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
18static const struct bus_type dma_subsys = {
19	.name = "dma",
20	.dev_name = "dma",
21};
22
23static 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
44static DEVICE_ATTR(devices, S_IRUGO, dma_show_devices, NULL);
45
46static 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}
62postcore_initcall(dma_subsys_init);
63
64static 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
71static 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
80static DEVICE_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
81
82static 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
95static DEVICE_ATTR(config, S_IWUSR, NULL, dma_store_config);
96
97static 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
104static 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
113static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
114
115#define dma_ro_attr(field, fmt)						\
116static 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}									\
122static DEVICE_ATTR(field, S_IRUGO, dma_show_##field, NULL);
123
124dma_ro_attr(count, "0x%08x\n");
125dma_ro_attr(flags, "0x%08lx\n");
126
127int 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
155void 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