/*
   *
   *  A driver for Nokia Connectivity Card DTL-1 devices
   *
   *  Copyright (C) 2001-2002  Marcel Holtmann <marcel@holtmann.org>
   *
   *
   *  This program is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License version 2 as
   *  published by the Free Software Foundation;
   *
   *  Software distributed under the License is distributed on an "AS
   *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
   *  implied. See the License for the specific language governing
   *  rights and limitations under the License.
   *
   *  The initial developer of the original code is David A. Hinds
   *  <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
   *  are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
   *
   */

  #include <linux/module.h>
  
  #include <linux/kernel.h>
  #include <linux/init.h>
  #include <linux/slab.h>
  #include <linux/types.h>

  #include <linux/delay.h>
  #include <linux/errno.h>
  #include <linux/ptrace.h>
  #include <linux/ioport.h>
  #include <linux/spinlock.h>
  #include <linux/moduleparam.h>
  
  #include <linux/skbuff.h>
  #include <linux/string.h>
  #include <linux/serial.h>
  #include <linux/serial_reg.h>
  #include <linux/bitops.h>
  #include <asm/system.h>
  #include <asm/io.h>

  #include <pcmcia/cistpl.h>
  #include <pcmcia/ciscode.h>
  #include <pcmcia/ds.h>
  #include <pcmcia/cisreg.h>
  
  #include <net/bluetooth/bluetooth.h>
  #include <net/bluetooth/hci_core.h>
  
  
  
  /* ======================== Module parameters ======================== */
  
  
  MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
  MODULE_DESCRIPTION("Bluetooth driver for Nokia Connectivity Card DTL-1");
  MODULE_LICENSE("GPL");
  
  
  
  /* ======================== Local structures ======================== */
  
  
  typedef struct dtl1_info_t {

  	struct pcmcia_device *p_dev;

  
  	struct hci_dev *hdev;
  
  	spinlock_t lock;		/* For serializing operations */
  
  	unsigned long flowmask;		/* HCI flow mask */
  	int ri_latch;
  
  	struct sk_buff_head txq;
  	unsigned long tx_state;
  
  	unsigned long rx_state;
  	unsigned long rx_count;
  	struct sk_buff *rx_skb;
  } dtl1_info_t;

  static int dtl1_config(struct pcmcia_device *link);

  static void dtl1_release(struct pcmcia_device *link);

  static void dtl1_detach(struct pcmcia_device *p_dev);

  
  /* Transmit states  */
  #define XMIT_SENDING  1
  #define XMIT_WAKEUP   2
  #define XMIT_WAITING  8
  
  /* Receiver States */
  #define RECV_WAIT_NSH   0
  #define RECV_WAIT_DATA  1
  
  
  typedef struct {
  	u8 type;
  	u8 zero;
  	u16 len;

  } __packed nsh_t;	/* Nokia Specific Header */

  
  #define NSHL  4				/* Nokia Specific Header Length */
  
  
  
  /* ======================== Interrupt handling ======================== */
  
  
  static int dtl1_write(unsigned int iobase, int fifo_size, __u8 *buf, int len)
  {
  	int actual = 0;
  
  	/* Tx FIFO should be empty */
  	if (!(inb(iobase + UART_LSR) & UART_LSR_THRE))
  		return 0;
  
  	/* Fill FIFO with current frame */
  	while ((fifo_size-- > 0) && (actual < len)) {
  		/* Transmit next byte */
  		outb(buf[actual], iobase + UART_TX);
  		actual++;
  	}
  
  	return actual;
  }
  
  
  static void dtl1_write_wakeup(dtl1_info_t *info)
  {
  	if (!info) {
  		BT_ERR("Unknown device");
  		return;
  	}
  
  	if (test_bit(XMIT_WAITING, &(info->tx_state))) {
  		set_bit(XMIT_WAKEUP, &(info->tx_state));
  		return;
  	}
  
  	if (test_and_set_bit(XMIT_SENDING, &(info->tx_state))) {
  		set_bit(XMIT_WAKEUP, &(info->tx_state));
  		return;
  	}
  
  	do {

  		register unsigned int iobase = info->p_dev->resource[0]->start;

  		register struct sk_buff *skb;
  		register int len;
  
  		clear_bit(XMIT_WAKEUP, &(info->tx_state));

  		if (!pcmcia_dev_present(info->p_dev))

  			return;
  
  		if (!(skb = skb_dequeue(&(info->txq))))
  			break;
  
  		/* Send frame */
  		len = dtl1_write(iobase, 32, skb->data, skb->len);
  
  		if (len == skb->len) {
  			set_bit(XMIT_WAITING, &(info->tx_state));
  			kfree_skb(skb);
  		} else {
  			skb_pull(skb, len);
  			skb_queue_head(&(info->txq), skb);
  		}
  
  		info->hdev->stat.byte_tx += len;
  
  	} while (test_bit(XMIT_WAKEUP, &(info->tx_state)));
  
  	clear_bit(XMIT_SENDING, &(info->tx_state));
  }
  
  
  static void dtl1_control(dtl1_info_t *info, struct sk_buff *skb)
  {
  	u8 flowmask = *(u8 *)skb->data;
  	int i;
  
  	printk(KERN_INFO "Bluetooth: Nokia control data =");
  	for (i = 0; i < skb->len; i++) {
  		printk(" %02x", skb->data[i]);
  	}
  	printk("
  ");
  
  	/* transition to active state */
  	if (((info->flowmask & 0x07) == 0) && ((flowmask & 0x07) != 0)) {
  		clear_bit(XMIT_WAITING, &(info->tx_state));
  		dtl1_write_wakeup(info);
  	}
  
  	info->flowmask = flowmask;
  
  	kfree_skb(skb);
  }
  
  
  static void dtl1_receive(dtl1_info_t *info)
  {
  	unsigned int iobase;
  	nsh_t *nsh;
  	int boguscount = 0;
  
  	if (!info) {
  		BT_ERR("Unknown device");
  		return;
  	}

  	iobase = info->p_dev->resource[0]->start;

  
  	do {
  		info->hdev->stat.byte_rx++;
  
  		/* Allocate packet */
  		if (info->rx_skb == NULL)
  			if (!(info->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC))) {
  				BT_ERR("Can't allocate mem for new packet");
  				info->rx_state = RECV_WAIT_NSH;
  				info->rx_count = NSHL;
  				return;
  			}
  
  		*skb_put(info->rx_skb, 1) = inb(iobase + UART_RX);
  		nsh = (nsh_t *)info->rx_skb->data;
  
  		info->rx_count--;
  
  		if (info->rx_count == 0) {
  
  			switch (info->rx_state) {
  			case RECV_WAIT_NSH:
  				info->rx_state = RECV_WAIT_DATA;
  				info->rx_count = nsh->len + (nsh->len & 0x0001);
  				break;
  			case RECV_WAIT_DATA:

  				bt_cb(info->rx_skb)->pkt_type = nsh->type;

  
  				/* remove PAD byte if it exists */
  				if (nsh->len & 0x0001) {
  					info->rx_skb->tail--;
  					info->rx_skb->len--;
  				}
  
  				/* remove NSH */
  				skb_pull(info->rx_skb, NSHL);

  				switch (bt_cb(info->rx_skb)->pkt_type) {

  				case 0x80:
  					/* control data for the Nokia Card */
  					dtl1_control(info, info->rx_skb);
  					break;
  				case 0x82:
  				case 0x83:
  				case 0x84:
  					/* send frame to the HCI layer */
  					info->rx_skb->dev = (void *) info->hdev;

  					bt_cb(info->rx_skb)->pkt_type &= 0x0f;

  					hci_recv_frame(info->rx_skb);
  					break;
  				default:
  					/* unknown packet */

  					BT_ERR("Unknown HCI packet with type 0x%02x received", bt_cb(info->rx_skb)->pkt_type);

  					kfree_skb(info->rx_skb);
  					break;
  				}
  
  				info->rx_state = RECV_WAIT_NSH;
  				info->rx_count = NSHL;
  				info->rx_skb = NULL;
  				break;
  			}
  
  		}
  
  		/* Make sure we don't stay here too long */
  		if (boguscount++ > 32)
  			break;
  
  	} while (inb(iobase + UART_LSR) & UART_LSR_DR);
  }

  static irqreturn_t dtl1_interrupt(int irq, void *dev_inst)

  {
  	dtl1_info_t *info = dev_inst;
  	unsigned int iobase;
  	unsigned char msr;
  	int boguscount = 0;
  	int iir, lsr;

  	irqreturn_t r = IRQ_NONE;

  	if (!info || !info->hdev)
  		/* our irq handler is shared */
  		return IRQ_NONE;

  	iobase = info->p_dev->resource[0]->start;

  
  	spin_lock(&(info->lock));
  
  	iir = inb(iobase + UART_IIR) & UART_IIR_ID;
  	while (iir) {

  		r = IRQ_HANDLED;

  		/* Clear interrupt */
  		lsr = inb(iobase + UART_LSR);
  
  		switch (iir) {
  		case UART_IIR_RLSI:
  			BT_ERR("RLSI");
  			break;
  		case UART_IIR_RDI:
  			/* Receive interrupt */
  			dtl1_receive(info);
  			break;
  		case UART_IIR_THRI:
  			if (lsr & UART_LSR_THRE) {
  				/* Transmitter ready for data */
  				dtl1_write_wakeup(info);
  			}
  			break;
  		default:
  			BT_ERR("Unhandled IIR=%#x", iir);
  			break;
  		}
  
  		/* Make sure we don't stay here too long */
  		if (boguscount++ > 100)
  			break;
  
  		iir = inb(iobase + UART_IIR) & UART_IIR_ID;
  
  	}
  
  	msr = inb(iobase + UART_MSR);
  
  	if (info->ri_latch ^ (msr & UART_MSR_RI)) {
  		info->ri_latch = msr & UART_MSR_RI;
  		clear_bit(XMIT_WAITING, &(info->tx_state));
  		dtl1_write_wakeup(info);

  		r = IRQ_HANDLED;

  	}
  
  	spin_unlock(&(info->lock));

  	return r;

  }
  
  
  
  /* ======================== HCI interface ======================== */
  
  
  static int dtl1_hci_open(struct hci_dev *hdev)
  {
  	set_bit(HCI_RUNNING, &(hdev->flags));
  
  	return 0;
  }
  
  
  static int dtl1_hci_flush(struct hci_dev *hdev)
  {
  	dtl1_info_t *info = (dtl1_info_t *)(hdev->driver_data);
  
  	/* Drop TX queue */
  	skb_queue_purge(&(info->txq));
  
  	return 0;
  }
  
  
  static int dtl1_hci_close(struct hci_dev *hdev)
  {
  	if (!test_and_clear_bit(HCI_RUNNING, &(hdev->flags)))
  		return 0;
  
  	dtl1_hci_flush(hdev);
  
  	return 0;
  }
  
  
  static int dtl1_hci_send_frame(struct sk_buff *skb)
  {
  	dtl1_info_t *info;
  	struct hci_dev *hdev = (struct hci_dev *)(skb->dev);
  	struct sk_buff *s;
  	nsh_t nsh;
  
  	if (!hdev) {
  		BT_ERR("Frame for unknown HCI device (hdev=NULL)");
  		return -ENODEV;
  	}
  
  	info = (dtl1_info_t *)(hdev->driver_data);

  	switch (bt_cb(skb)->pkt_type) {

  	case HCI_COMMAND_PKT:
  		hdev->stat.cmd_tx++;
  		nsh.type = 0x81;
  		break;
  	case HCI_ACLDATA_PKT:
  		hdev->stat.acl_tx++;
  		nsh.type = 0x82;
  		break;
  	case HCI_SCODATA_PKT:
  		hdev->stat.sco_tx++;
  		nsh.type = 0x83;
  		break;

  	default:
  		return -EILSEQ;

  	};
  
  	nsh.zero = 0;
  	nsh.len = skb->len;
  
  	s = bt_skb_alloc(NSHL + skb->len + 1, GFP_ATOMIC);

  	if (!s)
  		return -ENOMEM;

  	skb_reserve(s, NSHL);

  	skb_copy_from_linear_data(skb, skb_put(s, skb->len), skb->len);

  	if (skb->len & 0x0001)
  		*skb_put(s, 1) = 0;	/* PAD */
  
  	/* Prepend skb with Nokia frame header and queue */
  	memcpy(skb_push(s, NSHL), &nsh, NSHL);
  	skb_queue_tail(&(info->txq), s);
  
  	dtl1_write_wakeup(info);
  
  	kfree_skb(skb);
  
  	return 0;
  }
  
  
  static void dtl1_hci_destruct(struct hci_dev *hdev)
  {
  }
  
  
  static int dtl1_hci_ioctl(struct hci_dev *hdev, unsigned int cmd,  unsigned long arg)
  {
  	return -ENOIOCTLCMD;
  }
  
  
  
  /* ======================== Card services HCI interaction ======================== */
  
  
  static int dtl1_open(dtl1_info_t *info)
  {
  	unsigned long flags;

  	unsigned int iobase = info->p_dev->resource[0]->start;

  	struct hci_dev *hdev;
  
  	spin_lock_init(&(info->lock));
  
  	skb_queue_head_init(&(info->txq));
  
  	info->rx_state = RECV_WAIT_NSH;
  	info->rx_count = NSHL;
  	info->rx_skb = NULL;
  
  	set_bit(XMIT_WAITING, &(info->tx_state));
  
  	/* Initialize HCI device */
  	hdev = hci_alloc_dev();
  	if (!hdev) {
  		BT_ERR("Can't allocate HCI device");
  		return -ENOMEM;
  	}
  
  	info->hdev = hdev;

  	hdev->bus = HCI_PCCARD;

  	hdev->driver_data = info;

  	SET_HCIDEV_DEV(hdev, &info->p_dev->dev);

  
  	hdev->open     = dtl1_hci_open;
  	hdev->close    = dtl1_hci_close;
  	hdev->flush    = dtl1_hci_flush;
  	hdev->send     = dtl1_hci_send_frame;
  	hdev->destruct = dtl1_hci_destruct;
  	hdev->ioctl    = dtl1_hci_ioctl;
  
  	hdev->owner = THIS_MODULE;
  
  	spin_lock_irqsave(&(info->lock), flags);
  
  	/* Reset UART */
  	outb(0, iobase + UART_MCR);
  
  	/* Turn off interrupts */
  	outb(0, iobase + UART_IER);
  
  	/* Initialize UART */
  	outb(UART_LCR_WLEN8, iobase + UART_LCR);	/* Reset DLAB */
  	outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase + UART_MCR);

  	info->ri_latch = inb(info->p_dev->resource[0]->start + UART_MSR)
  				& UART_MSR_RI;

  
  	/* Turn on interrupts */
  	outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
  
  	spin_unlock_irqrestore(&(info->lock), flags);
  
  	/* Timeout before it is safe to send the first HCI packet */
  	msleep(2000);
  
  	/* Register HCI device */
  	if (hci_register_dev(hdev) < 0) {
  		BT_ERR("Can't register HCI device");
  		info->hdev = NULL;
  		hci_free_dev(hdev);
  		return -ENODEV;
  	}
  
  	return 0;
  }
  
  
  static int dtl1_close(dtl1_info_t *info)
  {
  	unsigned long flags;

  	unsigned int iobase = info->p_dev->resource[0]->start;

  	struct hci_dev *hdev = info->hdev;
  
  	if (!hdev)
  		return -ENODEV;
  
  	dtl1_hci_close(hdev);
  
  	spin_lock_irqsave(&(info->lock), flags);
  
  	/* Reset UART */
  	outb(0, iobase + UART_MCR);
  
  	/* Turn off interrupts */
  	outb(0, iobase + UART_IER);
  
  	spin_unlock_irqrestore(&(info->lock), flags);

  	hci_unregister_dev(hdev);

  	hci_free_dev(hdev);
  
  	return 0;
  }

  static int dtl1_probe(struct pcmcia_device *link)

  {
  	dtl1_info_t *info;

  
  	/* Create new info device */

  	info = kzalloc(sizeof(*info), GFP_KERNEL);

  	if (!info)

  		return -ENOMEM;

  	info->p_dev = link;

  	link->priv = info;

  	link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_IO;

  	return dtl1_config(link);

  }

  static void dtl1_detach(struct pcmcia_device *link)

  {
  	dtl1_info_t *info = link->priv;

  	dtl1_release(link);

  	kfree(info);
  }

  static int dtl1_confcheck(struct pcmcia_device *p_dev, void *priv_data)

  {

  	if ((p_dev->resource[1]->end) || (p_dev->resource[1]->end < 8))

  		return -ENODEV;

  	p_dev->resource[0]->flags &= ~IO_DATA_PATH_WIDTH;
  	p_dev->resource[0]->flags |= IO_DATA_PATH_WIDTH_8;

  	return pcmcia_request_io(p_dev);

  }

  static int dtl1_config(struct pcmcia_device *link)

  {

  	dtl1_info_t *info = link->priv;

  	int i;

  	/* Look for a generic full-sized window */

  	link->resource[0]->end = 8;

  	if (pcmcia_loop_config(link, dtl1_confcheck, NULL) < 0)

  		goto failed;

  	i = pcmcia_request_irq(link, dtl1_interrupt);

  	if (i != 0)

  		goto failed;

  	i = pcmcia_enable_device(link);

  	if (i != 0)

  		goto failed;

  
  	if (dtl1_open(info) != 0)
  		goto failed;

  	return 0;

  failed:
  	dtl1_release(link);

  	return -ENODEV;

  }

  static void dtl1_release(struct pcmcia_device *link)

  {
  	dtl1_info_t *info = link->priv;

  	dtl1_close(info);

  	pcmcia_disable_device(link);

  }

  static const struct pcmcia_device_id dtl1_ids[] = {

  	PCMCIA_DEVICE_PROD_ID12("Nokia Mobile Phones", "DTL-1", 0xe1bfdd64, 0xe168480d),

  	PCMCIA_DEVICE_PROD_ID12("Nokia Mobile Phones", "DTL-4", 0xe1bfdd64, 0x9102bc82),

  	PCMCIA_DEVICE_PROD_ID12("Socket", "CF", 0xb38bcc2e, 0x44ebf863),

  	PCMCIA_DEVICE_PROD_ID12("Socket", "CF+ Personal Network Card", 0xb38bcc2e, 0xe732bae3),

  	PCMCIA_DEVICE_NULL
  };
  MODULE_DEVICE_TABLE(pcmcia, dtl1_ids);

  static struct pcmcia_driver dtl1_driver = {
  	.owner		= THIS_MODULE,

  	.name		= "dtl1_cs",

  	.probe		= dtl1_probe,

  	.remove		= dtl1_detach,

  	.id_table	= dtl1_ids,

  };
  
  static int __init init_dtl1_cs(void)
  {
  	return pcmcia_register_driver(&dtl1_driver);
  }
  
  
  static void __exit exit_dtl1_cs(void)
  {
  	pcmcia_unregister_driver(&dtl1_driver);

  }
  
  module_init(init_dtl1_cs);
  module_exit(exit_dtl1_cs);