59  * struct stm32_rng_config - RNG configuration data
61  * @cr:			RNG configuration. 0 means default hardware RNG configuration
72 	struct hwrng rng;  member
84  * Extracts from the STM32 RNG specification when RNG supports CONDRST.
86  * When a noise source (or seed) error occurs, the RNG stops generating
92  * Indeed, when SEIS is set and SECS is cleared it means RNG performed
99  * cleared by RNG. The random number generation is now back to normal.
113 		/* RNG auto-reset (step 2.) */  in stm32_rng_conceal_seed_error_cond_reset()
141  * Extracts from the STM32 RNG specification, when CONDRST is not supported
143  * When a noise source (or seed) error occurs, the RNG stops generating
148  * error after the RNG initialization:
171 static int stm32_rng_conceal_seed_error(struct hwrng *rng)  in stm32_rng_conceal_seed_error()  argument
173 	struct stm32_rng_private *priv = container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_conceal_seed_error()
184 static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)  in stm32_rng_read()  argument
186 	struct stm32_rng_private *priv = container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_read()
196 		stm32_rng_conceal_seed_error(rng);  in stm32_rng_read()
202 		 * care of initial delay time when enabling the RNG.  in stm32_rng_read()
220 				err = stm32_rng_conceal_seed_error(rng);  in stm32_rng_read()
231 			if (WARN_ONCE((sr & RNG_SR_CEIS), "RNG clock too slow - %x\n", sr))  in stm32_rng_read()
238 			err = stm32_rng_conceal_seed_error(rng);  in stm32_rng_read()
262 static uint stm32_rng_clock_freq_restrain(struct hwrng *rng)  in stm32_rng_clock_freq_restrain()  argument
265 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_clock_freq_restrain()
279 	pr_debug("RNG clk rate : %lu\n", clk_get_rate(priv->clk) >> clock_div);  in stm32_rng_clock_freq_restrain()
284 static int stm32_rng_init(struct hwrng *rng)  in stm32_rng_init()  argument
287 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_init()
301 	 * Keep default RNG configuration if none was specified.  in stm32_rng_init()
305 		uint clock_div = stm32_rng_clock_freq_restrain(rng);  in stm32_rng_init()
336 		/* Handle all RNG versions by checking if conditional reset should be set */  in stm32_rng_init()
401 	/* Do not save that RNG is enabled as it will be handled at resume */  in stm32_rng_suspend()
502 		.compatible = "st,stm32mp13-rng",
506 		.compatible = "st,stm32-rng",
540 	priv->lock_conf = of_property_read_bool(np, "st,rng-lock-conf");  in stm32_rng_probe()
549 	priv->rng.name = dev_driver_string(dev);  in stm32_rng_probe()
550 	priv->rng.init = stm32_rng_init;  in stm32_rng_probe()
551 	priv->rng.read = stm32_rng_read;  in stm32_rng_probe()
552 	priv->rng.quality = 900;  in stm32_rng_probe()
558 	return devm_hwrng_register(dev, &priv->rng);  in stm32_rng_probe()
563 		.name = "stm32-rng",
575 MODULE_DESCRIPTION("STMicroelectronics STM32 RNG device driver");