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 #ifdef __KERNEL__ 15 16 #include <linux/types.h> 17 #include <linux/list.h> 18 19 /** 20 * struct hwrng - Hardware Random Number Generator driver 21 * @name: Unique RNG name. 22 * @init: Initialization callback (can be NULL). 23 * @cleanup: Cleanup callback (can be NULL). 24 * @data_present: Callback to determine if data is available 25 * on the RNG. If NULL, it is assumed that 26 * there is always data available. 27 * @data_read: Read data from the RNG device. 28 * Returns the number of lower random bytes in "data". 29 * Must not be NULL. 30 * @priv: Private data, for use by the RNG driver. 31 */ 32 struct hwrng { 33 const char *name; 34 int (*init)(struct hwrng *rng); 35 void (*cleanup)(struct hwrng *rng); 36 int (*data_present)(struct hwrng *rng, int wait); 37 int (*data_read)(struct hwrng *rng, u32 *data); 38 unsigned long priv; 39 40 /* internal. */ 41 struct list_head list; 42 }; 43 44 /** Register a new Hardware Random Number Generator driver. */ 45 extern int hwrng_register(struct hwrng *rng); 46 /** Unregister a Hardware Random Number Generator driver. */ 47 extern void hwrng_unregister(struct hwrng *rng); 48 49 #endif /* __KERNEL__ */ 50 #endif /* LINUX_HWRANDOM_H_ */ 51