summaryrefslogtreecommitdiff
path: root/drivers/nvmem/imx-iim.c
blob: 52ff65e0673f88e8b9ec78cd6b5041e73f166f5d (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
170
171
172
173
/*
 * i.MX IIM driver
 *
 * Copyright (c) 2017 Pengutronix, Michael Grzeschik <m.grzeschik@pengutronix.de>
 *
 * Based on the barebox iim driver,
 * Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>,
 *	Orex Computed Radiography
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * http://www.opensource.org/licenses/gpl-license.html
 * http://www.gnu.org/copyleft/gpl.html
 */

#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/clk.h>

#define IIM_BANK_BASE(n)	(0x800 + 0x400 * (n))

struct imx_iim_drvdata {
	unsigned int nregs;
};

struct iim_priv {
	void __iomem *base;
	struct clk *clk;
	struct nvmem_config nvmem;
};

static int imx_iim_read(void *context, unsigned int offset,
			  void *buf, size_t bytes)
{
	struct iim_priv *iim = context;
	int i, ret;
	u8 *buf8 = buf;

	ret = clk_prepare_enable(iim->clk);
	if (ret)
		return ret;

	for (i = offset; i < offset + bytes; i++) {
		int bank = i >> 5;
		int reg = i & 0x1f;

		*buf8++ = readl(iim->base + IIM_BANK_BASE(bank) + reg * 4);
	}

	clk_disable_unprepare(iim->clk);

	return 0;
}

static struct imx_iim_drvdata imx27_drvdata = {
	.nregs = 2 * 32,
};

static struct imx_iim_drvdata imx25_imx31_imx35_drvdata = {
	.nregs = 3 * 32,
};

static struct imx_iim_drvdata imx51_drvdata = {
	.nregs = 4 * 32,
};

static struct imx_iim_drvdata imx53_drvdata = {
	.nregs = 4 * 32 + 16,
};

static const struct of_device_id imx_iim_dt_ids[] = {
	{
		.compatible = "fsl,imx25-iim",
		.data = &imx25_imx31_imx35_drvdata,
	}, {
		.compatible = "fsl,imx27-iim",
		.data = &imx27_drvdata,
	}, {
		.compatible = "fsl,imx31-iim",
		.data = &imx25_imx31_imx35_drvdata,
	}, {
		.compatible = "fsl,imx35-iim",
		.data = &imx25_imx31_imx35_drvdata,
	}, {
		.compatible = "fsl,imx51-iim",
		.data = &imx51_drvdata,
	}, {
		.compatible = "fsl,imx53-iim",
		.data = &imx53_drvdata,
	}, {
		/* sentinel */
	},
};
MODULE_DEVICE_TABLE(of, imx_iim_dt_ids);

static int imx_iim_probe(struct platform_device *pdev)
{
	const struct of_device_id *of_id;
	struct device *dev = &pdev->dev;
	struct resource *res;
	struct iim_priv *iim;
	struct nvmem_device *nvmem;
	struct nvmem_config *cfg;
	const struct imx_iim_drvdata *drvdata = NULL;

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

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	iim->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(iim->base))
		return PTR_ERR(iim->base);

	of_id = of_match_device(imx_iim_dt_ids, dev);
	if (!of_id)
		return -ENODEV;

	drvdata = of_id->data;

	iim->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(iim->clk))
		return PTR_ERR(iim->clk);

	cfg = &iim->nvmem;

	cfg->name = "imx-iim",
	cfg->read_only = true,
	cfg->word_size = 1,
	cfg->stride = 1,
	cfg->owner = THIS_MODULE,
	cfg->reg_read = imx_iim_read,
	cfg->dev = dev;
	cfg->size = drvdata->nregs;
	cfg->priv = iim;

	nvmem = nvmem_register(cfg);
	if (IS_ERR(nvmem))
		return PTR_ERR(nvmem);

	platform_set_drvdata(pdev, nvmem);

	return 0;
}

static int imx_iim_remove(struct platform_device *pdev)
{
	struct nvmem_device *nvmem = platform_get_drvdata(pdev);

	return nvmem_unregister(nvmem);
}

static struct platform_driver imx_iim_driver = {
	.probe	= imx_iim_probe,
	.remove	= imx_iim_remove,
	.driver = {
		.name	= "imx-iim",
		.of_match_table = imx_iim_dt_ids,
	},
};
module_platform_driver(imx_iim_driver);

MODULE_AUTHOR("Michael Grzeschik <m.grzeschik@pengutronix.de>");
MODULE_DESCRIPTION("i.MX IIM driver");
MODULE_LICENSE("GPL v2");