summaryrefslogtreecommitdiff
path: root/drivers/memory/pl353-smc.c
blob: d39ee7d06665bdb8485f505ff8fe19f922e52484 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
// SPDX-License-Identifier: GPL-2.0
/*
 * ARM PL353 SMC driver
 *
 * Copyright (C) 2012 - 2018 Xilinx, Inc
 * Author: Punnaiah Choudary Kalluri <punnaiah@xilinx.com>
 * Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
 */

#include <linux/clk.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/amba/bus.h>

/**
 * struct pl353_smc_data - Private smc driver structure
 * @memclk:		Pointer to the peripheral clock
 * @aclk:		Pointer to the AXI peripheral clock
 */
struct pl353_smc_data {
	struct clk		*memclk;
	struct clk		*aclk;
};

static int __maybe_unused pl353_smc_suspend(struct device *dev)
{
	struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);

	clk_disable(pl353_smc->memclk);
	clk_disable(pl353_smc->aclk);

	return 0;
}

static int __maybe_unused pl353_smc_resume(struct device *dev)
{
	struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
	int ret;

	ret = clk_enable(pl353_smc->aclk);
	if (ret) {
		dev_err(dev, "Cannot enable axi domain clock.\n");
		return ret;
	}

	ret = clk_enable(pl353_smc->memclk);
	if (ret) {
		dev_err(dev, "Cannot enable memory clock.\n");
		clk_disable(pl353_smc->aclk);
		return ret;
	}

	return ret;
}

static SIMPLE_DEV_PM_OPS(pl353_smc_dev_pm_ops, pl353_smc_suspend,
			 pl353_smc_resume);

static const struct of_device_id pl353_smc_supported_children[] = {
	{
		.compatible = "cfi-flash"
	},
	{
		.compatible = "arm,pl353-nand-r2p1",
	},
	{}
};

static int pl353_smc_probe(struct amba_device *adev, const struct amba_id *id)
{
	struct device_node *of_node = adev->dev.of_node;
	const struct of_device_id *match = NULL;
	struct pl353_smc_data *pl353_smc;
	struct device_node *child;
	int err;

	pl353_smc = devm_kzalloc(&adev->dev, sizeof(*pl353_smc), GFP_KERNEL);
	if (!pl353_smc)
		return -ENOMEM;

	pl353_smc->aclk = devm_clk_get(&adev->dev, "apb_pclk");
	if (IS_ERR(pl353_smc->aclk)) {
		dev_err(&adev->dev, "aclk clock not found.\n");
		return PTR_ERR(pl353_smc->aclk);
	}

	pl353_smc->memclk = devm_clk_get(&adev->dev, "memclk");
	if (IS_ERR(pl353_smc->memclk)) {
		dev_err(&adev->dev, "memclk clock not found.\n");
		return PTR_ERR(pl353_smc->memclk);
	}

	err = clk_prepare_enable(pl353_smc->aclk);
	if (err) {
		dev_err(&adev->dev, "Unable to enable AXI clock.\n");
		return err;
	}

	err = clk_prepare_enable(pl353_smc->memclk);
	if (err) {
		dev_err(&adev->dev, "Unable to enable memory clock.\n");
		goto disable_axi_clk;
	}

	amba_set_drvdata(adev, pl353_smc);

	/* Find compatible children. Only a single child is supported */
	for_each_available_child_of_node(of_node, child) {
		match = of_match_node(pl353_smc_supported_children, child);
		if (!match) {
			dev_warn(&adev->dev, "unsupported child node\n");
			continue;
		}
		break;
	}
	if (!match) {
		err = -ENODEV;
		dev_err(&adev->dev, "no matching children\n");
		goto disable_mem_clk;
	}

	of_platform_device_create(child, NULL, &adev->dev);
	of_node_put(child);

	return 0;

disable_mem_clk:
	clk_disable_unprepare(pl353_smc->memclk);
disable_axi_clk:
	clk_disable_unprepare(pl353_smc->aclk);

	return err;
}

static void pl353_smc_remove(struct amba_device *adev)
{
	struct pl353_smc_data *pl353_smc = amba_get_drvdata(adev);

	clk_disable_unprepare(pl353_smc->memclk);
	clk_disable_unprepare(pl353_smc->aclk);
}

static const struct amba_id pl353_ids[] = {
	{
		.id = 0x00041353,
		.mask = 0x000fffff,
	},
	{ 0, 0 },
};
MODULE_DEVICE_TABLE(amba, pl353_ids);

static struct amba_driver pl353_smc_driver = {
	.drv = {
		.owner = THIS_MODULE,
		.name = "pl353-smc",
		.pm = &pl353_smc_dev_pm_ops,
	},
	.id_table = pl353_ids,
	.probe = pl353_smc_probe,
	.remove = pl353_smc_remove,
};

module_amba_driver(pl353_smc_driver);

MODULE_AUTHOR("Xilinx, Inc.");
MODULE_DESCRIPTION("ARM PL353 SMC Driver");
MODULE_LICENSE("GPL");