Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Copyright (c) 2016 BayLibre, SAS.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  * Author: Neil Armstrong <narmstrong@baylibre.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Copyright (C) 2014 Amlogic, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/hw_random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/of.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/clk.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #define RNG_DATA 0x00
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) struct meson_rng_data {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	void __iomem *base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	struct platform_device *pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	struct hwrng rng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	struct clk *core_clk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	struct meson_rng_data *data =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 			container_of(rng, struct meson_rng_data, rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	*(u32 *)buf = readl_relaxed(data->base + RNG_DATA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	return sizeof(u32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) static void meson_rng_clk_disable(void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	clk_disable_unprepare(data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) static int meson_rng_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	struct meson_rng_data *data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	if (!data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	data->pdev = pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	data->base = devm_platform_ioremap_resource(pdev, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 	if (IS_ERR(data->base))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 		return PTR_ERR(data->base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 	data->core_clk = devm_clk_get(dev, "core");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	if (IS_ERR(data->core_clk))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 		data->core_clk = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	if (data->core_clk) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		ret = clk_prepare_enable(data->core_clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 			return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 		ret = devm_add_action_or_reset(dev, meson_rng_clk_disable,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 					       data->core_clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 			return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	data->rng.name = pdev->name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 	data->rng.read = meson_rng_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 	platform_set_drvdata(pdev, data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 	return devm_hwrng_register(dev, &data->rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) static const struct of_device_id meson_rng_of_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 	{ .compatible = "amlogic,meson-rng", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 	{},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) MODULE_DEVICE_TABLE(of, meson_rng_of_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) static struct platform_driver meson_rng_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) 	.probe	= meson_rng_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 	.driver	= {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 		.name = "meson-rng",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 		.of_match_table = meson_rng_of_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) module_platform_driver(meson_rng_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) MODULE_DESCRIPTION("Meson H/W Random Number Generator driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) MODULE_AUTHOR("Lawrence Mok <lawrence.mok@amlogic.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) MODULE_LICENSE("Dual BSD/GPL");