drivers/gpu/drm/udl/udl_main.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 Red Hat
   4  *
   5  * based in parts on udlfb.c:
   6  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
   7  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
   8  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
   9  */
  10
  11 #include <drm/drm.h>
  12 #include <drm/drm_print.h>
  13 #include <drm/drm_probe_helper.h>
  14
  15 #include "udl_drv.h"
  16
  17 /* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
  18 #define BULK_SIZE 512
  19
  20 #define NR_USB_REQUEST_CHANNEL 0x12
  21
  22 #define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
  23 #define WRITES_IN_FLIGHT (4)
  24 #define MAX_VENDOR_DESCRIPTOR_SIZE 256
  25
  26 #define GET_URB_TIMEOUT HZ
  27 #define FREE_URB_TIMEOUT (HZ*2)
  28
  29 static int udl_parse_vendor_descriptor(struct udl_device *udl)
  30 {
  31         struct usb_device *udev = udl_to_usb_device(udl);
  32         char *desc;
  33         char *buf;
  34         char *desc_end;
  35
  36         u8 total_len = 0;
  37
  38         buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
  39         if (!buf)
  40                 return false;
  41         desc = buf;
  42
  43         total_len = usb_get_descriptor(udev, 0x5f, /* vendor specific */
  44                                     0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
  45         if (total_len > 5) {
  46                 DRM_INFO("vendor descriptor length:%x data:%11ph\n",
  47                         total_len, desc);
  48
  49                 if ((desc[0] != total_len) || /* descriptor length */
  50                     (desc[1] != 0x5f) ||   /* vendor descriptor type */
  51                     (desc[2] != 0x01) ||   /* version (2 bytes) */
  52                     (desc[3] != 0x00) ||
  53                     (desc[4] != total_len - 2)) /* length after type */
  54                         goto unrecognized;
  55
  56                 desc_end = desc + total_len;
  57                 desc += 5; /* the fixed header we've already parsed */
  58
  59                 while (desc < desc_end) {
  60                         u8 length;
  61                         u16 key;
  62
  63                         key = le16_to_cpu(*((u16 *) desc));
  64                         desc += sizeof(u16);
  65                         length = *desc;
  66                         desc++;
  67
  68                         switch (key) {
  69                         case 0x0200: { /* max_area */
  70                                 u32 max_area;
  71                                 max_area = le32_to_cpu(*((u32 *)desc));
  72                                 DRM_DEBUG("DL chip limited to %d pixel modes\n",
  73                                         max_area);
  74                                 udl->sku_pixel_limit = max_area;
  75                                 break;
  76                         }
  77                         default:
  78                                 break;
  79                         }
  80                         desc += length;
  81                 }
  82         }
  83
  84         goto success;
  85
  86 unrecognized:
  87         /* allow udlfb to load for now even if firmware unrecognized */
  88         DRM_ERROR("Unrecognized vendor firmware descriptor\n");
  89
  90 success:
  91         kfree(buf);
  92         return true;
  93 }
  94
  95 /*
  96  * Need to ensure a channel is selected before submitting URBs
  97  */
  98 static int udl_select_std_channel(struct udl_device *udl)
  99 {
 100         static const u8 set_def_chn[] = {0x57, 0xCD, 0xDC, 0xA7,
 101                                          0x1C, 0x88, 0x5E, 0x15,
 102                                          0x60, 0xFE, 0xC6, 0x97,
 103                                          0x16, 0x3D, 0x47, 0xF2};
 104
 105         void *sendbuf;
 106         int ret;
 107         struct usb_device *udev = udl_to_usb_device(udl);
 108
 109         sendbuf = kmemdup(set_def_chn, sizeof(set_def_chn), GFP_KERNEL);
 110         if (!sendbuf)
 111                 return -ENOMEM;
 112
 113         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 114                               NR_USB_REQUEST_CHANNEL,
 115                               (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
 116                               sendbuf, sizeof(set_def_chn),
 117                               USB_CTRL_SET_TIMEOUT);
 118         kfree(sendbuf);
 119         return ret < 0 ? ret : 0;
 120 }
 121
 122 static void udl_release_urb_work(struct work_struct *work)
 123 {
 124         struct urb_node *unode = container_of(work, struct urb_node,
 125                                               release_urb_work.work);
 126
 127         up(&unode->dev->urbs.limit_sem);
 128 }
 129
 130 void udl_urb_completion(struct urb *urb)
 131 {
 132         struct urb_node *unode = urb->context;
 133         struct udl_device *udl = unode->dev;
 134         unsigned long flags;
 135
 136         /* sync/async unlink faults aren't errors */
 137         if (urb->status) {
 138                 if (!(urb->status == -ENOENT ||
 139                     urb->status == -ECONNRESET ||
 140                     urb->status == -ESHUTDOWN)) {
 141                         DRM_ERROR("%s - nonzero write bulk status received: %d\n",
 142                                 __func__, urb->status);
 143                 }
 144         }
 145
 146         urb->transfer_buffer_length = udl->urbs.size; /* reset to actual */
 147
 148         spin_lock_irqsave(&udl->urbs.lock, flags);
 149         list_add_tail(&unode->entry, &udl->urbs.list);
 150         udl->urbs.available++;
 151         spin_unlock_irqrestore(&udl->urbs.lock, flags);
 152
 153 #if 0
 154         /*
 155          * When using fb_defio, we deadlock if up() is called
 156          * while another is waiting. So queue to another process.
 157          */
 158         if (fb_defio)
 159                 schedule_delayed_work(&unode->release_urb_work, 0);
 160         else
 161 #endif
 162                 up(&udl->urbs.limit_sem);
 163 }
 164
 165 static void udl_free_urb_list(struct drm_device *dev)
 166 {
 167         struct udl_device *udl = to_udl(dev);
 168         int count = udl->urbs.count;
 169         struct list_head *node;
 170         struct urb_node *unode;
 171         struct urb *urb;
 172
 173         DRM_DEBUG("Waiting for completes and freeing all render urbs\n");
 174
 175         /* keep waiting and freeing, until we've got 'em all */
 176         while (count--) {
 177                 down(&udl->urbs.limit_sem);
 178
 179                 spin_lock_irq(&udl->urbs.lock);
 180
 181                 node = udl->urbs.list.next; /* have reserved one with sem */
 182                 list_del_init(node);
 183
 184                 spin_unlock_irq(&udl->urbs.lock);
 185
 186                 unode = list_entry(node, struct urb_node, entry);
 187                 urb = unode->urb;
 188
 189                 /* Free each separately allocated piece */
 190                 usb_free_coherent(urb->dev, udl->urbs.size,
 191                                   urb->transfer_buffer, urb->transfer_dma);
 192                 usb_free_urb(urb);
 193                 kfree(node);
 194         }
 195         udl->urbs.count = 0;
 196 }
 197
 198 static int udl_alloc_urb_list(struct drm_device *dev, int count, size_t size)
 199 {
 200         struct udl_device *udl = to_udl(dev);
 201         struct urb *urb;
 202         struct urb_node *unode;
 203         char *buf;
 204         size_t wanted_size = count * size;
 205         struct usb_device *udev = udl_to_usb_device(udl);
 206
 207         spin_lock_init(&udl->urbs.lock);
 208
 209 retry:
 210         udl->urbs.size = size;
 211         INIT_LIST_HEAD(&udl->urbs.list);
 212
 213         sema_init(&udl->urbs.limit_sem, 0);
 214         udl->urbs.count = 0;
 215         udl->urbs.available = 0;
 216
 217         while (udl->urbs.count * size < wanted_size) {
 218                 unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
 219                 if (!unode)
 220                         break;
 221                 unode->dev = udl;
 222
 223                 INIT_DELAYED_WORK(&unode->release_urb_work,
 224                           udl_release_urb_work);
 225
 226                 urb = usb_alloc_urb(0, GFP_KERNEL);
 227                 if (!urb) {
 228                         kfree(unode);
 229                         break;
 230                 }
 231                 unode->urb = urb;
 232
 233                 buf = usb_alloc_coherent(udev, size, GFP_KERNEL,
 234                                          &urb->transfer_dma);
 235                 if (!buf) {
 236                         kfree(unode);
 237                         usb_free_urb(urb);
 238                         if (size > PAGE_SIZE) {
 239                                 size /= 2;
 240                                 udl_free_urb_list(dev);
 241                                 goto retry;
 242                         }
 243                         break;
 244                 }
 245
 246                 /* urb->transfer_buffer_length set to actual before submit */
 247                 usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, 1),
 248                                   buf, size, udl_urb_completion, unode);
 249                 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 250
 251                 list_add_tail(&unode->entry, &udl->urbs.list);
 252
 253                 up(&udl->urbs.limit_sem);
 254                 udl->urbs.count++;
 255                 udl->urbs.available++;
 256         }
 257
 258         DRM_DEBUG("allocated %d %d byte urbs\n", udl->urbs.count, (int) size);
 259
 260         return udl->urbs.count;
 261 }
 262
 263 struct urb *udl_get_urb(struct drm_device *dev)
 264 {
 265         struct udl_device *udl = to_udl(dev);
 266         int ret = 0;
 267         struct list_head *entry;
 268         struct urb_node *unode;
 269         struct urb *urb = NULL;
 270
 271         /* Wait for an in-flight buffer to complete and get re-queued */
 272         ret = down_timeout(&udl->urbs.limit_sem, GET_URB_TIMEOUT);
 273         if (ret) {
 274                 DRM_INFO("wait for urb interrupted: %x available: %d\n",
 275                        ret, udl->urbs.available);
 276                 goto error;
 277         }
 278
 279         spin_lock_irq(&udl->urbs.lock);
 280
 281         BUG_ON(list_empty(&udl->urbs.list)); /* reserved one with limit_sem */
 282         entry = udl->urbs.list.next;
 283         list_del_init(entry);
 284         udl->urbs.available--;
 285
 286         spin_unlock_irq(&udl->urbs.lock);
 287
 288         unode = list_entry(entry, struct urb_node, entry);
 289         urb = unode->urb;
 290
 291 error:
 292         return urb;
 293 }
 294
 295 int udl_submit_urb(struct drm_device *dev, struct urb *urb, size_t len)
 296 {
 297         struct udl_device *udl = to_udl(dev);
 298         int ret;
 299
 300         BUG_ON(len > udl->urbs.size);
 301
 302         urb->transfer_buffer_length = len; /* set to actual payload len */
 303         ret = usb_submit_urb(urb, GFP_ATOMIC);
 304         if (ret) {
 305                 udl_urb_completion(urb); /* because no one else will */
 306                 DRM_ERROR("usb_submit_urb error %x\n", ret);
 307         }
 308         return ret;
 309 }
 310
 311 int udl_init(struct udl_device *udl)
 312 {
 313         struct drm_device *dev = &udl->drm;
 314         int ret = -ENOMEM;
 315
 316         DRM_DEBUG("\n");
 317
 318         udl->dmadev = usb_intf_get_dma_device(to_usb_interface(dev->dev));
 319         if (!udl->dmadev)
 320                 drm_warn(dev, "buffer sharing not supported"); /* not an error */
 321
 322         mutex_init(&udl->gem_lock);
 323
 324         if (!udl_parse_vendor_descriptor(udl)) {
 325                 ret = -ENODEV;
 326                 DRM_ERROR("firmware not recognized. Assume incompatible device\n");
 327                 goto err;
 328         }
 329
 330         if (udl_select_std_channel(udl))
 331                 DRM_ERROR("Selecting channel failed\n");
 332
 333         if (!udl_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
 334                 DRM_ERROR("udl_alloc_urb_list failed\n");
 335                 goto err;
 336         }
 337
 338         DRM_DEBUG("\n");
 339         ret = udl_modeset_init(dev);
 340         if (ret)
 341                 goto err;
 342
 343         drm_kms_helper_poll_init(dev);
 344
 345         return 0;
 346
 347 err:
 348         if (udl->urbs.count)
 349                 udl_free_urb_list(dev);
 350         put_device(udl->dmadev);
 351         DRM_ERROR("%d\n", ret);
 352         return ret;
 353 }
 354
 355 int udl_drop_usb(struct drm_device *dev)
 356 {
 357         struct udl_device *udl = to_udl(dev);
 358
 359         udl_free_urb_list(dev);
 360         put_device(udl->dmadev);
 361         udl->dmadev = NULL;
 362
 363         return 0;
 364 }