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path: root/drivers/char/hw_random/exynos-rng.c
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Diffstat (limited to 'drivers/char/hw_random/exynos-rng.c')
-rw-r--r--drivers/char/hw_random/exynos-rng.c231
1 files changed, 0 insertions, 231 deletions
diff --git a/drivers/char/hw_random/exynos-rng.c b/drivers/char/hw_random/exynos-rng.c
deleted file mode 100644
index 23d358553b21..000000000000
--- a/drivers/char/hw_random/exynos-rng.c
+++ /dev/null
@@ -1,231 +0,0 @@
-/*
- * exynos-rng.c - Random Number Generator driver for the exynos
- *
- * Copyright (C) 2012 Samsung Electronics
- * Jonghwa Lee <jonghwa3.lee@samsung.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation;
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- */
-
-#include <linux/hw_random.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/io.h>
-#include <linux/platform_device.h>
-#include <linux/clk.h>
-#include <linux/pm_runtime.h>
-#include <linux/err.h>
-
-#define EXYNOS_PRNG_STATUS_OFFSET 0x10
-#define EXYNOS_PRNG_SEED_OFFSET 0x140
-#define EXYNOS_PRNG_OUT1_OFFSET 0x160
-#define SEED_SETTING_DONE BIT(1)
-#define PRNG_START 0x18
-#define PRNG_DONE BIT(5)
-#define EXYNOS_AUTOSUSPEND_DELAY 100
-
-struct exynos_rng {
- struct device *dev;
- struct hwrng rng;
- void __iomem *mem;
- struct clk *clk;
-};
-
-static u32 exynos_rng_readl(struct exynos_rng *rng, u32 offset)
-{
- return readl_relaxed(rng->mem + offset);
-}
-
-static void exynos_rng_writel(struct exynos_rng *rng, u32 val, u32 offset)
-{
- writel_relaxed(val, rng->mem + offset);
-}
-
-static int exynos_rng_configure(struct exynos_rng *exynos_rng)
-{
- int i;
- int ret = 0;
-
- for (i = 0 ; i < 5 ; i++)
- exynos_rng_writel(exynos_rng, jiffies,
- EXYNOS_PRNG_SEED_OFFSET + 4*i);
-
- if (!(exynos_rng_readl(exynos_rng, EXYNOS_PRNG_STATUS_OFFSET)
- & SEED_SETTING_DONE))
- ret = -EIO;
-
- return ret;
-}
-
-static int exynos_init(struct hwrng *rng)
-{
- struct exynos_rng *exynos_rng = container_of(rng,
- struct exynos_rng, rng);
- int ret = 0;
-
- pm_runtime_get_sync(exynos_rng->dev);
- ret = exynos_rng_configure(exynos_rng);
- pm_runtime_mark_last_busy(exynos_rng->dev);
- pm_runtime_put_autosuspend(exynos_rng->dev);
-
- return ret;
-}
-
-static int exynos_read(struct hwrng *rng, void *buf,
- size_t max, bool wait)
-{
- struct exynos_rng *exynos_rng = container_of(rng,
- struct exynos_rng, rng);
- u32 *data = buf;
- int retry = 100;
- int ret = 4;
-
- pm_runtime_get_sync(exynos_rng->dev);
-
- exynos_rng_writel(exynos_rng, PRNG_START, 0);
-
- while (!(exynos_rng_readl(exynos_rng,
- EXYNOS_PRNG_STATUS_OFFSET) & PRNG_DONE) && --retry)
- cpu_relax();
- if (!retry) {
- ret = -ETIMEDOUT;
- goto out;
- }
-
- exynos_rng_writel(exynos_rng, PRNG_DONE, EXYNOS_PRNG_STATUS_OFFSET);
-
- *data = exynos_rng_readl(exynos_rng, EXYNOS_PRNG_OUT1_OFFSET);
-
-out:
- pm_runtime_mark_last_busy(exynos_rng->dev);
- pm_runtime_put_sync_autosuspend(exynos_rng->dev);
-
- return ret;
-}
-
-static int exynos_rng_probe(struct platform_device *pdev)
-{
- struct exynos_rng *exynos_rng;
- struct resource *res;
- int ret;
-
- exynos_rng = devm_kzalloc(&pdev->dev, sizeof(struct exynos_rng),
- GFP_KERNEL);
- if (!exynos_rng)
- return -ENOMEM;
-
- exynos_rng->dev = &pdev->dev;
- exynos_rng->rng.name = "exynos";
- exynos_rng->rng.init = exynos_init;
- exynos_rng->rng.read = exynos_read;
- exynos_rng->clk = devm_clk_get(&pdev->dev, "secss");
- if (IS_ERR(exynos_rng->clk)) {
- dev_err(&pdev->dev, "Couldn't get clock.\n");
- return -ENOENT;
- }
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- exynos_rng->mem = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(exynos_rng->mem))
- return PTR_ERR(exynos_rng->mem);
-
- platform_set_drvdata(pdev, exynos_rng);
-
- pm_runtime_set_autosuspend_delay(&pdev->dev, EXYNOS_AUTOSUSPEND_DELAY);
- pm_runtime_use_autosuspend(&pdev->dev);
- pm_runtime_enable(&pdev->dev);
-
- ret = devm_hwrng_register(&pdev->dev, &exynos_rng->rng);
- if (ret) {
- pm_runtime_dont_use_autosuspend(&pdev->dev);
- pm_runtime_disable(&pdev->dev);
- }
-
- return ret;
-}
-
-static int exynos_rng_remove(struct platform_device *pdev)
-{
- pm_runtime_dont_use_autosuspend(&pdev->dev);
- pm_runtime_disable(&pdev->dev);
-
- return 0;
-}
-
-static int __maybe_unused exynos_rng_runtime_suspend(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
-
- clk_disable_unprepare(exynos_rng->clk);
-
- return 0;
-}
-
-static int __maybe_unused exynos_rng_runtime_resume(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
-
- return clk_prepare_enable(exynos_rng->clk);
-}
-
-static int __maybe_unused exynos_rng_suspend(struct device *dev)
-{
- return pm_runtime_force_suspend(dev);
-}
-
-static int __maybe_unused exynos_rng_resume(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
- int ret;
-
- ret = pm_runtime_force_resume(dev);
- if (ret)
- return ret;
-
- return exynos_rng_configure(exynos_rng);
-}
-
-static const struct dev_pm_ops exynos_rng_pm_ops = {
- SET_SYSTEM_SLEEP_PM_OPS(exynos_rng_suspend, exynos_rng_resume)
- SET_RUNTIME_PM_OPS(exynos_rng_runtime_suspend,
- exynos_rng_runtime_resume, NULL)
-};
-
-static const struct of_device_id exynos_rng_dt_match[] = {
- {
- .compatible = "samsung,exynos4-rng",
- },
- { },
-};
-MODULE_DEVICE_TABLE(of, exynos_rng_dt_match);
-
-static struct platform_driver exynos_rng_driver = {
- .driver = {
- .name = "exynos-rng",
- .pm = &exynos_rng_pm_ops,
- .of_match_table = exynos_rng_dt_match,
- },
- .probe = exynos_rng_probe,
- .remove = exynos_rng_remove,
-};
-
-module_platform_driver(exynos_rng_driver);
-
-MODULE_DESCRIPTION("EXYNOS 4 H/W Random Number Generator driver");
-MODULE_AUTHOR("Jonghwa Lee <jonghwa3.lee@samsung.com>");
-MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-26 15:01:27 +0000