aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-dw-mmio.c
blob: fac399c3022cd4a1045ac09f962309d9e9c63d23 (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
/*
 * Memory-mapped interface driver for DW SPI Core
 *
 * Copyright (c) 2010, Octasic semiconductor.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 */

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/scatterlist.h>

#include "spi-dw.h"

#define DRIVER_NAME "dw_spi_mmio"

struct dw_spi_mmio {
	struct dw_spi  dws;
	struct clk     *clk;
};

static int __devinit dw_spi_mmio_probe(struct platform_device *pdev)
{
	struct dw_spi_mmio *dwsmmio;
	struct dw_spi *dws;
	struct resource *mem, *ioarea;
	int ret;

	dwsmmio = kzalloc(sizeof(struct dw_spi_mmio), GFP_KERNEL);
	if (!dwsmmio) {
		ret = -ENOMEM;
		goto err_end;
	}

	dws = &dwsmmio->dws;

	/* Get basic io resource and map it */
	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem) {
		dev_err(&pdev->dev, "no mem resource?\n");
		ret = -EINVAL;
		goto err_kfree;
	}

	ioarea = request_mem_region(mem->start, resource_size(mem),
			pdev->name);
	if (!ioarea) {
		dev_err(&pdev->dev, "SPI region already claimed\n");
		ret = -EBUSY;
		goto err_kfree;
	}

	dws->regs = ioremap_nocache(mem->start, resource_size(mem));
	if (!dws->regs) {
		dev_err(&pdev->dev, "SPI region already mapped\n");
		ret = -ENOMEM;
		goto err_release_reg;
	}

	dws->irq = platform_get_irq(pdev, 0);
	if (dws->irq < 0) {
		dev_err(&pdev->dev, "no irq resource?\n");
		ret = dws->irq; /* -ENXIO */
		goto err_unmap;
	}

	dwsmmio->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(dwsmmio->clk)) {
		ret = PTR_ERR(dwsmmio->clk);
		goto err_irq;
	}
	clk_enable(dwsmmio->clk);

	dws->parent_dev = &pdev->dev;
	dws->bus_num = 0;
	dws->num_cs = 4;
	dws->max_freq = clk_get_rate(dwsmmio->clk);

	ret = dw_spi_add_host(dws);
	if (ret)
		goto err_clk;

	platform_set_drvdata(pdev, dwsmmio);
	return 0;

err_clk:
	clk_disable(dwsmmio->clk);
	clk_put(dwsmmio->clk);
	dwsmmio->clk = NULL;
err_irq:
	free_irq(dws->irq, dws);
err_unmap:
	iounmap(dws->regs);
err_release_reg:
	release_mem_region(mem->start, resource_size(mem));
err_kfree:
	kfree(dwsmmio);
err_end:
	return ret;
}

static int __devexit dw_spi_mmio_remove(struct platform_device *pdev)
{
	struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
	struct resource *mem;

	platform_set_drvdata(pdev, NULL);

	clk_disable(dwsmmio->clk);
	clk_put(dwsmmio->clk);
	dwsmmio->clk = NULL;

	free_irq(dwsmmio->dws.irq, &dwsmmio->dws);
	dw_spi_remove_host(&dwsmmio->dws);
	iounmap(dwsmmio->dws.regs);
	kfree(dwsmmio);

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	release_mem_region(mem->start, resource_size(mem));
	return 0;
}

static struct platform_driver dw_spi_mmio_driver = {
	.probe		= dw_spi_mmio_probe,
	.remove		= __devexit_p(dw_spi_mmio_remove),
	.driver		= {
		.name	= DRIVER_NAME,
		.owner	= THIS_MODULE,
	},
};
module_platform_driver(dw_spi_mmio_driver);

MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
MODULE_LICENSE("GPL v2");