dtl1_cs.c

嵌入式Linux的蓝牙模块驱动

/*
 *
 *  A driver for Nokia Connectivity Card DTL-1 devices
 *
 *  Copyright (C) 2001-2002  Marcel Holtmann <[e-mail]>
 *
 *
 *  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
 *  <[e-mail]>.  Portions created by David A. Hinds
 *  are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
 *
 */

#include <linux/config.h>
#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>

#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/serial.h>
#include <linux/serial_reg.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/io.h>

#include <pcmcia/version.h>
#include <pcmcia/cs_types.h>
#include <pcmcia/cs.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 ======================== */


/* Bit map of interrupts to choose from */
static u_int irq_mask = 0xffff;
static int irq_list[4] = { -1 };

MODULE_PARM(irq_mask, "i");
MODULE_PARM(irq_list, "1-4i");

MODULE_AUTHOR("Marcel Holtmann <[e-mail]>");
MODULE_DESCRIPTION("Bluetooth driver for Nokia Connectivity Card DTL-1");
MODULE_LICENSE("GPL");



/* ======================== Local structures ======================== */


typedef struct dtl1_info_t {
	dev_link_t link;
	dev_node_t node;

	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;


void dtl1_config(dev_link_t *link);
void dtl1_release(dev_link_t *link);
int dtl1_event(event_t event, int priority, event_callback_args_t *args);

static dev_info_t dev_info = "dtl1_cs";

dev_link_t *dtl1_attach(void);
void dtl1_detach(dev_link_t *);

static dev_link_t *dev_list = NULL;


/* 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;
} __attribute__ ((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->link.io.BasePort1;
		register struct sk_buff *skb;
		register int len;

		clear_bit(XMIT_WAKEUP, &(info->tx_state));

		if (!(info->link.state & DEV_PRESENT))
			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("\n");

	/* 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->link.io.BasePort1;

	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:
				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 (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;
					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", 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, struct pt_regs *regs)
{
	dtl1_info_t *info = dev_inst;
	unsigned int iobase;
	unsigned char msr;
	int boguscount = 0;
	int iir, lsr;

	if (!info || !info->hdev) {
		BT_ERR("Call of irq %d for unknown device", irq);
		return IRQ_NONE;
	}

	iobase = info->link.io.BasePort1;

	spin_lock(&(info->lock));

	iir = inb(iobase + UART_IIR) & UART_IIR_ID;
	while (iir) {

		/* 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);
	}

	spin_unlock(&(info->lock));

	return IRQ_HANDLED;
}



/* ======================== 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 (skb->pkt_type) {
	case HCI_COMMAND_PKT:
		hdev->stat.cmd_tx++;
		nsh.type = 0x81;
		break;
	case HCI_ACLDATA_PKT: