3 files changed, 58 insertions, 2 deletions

diff --git a/drivers/char/hw_random/mtk-rng.c b/drivers/char/hw_random/mtk-rng.c
index df8eb54fd5a3..8da7bcf54105 100644
--- a/drivers/char/hw_random/mtk-rng.c
+++ b/drivers/char/hw_random/mtk-rng.c
@@ -25,6 +25,10 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+/* Runtime PM autosuspend timeout: */
+#define RNG_AUTOSUSPEND_TIMEOUT		100
 
 #define USEC_POLL			2
 #define TIMEOUT_POLL			20
@@ -90,6 +94,8 @@ static int mtk_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
 	struct mtk_rng *priv = to_mtk_rng(rng);
 	int retval = 0;
 
+	pm_runtime_get_sync((struct device *)priv->rng.priv);
+
 	while (max >= sizeof(u32)) {
 		if (!mtk_rng_wait_ready(rng, wait))
 			break;
@@ -100,6 +106,9 @@ static int mtk_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
 		max -= sizeof(u32);
 	}
 
+	pm_runtime_mark_last_busy((struct device *)priv->rng.priv);
+	pm_runtime_put_sync_autosuspend((struct device *)priv->rng.priv);
+
 	return retval || !wait ? retval : -EIO;
 }
 
@@ -120,9 +129,12 @@ static int mtk_rng_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	priv->rng.name = pdev->name;
+#ifndef CONFIG_PM
 	priv->rng.init = mtk_rng_init;
 	priv->rng.cleanup = mtk_rng_cleanup;
+#endif
 	priv->rng.read = mtk_rng_read;
+	priv->rng.priv = (unsigned long)&pdev->dev;
 
 	priv->clk = devm_clk_get(&pdev->dev, "rng");
 	if (IS_ERR(priv->clk)) {
@@ -142,11 +154,40 @@ static int mtk_rng_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	dev_set_drvdata(&pdev->dev, priv);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, RNG_AUTOSUSPEND_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
 	dev_info(&pdev->dev, "registered RNG driver\n");
 
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int mtk_rng_runtime_suspend(struct device *dev)
+{
+	struct mtk_rng *priv = dev_get_drvdata(dev);
+
+	mtk_rng_cleanup(&priv->rng);
+
+	return 0;
+}
+
+static int mtk_rng_runtime_resume(struct device *dev)
+{
+	struct mtk_rng *priv = dev_get_drvdata(dev);
+
+	return mtk_rng_init(&priv->rng);
+}
+
+static UNIVERSAL_DEV_PM_OPS(mtk_rng_pm_ops, mtk_rng_runtime_suspend,
+			    mtk_rng_runtime_resume, NULL);
+#define MTK_RNG_PM_OPS (&mtk_rng_pm_ops)
+#else	/* CONFIG_PM */
+#define MTK_RNG_PM_OPS NULL
+#endif	/* CONFIG_PM */
+
 static const struct of_device_id mtk_rng_match[] = {
 	{ .compatible = "mediatek,mt7623-rng" },
 	{},
@@ -157,6 +198,7 @@ static struct platform_driver mtk_rng_driver = {
 	.probe          = mtk_rng_probe,
 	.driver = {
 		.name = MTK_RNG_DEV,
+		.pm = MTK_RNG_PM_OPS,
 		.of_match_table = mtk_rng_match,
 	},
 };
diff --git a/drivers/char/hw_random/omap3-rom-rng.c b/drivers/char/hw_random/omap3-rom-rng.c
index 37a58d78aab3..38b719017186 100644
--- a/drivers/char/hw_random/omap3-rom-rng.c
+++ b/drivers/char/hw_random/omap3-rom-rng.c
@@ -53,7 +53,10 @@ static int omap3_rom_rng_get_random(void *buf, unsigned int count)
 
 	cancel_delayed_work_sync(&idle_work);
 	if (rng_idle) {
-		clk_prepare_enable(rng_clk);
+		r = clk_prepare_enable(rng_clk);
+		if (r)
+			return r;
+
 		r = omap3_rom_rng_call(0, 0, RNG_GEN_PRNG_HW_INIT);
 		if (r != 0) {
 			clk_disable_unprepare(rng_clk);
@@ -88,6 +91,8 @@ static struct hwrng omap3_rom_rng_ops = {
 
 static int omap3_rom_rng_probe(struct platform_device *pdev)
 {
+	int ret = 0;
+
 	pr_info("initializing\n");
 
 	omap3_rom_rng_call = pdev->dev.platform_data;
@@ -104,7 +109,9 @@ static int omap3_rom_rng_probe(struct platform_device *pdev)
 	}
 
 	/* Leave the RNG in reset state. */
-	clk_prepare_enable(rng_clk);
+	ret = clk_prepare_enable(rng_clk);
+	if (ret)
+		return ret;
 	omap3_rom_rng_idle(0);
 
 	return hwrng_register(&omap3_rom_rng_ops);
diff --git a/drivers/char/hw_random/timeriomem-rng.c b/drivers/char/hw_random/timeriomem-rng.c
index a0faa5f05deb..03ff5483d865 100644
--- a/drivers/char/hw_random/timeriomem-rng.c
+++ b/drivers/char/hw_random/timeriomem-rng.c
@@ -151,8 +151,15 @@ static int timeriomem_rng_probe(struct platform_device *pdev)
 			dev_err(&pdev->dev, "missing period\n");
 			return -EINVAL;
 		}
+
+		if (!of_property_read_u32(pdev->dev.of_node,
+						"quality", &i))
+			priv->rng_ops.quality = i;
+		else
+			priv->rng_ops.quality = 0;
 	} else {
 		period = pdata->period;
+		priv->rng_ops.quality = pdata->quality;
 	}
 
 	priv->period = ns_to_ktime(period * NSEC_PER_USEC);