[linux-block.git] / drivers / nvmem / meson-efuse.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Amlogic Meson GX eFuse Driver
 *
 * Copyright (c) 2016 Endless Computers, Inc.
 * Author: Carlo Caione <carlo@endlessm.com>
 */

#include <linux/clk.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/platform_device.h>

#include <linux/firmware/meson/meson_sm.h>

static int meson_efuse_read(void *context, unsigned int offset,
			    void *val, size_t bytes)
{
	struct meson_sm_firmware *fw = context;

	return meson_sm_call_read(fw, (u8 *)val, bytes, SM_EFUSE_READ, offset,
				  bytes, 0, 0, 0);
}

static int meson_efuse_write(void *context, unsigned int offset,
			     void *val, size_t bytes)
{
	struct meson_sm_firmware *fw = context;

	return meson_sm_call_write(fw, (u8 *)val, bytes, SM_EFUSE_WRITE, offset,
				   bytes, 0, 0, 0);
}

static const struct of_device_id meson_efuse_match[] = {
	{ .compatible = "amlogic,meson-gxbb-efuse", },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, meson_efuse_match);

static int meson_efuse_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct meson_sm_firmware *fw;
	struct device_node *sm_np;
	struct nvmem_device *nvmem;
	struct nvmem_config *econfig;
	struct clk *clk;
	unsigned int size;
	int ret;

	sm_np = of_parse_phandle(pdev->dev.of_node, "secure-monitor", 0);
	if (!sm_np) {
		dev_err(&pdev->dev, "no secure-monitor node\n");
		return -ENODEV;
	}

	fw = meson_sm_get(sm_np);
	of_node_put(sm_np);
	if (!fw)
		return -EPROBE_DEFER;

	clk = devm_clk_get(dev, NULL);
	if (IS_ERR(clk)) {
		ret = PTR_ERR(clk);
		if (ret != -EPROBE_DEFER)
			dev_err(dev, "failed to get efuse gate");
		return ret;
	}

	ret = clk_prepare_enable(clk);
	if (ret) {
		dev_err(dev, "failed to enable gate");
		return ret;
	}

	ret = devm_add_action_or_reset(dev,
				       (void(*)(void *))clk_disable_unprepare,
				       clk);
	if (ret) {
		dev_err(dev, "failed to add disable callback");
		return ret;
	}

	if (meson_sm_call(fw, SM_EFUSE_USER_MAX, &size, 0, 0, 0, 0, 0) < 0) {
		dev_err(dev, "failed to get max user");
		return -EINVAL;
	}

	econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
	if (!econfig)
		return -ENOMEM;

	econfig->dev = dev;
	econfig->name = dev_name(dev);
	econfig->stride = 1;
	econfig->word_size = 1;
	econfig->reg_read = meson_efuse_read;
	econfig->reg_write = meson_efuse_write;
	econfig->size = size;
	econfig->priv = fw;

	nvmem = devm_nvmem_register(&pdev->dev, econfig);

	return PTR_ERR_OR_ZERO(nvmem);
}

static struct platform_driver meson_efuse_driver = {
	.probe = meson_efuse_probe,
	.driver = {
		.name = "meson-efuse",
		.of_match_table = meson_efuse_match,
	},
};

module_platform_driver(meson_efuse_driver);

MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
MODULE_DESCRIPTION("Amlogic Meson GX NVMEM driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
5b497af4	1	// SPDX-License-Identifier: GPL-2.0-only
ad855eae	2	/*
9593ad32	3	* Amlogic Meson GX eFuse Driver
ad855eae CC	4	*
	5	* Copyright (c) 2016 Endless Computers, Inc.
	6	* Author: Carlo Caione <carlo@endlessm.com>
ad855eae CC	7	*/
ad855eae CC	8
611fbca1	9	#include <linux/clk.h>
ad855eae CC	10	#include <linux/module.h>
	11	#include <linux/nvmem-provider.h>
	12	#include <linux/of.h>
	13	#include <linux/platform_device.h>
	14
	15	#include <linux/firmware/meson/meson_sm.h>
	16
	17	static int meson_efuse_read(void *context, unsigned int offset,
	18	void *val, size_t bytes)
	19	{
8cde3c21 CC	20	struct meson_sm_firmware *fw = context;
	21
	22	return meson_sm_call_read(fw, (u8 *)val, bytes, SM_EFUSE_READ, offset,
a29a63bd	23	bytes, 0, 0, 0);
ad855eae CC	24	}
ad855eae CC	25
e5507730 JB	26	static int meson_efuse_write(void *context, unsigned int offset,
	27	void *val, size_t bytes)
	28	{
8cde3c21 CC	29	struct meson_sm_firmware *fw = context;
	30
	31	return meson_sm_call_write(fw, (u8 *)val, bytes, SM_EFUSE_WRITE, offset,
e5507730 JB	32	bytes, 0, 0, 0);
	33	}
	34
ad855eae CC	35	static const struct of_device_id meson_efuse_match[] = {
	36	{ .compatible = "amlogic,meson-gxbb-efuse", },
	37	{ /* sentinel */ },
	38	};
	39	MODULE_DEVICE_TABLE(of, meson_efuse_match);
	40
	41	static int meson_efuse_probe(struct platform_device *pdev)
	42	{
401488d1	43	struct device *dev = &pdev->dev;
8cde3c21 CC	44	struct meson_sm_firmware *fw;
8cde3c21 CC	45	struct device_node *sm_np;
ad855eae	46	struct nvmem_device *nvmem;
401488d1	47	struct nvmem_config *econfig;
611fbca1	48	struct clk *clk;
ad855eae	49	unsigned int size;
611fbca1 JB	50	int ret;
611fbca1 JB	51
8cde3c21 CC	52	sm_np = of_parse_phandle(pdev->dev.of_node, "secure-monitor", 0);
	53	if (!sm_np) {
	54	dev_err(&pdev->dev, "no secure-monitor node\n");
	55	return -ENODEV;
	56	}
	57
	58	fw = meson_sm_get(sm_np);
	59	of_node_put(sm_np);
	60	if (!fw)
	61	return -EPROBE_DEFER;
	62
611fbca1 JB	63	clk = devm_clk_get(dev, NULL);
	64	if (IS_ERR(clk)) {
	65	ret = PTR_ERR(clk);
	66	if (ret != -EPROBE_DEFER)
	67	dev_err(dev, "failed to get efuse gate");
	68	return ret;
	69	}
	70
	71	ret = clk_prepare_enable(clk);
	72	if (ret) {
	73	dev_err(dev, "failed to enable gate");
	74	return ret;
	75	}
	76
	77	ret = devm_add_action_or_reset(dev,
	78	(void()(void ))clk_disable_unprepare,
	79	clk);
	80	if (ret) {
	81	dev_err(dev, "failed to add disable callback");
	82	return ret;
	83	}
ad855eae	84
8cde3c21	85	if (meson_sm_call(fw, SM_EFUSE_USER_MAX, &size, 0, 0, 0, 0, 0) < 0) {
8649dbe5	86	dev_err(dev, "failed to get max user");
ad855eae	87	return -EINVAL;
8649dbe5	88	}
ad855eae	89
401488d1 JB	90	econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
	91	if (!econfig)
	92	return -ENOMEM;
	93
	94	econfig->dev = dev;
	95	econfig->name = dev_name(dev);
	96	econfig->stride = 1;
	97	econfig->word_size = 1;
401488d1	98	econfig->reg_read = meson_efuse_read;
e5507730	99	econfig->reg_write = meson_efuse_write;
401488d1	100	econfig->size = size;
8cde3c21	101	econfig->priv = fw;
ad855eae	102
401488d1	103	nvmem = devm_nvmem_register(&pdev->dev, econfig);
ad855eae	104
90696a40	105	return PTR_ERR_OR_ZERO(nvmem);
ad855eae CC	106	}
	107
	108	static struct platform_driver meson_efuse_driver = {
	109	.probe = meson_efuse_probe,
ad855eae CC	110	.driver = {
	111	.name = "meson-efuse",
	112	.of_match_table = meson_efuse_match,
	113	},
	114	};
	115
	116	module_platform_driver(meson_efuse_driver);
	117
	118	MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
9593ad32	119	MODULE_DESCRIPTION("Amlogic Meson GX NVMEM driver");
ad855eae	120	MODULE_LICENSE("GPL v2");