82 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * Copyright (C) 2020 Sean Anderson
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|  */
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| 
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| #include <common.h>
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| #include <dm.h>
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| #include <regmap.h>
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| #include <reset.h>
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| #include <reset-uclass.h>
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| #include <syscon.h>
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| #include <linux/bitops.h>
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| #include <linux/err.h>
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| 
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| struct syscon_reset_priv {
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| 	struct regmap *regmap;
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| 	uint offset;
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| 	uint mask;
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| 	bool assert_high;
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| };
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| 
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| static int syscon_reset_request(struct reset_ctl *rst)
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| {
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| 	struct syscon_reset_priv *priv = dev_get_priv(rst->dev);
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| 
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| 	if (BIT(rst->id) & priv->mask)
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| 		return 0;
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| 	else
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| 		return -EINVAL;
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| }
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| 
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| static int syscon_reset_assert(struct reset_ctl *rst)
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| {
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| 	struct syscon_reset_priv *priv = dev_get_priv(rst->dev);
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| 
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| 	return regmap_update_bits(priv->regmap, priv->offset, BIT(rst->id),
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| 				  priv->assert_high ? BIT(rst->id) : 0);
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| }
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| 
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| static int syscon_reset_deassert(struct reset_ctl *rst)
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| {
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| 	struct syscon_reset_priv *priv = dev_get_priv(rst->dev);
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| 
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| 	return regmap_update_bits(priv->regmap, priv->offset, BIT(rst->id),
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| 				  priv->assert_high ? 0 : BIT(rst->id));
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| }
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| 
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| static const struct reset_ops syscon_reset_ops = {
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| 	.request = syscon_reset_request,
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| 	.rst_assert = syscon_reset_assert,
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| 	.rst_deassert = syscon_reset_deassert,
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| };
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| 
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| int syscon_reset_probe(struct udevice *dev)
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| {
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| 	struct syscon_reset_priv *priv = dev_get_priv(dev);
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| 
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| 	priv->regmap = syscon_regmap_lookup_by_phandle(dev, "regmap");
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| 	if (IS_ERR(priv->regmap))
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| 		return -ENODEV;
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| 
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| 	priv->offset = dev_read_u32_default(dev, "offset", 0);
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| 	priv->mask = dev_read_u32_default(dev, "mask", 0);
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| 	priv->assert_high = dev_read_u32_default(dev, "assert-high", true);
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| 
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| 	return 0;
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| }
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| 
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| static const struct udevice_id syscon_reset_ids[] = {
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| 	{ .compatible = "syscon-reset" },
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| 	{ },
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| };
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| 
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| U_BOOT_DRIVER(syscon_reset) = {
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| 	.name = "syscon_reset",
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| 	.id = UCLASS_RESET,
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| 	.of_match = syscon_reset_ids,
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| 	.probe = syscon_reset_probe,
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| 	.priv_auto_alloc_size = sizeof(struct syscon_reset_priv),
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| 	.ops = &syscon_reset_ops,
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| };
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