linux/arch/sh/drivers/dma/dma-sysfs.c
<<
>>
Prefs
   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}
 165