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 */ 33 struct 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. */ 47 extern int hwrng_register(struct hwrng *rng); 48 /** Unregister a Hardware Random Number Generator driver. */ 49 extern void hwrng_unregister(struct hwrng *rng); 50 51 #endif /* LINUX_HWRANDOM_H_ */ 52