linux-IllusionX/drivers/char/hw_random/pasemi-rng.c
Rob Herring 0788257aee hwrng: Explicitly include correct DT includes
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it was merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-08-04 17:09:26 +08:00

118 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2006-2007 PA Semi, Inc
*
* Maintained by: Olof Johansson <olof@lixom.net>
*
* Driver for the PWRficient onchip rng
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/hw_random.h>
#include <linux/delay.h>
#include <linux/io.h>
#define SDCRNG_CTL_REG 0x00
#define SDCRNG_CTL_FVLD_M 0x0000f000
#define SDCRNG_CTL_FVLD_S 12
#define SDCRNG_CTL_KSZ 0x00000800
#define SDCRNG_CTL_RSRC_CRG 0x00000010
#define SDCRNG_CTL_RSRC_RRG 0x00000000
#define SDCRNG_CTL_CE 0x00000004
#define SDCRNG_CTL_RE 0x00000002
#define SDCRNG_CTL_DR 0x00000001
#define SDCRNG_CTL_SELECT_RRG_RNG (SDCRNG_CTL_RE | SDCRNG_CTL_RSRC_RRG)
#define SDCRNG_CTL_SELECT_CRG_RNG (SDCRNG_CTL_CE | SDCRNG_CTL_RSRC_CRG)
#define SDCRNG_VAL_REG 0x20
#define MODULE_NAME "pasemi_rng"
static int pasemi_rng_data_present(struct hwrng *rng, int wait)
{
void __iomem *rng_regs = (void __iomem *)rng->priv;
int data, i;
for (i = 0; i < 20; i++) {
data = (in_le32(rng_regs + SDCRNG_CTL_REG)
& SDCRNG_CTL_FVLD_M) ? 1 : 0;
if (data || !wait)
break;
udelay(10);
}
return data;
}
static int pasemi_rng_data_read(struct hwrng *rng, u32 *data)
{
void __iomem *rng_regs = (void __iomem *)rng->priv;
*data = in_le32(rng_regs + SDCRNG_VAL_REG);
return 4;
}
static int pasemi_rng_init(struct hwrng *rng)
{
void __iomem *rng_regs = (void __iomem *)rng->priv;
u32 ctl;
ctl = SDCRNG_CTL_DR | SDCRNG_CTL_SELECT_RRG_RNG | SDCRNG_CTL_KSZ;
out_le32(rng_regs + SDCRNG_CTL_REG, ctl);
out_le32(rng_regs + SDCRNG_CTL_REG, ctl & ~SDCRNG_CTL_DR);
return 0;
}
static void pasemi_rng_cleanup(struct hwrng *rng)
{
void __iomem *rng_regs = (void __iomem *)rng->priv;
u32 ctl;
ctl = SDCRNG_CTL_RE | SDCRNG_CTL_CE;
out_le32(rng_regs + SDCRNG_CTL_REG,
in_le32(rng_regs + SDCRNG_CTL_REG) & ~ctl);
}
static struct hwrng pasemi_rng = {
.name = MODULE_NAME,
.init = pasemi_rng_init,
.cleanup = pasemi_rng_cleanup,
.data_present = pasemi_rng_data_present,
.data_read = pasemi_rng_data_read,
};
static int rng_probe(struct platform_device *pdev)
{
void __iomem *rng_regs;
rng_regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(rng_regs))
return PTR_ERR(rng_regs);
pasemi_rng.priv = (unsigned long)rng_regs;
pr_info("Registering PA Semi RNG\n");
return devm_hwrng_register(&pdev->dev, &pasemi_rng);
}
static const struct of_device_id rng_match[] = {
{ .compatible = "1682m-rng", },
{ .compatible = "pasemi,pwrficient-rng", },
{ },
};
MODULE_DEVICE_TABLE(of, rng_match);
static struct platform_driver rng_driver = {
.driver = {
.name = "pasemi-rng",
.of_match_table = rng_match,
},
.probe = rng_probe,
};
module_platform_driver(rng_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
MODULE_DESCRIPTION("H/W RNG driver for PA Semi processor");