0788257aee
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>
130 lines
3.4 KiB
C
130 lines
3.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Ingenic True Random Number Generator driver
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* Copyright (c) 2019 漆鹏振 (Qi Pengzhen) <aric.pzqi@ingenic.com>
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* Copyright (c) 2020 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
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*/
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#include <linux/clk.h>
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#include <linux/err.h>
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#include <linux/kernel.h>
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#include <linux/hw_random.h>
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#include <linux/io.h>
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#include <linux/iopoll.h>
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#include <linux/mod_devicetable.h>
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#include <linux/module.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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/* DTRNG register offsets */
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#define TRNG_REG_CFG_OFFSET 0x00
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#define TRNG_REG_RANDOMNUM_OFFSET 0x04
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#define TRNG_REG_STATUS_OFFSET 0x08
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/* bits within the CFG register */
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#define CFG_GEN_EN BIT(0)
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/* bits within the STATUS register */
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#define STATUS_RANDOM_RDY BIT(0)
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struct ingenic_trng {
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void __iomem *base;
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struct hwrng rng;
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};
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static int ingenic_trng_init(struct hwrng *rng)
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{
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struct ingenic_trng *trng = container_of(rng, struct ingenic_trng, rng);
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unsigned int ctrl;
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ctrl = readl(trng->base + TRNG_REG_CFG_OFFSET);
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ctrl |= CFG_GEN_EN;
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writel(ctrl, trng->base + TRNG_REG_CFG_OFFSET);
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return 0;
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}
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static void ingenic_trng_cleanup(struct hwrng *rng)
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{
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struct ingenic_trng *trng = container_of(rng, struct ingenic_trng, rng);
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unsigned int ctrl;
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ctrl = readl(trng->base + TRNG_REG_CFG_OFFSET);
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ctrl &= ~CFG_GEN_EN;
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writel(ctrl, trng->base + TRNG_REG_CFG_OFFSET);
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}
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static int ingenic_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
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{
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struct ingenic_trng *trng = container_of(rng, struct ingenic_trng, rng);
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u32 *data = buf;
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u32 status;
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int ret;
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ret = readl_poll_timeout(trng->base + TRNG_REG_STATUS_OFFSET, status,
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status & STATUS_RANDOM_RDY, 10, 1000);
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if (ret == -ETIMEDOUT) {
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pr_err("%s: Wait for DTRNG data ready timeout\n", __func__);
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return ret;
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}
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*data = readl(trng->base + TRNG_REG_RANDOMNUM_OFFSET);
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return 4;
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}
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static int ingenic_trng_probe(struct platform_device *pdev)
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{
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struct ingenic_trng *trng;
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struct clk *clk;
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int ret;
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trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
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if (!trng)
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return -ENOMEM;
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trng->base = devm_platform_ioremap_resource(pdev, 0);
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if (IS_ERR(trng->base))
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return dev_err_probe(&pdev->dev, PTR_ERR(trng->base),
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"%s: Failed to map DTRNG registers\n", __func__);
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clk = devm_clk_get_enabled(&pdev->dev, NULL);
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if (IS_ERR(clk))
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return dev_err_probe(&pdev->dev, PTR_ERR(clk),
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"%s: Cannot get and enable DTRNG clock\n", __func__);
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trng->rng.name = pdev->name;
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trng->rng.init = ingenic_trng_init;
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trng->rng.cleanup = ingenic_trng_cleanup;
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trng->rng.read = ingenic_trng_read;
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ret = devm_hwrng_register(&pdev->dev, &trng->rng);
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if (ret)
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return dev_err_probe(&pdev->dev, ret, "Failed to register hwrng\n");
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platform_set_drvdata(pdev, trng);
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dev_info(&pdev->dev, "Ingenic DTRNG driver registered\n");
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return 0;
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}
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static const struct of_device_id ingenic_trng_of_match[] = {
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{ .compatible = "ingenic,x1830-dtrng" },
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{ /* sentinel */ }
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};
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MODULE_DEVICE_TABLE(of, ingenic_trng_of_match);
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static struct platform_driver ingenic_trng_driver = {
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.probe = ingenic_trng_probe,
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.driver = {
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.name = "ingenic-trng",
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.of_match_table = ingenic_trng_of_match,
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},
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};
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module_platform_driver(ingenic_trng_driver);
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("漆鹏振 (Qi Pengzhen) <aric.pzqi@ingenic.com>");
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MODULE_AUTHOR("周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>");
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MODULE_DESCRIPTION("Ingenic True Random Number Generator driver");
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