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

   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
  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
  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
  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
  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
  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
  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
  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
 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
 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 }