mirror of
https://github.com/torvalds/linux.git
synced 2024-12-17 08:31:39 +00:00
b21cb324f1
This patch converts the drivers in drivers/char/hw_random/* to use the module_platform_driver() macro which makes the code smaller and a bit simpler. Cc: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Jamie Iles <jamie@jamieiles.com> Acked-by: Alexander Clouter <alex@digriz.org.uk> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: David Daney <david.daney@cavium.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
149 lines
3.1 KiB
C
149 lines
3.1 KiB
C
/*
|
|
* Copyright (c) 2011 Peter Korsgaard <jacmet@sunsite.dk>
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/err.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/io.h>
|
|
#include <linux/hw_random.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
#define TRNG_CR 0x00
|
|
#define TRNG_ISR 0x1c
|
|
#define TRNG_ODATA 0x50
|
|
|
|
#define TRNG_KEY 0x524e4700 /* RNG */
|
|
|
|
struct atmel_trng {
|
|
struct clk *clk;
|
|
void __iomem *base;
|
|
struct hwrng rng;
|
|
};
|
|
|
|
static int atmel_trng_read(struct hwrng *rng, void *buf, size_t max,
|
|
bool wait)
|
|
{
|
|
struct atmel_trng *trng = container_of(rng, struct atmel_trng, rng);
|
|
u32 *data = buf;
|
|
|
|
/* data ready? */
|
|
if (readl(trng->base + TRNG_ODATA) & 1) {
|
|
*data = readl(trng->base + TRNG_ODATA);
|
|
return 4;
|
|
} else
|
|
return 0;
|
|
}
|
|
|
|
static int atmel_trng_probe(struct platform_device *pdev)
|
|
{
|
|
struct atmel_trng *trng;
|
|
struct resource *res;
|
|
int ret;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!res)
|
|
return -EINVAL;
|
|
|
|
trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
|
|
if (!trng)
|
|
return -ENOMEM;
|
|
|
|
if (!devm_request_mem_region(&pdev->dev, res->start,
|
|
resource_size(res), pdev->name))
|
|
return -EBUSY;
|
|
|
|
trng->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
|
|
if (!trng->base)
|
|
return -EBUSY;
|
|
|
|
trng->clk = clk_get(&pdev->dev, NULL);
|
|
if (IS_ERR(trng->clk))
|
|
return PTR_ERR(trng->clk);
|
|
|
|
ret = clk_enable(trng->clk);
|
|
if (ret)
|
|
goto err_enable;
|
|
|
|
writel(TRNG_KEY | 1, trng->base + TRNG_CR);
|
|
trng->rng.name = pdev->name;
|
|
trng->rng.read = atmel_trng_read;
|
|
|
|
ret = hwrng_register(&trng->rng);
|
|
if (ret)
|
|
goto err_register;
|
|
|
|
platform_set_drvdata(pdev, trng);
|
|
|
|
return 0;
|
|
|
|
err_register:
|
|
clk_disable(trng->clk);
|
|
err_enable:
|
|
clk_put(trng->clk);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int __devexit atmel_trng_remove(struct platform_device *pdev)
|
|
{
|
|
struct atmel_trng *trng = platform_get_drvdata(pdev);
|
|
|
|
hwrng_unregister(&trng->rng);
|
|
|
|
writel(TRNG_KEY, trng->base + TRNG_CR);
|
|
clk_disable(trng->clk);
|
|
clk_put(trng->clk);
|
|
|
|
platform_set_drvdata(pdev, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int atmel_trng_suspend(struct device *dev)
|
|
{
|
|
struct atmel_trng *trng = dev_get_drvdata(dev);
|
|
|
|
clk_disable(trng->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int atmel_trng_resume(struct device *dev)
|
|
{
|
|
struct atmel_trng *trng = dev_get_drvdata(dev);
|
|
|
|
return clk_enable(trng->clk);
|
|
}
|
|
|
|
static const struct dev_pm_ops atmel_trng_pm_ops = {
|
|
.suspend = atmel_trng_suspend,
|
|
.resume = atmel_trng_resume,
|
|
};
|
|
#endif /* CONFIG_PM */
|
|
|
|
static struct platform_driver atmel_trng_driver = {
|
|
.probe = atmel_trng_probe,
|
|
.remove = __devexit_p(atmel_trng_remove),
|
|
.driver = {
|
|
.name = "atmel-trng",
|
|
.owner = THIS_MODULE,
|
|
#ifdef CONFIG_PM
|
|
.pm = &atmel_trng_pm_ops,
|
|
#endif /* CONFIG_PM */
|
|
},
|
|
};
|
|
|
|
module_platform_driver(atmel_trng_driver);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
|
|
MODULE_DESCRIPTION("Atmel true random number generator driver");
|