59  * struct stm32_rng_config - RNG configuration data
61  * @cr:			RNG configuration. 0 means default hardware RNG configuration
72 	struct hwrng rng;  member
83  * Extracts from the STM32 RNG specification when RNG supports CONDRST.
85  * When a noise source (or seed) error occurs, the RNG stops generating
91  * Indeed, when SEIS is set and SECS is cleared it means RNG performed
98  * cleared by RNG. The random number generation is now back to normal.
102 	struct device *dev = (struct device *)priv->rng.priv;  in stm32_rng_conceal_seed_error_cond_reset()
112 		/* RNG auto-reset (step 2.) */  in stm32_rng_conceal_seed_error_cond_reset()
140  * Extracts from the STM32 RNG specification, when CONDRST is not supported
142  * When a noise source (or seed) error occurs, the RNG stops generating
147  * error after the RNG initialization:
170 static int stm32_rng_conceal_seed_error(struct hwrng *rng)  in stm32_rng_conceal_seed_error()  argument
172 	struct stm32_rng_private *priv = container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_conceal_seed_error()
174 	dev_dbg((struct device *)priv->rng.priv, "Concealing seed error\n");  in stm32_rng_conceal_seed_error()
183 static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)  in stm32_rng_read()  argument
185 	struct stm32_rng_private *priv = container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_read()
190 	pm_runtime_get_sync((struct device *) priv->rng.priv);  in stm32_rng_read()
193 		stm32_rng_conceal_seed_error(rng);  in stm32_rng_read()
199 		 * care of initial delay time when enabling the RNG.  in stm32_rng_read()
207 				dev_err((struct device *)priv->rng.priv,  in stm32_rng_read()
218 				err = stm32_rng_conceal_seed_error(rng);  in stm32_rng_read()
221 					dev_err((struct device *)priv->rng.priv,  in stm32_rng_read()
229 			if (WARN_ONCE((sr & RNG_SR_CEIS), "RNG clock too slow - %x\n", sr))  in stm32_rng_read()
236 			err = stm32_rng_conceal_seed_error(rng);  in stm32_rng_read()
239 				dev_err((struct device *)priv->rng.priv,  in stm32_rng_read()
253 	pm_runtime_mark_last_busy((struct device *) priv->rng.priv);  in stm32_rng_read()
254 	pm_runtime_put_sync_autosuspend((struct device *) priv->rng.priv);  in stm32_rng_read()
259 static uint stm32_rng_clock_freq_restrain(struct hwrng *rng)  in stm32_rng_clock_freq_restrain()  argument
262 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_clock_freq_restrain()
276 	pr_debug("RNG clk rate : %lu\n", clk_get_rate(priv->clk) >> clock_div);  in stm32_rng_clock_freq_restrain()
281 static int stm32_rng_init(struct hwrng *rng)  in stm32_rng_init()  argument
284 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_init()
298 	 * Keep default RNG configuration if none was specified.  in stm32_rng_init()
302 		uint clock_div = stm32_rng_clock_freq_restrain(rng);  in stm32_rng_init()
329 			dev_err((struct device *)priv->rng.priv,  in stm32_rng_init()
334 		/* Handle all RNG versions by checking if conditional reset should be set */  in stm32_rng_init()
358 		dev_err((struct device *)priv->rng.priv,  in stm32_rng_init()
393 	/* Do not save that RNG is enabled as it will be handled at resume */  in stm32_rng_suspend()
458 			dev_err((struct device *)priv->rng.priv,  in stm32_rng_resume()
493 		.compatible = "st,stm32mp13-rng",
497 		.compatible = "st,stm32-rng",
531 	priv->lock_conf = of_property_read_bool(np, "st,rng-lock-conf");  in stm32_rng_probe()
539 	priv->rng.name = dev_driver_string(dev);  in stm32_rng_probe()
540 	priv->rng.init = stm32_rng_init;  in stm32_rng_probe()
541 	priv->rng.read = stm32_rng_read;  in stm32_rng_probe()
542 	priv->rng.priv = (unsigned long) dev;  in stm32_rng_probe()
543 	priv->rng.quality = 900;  in stm32_rng_probe()
549 	return devm_hwrng_register(dev, &priv->rng);  in stm32_rng_probe()
554 		.name = "stm32-rng",
566 MODULE_DESCRIPTION("STMicroelectronics STM32 RNG device driver");