xref: /openbmc/linux/arch/sh/drivers/dma/dma-sysfs.c (revision a1e58bbd)
1 /*
2  * arch/sh/drivers/dma/dma-sysfs.c
3  *
4  * sysfs interface for SH DMA API
5  *
6  * Copyright (C) 2004 - 2006  Paul Mundt
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file "COPYING" in the main directory of this archive
10  * for more details.
11  */
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/sysdev.h>
15 #include <linux/platform_device.h>
16 #include <linux/module.h>
17 #include <linux/err.h>
18 #include <linux/string.h>
19 #include <asm/dma.h>
20 
21 static struct sysdev_class dma_sysclass = {
22 	.name = "dma",
23 };
24 EXPORT_SYMBOL(dma_sysclass);
25 
26 static ssize_t dma_show_devices(struct sys_device *dev, char *buf)
27 {
28 	ssize_t len = 0;
29 	int i;
30 
31 	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
32 		struct dma_info *info = get_dma_info(i);
33 		struct dma_channel *channel = get_dma_channel(i);
34 
35 		if (unlikely(!info) || !channel)
36 			continue;
37 
38 		len += sprintf(buf + len, "%2d: %14s    %s\n",
39 			       channel->chan, info->name,
40 			       channel->dev_id);
41 	}
42 
43 	return len;
44 }
45 
46 static SYSDEV_ATTR(devices, S_IRUGO, dma_show_devices, NULL);
47 
48 static int __init dma_sysclass_init(void)
49 {
50 	int ret;
51 
52 	ret = sysdev_class_register(&dma_sysclass);
53 	if (unlikely(ret))
54 		return ret;
55 
56 	return sysfs_create_file(&dma_sysclass.kset.kobj, &attr_devices.attr);
57 }
58 postcore_initcall(dma_sysclass_init);
59 
60 static ssize_t dma_show_dev_id(struct sys_device *dev, char *buf)
61 {
62 	struct dma_channel *channel = to_dma_channel(dev);
63 	return sprintf(buf, "%s\n", channel->dev_id);
64 }
65 
66 static ssize_t dma_store_dev_id(struct sys_device *dev,
67 				const char *buf, size_t count)
68 {
69 	struct dma_channel *channel = to_dma_channel(dev);
70 	strcpy(channel->dev_id, buf);
71 	return count;
72 }
73 
74 static SYSDEV_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
75 
76 static ssize_t dma_store_config(struct sys_device *dev,
77 				const char *buf, size_t count)
78 {
79 	struct dma_channel *channel = to_dma_channel(dev);
80 	unsigned long config;
81 
82 	config = simple_strtoul(buf, NULL, 0);
83 	dma_configure_channel(channel->vchan, config);
84 
85 	return count;
86 }
87 
88 static SYSDEV_ATTR(config, S_IWUSR, NULL, dma_store_config);
89 
90 static ssize_t dma_show_mode(struct sys_device *dev, char *buf)
91 {
92 	struct dma_channel *channel = to_dma_channel(dev);
93 	return sprintf(buf, "0x%08x\n", channel->mode);
94 }
95 
96 static ssize_t dma_store_mode(struct sys_device *dev,
97 			      const char *buf, size_t count)
98 {
99 	struct dma_channel *channel = to_dma_channel(dev);
100 	channel->mode = simple_strtoul(buf, NULL, 0);
101 	return count;
102 }
103 
104 static SYSDEV_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
105 
106 #define dma_ro_attr(field, fmt)						\
107 static ssize_t dma_show_##field(struct sys_device *dev, char *buf)	\
108 {									\
109 	struct dma_channel *channel = to_dma_channel(dev);		\
110 	return sprintf(buf, fmt, channel->field);			\
111 }									\
112 static SYSDEV_ATTR(field, S_IRUGO, dma_show_##field, NULL);
113 
114 dma_ro_attr(count, "0x%08x\n");
115 dma_ro_attr(flags, "0x%08lx\n");
116 
117 int dma_create_sysfs_files(struct dma_channel *chan, struct dma_info *info)
118 {
119 	struct sys_device *dev = &chan->dev;
120 	char name[16];
121 	int ret;
122 
123 	dev->id  = chan->vchan;
124 	dev->cls = &dma_sysclass;
125 
126 	ret = sysdev_register(dev);
127 	if (ret)
128 		return ret;
129 
130 	ret |= sysdev_create_file(dev, &attr_dev_id);
131 	ret |= sysdev_create_file(dev, &attr_count);
132 	ret |= sysdev_create_file(dev, &attr_mode);
133 	ret |= sysdev_create_file(dev, &attr_flags);
134 	ret |= sysdev_create_file(dev, &attr_config);
135 
136 	if (unlikely(ret)) {
137 		dev_err(&info->pdev->dev, "Failed creating attrs\n");
138 		return ret;
139 	}
140 
141 	snprintf(name, sizeof(name), "dma%d", chan->chan);
142 	return sysfs_create_link(&info->pdev->dev.kobj, &dev->kobj, name);
143 }
144 
145 void dma_remove_sysfs_files(struct dma_channel *chan, struct dma_info *info)
146 {
147 	struct sys_device *dev = &chan->dev;
148 	char name[16];
149 
150 	sysdev_remove_file(dev, &attr_dev_id);
151 	sysdev_remove_file(dev, &attr_count);
152 	sysdev_remove_file(dev, &attr_mode);
153 	sysdev_remove_file(dev, &attr_flags);
154 	sysdev_remove_file(dev, &attr_config);
155 
156 	snprintf(name, sizeof(name), "dma%d", chan->chan);
157 	sysfs_remove_link(&info->pdev->dev.kobj, name);
158 
159 	sysdev_unregister(dev);
160 }
161