40 	struct hwrng rng;  member
47 static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)  in stm32_rng_read()  argument
50 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_read()
54 	pm_runtime_get_sync((struct device *) priv->rng.priv);  in stm32_rng_read()
57 		sr = readl_relaxed(priv->base + RNG_SR);  in stm32_rng_read()
59 		/* care of initial delay time when enabling rng	*/  in stm32_rng_read()
61 			retval = readl_relaxed_poll_timeout_atomic(priv->base  in stm32_rng_read()
66 				dev_err((struct device *)priv->rng.priv,  in stm32_rng_read()
73 					"bad RNG status - %x\n", sr))  in stm32_rng_read()
74 				writel_relaxed(0, priv->base + RNG_SR);  in stm32_rng_read()
78 		*(u32 *)data = readl_relaxed(priv->base + RNG_DR);  in stm32_rng_read()
82 		max -= sizeof(u32);  in stm32_rng_read()
85 	pm_runtime_mark_last_busy((struct device *) priv->rng.priv);  in stm32_rng_read()
86 	pm_runtime_put_sync_autosuspend((struct device *) priv->rng.priv);  in stm32_rng_read()
88 	return retval || !wait ? retval : -EIO;  in stm32_rng_read()
91 static int stm32_rng_init(struct hwrng *rng)  in stm32_rng_init()  argument
94 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_init()
97 	err = clk_prepare_enable(priv->clk);  in stm32_rng_init()
101 	if (priv->ced)  in stm32_rng_init()
102 		writel_relaxed(RNG_CR_RNGEN, priv->base + RNG_CR);  in stm32_rng_init()
105 			       priv->base + RNG_CR);  in stm32_rng_init()
108 	writel_relaxed(0, priv->base + RNG_SR);  in stm32_rng_init()
113 static void stm32_rng_cleanup(struct hwrng *rng)  in stm32_rng_cleanup()  argument
116 	    container_of(rng, struct stm32_rng_private, rng);  in stm32_rng_cleanup()
118 	writel_relaxed(0, priv->base + RNG_CR);  in stm32_rng_cleanup()
119 	clk_disable_unprepare(priv->clk);  in stm32_rng_cleanup()
124 	struct device *dev = &ofdev->dev;  in stm32_rng_probe()
125 	struct device_node *np = ofdev->dev.of_node;  in stm32_rng_probe()
132 		return -ENOMEM;  in stm32_rng_probe()
138 	priv->base = devm_ioremap_resource(dev, &res);  in stm32_rng_probe()
139 	if (IS_ERR(priv->base))  in stm32_rng_probe()
140 		return PTR_ERR(priv->base);  in stm32_rng_probe()
142 	priv->clk = devm_clk_get(&ofdev->dev, NULL);  in stm32_rng_probe()
143 	if (IS_ERR(priv->clk))  in stm32_rng_probe()
144 		return PTR_ERR(priv->clk);  in stm32_rng_probe()
146 	priv->rst = devm_reset_control_get(&ofdev->dev, NULL);  in stm32_rng_probe()
147 	if (!IS_ERR(priv->rst)) {  in stm32_rng_probe()
148 		reset_control_assert(priv->rst);  in stm32_rng_probe()
150 		reset_control_deassert(priv->rst);  in stm32_rng_probe()
153 	priv->ced = of_property_read_bool(np, "clock-error-detect");  in stm32_rng_probe()
157 	priv->rng.name = dev_driver_string(dev),  in stm32_rng_probe()
159 	priv->rng.init = stm32_rng_init,  in stm32_rng_probe()
160 	priv->rng.cleanup = stm32_rng_cleanup,  in stm32_rng_probe()
162 	priv->rng.read = stm32_rng_read,  in stm32_rng_probe()
163 	priv->rng.priv = (unsigned long) dev;  in stm32_rng_probe()
169 	return devm_hwrng_register(dev, &priv->rng);  in stm32_rng_probe()
174 	pm_runtime_disable(&ofdev->dev);  in stm32_rng_remove()
184 	stm32_rng_cleanup(&priv->rng);  in stm32_rng_runtime_suspend()
193 	return stm32_rng_init(&priv->rng);  in stm32_rng_runtime_resume()
207 		.compatible = "st,stm32-rng",
215 		.name = "stm32-rng",
227 MODULE_DESCRIPTION("STMicroelectronics STM32 RNG device driver");