dma-sysfs.c (4175B)
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 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 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} 56postcore_initcall(dma_subsys_init); 57 58static 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 65static 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 74static DEVICE_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id); 75 76static 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 89static DEVICE_ATTR(config, S_IWUSR, NULL, dma_store_config); 90 91static 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 98static 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 107static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode); 108 109#define dma_ro_attr(field, fmt) \ 110static 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} \ 116static DEVICE_ATTR(field, S_IRUGO, dma_show_##field, NULL); 117 118dma_ro_attr(count, "0x%08x\n"); 119dma_ro_attr(flags, "0x%08lx\n"); 120 121int 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 149void 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}