summaryrefslogtreecommitdiffstats
path: root/drivers/bus/imx-weim.c
blob: 4bd361d6427032e80434ed1889ef237d42520850 (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
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
/*
 * EIM driver for Freescale's i.MX chips
 *
 * Copyright (C) 2013 Freescale Semiconductor, Inc.
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/of_device.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
#include <linux/regmap.h>

struct imx_weim_devtype {
	unsigned int	cs_count;
	unsigned int	cs_regs_count;
	unsigned int	cs_stride;
};

static const struct imx_weim_devtype imx1_weim_devtype = {
	.cs_count	= 6,
	.cs_regs_count	= 2,
	.cs_stride	= 0x08,
};

static const struct imx_weim_devtype imx27_weim_devtype = {
	.cs_count	= 6,
	.cs_regs_count	= 3,
	.cs_stride	= 0x10,
};

static const struct imx_weim_devtype imx50_weim_devtype = {
	.cs_count	= 4,
	.cs_regs_count	= 6,
	.cs_stride	= 0x18,
};

static const struct imx_weim_devtype imx51_weim_devtype = {
	.cs_count	= 6,
	.cs_regs_count	= 6,
	.cs_stride	= 0x18,
};

static const struct of_device_id weim_id_table[] = {
	/* i.MX1/21 */
	{ .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, },
	/* i.MX25/27/31/35 */
	{ .compatible = "fsl,imx27-weim", .data = &imx27_weim_devtype, },
	/* i.MX50/53/6Q */
	{ .compatible = "fsl,imx50-weim", .data = &imx50_weim_devtype, },
	{ .compatible = "fsl,imx6q-weim", .data = &imx50_weim_devtype, },
	/* i.MX51 */
	{ .compatible = "fsl,imx51-weim", .data = &imx51_weim_devtype, },
	{ }
};
MODULE_DEVICE_TABLE(of, weim_id_table);

static int __init imx_weim_gpr_setup(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct property *prop;
	const __be32 *p;
	struct regmap *gpr;
	u32 gprvals[4] = {
		05,	/* CS0(128M) CS1(0M)  CS2(0M)  CS3(0M)  */
		033,	/* CS0(64M)  CS1(64M) CS2(0M)  CS3(0M)  */
		0113,	/* CS0(64M)  CS1(32M) CS2(32M) CS3(0M)  */
		01111,	/* CS0(32M)  CS1(32M) CS2(32M) CS3(32M) */
	};
	u32 gprval = 0;
	u32 val;
	int cs = 0;
	int i = 0;

	gpr = syscon_regmap_lookup_by_phandle(np, "fsl,weim-cs-gpr");
	if (IS_ERR(gpr)) {
		dev_dbg(&pdev->dev, "failed to find weim-cs-gpr\n");
		return 0;
	}

	of_property_for_each_u32(np, "ranges", prop, p, val) {
		if (i % 4 == 0) {
			cs = val;
		} else if (i % 4 == 3 && val) {
			val = (val / SZ_32M) | 1;
			gprval |= val << cs * 3;
		}
		i++;
	}

	if (i == 0 || i % 4)
		goto err;

	for (i = 0; i < ARRAY_SIZE(gprvals); i++) {
		if (gprval == gprvals[i]) {
			/* Found it. Set up IOMUXC_GPR1[11:0] with it. */
			regmap_update_bits(gpr, IOMUXC_GPR1, 0xfff, gprval);
			return 0;
		}
	}

err:
	dev_err(&pdev->dev, "Invalid 'ranges' configuration\n");
	return -EINVAL;
}

/* Parse and set the timing for this device. */
static int __init weim_timing_setup(struct device_node *np, void __iomem *base,
				    const struct imx_weim_devtype *devtype)
{
	u32 cs_idx, value[devtype->cs_regs_count];
	int i, ret;

	/* get the CS index from this child node's "reg" property. */
	ret = of_property_read_u32(np, "reg", &cs_idx);
	if (ret)
		return ret;

	if (cs_idx >= devtype->cs_count)
		return -EINVAL;

	ret = of_property_read_u32_array(np, "fsl,weim-cs-timing",
					 value, devtype->cs_regs_count);
	if (ret)
		return ret;

	/* set the timing for WEIM */
	for (i = 0; i < devtype->cs_regs_count; i++)
		writel(value[i], base + cs_idx * devtype->cs_stride + i * 4);

	return 0;
}

static int __init weim_parse_dt(struct platform_device *pdev,
				void __iomem *base)
{
	const struct of_device_id *of_id = of_match_device(weim_id_table,
							   &pdev->dev);
	const struct imx_weim_devtype *devtype = of_id->data;
	struct device_node *child;
	int ret, have_child = 0;

	if (devtype == &imx50_weim_devtype) {
		ret = imx_weim_gpr_setup(pdev);
		if (ret)
			return ret;
	}

	for_each_available_child_of_node(pdev->dev.of_node, child) {
		if (!child->name)
			continue;

		ret = weim_timing_setup(child, base, devtype);
		if (ret)
			dev_warn(&pdev->dev, "%s set timing failed.\n",
				child->full_name);
		else
			have_child = 1;
	}

	if (have_child)
		ret = of_platform_default_populate(pdev->dev.of_node,
						   NULL, &pdev->dev);
	if (ret)
		dev_err(&pdev->dev, "%s fail to create devices.\n",
			pdev->dev.of_node->full_name);
	return ret;
}

static int __init weim_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct clk *clk;
	void __iomem *base;
	int ret;

	/* get the resource */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(base))
		return PTR_ERR(base);

	/* get the clock */
	clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(clk))
		return PTR_ERR(clk);

	ret = clk_prepare_enable(clk);
	if (ret)
		return ret;

	/* parse the device node */
	ret = weim_parse_dt(pdev, base);
	if (ret)
		clk_disable_unprepare(clk);
	else
		dev_info(&pdev->dev, "Driver registered.\n");

	return ret;
}

static struct platform_driver weim_driver = {
	.driver = {
		.name		= "imx-weim",
		.of_match_table	= weim_id_table,
	},
};
module_platform_driver_probe(weim_driver, weim_probe);

MODULE_AUTHOR("Freescale Semiconductor Inc.");
MODULE_DESCRIPTION("i.MX EIM Controller Driver");
MODULE_LICENSE("GPL");