dvb_ca_en50221.c

h内核

/*
 * dvb_ca.c: generic DVB functions for EN50221 CAM interfaces
 *
 * Copyright (C) 2004 Andrew de Quincey
 *
 * Parts of this file were based on sources as follows:
 *
 * Copyright (C) 2003 Ralph Metzler <[e-mail]>
 *
 * based on code:
 *
 * Copyright (C) 1999-2002 Ralph  Metzler
 *                       & Marcus Metzler for convergence integrated media GmbH
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 * Or, point your browser to http://www.gnu.org/copyleft/gpl.html
 */

#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/rwsem.h>

#include "dvb_ca_en50221.h"
#include "dvb_ringbuffer.h"

static int dvb_ca_en50221_debug;

module_param_named(cam_debug, dvb_ca_en50221_debug, int, 0644);
MODULE_PARM_DESC(cam_debug, "enable verbose debug messages");

#define dprintk if (dvb_ca_en50221_debug) printk

#define INIT_TIMEOUT_SECS 5

#define HOST_LINK_BUF_SIZE 0x200

#define RX_BUFFER_SIZE 65535

#define MAX_RX_PACKETS_PER_ITERATION 10

#define CTRLIF_DATA      0
#define CTRLIF_COMMAND   1
#define CTRLIF_STATUS    1
#define CTRLIF_SIZE_LOW  2
#define CTRLIF_SIZE_HIGH 3

#define CMDREG_HC        1 /* Host control */
#define CMDREG_SW        2 /* Size write */
#define CMDREG_SR        4 /* Size read */
#define CMDREG_RS        8 /* Reset interface */
#define CMDREG_FRIE   0x40 /* Enable FR interrupt */
#define CMDREG_DAIE   0x80 /* Enable DA interrupt */
#define IRQEN (CMDREG_DAIE)

#define STATUSREG_RE     1 /* read error */
#define STATUSREG_WE     2 /* write error */
#define STATUSREG_FR  0x40 /* module free */
#define STATUSREG_DA  0x80 /* data available */
#define STATUSREG_TXERR (STATUSREG_RE|STATUSREG_WE) /* general transfer error */


#define DVB_CA_SLOTSTATE_NONE           0
#define DVB_CA_SLOTSTATE_UNINITIALISED  1
#define DVB_CA_SLOTSTATE_RUNNING        2
#define DVB_CA_SLOTSTATE_INVALID        3
#define DVB_CA_SLOTSTATE_WAITREADY      4
#define DVB_CA_SLOTSTATE_VALIDATE       5
#define DVB_CA_SLOTSTATE_WAITFR         6
#define DVB_CA_SLOTSTATE_LINKINIT       7


/* Information on a CA slot */
struct dvb_ca_slot {

        /* current state of the CAM */
        int slot_state;

        /* Number of CAMCHANGES that have occurred since last processing */
        atomic_t camchange_count;

        /* Type of last CAMCHANGE */
        int camchange_type;

        /* base address of CAM config */
        u32 config_base;

        /* value to write into Config Control register */
        u8 config_option;

        /* if 1, the CAM supports DA IRQs */
        u8 da_irq_supported:1;

        /* size of the buffer to use when talking to the CAM */
        int link_buf_size;

        /* semaphore for syncing access to slot structure */
        struct rw_semaphore sem;

        /* buffer for incoming packets */
        struct dvb_ringbuffer rx_buffer;

        /* timer used during various states of the slot */
        unsigned long timeout;
};

/* Private CA-interface information */
struct dvb_ca_private {

        /* pointer back to the public data structure */
        struct dvb_ca_en50221* pub;

        /* the DVB device */
        struct dvb_device *dvbdev;

        /* Flags describing the interface (DVB_CA_FLAG_*) */
        u32 flags;

        /* number of slots supported by this CA interface */
        unsigned int slot_count;

        /* information on each slot */
        struct dvb_ca_slot* slot_info;

        /* wait queues for read() and write() operations */
        wait_queue_head_t wait_queue;

        /* PID of the monitoring thread */
        pid_t thread_pid;

        /* Wait queue used when shutting thread down */
        wait_queue_head_t thread_queue;

        /* Flag indicating when thread should exit */
        int exit:1;

        /* Flag indicating if the CA device is open */
        int open:1;

        /* Flag indicating the thread should wake up now */
        int wakeup:1;

        /* Delay the main thread should use */
        unsigned long delay;

        /* Slot to start looking for data to read from in the next user-space read operation */
        int next_read_slot;
};

static void dvb_ca_en50221_thread_wakeup(struct dvb_ca_private* ca);
static int dvb_ca_en50221_read_data(struct dvb_ca_private* ca, int slot, u8* ebuf, int ecount);
static int dvb_ca_en50221_write_data(struct dvb_ca_private* ca, int slot, u8* ebuf, int ecount);


/**
 * Safely find needle in haystack.
 *
 * @param haystack Buffer to look in.
 * @param hlen Number of bytes in haystack.
 * @param needle Buffer to find.
 * @param nlen Number of bytes in needle.
 * @return Pointer into haystack needle was found at, or NULL if not found.
 */
static u8* findstr(u8* haystack, int hlen, u8* needle, int nlen)
{
        int i;

	if (hlen < nlen)
		return NULL;

        for(i=0; i<= hlen - nlen; i++) {
		if (!strncmp(haystack + i, needle, nlen))
			return haystack + i;
        }

        return NULL;
}



/* ******************************************************************************** */
/* EN50221 physical interface functions */


/**
 * Check CAM status.
 */
static int dvb_ca_en50221_check_camstatus(struct dvb_ca_private* ca, int slot)
{
        int slot_status;
        int cam_present_now;
        int cam_changed;

        /* IRQ mode */
        if (ca->flags & DVB_CA_EN50221_FLAG_IRQ_CAMCHANGE) {
                return (atomic_read(&ca->slot_info[slot].camchange_count) != 0);
        }

        /* poll mode */
	slot_status = ca->pub->poll_slot_status(ca->pub, slot, ca->open);

        cam_present_now = (slot_status & DVB_CA_EN50221_POLL_CAM_PRESENT) ? 1: 0;
        cam_changed = (slot_status & DVB_CA_EN50221_POLL_CAM_CHANGED) ? 1: 0;
        if (!cam_changed) {
                int cam_present_old = (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_NONE);
                cam_changed = (cam_present_now != cam_present_old);
        }

        if (cam_changed) {
                if (!cam_present_now) {
                        ca->slot_info[slot].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
                } else {
                        ca->slot_info[slot].camchange_type = DVB_CA_EN50221_CAMCHANGE_INSERTED;
                }
                atomic_set(&ca->slot_info[slot].camchange_count, 1);
        } else {
                if ((ca->slot_info[slot].slot_state == DVB_CA_SLOTSTATE_WAITREADY) &&
                    (slot_status & DVB_CA_EN50221_POLL_CAM_READY)) {
                        // move to validate state if reset is completed
                        ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_VALIDATE;
                }
        }

        return cam_changed;
}


/**
 * Wait for flags to become set on the STATUS register on a CAM interface,
 * checking for errors and timeout.
 *
 * @param ca CA instance.
 * @param slot Slot on interface.
 * @param waitfor Flags to wait for.
 * @param timeout_ms Timeout in milliseconds.
 *
 * @return 0 on success, nonzero on error.
 */
static int dvb_ca_en50221_wait_if_status(struct dvb_ca_private *ca, int slot,
					 u8 waitfor, int timeout_hz)
{
        unsigned long timeout;
        unsigned long start;

        dprintk ("%s\n", __FUNCTION__);

        /* loop until timeout elapsed */
        start = jiffies;
        timeout = jiffies + timeout_hz;
        while(1) {
                /* read the status and check for error */
                int res = ca->pub->read_cam_control(ca->pub, slot, CTRLIF_STATUS);
		if (res < 0)
			return -EIO;

                /* if we got the flags, it was successful! */
                if (res & waitfor) {
                        dprintk("%s succeeded timeout:%lu\n", __FUNCTION__, jiffies - start);
                        return 0;
                }

                /* check for timeout */
                if (time_after(jiffies, timeout)) {
                        break;
                }

                /* wait for a bit */
                msleep(1);
        }

        dprintk("%s failed timeout:%lu\n", __FUNCTION__, jiffies - start);

        /* if we get here, we've timed out */
        return -ETIMEDOUT;
}


/**
 * Initialise the link layer connection to a CAM.
 *
 * @param ca CA instance.
 * @param slot Slot id.
 *
 * @return 0 on success, nonzero on failure.
 */
static int dvb_ca_en50221_link_init(struct dvb_ca_private* ca, int slot)
{
        int ret;
        int buf_size;
        u8 buf[2];

        dprintk ("%s\n", __FUNCTION__);

        /* we'll be determining these during this function */
        ca->slot_info[slot].da_irq_supported = 0;

        /* set the host link buffer size temporarily. it will be overwritten with the
         * real negotiated size later. */
        ca->slot_info[slot].link_buf_size = 2;

        /* read the buffer size from the CAM */
	if ((ret = ca->pub->write_cam_control(ca->pub, slot, CTRLIF_COMMAND, IRQEN | CMDREG_SR)) != 0)
		return ret;
	if ((ret = dvb_ca_en50221_wait_if_status(ca, slot, STATUSREG_DA, HZ / 10)) != 0)
		return ret;
	if ((ret = dvb_ca_en50221_read_data(ca, slot, buf, 2)) != 2)
		return -EIO;
	if ((ret = ca->pub->write_cam_control(ca->pub, slot, CTRLIF_COMMAND, IRQEN)) != 0)
		return ret;

        /* store it, and choose the minimum of our buffer and the CAM's buffer size */
        buf_size = (buf[0] << 8) | buf[1];
	if (buf_size > HOST_LINK_BUF_SIZE)
		buf_size = HOST_LINK_BUF_SIZE;
        ca->slot_info[slot].link_buf_size = buf_size;
        buf[0] = buf_size >> 8;
        buf[1] = buf_size & 0xff;
        dprintk("Chosen link buffer size of %i\n", buf_size);

        /* write the buffer size to the CAM */
	if ((ret = ca->pub->write_cam_control(ca->pub, slot, CTRLIF_COMMAND, IRQEN | CMDREG_SW)) != 0)
		return ret;
	if ((ret = dvb_ca_en50221_wait_if_status(ca, slot, STATUSREG_FR, HZ / 10)) != 0)
		return ret;
	if ((ret = dvb_ca_en50221_write_data(ca, slot, buf, 2)) != 2)
		return -EIO;
	if ((ret = ca->pub->write_cam_control(ca->pub, slot, CTRLIF_COMMAND, IRQEN)) != 0)
		return ret;

        /* success */
        return 0;
}

/**
 * Read a tuple from attribute memory.
 *
 * @param ca CA instance.
 * @param slot Slot id.
 * @param address Address to read from. Updated.
 * @param tupleType Tuple id byte. Updated.
 * @param tupleLength Tuple length. Updated.
 * @param tuple Dest buffer for tuple (must be 256 bytes). Updated.
 *
 * @return 0 on success, nonzero on error.
 */
static int dvb_ca_en50221_read_tuple(struct dvb_ca_private* ca, int slot,
                                     int* address, int* tupleType, int* tupleLength, u8* tuple)
{
        int i;
        int _tupleType;
        int _tupleLength;
        int _address = *address;

        /* grab the next tuple length and type */
	if ((_tupleType = ca->pub->read_attribute_mem(ca->pub, slot, _address)) < 0)
		return _tupleType;
        if (_tupleType == 0xff) {
                dprintk("END OF CHAIN TUPLE type:0x%x\n", _tupleType);
                *address += 2;
                *tupleType = _tupleType;
                *tupleLength = 0;
                return 0;
        }
	if ((_tupleLength = ca->pub->read_attribute_mem(ca->pub, slot, _address + 2)) < 0)
		return _tupleLength;
        _address += 4;

        dprintk("TUPLE type:0x%x length:%i\n", _tupleType, _tupleLength);

        /* read in the whole tuple */
        for(i=0; i< _tupleLength; i++) {
                tuple[i] = ca->pub->read_attribute_mem(ca->pub, slot, _address + (i*2));
		dprintk("  0x%02x: 0x%02x %c\n",
			i, tuple[i] & 0xff,
			((tuple[i] > 31) && (tuple[i] < 127)) ? tuple[i] : '.');
        }
        _address += (_tupleLength*2);

        // success
        *tupleType = _tupleType;
        *tupleLength = _tupleLength;
        *address = _address;
        return 0;
}


/**
 * Parse attribute memory of a CAM module, extracting Config register, and checking
 * it is a DVB CAM module.
 *
 * @param ca CA instance.
 * @param slot Slot id.
 *
 * @return 0 on success, <0 on failure.
 */
static int dvb_ca_en50221_parse_attributes(struct dvb_ca_private* ca, int slot)
{
        int address = 0;
        int tupleLength;
        int tupleType;
        u8 tuple[257];
        char* dvb_str;
        int rasz;
        int status;
        int got_cftableentry = 0;
        int end_chain = 0;
        int i;
        u16 manfid = 0;
        u16 devid = 0;


        // CISTPL_DEVICE_0A
	if ((status =
	     dvb_ca_en50221_read_tuple(ca, slot, &address, &tupleType, &tupleLength, tuple)) < 0)
		return status;
	if (tupleType != 0x1D)
		return -EINVAL;



        // CISTPL_DEVICE_0C
	if ((status =
	     dvb_ca_en50221_read_tuple(ca, slot, &address, &tupleType, &tupleLength, tuple)) < 0)
		return status;
	if (tupleType != 0x1C)
		return -EINVAL;



        // CISTPL_VERS_1