1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * arch/sh/drivers/dma/dma-sysfs.c
4 *
5 * sysfs interface for SH DMA API
6 *
7 * Copyright (C) 2004 - 2006 Paul Mundt
8 */
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/stat.h>
12 #include <linux/device.h>
13 #include <linux/platform_device.h>
14 #include <linux/err.h>
15 #include <linux/string.h>
16 #include <asm/dma.h>
17
18 static const struct bus_type dma_subsys = {
19 .name = "dma",
20 .dev_name = "dma",
21 };
22
23 static ssize_t dma_show_devices(struct device *dev,
24 struct device_attribute *attr, char *buf)
25 {
26 ssize_t len = 0;
27 int i;
28
29 for (i = 0; i < 16; i++) {
30 struct dma_info *info = get_dma_info(i);
31 struct dma_channel *channel = get_dma_channel(i);
32
33 if (unlikely(!info) || !channel)
34 continue;
35
36 len += sprintf(buf + len, "%2d: %14s %s\n",
37 channel->chan, info->name,
38 channel->dev_id);
39 }
40
41 return len;
42 }
43
44 static DEVICE_ATTR(devices, S_IRUGO, dma_show_devices, NULL);
45
46 static int __init dma_subsys_init(void)
47 {
48 struct device *dev_root;
49 int ret;
50
51 ret = subsys_system_register(&dma_subsys, NULL);
52 if (unlikely(ret))
53 return ret;
54
55 dev_root = bus_get_dev_root(&dma_subsys);
56 if (dev_root) {
57 ret = device_create_file(dev_root, &dev_attr_devices);
58 put_device(dev_root);
59 }
60 return ret;
61 }
62 postcore_initcall(dma_subsys_init);
63
64 static ssize_t dma_show_dev_id(struct device *dev,
65 struct device_attribute *attr, char *buf)
66 {
67 struct dma_channel *channel = to_dma_channel(dev);
68 return sprintf(buf, "%s\n", channel->dev_id);
69 }
70
71 static ssize_t dma_store_dev_id(struct device *dev,
72 struct device_attribute *attr,
73 const char *buf, size_t count)
74 {
75 struct dma_channel *channel = to_dma_channel(dev);
76 strcpy(channel->dev_id, buf);
77 return count;
78 }
79
80 static DEVICE_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
81
82 static ssize_t dma_store_config(struct device *dev,
83 struct device_attribute *attr,
84 const char *buf, size_t count)
85 {
86 struct dma_channel *channel = to_dma_channel(dev);
87 unsigned long config;
88
89 config = simple_strtoul(buf, NULL, 0);
90 dma_configure_channel(channel->vchan, config);
91
92 return count;
93 }
94
95 static DEVICE_ATTR(config, S_IWUSR, NULL, dma_store_config);
96
97 static ssize_t dma_show_mode(struct device *dev,
98 struct device_attribute *attr, char *buf)
99 {
100 struct dma_channel *channel = to_dma_channel(dev);
101 return sprintf(buf, "0x%08x\n", channel->mode);
102 }
103
104 static ssize_t dma_store_mode(struct device *dev,
105 struct device_attribute *attr,
106 const char *buf, size_t count)
107 {
108 struct dma_channel *channel = to_dma_channel(dev);
109 channel->mode = simple_strtoul(buf, NULL, 0);
110 return count;
111 }
112
113 static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
114
115 #define dma_ro_attr(field, fmt) \
116 static ssize_t dma_show_##field(struct device *dev, \
117 struct device_attribute *attr, char *buf)\
118 { \
119 struct dma_channel *channel = to_dma_channel(dev); \
120 return sprintf(buf, fmt, channel->field); \
121 } \
122 static DEVICE_ATTR(field, S_IRUGO, dma_show_##field, NULL);
123
124 dma_ro_attr(count, "0x%08x\n");
125 dma_ro_attr(flags, "0x%08lx\n");
126
127 int dma_create_sysfs_files(struct dma_channel *chan, struct dma_info *info)
128 {
129 struct device *dev = &chan->dev;
130 char name[16];
131 int ret;
132
133 dev->id = chan->vchan;
134 dev->bus = &dma_subsys;
135
136 ret = device_register(dev);
137 if (ret)
138 return ret;
139
140 ret |= device_create_file(dev, &dev_attr_dev_id);
141 ret |= device_create_file(dev, &dev_attr_count);
142 ret |= device_create_file(dev, &dev_attr_mode);
143 ret |= device_create_file(dev, &dev_attr_flags);
144 ret |= device_create_file(dev, &dev_attr_config);
145
146 if (unlikely(ret)) {
147 dev_err(&info->pdev->dev, "Failed creating attrs\n");
148 return ret;
149 }
150
151 snprintf(name, sizeof(name), "dma%d", chan->chan);
152 return sysfs_create_link(&info->pdev->dev.kobj, &dev->kobj, name);
153 }
154
155 void dma_remove_sysfs_files(struct dma_channel *chan, struct dma_info *info)
156 {
157 struct device *dev = &chan->dev;
158 char name[16];
159
160 device_remove_file(dev, &dev_attr_dev_id);
161 device_remove_file(dev, &dev_attr_count);
162 device_remove_file(dev, &dev_attr_mode);
163 device_remove_file(dev, &dev_attr_flags);
164 device_remove_file(dev, &dev_attr_config);
165
166 snprintf(name, sizeof(name), "dma%d", chan->chan);
167 sysfs_remove_link(&info->pdev->dev.kobj, name);
168
169 device_unregister(dev);
170 }
171
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