2 * RNG driver for Moschip MCS814x SoC
4 * Copyright 2012 (C), Florian Fainelli <florian@openwrt.org>
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/platform_device.h>
16 #include <linux/hw_random.h>
23 struct mcs814x_rng_priv {
27 static int mcs814x_rng_data_read(struct hwrng *rng, u32 *buffer)
29 struct mcs814x_rng_priv *priv = (struct mcs814x_rng_priv *)rng->priv;
31 *buffer = __raw_readl(priv->regs + RND);
36 static int mcs814x_rng_probe(struct platform_device *pdev)
39 struct mcs814x_rng_priv *priv;
43 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
47 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
53 rng = kzalloc(sizeof(*rng), GFP_KERNEL);
59 platform_set_drvdata(pdev, rng);
60 rng->priv = (unsigned long)priv;
61 rng->name = pdev->name;
62 rng->data_read = mcs814x_rng_data_read;
64 if (!devm_request_mem_region(&pdev->dev,
65 res->start, resource_size(res),
71 priv->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
77 ret = hwrng_register(rng);
79 dev_err(&pdev->dev, "failed to register hwrng driver\n");
83 dev_info(&pdev->dev, "registered\n");
88 platform_set_drvdata(pdev, NULL);
96 static int mcs814x_rng_remove(struct platform_device *pdev)
98 struct hwrng *rng = platform_get_drvdata(pdev);
99 struct mcs814x_rng_priv *priv = (struct mcs814x_rng_priv *)rng->priv;
101 hwrng_unregister(rng);
104 platform_set_drvdata(pdev, NULL);
109 static const struct of_device_id mcs814x_rng_ids[] = {
110 { .compatible = "moschip,mcs814x-rng", },
114 static struct platform_driver mcs814x_rng_driver = {
116 .name = "mcs814x-rng",
117 .owner = THIS_MODULE,
118 .of_match_table = mcs814x_rng_ids,
120 .probe = mcs814x_rng_probe,
121 .remove = __devexit_p(mcs814x_rng_remove),
124 module_platform_driver(mcs814x_rng_driver);
126 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
127 MODULE_DESCRIPTION("H/W Random Number Generator (RNG) for Moschip MCS814x");
128 MODULE_LICENSE("GPL");