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
= readl_relaxed(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");