xref: /openbmc/linux/arch/sh/drivers/dma/dma-sysfs.c (revision 9f380456)
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/stat.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
17 #include <linux/err.h>
18 #include <linux/string.h>
19 #include <asm/dma.h>
20 
21 static struct bus_type dma_subsys = {
22 	.name = "dma",
23 	.dev_name = "dma",
24 };
25 
26 static ssize_t dma_show_devices(struct device *dev,
27 				struct device_attribute *attr, char *buf)
28 {
29 	ssize_t len = 0;
30 	int i;
31 
32 	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
33 		struct dma_info *info = get_dma_info(i);
34 		struct dma_channel *channel = get_dma_channel(i);
35 
36 		if (unlikely(!info) || !channel)
37 			continue;
38 
39 		len += sprintf(buf + len, "%2d: %14s    %s\n",
40 			       channel->chan, info->name,
41 			       channel->dev_id);
42 	}
43 
44 	return len;
45 }
46 
47 static DEVICE_ATTR(devices, S_IRUGO, dma_show_devices, NULL);
48 
49 static int __init dma_subsys_init(void)
50 {
51 	int ret;
52 
53 	ret = subsys_system_register(&dma_subsys, NULL);
54 	if (unlikely(ret))
55 		return ret;
56 
57 	return device_create_file(dma_subsys.dev_root, &dev_attr_devices);
58 }
59 postcore_initcall(dma_subsys_init);
60 
61 static ssize_t dma_show_dev_id(struct device *dev,
62 				struct device_attribute *attr, char *buf)
63 {
64 	struct dma_channel *channel = to_dma_channel(dev);
65 	return sprintf(buf, "%s\n", channel->dev_id);
66 }
67 
68 static ssize_t dma_store_dev_id(struct device *dev,
69 				struct device_attribute *attr,
70 				const char *buf, size_t count)
71 {
72 	struct dma_channel *channel = to_dma_channel(dev);
73 	strcpy(channel->dev_id, buf);
74 	return count;
75 }
76 
77 static DEVICE_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
78 
79 static ssize_t dma_store_config(struct device *dev,
80 				struct device_attribute *attr,
81 				const char *buf, size_t count)
82 {
83 	struct dma_channel *channel = to_dma_channel(dev);
84 	unsigned long config;
85 
86 	config = simple_strtoul(buf, NULL, 0);
87 	dma_configure_channel(channel->vchan, config);
88 
89 	return count;
90 }
91 
92 static DEVICE_ATTR(config, S_IWUSR, NULL, dma_store_config);
93 
94 static ssize_t dma_show_mode(struct device *dev,
95 				struct device_attribute *attr, char *buf)
96 {
97 	struct dma_channel *channel = to_dma_channel(dev);
98 	return sprintf(buf, "0x%08x\n", channel->mode);
99 }
100 
101 static ssize_t dma_store_mode(struct device *dev,
102 			      struct device_attribute *attr,
103 			      const char *buf, size_t count)
104 {
105 	struct dma_channel *channel = to_dma_channel(dev);
106 	channel->mode = simple_strtoul(buf, NULL, 0);
107 	return count;
108 }
109 
110 static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
111 
112 #define dma_ro_attr(field, fmt)						\
113 static ssize_t dma_show_##field(struct device *dev,		\
114 				struct device_attribute *attr, char *buf)\
115 {									\
116 	struct dma_channel *channel = to_dma_channel(dev);		\
117 	return sprintf(buf, fmt, channel->field);			\
118 }									\
119 static DEVICE_ATTR(field, S_IRUGO, dma_show_##field, NULL);
120 
121 dma_ro_attr(count, "0x%08x\n");
122 dma_ro_attr(flags, "0x%08lx\n");
123 
124 int dma_create_sysfs_files(struct dma_channel *chan, struct dma_info *info)
125 {
126 	struct device *dev = &chan->dev;
127 	char name[16];
128 	int ret;
129 
130 	dev->id  = chan->vchan;
131 	dev->bus = &dma_subsys;
132 
133 	ret = device_register(dev);
134 	if (ret)
135 		return ret;
136 
137 	ret |= device_create_file(dev, &dev_attr_dev_id);
138 	ret |= device_create_file(dev, &dev_attr_count);
139 	ret |= device_create_file(dev, &dev_attr_mode);
140 	ret |= device_create_file(dev, &dev_attr_flags);
141 	ret |= device_create_file(dev, &dev_attr_config);
142 
143 	if (unlikely(ret)) {
144 		dev_err(&info->pdev->dev, "Failed creating attrs\n");
145 		return ret;
146 	}
147 
148 	snprintf(name, sizeof(name), "dma%d", chan->chan);
149 	return sysfs_create_link(&info->pdev->dev.kobj, &dev->kobj, name);
150 }
151 
152 void dma_remove_sysfs_files(struct dma_channel *chan, struct dma_info *info)
153 {
154 	struct device *dev = &chan->dev;
155 	char name[16];
156 
157 	device_remove_file(dev, &dev_attr_dev_id);
158 	device_remove_file(dev, &dev_attr_count);
159 	device_remove_file(dev, &dev_attr_mode);
160 	device_remove_file(dev, &dev_attr_flags);
161 	device_remove_file(dev, &dev_attr_config);
162 
163 	snprintf(name, sizeof(name), "dma%d", chan->chan);
164 	sysfs_remove_link(&info->pdev->dev.kobj, name);
165 
166 	device_unregister(dev);
167 }
168