aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-altera-platform.c
blob: f7a7c14e36790eeeb9247caccfa678d63a25403f (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Altera SPI driver
 *
 * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
 *
 * Based on spi_s3c24xx.c, which is:
 * Copyright (c) 2006 Ben Dooks
 * Copyright (c) 2006 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 */

#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spi/altera.h>
#include <linux/spi/spi.h>
#include <linux/io.h>
#include <linux/of.h>

#define DRV_NAME "spi_altera"

enum altera_spi_type {
	ALTERA_SPI_TYPE_UNKNOWN,
	ALTERA_SPI_TYPE_SUBDEV,
};

static const struct regmap_config spi_altera_config = {
	.reg_bits = 32,
	.reg_stride = 4,
	.val_bits = 32,
	.fast_io = true,
};

static int altera_spi_probe(struct platform_device *pdev)
{
	const struct platform_device_id *platid = platform_get_device_id(pdev);
	struct altera_spi_platform_data *pdata = dev_get_platdata(&pdev->dev);
	enum altera_spi_type type = ALTERA_SPI_TYPE_UNKNOWN;
	struct altera_spi *hw;
	struct spi_master *master;
	int err = -ENODEV;
	u16 i;

	master = spi_alloc_master(&pdev->dev, sizeof(struct altera_spi));
	if (!master)
		return err;

	/* setup the master state. */
	master->bus_num = pdev->id;

	if (pdata) {
		if (pdata->num_chipselect > ALTERA_SPI_MAX_CS) {
			dev_err(&pdev->dev,
				"Invalid number of chipselect: %u\n",
				pdata->num_chipselect);
			err = -EINVAL;
			goto exit;
		}

		master->num_chipselect = pdata->num_chipselect;
		master->mode_bits = pdata->mode_bits;
		master->bits_per_word_mask = pdata->bits_per_word_mask;
	} else {
		master->num_chipselect = 16;
		master->mode_bits = SPI_CS_HIGH;
		master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
	}

	master->dev.of_node = pdev->dev.of_node;

	hw = spi_master_get_devdata(master);
	hw->dev = &pdev->dev;

	if (platid)
		type = platid->driver_data;

	/* find and map our resources */
	if (type == ALTERA_SPI_TYPE_SUBDEV) {
		struct resource *regoff;

		hw->regmap = dev_get_regmap(pdev->dev.parent, NULL);
		if (!hw->regmap) {
			dev_err(&pdev->dev, "get regmap failed\n");
			goto exit;
		}

		regoff = platform_get_resource(pdev, IORESOURCE_REG, 0);
		if (regoff)
			hw->regoff = regoff->start;
	} else {
		void __iomem *res;

		res = devm_platform_ioremap_resource(pdev, 0);
		if (IS_ERR(res)) {
			err = PTR_ERR(res);
			goto exit;
		}

		hw->regmap = devm_regmap_init_mmio(&pdev->dev, res,
						   &spi_altera_config);
		if (IS_ERR(hw->regmap)) {
			dev_err(&pdev->dev, "regmap mmio init failed\n");
			err = PTR_ERR(hw->regmap);
			goto exit;
		}
	}

	altera_spi_init_master(master);

	/* irq is optional */
	hw->irq = platform_get_irq(pdev, 0);
	if (hw->irq >= 0) {
		err = devm_request_irq(&pdev->dev, hw->irq, altera_spi_irq, 0,
				       pdev->name, master);
		if (err)
			goto exit;
	}

	err = devm_spi_register_master(&pdev->dev, master);
	if (err)
		goto exit;

	if (pdata) {
		for (i = 0; i < pdata->num_devices; i++) {
			if (!spi_new_device(master, pdata->devices + i))
				dev_warn(&pdev->dev,
					 "unable to create SPI device: %s\n",
					 pdata->devices[i].modalias);
		}
	}

	dev_info(&pdev->dev, "regoff %u, irq %d\n", hw->regoff, hw->irq);

	return 0;
exit:
	spi_master_put(master);
	return err;
}

#ifdef CONFIG_OF
static const struct of_device_id altera_spi_match[] = {
	{ .compatible = "ALTR,spi-1.0", },
	{ .compatible = "altr,spi-1.0", },
	{},
};
MODULE_DEVICE_TABLE(of, altera_spi_match);
#endif /* CONFIG_OF */

static const struct platform_device_id altera_spi_ids[] = {
	{ DRV_NAME,		ALTERA_SPI_TYPE_UNKNOWN },
	{ "subdev_spi_altera",	ALTERA_SPI_TYPE_SUBDEV },
	{ }
};
MODULE_DEVICE_TABLE(platform, altera_spi_ids);

static struct platform_driver altera_spi_driver = {
	.probe = altera_spi_probe,
	.driver = {
		.name = DRV_NAME,
		.pm = NULL,
		.of_match_table = of_match_ptr(altera_spi_match),
	},
	.id_table	= altera_spi_ids,
};
module_platform_driver(altera_spi_driver);

MODULE_DESCRIPTION("Altera SPI driver");
MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);