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authorTony Lindgren <tony@atomide.com>2010-03-01 17:19:05 -0500
committerTony Lindgren <tony@atomide.com>2010-03-01 17:19:05 -0500
commitd702d12167a2c05a346f49aac7a311d597762495 (patch)
treebaae42c299cce34d6df24b5d01f8b1d0b481bd9a /drivers/char/hw_random
parent9418c65f9bd861d0f7e39aab9cfb3aa6f2275d11 (diff)
parentac0f6f927db539e03e1f3f61bcd4ed57d5cde7a9 (diff)
Merge with mainline to remove plat-omap/Kconfig conflict
Conflicts: arch/arm/plat-omap/Kconfig
Diffstat (limited to 'drivers/char/hw_random')
-rw-r--r--drivers/char/hw_random/Kconfig12
-rw-r--r--drivers/char/hw_random/Makefile1
-rw-r--r--drivers/char/hw_random/nomadik-rng.c103
3 files changed, 116 insertions, 0 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index c0df30faa66a..d31483c54883 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -186,3 +186,15 @@ config HW_RANDOM_MXC_RNGA
186 module will be called mxc-rnga. 186 module will be called mxc-rnga.
187 187
188 If unsure, say Y. 188 If unsure, say Y.
189
190config HW_RANDOM_NOMADIK
191 tristate "ST-Ericsson Nomadik Random Number Generator support"
192 depends on HW_RANDOM && PLAT_NOMADIK
193 ---help---
194 This driver provides kernel-side support for the Random Number
195 Generator hardware found on ST-Ericsson SoCs (8815 and 8500).
196
197 To compile this driver as a module, choose M here: the
198 module will be called nomadik-rng.
199
200 If unsure, say Y.
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 5eeb1303f0d0..4273308aa1e3 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -18,3 +18,4 @@ obj-$(CONFIG_HW_RANDOM_VIRTIO) += virtio-rng.o
18obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o 18obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o
19obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o 19obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o
20obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o 20obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o
21obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
diff --git a/drivers/char/hw_random/nomadik-rng.c b/drivers/char/hw_random/nomadik-rng.c
new file mode 100644
index 000000000000..a8b4c4010144
--- /dev/null
+++ b/drivers/char/hw_random/nomadik-rng.c
@@ -0,0 +1,103 @@
1/*
2 * Nomadik RNG support
3 * Copyright 2009 Alessandro Rubini
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 */
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/device.h>
15#include <linux/amba/bus.h>
16#include <linux/hw_random.h>
17#include <linux/io.h>
18
19static int nmk_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
20{
21 void __iomem *base = (void __iomem *)rng->priv;
22
23 /*
24 * The register is 32 bits and gives 16 random bits (low half).
25 * A subsequent read will delay the core for 400ns, so we just read
26 * once and accept the very unlikely very small delay, even if wait==0.
27 */
28 *(u16 *)data = __raw_readl(base + 8) & 0xffff;
29 return 2;
30}
31
32/* we have at most one RNG per machine, granted */
33static struct hwrng nmk_rng = {
34 .name = "nomadik",
35 .read = nmk_rng_read,
36};
37
38static int nmk_rng_probe(struct amba_device *dev, struct amba_id *id)
39{
40 void __iomem *base;
41 int ret;
42
43 ret = amba_request_regions(dev, dev->dev.init_name);
44 if (ret)
45 return ret;
46 ret = -ENOMEM;
47 base = ioremap(dev->res.start, resource_size(&dev->res));
48 if (!base)
49 goto out_release;
50 nmk_rng.priv = (unsigned long)base;
51 ret = hwrng_register(&nmk_rng);
52 if (ret)
53 goto out_unmap;
54 return 0;
55
56out_unmap:
57 iounmap(base);
58out_release:
59 amba_release_regions(dev);
60 return ret;
61}
62
63static int nmk_rng_remove(struct amba_device *dev)
64{
65 void __iomem *base = (void __iomem *)nmk_rng.priv;
66 hwrng_unregister(&nmk_rng);
67 iounmap(base);
68 amba_release_regions(dev);
69 return 0;
70}
71
72static struct amba_id nmk_rng_ids[] = {
73 {
74 .id = 0x000805e1,
75 .mask = 0x000fffff, /* top bits are rev and cfg: accept all */
76 },
77 {0, 0},
78};
79
80static struct amba_driver nmk_rng_driver = {
81 .drv = {
82 .owner = THIS_MODULE,
83 .name = "rng",
84 },
85 .probe = nmk_rng_probe,
86 .remove = nmk_rng_remove,
87 .id_table = nmk_rng_ids,
88};
89
90static int __init nmk_rng_init(void)
91{
92 return amba_driver_register(&nmk_rng_driver);
93}
94
95static void __devexit nmk_rng_exit(void)
96{
97 amba_driver_unregister(&nmk_rng_driver);
98}
99
100module_init(nmk_rng_init);
101module_exit(nmk_rng_exit);
102
103MODULE_LICENSE("GPL");