53 static int hwrng_init(struct hwrng *rng);
56 static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
64 static void add_early_randomness(struct hwrng *rng)  in add_early_randomness()  argument
70 	bytes_read = rng_get_data(rng, rng_buffer, size, 0);  in add_early_randomness()
78 	struct hwrng *rng = container_of(kref, struct hwrng, ref);  in cleanup_rng()  local
80 	if (rng->cleanup)  in cleanup_rng()
81 		rng->cleanup(rng);  in cleanup_rng()
83 	complete(&rng->cleanup_done);  in cleanup_rng()
86 static int set_current_rng(struct hwrng *rng)  in set_current_rng()  argument
92 	err = hwrng_init(rng);  in set_current_rng()
97 	current_rng = rng;  in set_current_rng()
116 	struct hwrng *rng;  in get_current_rng()  local
121 	rng = current_rng;  in get_current_rng()
122 	if (rng)  in get_current_rng()
123 		kref_get(&rng->ref);  in get_current_rng()
126 	return rng;  in get_current_rng()
129 static void put_rng(struct hwrng *rng)  in put_rng()  argument
136 	if (rng)  in put_rng()
137 		kref_put(&rng->ref, cleanup_rng);  in put_rng()
141 static int hwrng_init(struct hwrng *rng)  in hwrng_init()  argument
143 	if (kref_get_unless_zero(&rng->ref))  in hwrng_init()
146 	if (rng->init) {  in hwrng_init()
149 		ret =  rng->init(rng);  in hwrng_init()
154 	kref_init(&rng->ref);  in hwrng_init()
155 	reinit_completion(&rng->cleanup_done);  in hwrng_init()
158 	add_early_randomness(rng);  in hwrng_init()
160 	current_quality = rng->quality ? : default_quality;  in hwrng_init()
182 static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,  in rng_get_data()  argument
187 	if (rng->read)  in rng_get_data()
188 		return rng->read(rng, (void *)buffer, size, wait);  in rng_get_data()
190 	if (rng->data_present)  in rng_get_data()
191 		present = rng->data_present(rng, wait);  in rng_get_data()
196 		return rng->data_read(rng, (u32 *)buffer);  in rng_get_data()
207 	struct hwrng *rng;  in rng_dev_read()  local
210 		rng = get_current_rng();  in rng_dev_read()
211 		if (IS_ERR(rng)) {  in rng_dev_read()
212 			err = PTR_ERR(rng);  in rng_dev_read()
215 		if (!rng) {  in rng_dev_read()
225 			bytes_read = rng_get_data(rng, rng_buffer,  in rng_dev_read()
258 		put_rng(rng);  in rng_dev_read()
274 	put_rng(rng);  in rng_dev_read()
323 	struct hwrng *rng;  in hwrng_attr_current_store()  local
332 		list_for_each_entry(rng, &rng_list, list) {  in hwrng_attr_current_store()
333 			if (sysfs_streq(rng->name, buf)) {  in hwrng_attr_current_store()
335 				err = set_current_rng(rng);  in hwrng_attr_current_store()
351 	struct hwrng *rng;  in hwrng_attr_current_show()  local
353 	rng = get_current_rng();  in hwrng_attr_current_show()
354 	if (IS_ERR(rng))  in hwrng_attr_current_show()
355 		return PTR_ERR(rng);  in hwrng_attr_current_show()
357 	ret = snprintf(buf, PAGE_SIZE, "%s\n", rng ? rng->name : "none");  in hwrng_attr_current_show()
358 	put_rng(rng);  in hwrng_attr_current_show()
368 	struct hwrng *rng;  in hwrng_attr_available_show()  local
374 	list_for_each_entry(rng, &rng_list, list) {  in hwrng_attr_available_show()
375 		strlcat(buf, rng->name, PAGE_SIZE);  in hwrng_attr_available_show()
425 		struct hwrng *rng;  in hwrng_fillfn()  local
427 		rng = get_current_rng();  in hwrng_fillfn()
428 		if (IS_ERR(rng) || !rng)  in hwrng_fillfn()
431 		rc = rng_get_data(rng, rng_fillbuf,  in hwrng_fillfn()
434 		put_rng(rng);  in hwrng_fillfn()
457 int hwrng_register(struct hwrng *rng)  in hwrng_register()  argument
463 	if (!rng->name || (!rng->data_read && !rng->read))  in hwrng_register()
470 		if (strcmp(tmp->name, rng->name) == 0)  in hwrng_register()
474 	init_completion(&rng->cleanup_done);  in hwrng_register()
475 	complete(&rng->cleanup_done);  in hwrng_register()
480 		if (tmp->quality < rng->quality)  in hwrng_register()
483 	list_add_tail(&rng->list, rng_list_ptr);  in hwrng_register()
488 	    (!cur_rng_set_by_user && rng->quality > old_rng->quality)) {  in hwrng_register()
494 		err = set_current_rng(rng);  in hwrng_register()
499 	if (old_rng && !rng->init) {  in hwrng_register()
507 		add_early_randomness(rng);  in hwrng_register()
517 void hwrng_unregister(struct hwrng *rng)  in hwrng_unregister()  argument
523 	list_del(&rng->list);  in hwrng_unregister()
524 	if (current_rng == rng) {  in hwrng_unregister()
539 	wait_for_completion(&rng->cleanup_done);  in hwrng_unregister()
558 int devm_hwrng_register(struct device *dev, struct hwrng *rng)  in devm_hwrng_register()  argument
567 	error = hwrng_register(rng);  in devm_hwrng_register()
573 	*ptr = rng;  in devm_hwrng_register()
579 void devm_hwrng_unregister(struct device *dev, struct hwrng *rng)  in devm_hwrng_unregister()  argument
581 	devres_release(dev, devm_hwrng_release, devm_hwrng_match, rng);  in devm_hwrng_unregister()