arch/sh/drivers/dma/dma-sysfs.c

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