hw_random.h revision 988acec9ee9d8b38ca0d1187d904cb53588e8c64 
1/*
2	Hardware Random Number Generator
3
4	Please read Documentation/hw_random.txt for details on use.
5
6	----------------------------------------------------------
7	This software may be used and distributed according to the terms
8        of the GNU General Public License, incorporated herein by reference.
9
10 */
11
12#ifndef LINUX_HWRANDOM_H_
13#define LINUX_HWRANDOM_H_
14
15#include <linux/types.h>
16#include <linux/list.h>
17
18/**
19 * struct hwrng - Hardware Random Number Generator driver
20 * @name:		Unique RNG name.
21 * @init:		Initialization callback (can be NULL).
22 * @cleanup:		Cleanup callback (can be NULL).
23 * @data_present:	Callback to determine if data is available
24 *			on the RNG. If NULL, it is assumed that
25 *			there is always data available.  *OBSOLETE*
26 * @data_read:		Read data from the RNG device.
27 *			Returns the number of lower random bytes in "data".
28 *			Must not be NULL.    *OBSOLETE*
29 * @read:		New API. drivers can fill up to max bytes of data
30 *			into the buffer. The buffer is aligned for any type.
31 * @priv:		Private data, for use by the RNG driver.
32 */
33struct hwrng {
34	const char *name;
35	int (*init)(struct hwrng *rng);
36	void (*cleanup)(struct hwrng *rng);
37	int (*data_present)(struct hwrng *rng, int wait);
38	int (*data_read)(struct hwrng *rng, u32 *data);
39	int (*read)(struct hwrng *rng, void *data, size_t max, bool wait);
40	unsigned long priv;
41
42	/* internal. */
43	struct list_head list;
44};
45
46/** Register a new Hardware Random Number Generator driver. */
47extern int hwrng_register(struct hwrng *rng);
48/** Unregister a Hardware Random Number Generator driver. */
49extern void hwrng_unregister(struct hwrng *rng);
50
51#endif /* LINUX_HWRANDOM_H_ */
52