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 struct bus_type dma_subsys = {
19 .name = "dma",
20 .dev_name = "dma",
21 };
22
dma_show_devices(struct device * dev,struct device_attribute * attr,char * buf)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
dma_subsys_init(void)46 static int __init dma_subsys_init(void)
47 {
48 int ret;
49
50 ret = subsys_system_register(&dma_subsys, NULL);
51 if (unlikely(ret))
52 return ret;
53
54 return device_create_file(dma_subsys.dev_root, &dev_attr_devices);
55 }
56 postcore_initcall(dma_subsys_init);
57
dma_show_dev_id(struct device * dev,struct device_attribute * attr,char * buf)58 static ssize_t dma_show_dev_id(struct device *dev,
59 struct device_attribute *attr, char *buf)
60 {
61 struct dma_channel *channel = to_dma_channel(dev);
62 return sprintf(buf, "%s\n", channel->dev_id);
63 }
64
dma_store_dev_id(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)65 static ssize_t dma_store_dev_id(struct device *dev,
66 struct device_attribute *attr,
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 DEVICE_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
75
dma_store_config(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)76 static ssize_t dma_store_config(struct device *dev,
77 struct device_attribute *attr,
78 const char *buf, size_t count)
79 {
80 struct dma_channel *channel = to_dma_channel(dev);
81 unsigned long config;
82
83 config = simple_strtoul(buf, NULL, 0);
84 dma_configure_channel(channel->vchan, config);
85
86 return count;
87 }
88
89 static DEVICE_ATTR(config, S_IWUSR, NULL, dma_store_config);
90
dma_show_mode(struct device * dev,struct device_attribute * attr,char * buf)91 static ssize_t dma_show_mode(struct device *dev,
92 struct device_attribute *attr, char *buf)
93 {
94 struct dma_channel *channel = to_dma_channel(dev);
95 return sprintf(buf, "0x%08x\n", channel->mode);
96 }
97
dma_store_mode(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)98 static ssize_t dma_store_mode(struct device *dev,
99 struct device_attribute *attr,
100 const char *buf, size_t count)
101 {
102 struct dma_channel *channel = to_dma_channel(dev);
103 channel->mode = simple_strtoul(buf, NULL, 0);
104 return count;
105 }
106
107 static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
108
109 #define dma_ro_attr(field, fmt) \
110 static ssize_t dma_show_##field(struct device *dev, \
111 struct device_attribute *attr, char *buf)\
112 { \
113 struct dma_channel *channel = to_dma_channel(dev); \
114 return sprintf(buf, fmt, channel->field); \
115 } \
116 static DEVICE_ATTR(field, S_IRUGO, dma_show_##field, NULL);
117
118 dma_ro_attr(count, "0x%08x\n");
119 dma_ro_attr(flags, "0x%08lx\n");
120
dma_create_sysfs_files(struct dma_channel * chan,struct dma_info * info)121 int dma_create_sysfs_files(struct dma_channel *chan, struct dma_info *info)
122 {
123 struct device *dev = &chan->dev;
124 char name[16];
125 int ret;
126
127 dev->id = chan->vchan;
128 dev->bus = &dma_subsys;
129
130 ret = device_register(dev);
131 if (ret)
132 return ret;
133
134 ret |= device_create_file(dev, &dev_attr_dev_id);
135 ret |= device_create_file(dev, &dev_attr_count);
136 ret |= device_create_file(dev, &dev_attr_mode);
137 ret |= device_create_file(dev, &dev_attr_flags);
138 ret |= device_create_file(dev, &dev_attr_config);
139
140 if (unlikely(ret)) {
141 dev_err(&info->pdev->dev, "Failed creating attrs\n");
142 return ret;
143 }
144
145 snprintf(name, sizeof(name), "dma%d", chan->chan);
146 return sysfs_create_link(&info->pdev->dev.kobj, &dev->kobj, name);
147 }
148
dma_remove_sysfs_files(struct dma_channel * chan,struct dma_info * info)149 void dma_remove_sysfs_files(struct dma_channel *chan, struct dma_info *info)
150 {
151 struct device *dev = &chan->dev;
152 char name[16];
153
154 device_remove_file(dev, &dev_attr_dev_id);
155 device_remove_file(dev, &dev_attr_count);
156 device_remove_file(dev, &dev_attr_mode);
157 device_remove_file(dev, &dev_attr_flags);
158 device_remove_file(dev, &dev_attr_config);
159
160 snprintf(name, sizeof(name), "dma%d", chan->chan);
161 sysfs_remove_link(&info->pdev->dev.kobj, name);
162
163 device_unregister(dev);
164 }
165