drivers/misc/mic/bus/vop_bus.c

   1 /*
   2  * Intel MIC Platform Software Stack (MPSS)
   3  *
   4  * Copyright(c) 2016 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * The full GNU General Public License is included in this distribution in
  16  * the file called "COPYING".
  17  *
  18  * Intel Virtio Over PCIe (VOP) Bus driver.
  19  */
  20 #include <linux/slab.h>
  21 #include <linux/module.h>
  22 #include <linux/idr.h>
  23 #include <linux/dma-mapping.h>
  24
  25 #include "vop_bus.h"
  26
  27 static ssize_t device_show(struct device *d,
  28                            struct device_attribute *attr, char *buf)
  29 {
  30         struct vop_device *dev = dev_to_vop(d);
  31
  32         return sprintf(buf, "0x%04x\n", dev->id.device);
  33 }
  34 static DEVICE_ATTR_RO(device);
  35
  36 static ssize_t vendor_show(struct device *d,
  37                            struct device_attribute *attr, char *buf)
  38 {
  39         struct vop_device *dev = dev_to_vop(d);
  40
  41         return sprintf(buf, "0x%04x\n", dev->id.vendor);
  42 }
  43 static DEVICE_ATTR_RO(vendor);
  44
  45 static ssize_t modalias_show(struct device *d,
  46                              struct device_attribute *attr, char *buf)
  47 {
  48         struct vop_device *dev = dev_to_vop(d);
  49
  50         return sprintf(buf, "vop:d%08Xv%08X\n",
  51                        dev->id.device, dev->id.vendor);
  52 }
  53 static DEVICE_ATTR_RO(modalias);
  54
  55 static struct attribute *vop_dev_attrs[] = {
  56         &dev_attr_device.attr,
  57         &dev_attr_vendor.attr,
  58         &dev_attr_modalias.attr,
  59         NULL,
  60 };
  61 ATTRIBUTE_GROUPS(vop_dev);
  62
  63 static inline int vop_id_match(const struct vop_device *dev,
  64                                const struct vop_device_id *id)
  65 {
  66         if (id->device != dev->id.device && id->device != VOP_DEV_ANY_ID)
  67                 return 0;
  68
  69         return id->vendor == VOP_DEV_ANY_ID || id->vendor == dev->id.vendor;
  70 }
  71
  72 /*
  73  * This looks through all the IDs a driver claims to support.  If any of them
  74  * match, we return 1 and the kernel will call vop_dev_probe().
  75  */
  76 static int vop_dev_match(struct device *dv, struct device_driver *dr)
  77 {
  78         unsigned int i;
  79         struct vop_device *dev = dev_to_vop(dv);
  80         const struct vop_device_id *ids;
  81
  82         ids = drv_to_vop(dr)->id_table;
  83         for (i = 0; ids[i].device; i++)
  84                 if (vop_id_match(dev, &ids[i]))
  85                         return 1;
  86         return 0;
  87 }
  88
  89 static int vop_uevent(struct device *dv, struct kobj_uevent_env *env)
  90 {
  91         struct vop_device *dev = dev_to_vop(dv);
  92
  93         return add_uevent_var(env, "MODALIAS=vop:d%08Xv%08X",
  94                               dev->id.device, dev->id.vendor);
  95 }
  96
  97 static int vop_dev_probe(struct device *d)
  98 {
  99         struct vop_device *dev = dev_to_vop(d);
 100         struct vop_driver *drv = drv_to_vop(dev->dev.driver);
 101
 102         return drv->probe(dev);
 103 }
 104
 105 static int vop_dev_remove(struct device *d)
 106 {
 107         struct vop_device *dev = dev_to_vop(d);
 108         struct vop_driver *drv = drv_to_vop(dev->dev.driver);
 109
 110         drv->remove(dev);
 111         return 0;
 112 }
 113
 114 static struct bus_type vop_bus = {
 115         .name  = "vop_bus",
 116         .match = vop_dev_match,
 117         .dev_groups = vop_dev_groups,
 118         .uevent = vop_uevent,
 119         .probe = vop_dev_probe,
 120         .remove = vop_dev_remove,
 121 };
 122
 123 int vop_register_driver(struct vop_driver *driver)
 124 {
 125         driver->driver.bus = &vop_bus;
 126         return driver_register(&driver->driver);
 127 }
 128 EXPORT_SYMBOL_GPL(vop_register_driver);
 129
 130 void vop_unregister_driver(struct vop_driver *driver)
 131 {
 132         driver_unregister(&driver->driver);
 133 }
 134 EXPORT_SYMBOL_GPL(vop_unregister_driver);
 135
 136 static void vop_release_dev(struct device *d)
 137 {
 138         put_device(d);
 139 }
 140
 141 struct vop_device *
 142 vop_register_device(struct device *pdev, int id,
 143                     const struct dma_map_ops *dma_ops,
 144                     struct vop_hw_ops *hw_ops, u8 dnode, struct mic_mw *aper,
 145                     struct dma_chan *chan)
 146 {
 147         int ret;
 148         struct vop_device *vdev;
 149
 150         vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
 151         if (!vdev)
 152                 return ERR_PTR(-ENOMEM);
 153
 154         vdev->dev.parent = pdev;
 155         vdev->id.device = id;
 156         vdev->id.vendor = VOP_DEV_ANY_ID;
 157         vdev->dev.archdata.dma_ops = (struct dma_map_ops *)dma_ops;
 158         vdev->dev.dma_mask = &vdev->dev.coherent_dma_mask;
 159         dma_set_mask(&vdev->dev, DMA_BIT_MASK(64));
 160         vdev->dev.release = vop_release_dev;
 161         vdev->hw_ops = hw_ops;
 162         vdev->dev.bus = &vop_bus;
 163         vdev->dnode = dnode;
 164         vdev->aper = aper;
 165         vdev->dma_ch = chan;
 166         vdev->index = dnode - 1;
 167         dev_set_name(&vdev->dev, "vop-dev%u", vdev->index);
 168         /*
 169          * device_register() causes the bus infrastructure to look for a
 170          * matching driver.
 171          */
 172         ret = device_register(&vdev->dev);
 173         if (ret)
 174                 goto free_vdev;
 175         return vdev;
 176 free_vdev:
 177         kfree(vdev);
 178         return ERR_PTR(ret);
 179 }
 180 EXPORT_SYMBOL_GPL(vop_register_device);
 181
 182 void vop_unregister_device(struct vop_device *dev)
 183 {
 184         device_unregister(&dev->dev);
 185 }
 186 EXPORT_SYMBOL_GPL(vop_unregister_device);
 187
 188 static int __init vop_init(void)
 189 {
 190         return bus_register(&vop_bus);
 191 }
 192
 193 static void __exit vop_exit(void)
 194 {
 195         bus_unregister(&vop_bus);
 196 }
 197
 198 core_initcall(vop_init);
 199 module_exit(vop_exit);
 200
 201 MODULE_AUTHOR("Intel Corporation");
 202 MODULE_DESCRIPTION("Intel(R) VOP Bus driver");
 203 MODULE_LICENSE("GPL v2");