/*
   * FireDTV driver -- firewire I/O backend
   */
  
  #include <linux/device.h>
  #include <linux/errno.h>
  #include <linux/firewire.h>
  #include <linux/firewire-constants.h>
  #include <linux/kernel.h>
  #include <linux/list.h>
  #include <linux/mm.h>
  #include <linux/mod_devicetable.h>
  #include <linux/module.h>
  #include <linux/mutex.h>
  #include <linux/slab.h>
  #include <linux/spinlock.h>
  #include <linux/string.h>
  #include <linux/types.h>
  #include <linux/wait.h>
  #include <linux/workqueue.h>
  
  #include <asm/page.h>
  
  #include <dvb_demux.h>
  
  #include "firedtv.h"
  
  static LIST_HEAD(node_list);
  static DEFINE_SPINLOCK(node_list_lock);
  
  static inline struct fw_device *device_of(struct firedtv *fdtv)
  {
  	return fw_device(fdtv->device->parent);
  }
  
  static int node_req(struct firedtv *fdtv, u64 addr, void *data, size_t len,
  		    int tcode)
  {
  	struct fw_device *device = device_of(fdtv);
  	int rcode, generation = device->generation;
  
  	smp_rmb(); /* node_id vs. generation */
  
  	rcode = fw_run_transaction(device->card, tcode, device->node_id,
  			generation, device->max_speed, addr, data, len);
  
  	return rcode != RCODE_COMPLETE ? -EIO : 0;
  }
  
  int fdtv_lock(struct firedtv *fdtv, u64 addr, void *data)
  {
  	return node_req(fdtv, addr, data, 8, TCODE_LOCK_COMPARE_SWAP);
  }
  
  int fdtv_read(struct firedtv *fdtv, u64 addr, void *data)
  {
  	return node_req(fdtv, addr, data, 4, TCODE_READ_QUADLET_REQUEST);
  }
  
  int fdtv_write(struct firedtv *fdtv, u64 addr, void *data, size_t len)
  {
  	return node_req(fdtv, addr, data, len, TCODE_WRITE_BLOCK_REQUEST);
  }
  
  #define ISO_HEADER_SIZE			4
  #define CIP_HEADER_SIZE			8
  #define MPEG2_TS_HEADER_SIZE		4
  #define MPEG2_TS_SOURCE_PACKET_SIZE	(4 + 188)
  
  #define MAX_PACKET_SIZE		1024  /* 776, rounded up to 2^n */
  #define PACKETS_PER_PAGE	(PAGE_SIZE / MAX_PACKET_SIZE)
  #define N_PACKETS		64    /* buffer size */
  #define N_PAGES			DIV_ROUND_UP(N_PACKETS, PACKETS_PER_PAGE)
  #define IRQ_INTERVAL		16
  
  struct fdtv_ir_context {
  	struct fw_iso_context *context;
  	struct fw_iso_buffer buffer;
  	int interrupt_packet;
  	int current_packet;
  	char *pages[N_PAGES];
  };
  
  static int queue_iso(struct fdtv_ir_context *ctx, int index)
  {
  	struct fw_iso_packet p;
  
  	p.payload_length = MAX_PACKET_SIZE;
  	p.interrupt = !(++ctx->interrupt_packet & (IRQ_INTERVAL - 1));
  	p.skip = 0;
  	p.header_length = ISO_HEADER_SIZE;
  
  	return fw_iso_context_queue(ctx->context, &p, &ctx->buffer,
  				    index * MAX_PACKET_SIZE);
  }
  
  static void handle_iso(struct fw_iso_context *context, u32 cycle,
  		       size_t header_length, void *header, void *data)
  {
  	struct firedtv *fdtv = data;
  	struct fdtv_ir_context *ctx = fdtv->ir_context;
  	__be32 *h, *h_end;
  	int length, err, i = ctx->current_packet;
  	char *p, *p_end;
  
  	for (h = header, h_end = h + header_length / 4; h < h_end; h++) {
  		length = be32_to_cpup(h) >> 16;
  		if (unlikely(length > MAX_PACKET_SIZE)) {
  			dev_err(fdtv->device, "length = %d
  ", length);
  			length = MAX_PACKET_SIZE;
  		}
  
  		p = ctx->pages[i / PACKETS_PER_PAGE]
  				+ (i % PACKETS_PER_PAGE) * MAX_PACKET_SIZE;
  		p_end = p + length;
  
  		for (p += CIP_HEADER_SIZE + MPEG2_TS_HEADER_SIZE; p < p_end;
  		     p += MPEG2_TS_SOURCE_PACKET_SIZE)
  			dvb_dmx_swfilter_packets(&fdtv->demux, p, 1);
  
  		err = queue_iso(ctx, i);
  		if (unlikely(err))
  			dev_err(fdtv->device, "requeue failed
  ");
  
  		i = (i + 1) & (N_PACKETS - 1);
  	}
  	fw_iso_context_queue_flush(ctx->context);
  	ctx->current_packet = i;
  }
  
  int fdtv_start_iso(struct firedtv *fdtv)
  {
  	struct fdtv_ir_context *ctx;
  	struct fw_device *device = device_of(fdtv);
  	int i, err;
  
  	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
  	if (!ctx)
  		return -ENOMEM;
  
  	ctx->context = fw_iso_context_create(device->card,
  			FW_ISO_CONTEXT_RECEIVE, fdtv->isochannel,
  			device->max_speed, ISO_HEADER_SIZE, handle_iso, fdtv);
  	if (IS_ERR(ctx->context)) {
  		err = PTR_ERR(ctx->context);
  		goto fail_free;
  	}
  
  	err = fw_iso_buffer_init(&ctx->buffer, device->card,
  				 N_PAGES, DMA_FROM_DEVICE);
  	if (err)
  		goto fail_context_destroy;
  
  	ctx->interrupt_packet = 0;
  	ctx->current_packet = 0;
  
  	for (i = 0; i < N_PAGES; i++)
  		ctx->pages[i] = page_address(ctx->buffer.pages[i]);
  
  	for (i = 0; i < N_PACKETS; i++) {
  		err = queue_iso(ctx, i);
  		if (err)
  			goto fail;
  	}
  
  	err = fw_iso_context_start(ctx->context, -1, 0,
  				   FW_ISO_CONTEXT_MATCH_ALL_TAGS);
  	if (err)
  		goto fail;
  
  	fdtv->ir_context = ctx;
  
  	return 0;
  fail:
  	fw_iso_buffer_destroy(&ctx->buffer, device->card);
  fail_context_destroy:
  	fw_iso_context_destroy(ctx->context);
  fail_free:
  	kfree(ctx);
  
  	return err;
  }
  
  void fdtv_stop_iso(struct firedtv *fdtv)
  {
  	struct fdtv_ir_context *ctx = fdtv->ir_context;
  
  	fw_iso_context_stop(ctx->context);
  	fw_iso_buffer_destroy(&ctx->buffer, device_of(fdtv)->card);
  	fw_iso_context_destroy(ctx->context);
  	kfree(ctx);
  }
  
  static void handle_fcp(struct fw_card *card, struct fw_request *request,
  		       int tcode, int destination, int source, int generation,
  		       unsigned long long offset, void *payload, size_t length,
  		       void *callback_data)
  {
  	struct firedtv *f, *fdtv = NULL;
  	struct fw_device *device;
  	unsigned long flags;
  	int su;
  
  	if (length < 2 || (((u8 *)payload)[0] & 0xf0) != 0)
  		return;
  
  	su = ((u8 *)payload)[1] & 0x7;
  
  	spin_lock_irqsave(&node_list_lock, flags);
  	list_for_each_entry(f, &node_list, list) {
  		device = device_of(f);
  		if (device->generation != generation)
  			continue;
  
  		smp_rmb(); /* node_id vs. generation */
  
  		if (device->card == card &&
  		    device->node_id == source &&
  		    (f->subunit == su || (f->subunit == 0 && su == 0x7))) {
  			fdtv = f;
  			break;
  		}
  	}
  	spin_unlock_irqrestore(&node_list_lock, flags);
  
  	if (fdtv)
  		avc_recv(fdtv, payload, length);
  }
  
  static struct fw_address_handler fcp_handler = {
  	.length           = CSR_FCP_END - CSR_FCP_RESPONSE,
  	.address_callback = handle_fcp,
  };
  
  static const struct fw_address_region fcp_region = {
  	.start	= CSR_REGISTER_BASE + CSR_FCP_RESPONSE,
  	.end	= CSR_REGISTER_BASE + CSR_FCP_END,
  };
  
  static const char * const model_names[] = {
  	[FIREDTV_UNKNOWN] = "unknown type",
  	[FIREDTV_DVB_S]   = "FireDTV S/CI",
  	[FIREDTV_DVB_C]   = "FireDTV C/CI",
  	[FIREDTV_DVB_T]   = "FireDTV T/CI",
  	[FIREDTV_DVB_S2]  = "FireDTV S2  ",
  };
  
  /* Adjust the template string if models with longer names appear. */
  #define MAX_MODEL_NAME_LEN sizeof("FireDTV ????")
  
  static int node_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
  {
  	struct firedtv *fdtv;
  	char name[MAX_MODEL_NAME_LEN];
  	int name_len, i, err;
  
  	fdtv = kzalloc(sizeof(*fdtv), GFP_KERNEL);
  	if (!fdtv)
  		return -ENOMEM;
  
  	dev_set_drvdata(&unit->device, fdtv);
  	fdtv->device		= &unit->device;
  	fdtv->isochannel	= -1;
  	fdtv->voltage		= 0xff;
  	fdtv->tone		= 0xff;
  
  	mutex_init(&fdtv->avc_mutex);
  	init_waitqueue_head(&fdtv->avc_wait);
  	mutex_init(&fdtv->demux_mutex);
  	INIT_WORK(&fdtv->remote_ctrl_work, avc_remote_ctrl_work);
  
  	name_len = fw_csr_string(unit->directory, CSR_MODEL,
  				 name, sizeof(name));
  	for (i = ARRAY_SIZE(model_names); --i; )
  		if (strlen(model_names[i]) <= name_len &&
  		    strncmp(name, model_names[i], name_len) == 0)
  			break;
  	fdtv->type = i;
  
  	err = fdtv_register_rc(fdtv, &unit->device);
  	if (err)
  		goto fail_free;
  
  	spin_lock_irq(&node_list_lock);
  	list_add_tail(&fdtv->list, &node_list);
  	spin_unlock_irq(&node_list_lock);
  
  	err = avc_identify_subunit(fdtv);
  	if (err)
  		goto fail;
  
  	err = fdtv_dvb_register(fdtv, model_names[fdtv->type]);
  	if (err)
  		goto fail;
  
  	avc_register_remote_control(fdtv);
  
  	return 0;
  fail:
  	spin_lock_irq(&node_list_lock);
  	list_del(&fdtv->list);
  	spin_unlock_irq(&node_list_lock);
  	fdtv_unregister_rc(fdtv);
  fail_free:
  	kfree(fdtv);
  
  	return err;
  }
  
  static void node_remove(struct fw_unit *unit)
  {
  	struct firedtv *fdtv = dev_get_drvdata(&unit->device);
  
  	fdtv_dvb_unregister(fdtv);
  
  	spin_lock_irq(&node_list_lock);
  	list_del(&fdtv->list);
  	spin_unlock_irq(&node_list_lock);
  
  	fdtv_unregister_rc(fdtv);
  
  	kfree(fdtv);
  }
  
  static void node_update(struct fw_unit *unit)
  {
  	struct firedtv *fdtv = dev_get_drvdata(&unit->device);
  
  	if (fdtv->isochannel >= 0)
  		cmp_establish_pp_connection(fdtv, fdtv->subunit,
  					    fdtv->isochannel);
  }
  
  #define MATCH_FLAGS (IEEE1394_MATCH_VENDOR_ID | IEEE1394_MATCH_MODEL_ID | \
  		     IEEE1394_MATCH_SPECIFIER_ID | IEEE1394_MATCH_VERSION)
  
  #define DIGITAL_EVERYWHERE_OUI	0x001287
  #define AVC_UNIT_SPEC_ID_ENTRY	0x00a02d
  #define AVC_SW_VERSION_ENTRY	0x010001
  
  static const struct ieee1394_device_id fdtv_id_table[] = {
  	{
  		/* FloppyDTV S/CI and FloppyDTV S2 */
  		.match_flags	= MATCH_FLAGS,
  		.vendor_id	= DIGITAL_EVERYWHERE_OUI,
  		.model_id	= 0x000024,
  		.specifier_id	= AVC_UNIT_SPEC_ID_ENTRY,
  		.version	= AVC_SW_VERSION_ENTRY,
  	}, {
  		/* FloppyDTV T/CI */
  		.match_flags	= MATCH_FLAGS,
  		.vendor_id	= DIGITAL_EVERYWHERE_OUI,
  		.model_id	= 0x000025,
  		.specifier_id	= AVC_UNIT_SPEC_ID_ENTRY,
  		.version	= AVC_SW_VERSION_ENTRY,
  	}, {
  		/* FloppyDTV C/CI */
  		.match_flags	= MATCH_FLAGS,
  		.vendor_id	= DIGITAL_EVERYWHERE_OUI,
  		.model_id	= 0x000026,
  		.specifier_id	= AVC_UNIT_SPEC_ID_ENTRY,
  		.version	= AVC_SW_VERSION_ENTRY,
  	}, {
  		/* FireDTV S/CI and FloppyDTV S2 */
  		.match_flags	= MATCH_FLAGS,
  		.vendor_id	= DIGITAL_EVERYWHERE_OUI,
  		.model_id	= 0x000034,
  		.specifier_id	= AVC_UNIT_SPEC_ID_ENTRY,
  		.version	= AVC_SW_VERSION_ENTRY,
  	}, {
  		/* FireDTV T/CI */
  		.match_flags	= MATCH_FLAGS,
  		.vendor_id	= DIGITAL_EVERYWHERE_OUI,
  		.model_id	= 0x000035,
  		.specifier_id	= AVC_UNIT_SPEC_ID_ENTRY,
  		.version	= AVC_SW_VERSION_ENTRY,
  	}, {
  		/* FireDTV C/CI */
  		.match_flags	= MATCH_FLAGS,
  		.vendor_id	= DIGITAL_EVERYWHERE_OUI,
  		.model_id	= 0x000036,
  		.specifier_id	= AVC_UNIT_SPEC_ID_ENTRY,
  		.version	= AVC_SW_VERSION_ENTRY,
  	}, {}
  };
  MODULE_DEVICE_TABLE(ieee1394, fdtv_id_table);
  
  static struct fw_driver fdtv_driver = {
  	.driver   = {
  		.owner  = THIS_MODULE,
  		.name   = "firedtv",
  		.bus    = &fw_bus_type,
  	},
  	.probe    = node_probe,
  	.update   = node_update,
  	.remove   = node_remove,
  	.id_table = fdtv_id_table,
  };
  
  static int __init fdtv_init(void)
  {
  	int ret;
  
  	ret = fw_core_add_address_handler(&fcp_handler, &fcp_region);
  	if (ret < 0)
  		return ret;
  
  	ret = driver_register(&fdtv_driver.driver);
  	if (ret < 0)
  		fw_core_remove_address_handler(&fcp_handler);
  
  	return ret;
  }
  
  static void __exit fdtv_exit(void)
  {
  	driver_unregister(&fdtv_driver.driver);
  	fw_core_remove_address_handler(&fcp_handler);
  }
  
  module_init(fdtv_init);
  module_exit(fdtv_exit);
  
  MODULE_AUTHOR("Andreas Monitzer <andy@monitzer.com>");
  MODULE_AUTHOR("Ben Backx <ben@bbackx.com>");
  MODULE_DESCRIPTION("FireDTV DVB Driver");
  MODULE_LICENSE("GPL");
  MODULE_SUPPORTED_DEVICE("FireDTV DVB");