drivers/media/dvb/firewire/firedtv-fw.c

   1 /*
   2  * FireDTV driver -- firewire I/O backend
   3  */
   4
   5 #include <linux/device.h>
   6 #include <linux/errno.h>
   7 #include <linux/firewire.h>
   8 #include <linux/firewire-constants.h>
   9 #include <linux/kernel.h>
  10 #include <linux/list.h>
  11 #include <linux/mm.h>
  12 #include <linux/slab.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/types.h>
  15
  16 #include <asm/page.h>
  17
  18 #include <dvb_demux.h>
  19
  20 #include "firedtv.h"
  21
  22 static LIST_HEAD(node_list);
  23 static DEFINE_SPINLOCK(node_list_lock);
  24
  25 static inline struct fw_device *device_of(struct firedtv *fdtv)
  26 {
  27         return fw_device(fdtv->device->parent);
  28 }
  29
  30 static int node_req(struct firedtv *fdtv, u64 addr, void *data, size_t len,
  31                     int tcode)
  32 {
  33         struct fw_device *device = device_of(fdtv);
  34         int rcode, generation = device->generation;
  35
  36         smp_rmb(); /* node_id vs. generation */
  37
  38         rcode = fw_run_transaction(device->card, tcode, device->node_id,
  39                         generation, device->max_speed, addr, data, len);
  40
  41         return rcode != RCODE_COMPLETE ? -EIO : 0;
  42 }
  43
  44 static int node_lock(struct firedtv *fdtv, u64 addr, void *data)
  45 {
  46         return node_req(fdtv, addr, data, 8, TCODE_LOCK_COMPARE_SWAP);
  47 }
  48
  49 static int node_read(struct firedtv *fdtv, u64 addr, void *data)
  50 {
  51         return node_req(fdtv, addr, data, 4, TCODE_READ_QUADLET_REQUEST);
  52 }
  53
  54 static int node_write(struct firedtv *fdtv, u64 addr, void *data, size_t len)
  55 {
  56         return node_req(fdtv, addr, data, len, TCODE_WRITE_BLOCK_REQUEST);
  57 }
  58
  59 #define ISO_HEADER_SIZE                 4
  60 #define CIP_HEADER_SIZE                 8
  61 #define MPEG2_TS_HEADER_SIZE            4
  62 #define MPEG2_TS_SOURCE_PACKET_SIZE     (4 + 188)
  63
  64 #define MAX_PACKET_SIZE         1024  /* 776, rounded up to 2^n */
  65 #define PACKETS_PER_PAGE        (PAGE_SIZE / MAX_PACKET_SIZE)
  66 #define N_PACKETS               64    /* buffer size */
  67 #define N_PAGES                 DIV_ROUND_UP(N_PACKETS, PACKETS_PER_PAGE)
  68 #define IRQ_INTERVAL            16
  69
  70 struct firedtv_receive_context {
  71         struct fw_iso_context *context;
  72         struct fw_iso_buffer buffer;
  73         int interrupt_packet;
  74         int current_packet;
  75         char *pages[N_PAGES];
  76 };
  77
  78 static int queue_iso(struct firedtv_receive_context *ctx, int index)
  79 {
  80         struct fw_iso_packet p;
  81
  82         p.payload_length = MAX_PACKET_SIZE;
  83         p.interrupt = !(++ctx->interrupt_packet & (IRQ_INTERVAL - 1));
  84         p.skip = 0;
  85         p.header_length = ISO_HEADER_SIZE;
  86
  87         return fw_iso_context_queue(ctx->context, &p, &ctx->buffer,
  88                                     index * MAX_PACKET_SIZE);
  89 }
  90
  91 static void handle_iso(struct fw_iso_context *context, u32 cycle,
  92                        size_t header_length, void *header, void *data)
  93 {
  94         struct firedtv *fdtv = data;
  95         struct firedtv_receive_context *ctx = fdtv->backend_data;
  96         __be32 *h, *h_end;
  97         int length, err, i = ctx->current_packet;
  98         char *p, *p_end;
  99
 100         for (h = header, h_end = h + header_length / 4; h < h_end; h++) {
 101                 length = be32_to_cpup(h) >> 16;
 102                 if (unlikely(length > MAX_PACKET_SIZE)) {
 103                         dev_err(fdtv->device, "length = %d\n", length);
 104                         length = MAX_PACKET_SIZE;
 105                 }
 106
 107                 p = ctx->pages[i / PACKETS_PER_PAGE]
 108                                 + (i % PACKETS_PER_PAGE) * MAX_PACKET_SIZE;
 109                 p_end = p + length;
 110
 111                 for (p += CIP_HEADER_SIZE + MPEG2_TS_HEADER_SIZE; p < p_end;
 112                      p += MPEG2_TS_SOURCE_PACKET_SIZE)
 113                         dvb_dmx_swfilter_packets(&fdtv->demux, p, 1);
 114
 115                 err = queue_iso(ctx, i);
 116                 if (unlikely(err))
 117                         dev_err(fdtv->device, "requeue failed\n");
 118
 119                 i = (i + 1) & (N_PACKETS - 1);
 120         }
 121         ctx->current_packet = i;
 122 }
 123
 124 static int start_iso(struct firedtv *fdtv)
 125 {
 126         struct firedtv_receive_context *ctx;
 127         struct fw_device *device = device_of(fdtv);
 128         int i, err;
 129
 130         ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
 131         if (!ctx)
 132                 return -ENOMEM;
 133
 134         ctx->context = fw_iso_context_create(device->card,
 135                         FW_ISO_CONTEXT_RECEIVE, fdtv->isochannel,
 136                         device->max_speed, ISO_HEADER_SIZE, handle_iso, fdtv);
 137         if (IS_ERR(ctx->context)) {
 138                 err = PTR_ERR(ctx->context);
 139                 goto fail_free;
 140         }
 141
 142         err = fw_iso_buffer_init(&ctx->buffer, device->card,
 143                                  N_PAGES, DMA_FROM_DEVICE);
 144         if (err)
 145                 goto fail_context_destroy;
 146
 147         ctx->interrupt_packet = 0;
 148         ctx->current_packet = 0;
 149
 150         for (i = 0; i < N_PAGES; i++)
 151                 ctx->pages[i] = page_address(ctx->buffer.pages[i]);
 152
 153         for (i = 0; i < N_PACKETS; i++) {
 154                 err = queue_iso(ctx, i);
 155                 if (err)
 156                         goto fail;
 157         }
 158
 159         err = fw_iso_context_start(ctx->context, -1, 0,
 160                                    FW_ISO_CONTEXT_MATCH_ALL_TAGS);
 161         if (err)
 162                 goto fail;
 163
 164         fdtv->backend_data = ctx;
 165
 166         return 0;
 167 fail:
 168         fw_iso_buffer_destroy(&ctx->buffer, device->card);
 169 fail_context_destroy:
 170         fw_iso_context_destroy(ctx->context);
 171 fail_free:
 172         kfree(ctx);
 173
 174         return err;
 175 }
 176
 177 static void stop_iso(struct firedtv *fdtv)
 178 {
 179         struct firedtv_receive_context *ctx = fdtv->backend_data;
 180
 181         fw_iso_context_stop(ctx->context);
 182         fw_iso_buffer_destroy(&ctx->buffer, device_of(fdtv)->card);
 183         fw_iso_context_destroy(ctx->context);
 184         kfree(ctx);
 185 }
 186
 187 static const struct firedtv_backend backend = {
 188         .lock           = node_lock,
 189         .read           = node_read,
 190         .write          = node_write,
 191         .start_iso      = start_iso,
 192         .stop_iso       = stop_iso,
 193 };
 194
 195 static void handle_fcp(struct fw_card *card, struct fw_request *request,
 196                        int tcode, int destination, int source, int generation,
 197                        int speed, unsigned long long offset,
 198                        void *payload, size_t length, void *callback_data)
 199 {
 200         struct firedtv *f, *fdtv = NULL;
 201         struct fw_device *device;
 202         unsigned long flags;
 203         int su;
 204
 205         if (length < 2 || (((u8 *)payload)[0] & 0xf0) != 0)
 206                 return;
 207
 208         su = ((u8 *)payload)[1] & 0x7;
 209
 210         spin_lock_irqsave(&node_list_lock, flags);
 211         list_for_each_entry(f, &node_list, list) {
 212                 device = device_of(f);
 213                 if (device->generation != generation)
 214                         continue;
 215
 216                 smp_rmb(); /* node_id vs. generation */
 217
 218                 if (device->card == card &&
 219                     device->node_id == source &&
 220                     (f->subunit == su || (f->subunit == 0 && su == 0x7))) {
 221                         fdtv = f;
 222                         break;
 223                 }
 224         }
 225         spin_unlock_irqrestore(&node_list_lock, flags);
 226
 227         if (fdtv)
 228                 avc_recv(fdtv, payload, length);
 229 }
 230
 231 static struct fw_address_handler fcp_handler = {
 232         .length           = CSR_FCP_END - CSR_FCP_RESPONSE,
 233         .address_callback = handle_fcp,
 234 };
 235
 236 static const struct fw_address_region fcp_region = {
 237         .start  = CSR_REGISTER_BASE + CSR_FCP_RESPONSE,
 238         .end    = CSR_REGISTER_BASE + CSR_FCP_END,
 239 };
 240
 241 /* Adjust the template string if models with longer names appear. */
 242 #define MAX_MODEL_NAME_LEN sizeof("FireDTV ????")
 243
 244 static int node_probe(struct device *dev)
 245 {
 246         struct firedtv *fdtv;
 247         char name[MAX_MODEL_NAME_LEN];
 248         int name_len, err;
 249
 250         name_len = fw_csr_string(fw_unit(dev)->directory, CSR_MODEL,
 251                                  name, sizeof(name));
 252
 253         fdtv = fdtv_alloc(dev, &backend, name, name_len >= 0 ? name_len : 0);
 254         if (!fdtv)
 255                 return -ENOMEM;
 256
 257         err = fdtv_register_rc(fdtv, dev);
 258         if (err)
 259                 goto fail_free;
 260
 261         spin_lock_irq(&node_list_lock);
 262         list_add_tail(&fdtv->list, &node_list);
 263         spin_unlock_irq(&node_list_lock);
 264
 265         err = avc_identify_subunit(fdtv);
 266         if (err)
 267                 goto fail;
 268
 269         err = fdtv_dvb_register(fdtv);
 270         if (err)
 271                 goto fail;
 272
 273         avc_register_remote_control(fdtv);
 274
 275         return 0;
 276 fail:
 277         spin_lock_irq(&node_list_lock);
 278         list_del(&fdtv->list);
 279         spin_unlock_irq(&node_list_lock);
 280         fdtv_unregister_rc(fdtv);
 281 fail_free:
 282         kfree(fdtv);
 283
 284         return err;
 285 }
 286
 287 static int node_remove(struct device *dev)
 288 {
 289         struct firedtv *fdtv = dev_get_drvdata(dev);
 290
 291         fdtv_dvb_unregister(fdtv);
 292
 293         spin_lock_irq(&node_list_lock);
 294         list_del(&fdtv->list);
 295         spin_unlock_irq(&node_list_lock);
 296
 297         fdtv_unregister_rc(fdtv);
 298
 299         kfree(fdtv);
 300         return 0;
 301 }
 302
 303 static void node_update(struct fw_unit *unit)
 304 {
 305         struct firedtv *fdtv = dev_get_drvdata(&unit->device);
 306
 307         if (fdtv->isochannel >= 0)
 308                 cmp_establish_pp_connection(fdtv, fdtv->subunit,
 309                                             fdtv->isochannel);
 310 }
 311
 312 static struct fw_driver fdtv_driver = {
 313         .driver   = {
 314                 .owner  = THIS_MODULE,
 315                 .name   = "firedtv",
 316                 .bus    = &fw_bus_type,
 317                 .probe  = node_probe,
 318                 .remove = node_remove,
 319         },
 320         .update   = node_update,
 321         .id_table = fdtv_id_table,
 322 };
 323
 324 int __init fdtv_fw_init(void)
 325 {
 326         int ret;
 327
 328         ret = fw_core_add_address_handler(&fcp_handler, &fcp_region);
 329         if (ret < 0)
 330                 return ret;
 331
 332         return driver_register(&fdtv_driver.driver);
 333 }
 334
 335 void fdtv_fw_exit(void)
 336 {
 337         driver_unregister(&fdtv_driver.driver);
 338         fw_core_remove_address_handler(&fcp_handler);
 339 }