74 static int hwrng_init(struct hwrng *rng);
77 static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
85 static void add_early_randomness(struct hwrng *rng)  in add_early_randomness()  argument
91 	bytes_read = rng_get_data(rng, rng_buffer, size, 0);  in add_early_randomness()
99 	struct hwrng *rng = container_of(kref, struct hwrng, ref);  in cleanup_rng()  local
101 	if (rng->cleanup)  in cleanup_rng()
102 		rng->cleanup(rng);  in cleanup_rng()
104 	complete(&rng->cleanup_done);  in cleanup_rng()
107 static int set_current_rng(struct hwrng *rng)  in set_current_rng()  argument
113 	err = hwrng_init(rng);  in set_current_rng()
118 	current_rng = rng;  in set_current_rng()
137 	struct hwrng *rng;  in get_current_rng()  local
142 	rng = current_rng;  in get_current_rng()
143 	if (rng)  in get_current_rng()
144 		kref_get(&rng->ref);  in get_current_rng()
147 	return rng;  in get_current_rng()
150 static void put_rng(struct hwrng *rng)  in put_rng()  argument
157 	if (rng)  in put_rng()
158 		kref_put(&rng->ref, cleanup_rng);  in put_rng()
162 static int hwrng_init(struct hwrng *rng)  in hwrng_init()  argument
164 	if (kref_get_unless_zero(&rng->ref))  in hwrng_init()
167 	if (rng->init) {  in hwrng_init()
170 		ret =  rng->init(rng);  in hwrng_init()
175 	kref_init(&rng->ref);  in hwrng_init()
176 	reinit_completion(&rng->cleanup_done);  in hwrng_init()
179 	add_early_randomness(rng);  in hwrng_init()
181 	current_quality = rng->quality ? : default_quality;  in hwrng_init()
203 static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,  in rng_get_data()  argument
208 	if (rng->read)  in rng_get_data()
209 		return rng->read(rng, (void *)buffer, size, wait);  in rng_get_data()
211 	if (rng->data_present)  in rng_get_data()
212 		present = rng->data_present(rng, wait);  in rng_get_data()
217 		return rng->data_read(rng, (u32 *)buffer);  in rng_get_data()
228 	struct hwrng *rng;  in rng_dev_read()  local
231 		rng = get_current_rng();  in rng_dev_read()
232 		if (IS_ERR(rng)) {  in rng_dev_read()
233 			err = PTR_ERR(rng);  in rng_dev_read()
236 		if (!rng) {  in rng_dev_read()
246 			bytes_read = rng_get_data(rng, rng_buffer,  in rng_dev_read()
279 		put_rng(rng);  in rng_dev_read()
295 	put_rng(rng);  in rng_dev_read()
323 	struct hwrng *rng;  in hwrng_attr_current_store()  local
329 	list_for_each_entry(rng, &rng_list, list) {  in hwrng_attr_current_store()
330 		if (sysfs_streq(rng->name, buf)) {  in hwrng_attr_current_store()
332 			if (rng != current_rng)  in hwrng_attr_current_store()
333 				err = set_current_rng(rng);  in hwrng_attr_current_store()
347 	struct hwrng *rng;  in hwrng_attr_current_show()  local
349 	rng = get_current_rng();  in hwrng_attr_current_show()
350 	if (IS_ERR(rng))  in hwrng_attr_current_show()
351 		return PTR_ERR(rng);  in hwrng_attr_current_show()
353 	ret = snprintf(buf, PAGE_SIZE, "%s\n", rng ? rng->name : "none");  in hwrng_attr_current_show()
354 	put_rng(rng);  in hwrng_attr_current_show()
364 	struct hwrng *rng;  in hwrng_attr_available_show()  local
370 	list_for_each_entry(rng, &rng_list, list) {  in hwrng_attr_available_show()
371 		strlcat(buf, rng->name, PAGE_SIZE);  in hwrng_attr_available_show()
410 		struct hwrng *rng;  in hwrng_fillfn()  local
412 		rng = get_current_rng();  in hwrng_fillfn()
413 		if (IS_ERR(rng) || !rng)  in hwrng_fillfn()
416 		rc = rng_get_data(rng, rng_fillbuf,  in hwrng_fillfn()
419 		put_rng(rng);  in hwrng_fillfn()
442 int hwrng_register(struct hwrng *rng)  in hwrng_register()  argument
447 	if (rng->name == NULL ||  in hwrng_register()
448 	    (rng->data_read == NULL && rng->read == NULL))  in hwrng_register()
471 		if (strcmp(tmp->name, rng->name) == 0)  in hwrng_register()
475 	init_completion(&rng->cleanup_done);  in hwrng_register()
476 	complete(&rng->cleanup_done);  in hwrng_register()
481 		err = set_current_rng(rng);  in hwrng_register()
485 	list_add_tail(&rng->list, &rng_list);  in hwrng_register()
487 	if (old_rng && !rng->init) {  in hwrng_register()
495 		add_early_randomness(rng);  in hwrng_register()
505 void hwrng_unregister(struct hwrng *rng)  in hwrng_unregister()  argument
509 	list_del(&rng->list);  in hwrng_unregister()
510 	if (current_rng == rng) {  in hwrng_unregister()
528 	wait_for_completion(&rng->cleanup_done);  in hwrng_unregister()
547 int devm_hwrng_register(struct device *dev, struct hwrng *rng)  in devm_hwrng_register()  argument
556 	error = hwrng_register(rng);  in devm_hwrng_register()
562 	*ptr = rng;  in devm_hwrng_register()
568 void devm_hwrng_unregister(struct device *dev, struct hwrng *rng)  in devm_hwrng_unregister()  argument
570 	devres_release(dev, devm_hwrng_release, devm_hwrng_match, rng);  in devm_hwrng_unregister()