int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
232 int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
234 /* kvec-based read/write methods.
235 NB: The 'count' parameter is the number of _vectors_, each of
236 which contains an (ofs, len) tuple.
238 int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
241 void (*sync) (struct mtd_info *mtd);
243 /* Chip-supported device locking */
244 int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
245 int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
246 int (*is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
248 /* Power Management functions */
249 int (*suspend) (struct mtd_info *mtd);
250 void (*resume) (struct mtd_info *mtd);
252 /* Bad block management functions */
253 int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
254 int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
256 struct notifier_block reboot_notifier; /* default mode before reboot */
258 /* ECC status information */
259 struct mtd_ecc_stats ecc_stats;
260 /* Subpage shift (NAND) */
265 struct module *owner;
269 /* If the driver is something smart, like UBI, it may need to maintain
270 * its own reference counting. The below functions are only for driver.
271 * The driver may register its callbacks. These callbacks are not
272 * supposed to be called by MTD users */
273 int (*get_device) (struct mtd_info *mtd);
274 void (*put_device) (struct mtd_info *mtd);
277 static inline struct mtd_info *dev_to_mtd(struct device *dev)
279 return dev ? dev_get_drvdata(dev) : NULL;
282 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
284 if (mtd->erasesize_shift)
285 return sz >> mtd->erasesize_shift;
286 do_div(sz, mtd->erasesize);
290 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
292 if (mtd->erasesize_shift)
293 return sz & mtd->erasesize_mask;
294 return do_div(sz, mtd->erasesize);
297 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
299 if (mtd->writesize_shift)
300 return sz >> mtd->writesize_shift;
301 do_div(sz, mtd->writesize);
305 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
307 if (mtd->writesize_shift)
308 return sz & mtd->writesize_mask;
309 return do_div(sz, mtd->writesize);
312 /* Kernel-side ioctl definitions */
314 extern int add_mtd_device(struct mtd_info *mtd);
315 extern int del_mtd_device (struct mtd_info *mtd);
317 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
318 extern int __get_mtd_device(struct mtd_info *mtd);
319 extern void __put_mtd_device(struct mtd_info *mtd);
320 extern struct mtd_info *get_mtd_device_nm(const char *name);
321 extern void put_mtd_device(struct mtd_info *mtd);
324 struct mtd_notifier {
325 void (*add)(struct mtd_info *mtd);
326 void (*remove)(struct mtd_info *mtd);
327 struct list_head list;
331 extern void register_mtd_user (struct mtd_notifier *new);
332 extern int unregister_mtd_user (struct mtd_notifier *old);
334 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
335 unsigned long count, loff_t to, size_t *retlen);
337 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
338 unsigned long count, loff_t from, size_t *retlen);
340 #ifdef CONFIG_MTD_PARTITIONS
341 void mtd_erase_callback(struct erase_info *instr);
343 static inline void mtd_erase_callback(struct erase_info *instr)
346 instr->callback(instr);
351 * Debugging macro and defines
353 #define MTD_DEBUG_LEVEL0 (0) /* Quiet */
354 #define MTD_DEBUG_LEVEL1 (1) /* Audible */
355 #define MTD_DEBUG_LEVEL2 (2) /* Loud */
356 #define MTD_DEBUG_LEVEL3 (3) /* Noisy */
358 #ifdef CONFIG_MTD_DEBUG
359 #define DEBUG(n, args...) \
361 if (n <= CONFIG_MTD_DEBUG_VERBOSE) \
362 printk(KERN_INFO args); \
364 #else /* CONFIG_MTD_DEBUG */
365 #define DEBUG(n, args...) \
368 printk(KERN_INFO args); \
371 #endif /* CONFIG_MTD_DEBUG */
373 #endif /* __MTD_MTD_H__ */