tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Xilinx SPI OF device driver
3 *
4 * Copyright (c) 2009 Intel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20/* Supports:
21 * Xilinx SPI devices as OF devices
22 *
23 * Inspired by xilinx_spi.c, 2002-2007 (c) MontaVista Software, Inc.
24 */
25
26#include <linux/module.h>
27#include <linux/init.h>
28#include <linux/interrupt.h>
29#include <linux/io.h>
30
31#include <linux/of_platform.h>
32#include <linux/of_device.h>
33#include <linux/of_spi.h>
34
35#include <linux/spi/xilinx_spi.h>
36#include "xilinx_spi.h"
37
38
39static int __devinit xilinx_spi_of_probe(struct of_device *ofdev,
40 const struct of_device_id *match)
41{
42 struct spi_master *master;
43 struct xspi_platform_data *pdata;
44 struct resource r_mem;
45 struct resource r_irq;
46 int rc = 0;
47 const u32 *prop;
48 int len;
49
50 rc = of_address_to_resource(ofdev->node, 0, &r_mem);
51 if (rc) {
52 dev_warn(&ofdev->dev, "invalid address\n");
53 return rc;
54 }
55
56 rc = of_irq_to_resource(ofdev->node, 0, &r_irq);
57 if (rc == NO_IRQ) {
58 dev_warn(&ofdev->dev, "no IRQ found\n");
59 return -ENODEV;
60 }
61
62 ofdev->dev.platform_data =
63 kzalloc(sizeof(struct xspi_platform_data), GFP_KERNEL);
64 pdata = ofdev->dev.platform_data;
65 if (!pdata)
66 return -ENOMEM;
67
68 /* number of slave select bits is required */
69 prop = of_get_property(ofdev->node, "xlnx,num-ss-bits", &len);
70 if (!prop || len < sizeof(*prop)) {
71 dev_warn(&ofdev->dev, "no 'xlnx,num-ss-bits' property\n");
72 return -EINVAL;
73 }
74 pdata->num_chipselect = *prop;
75 pdata->bits_per_word = 8;
76 master = xilinx_spi_init(&ofdev->dev, &r_mem, r_irq.start, -1);
77 if (!master)
78 return -ENODEV;
79
80 dev_set_drvdata(&ofdev->dev, master);
81
82 /* Add any subnodes on the SPI bus */
83 of_register_spi_devices(master, ofdev->node);
84
85 return 0;
86}
87
88static int __devexit xilinx_spi_remove(struct of_device *ofdev)
89{
90 xilinx_spi_deinit(dev_get_drvdata(&ofdev->dev));
91 dev_set_drvdata(&ofdev->dev, 0);
92 kfree(ofdev->dev.platform_data);
93 ofdev->dev.platform_data = NULL;
94 return 0;
95}
96
97static int __exit xilinx_spi_of_remove(struct of_device *op)
98{
99 return xilinx_spi_remove(op);
100}
101
102static const struct of_device_id xilinx_spi_of_match[] = {
103 { .compatible = "xlnx,xps-spi-2.00.a", },
104 { .compatible = "xlnx,xps-spi-2.00.b", },
105 {}
106};
107
108MODULE_DEVICE_TABLE(of, xilinx_spi_of_match);
109
110static struct of_platform_driver xilinx_spi_of_driver = {
111 .match_table = xilinx_spi_of_match,
112 .probe = xilinx_spi_of_probe,
113 .remove = __exit_p(xilinx_spi_of_remove),
114 .driver = {
115 .name = "xilinx-xps-spi",
116 .owner = THIS_MODULE,
117 },
118};
119
120static int __init xilinx_spi_of_init(void)
121{
122 return of_register_platform_driver(&xilinx_spi_of_driver);
123}
124module_init(xilinx_spi_of_init);
125
126static void __exit xilinx_spi_of_exit(void)
127{
128 of_unregister_platform_driver(&xilinx_spi_of_driver);
129}
130module_exit(xilinx_spi_of_exit);
131
132MODULE_AUTHOR("Mocean Laboratories <info@mocean-labs.com>");
133MODULE_DESCRIPTION("Xilinx SPI platform driver");
134MODULE_LICENSE("GPL v2");