ieee1284_ops.c
上传用户:lgb322
上传日期:2013-02-24
资源大小:30529k
文件大小:23k
- /* IEEE-1284 operations for parport.
- *
- * This file is for generic IEEE 1284 operations. The idea is that
- * they are used by the low-level drivers. If they have a special way
- * of doing something, they can provide their own routines (and put
- * the function pointers in port->ops); if not, they can just use these
- * as a fallback.
- *
- * Note: Make no assumptions about hardware or architecture in this file!
- *
- * Author: Tim Waugh <tim@cyberelk.demon.co.uk>
- * Fixed AUTOFD polarity in ecp_forward_to_reverse(). Fred Barnes, 1999
- * Software emulated EPP fixes, Fred Barnes, 04/2001.
- */
- #include <linux/config.h>
- #include <linux/parport.h>
- #include <linux/delay.h>
- #include <asm/uaccess.h>
- #undef DEBUG /* undef me for production */
- #ifdef CONFIG_LP_CONSOLE
- #undef DEBUG /* Don't want a garbled console */
- #endif
- #ifdef DEBUG
- #define DPRINTK(stuff...) printk (stuff)
- #else
- #define DPRINTK(stuff...)
- #endif
- /*** *
- * One-way data transfer functions. *
- * ***/
- /* Compatibility mode. */
- size_t parport_ieee1284_write_compat (struct parport *port,
- const void *buffer, size_t len,
- int flags)
- {
- int no_irq = 1;
- ssize_t count = 0;
- const unsigned char *addr = buffer;
- unsigned char byte;
- struct pardevice *dev = port->physport->cad;
- unsigned char ctl = (PARPORT_CONTROL_SELECT
- | PARPORT_CONTROL_INIT);
- if (port->irq != PARPORT_IRQ_NONE) {
- parport_enable_irq (port);
- no_irq = 0;
- }
- port->physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
- parport_write_control (port, ctl);
- parport_data_forward (port);
- while (count < len) {
- long expire = jiffies + dev->timeout;
- long wait = (HZ + 99) / 100;
- unsigned char mask = (PARPORT_STATUS_ERROR
- | PARPORT_STATUS_BUSY);
- unsigned char val = (PARPORT_STATUS_ERROR
- | PARPORT_STATUS_BUSY);
- /* Wait until the peripheral's ready */
- do {
- /* Is the peripheral ready yet? */
- if (!parport_wait_peripheral (port, mask, val))
- /* Skip the loop */
- goto ready;
- /* Is the peripheral upset? */
- if ((parport_read_status (port) &
- (PARPORT_STATUS_PAPEROUT |
- PARPORT_STATUS_SELECT |
- PARPORT_STATUS_ERROR))
- != (PARPORT_STATUS_SELECT |
- PARPORT_STATUS_ERROR))
- /* If nFault is asserted (i.e. no
- * error) and PAPEROUT and SELECT are
- * just red herrings, give the driver
- * a chance to check it's happy with
- * that before continuing. */
- goto stop;
- /* Have we run out of time? */
- if (!time_before (jiffies, expire))
- break;
- /* Yield the port for a while. If this is the
- first time around the loop, don't let go of
- the port. This way, we find out if we have
- our interrupt handler called. */
- if (count && no_irq) {
- parport_release (dev);
- __set_current_state (TASK_INTERRUPTIBLE);
- schedule_timeout (wait);
- parport_claim_or_block (dev);
- }
- else
- /* We must have the device claimed here */
- parport_wait_event (port, wait);
- /* Is there a signal pending? */
- if (signal_pending (current))
- break;
- /* Wait longer next time. */
- wait *= 2;
- } while (time_before (jiffies, expire));
- if (signal_pending (current))
- break;
- DPRINTK (KERN_DEBUG "%s: Timed outn", port->name);
- break;
- ready:
- /* Write the character to the data lines. */
- byte = *addr++;
- parport_write_data (port, byte);
- udelay (1);
- /* Pulse strobe. */
- parport_write_control (port, ctl | PARPORT_CONTROL_STROBE);
- udelay (1); /* strobe */
- parport_write_control (port, ctl);
- udelay (1); /* hold */
- /* Assume the peripheral received it. */
- count++;
- /* Let another process run if it needs to. */
- if (time_before (jiffies, expire))
- if (!parport_yield_blocking (dev)
- && current->need_resched)
- schedule ();
- }
- stop:
- port->physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
- return count;
- }
- /* Nibble mode. */
- size_t parport_ieee1284_read_nibble (struct parport *port,
- void *buffer, size_t len,
- int flags)
- {
- #ifndef CONFIG_PARPORT_1284
- return 0;
- #else
- unsigned char *buf = buffer;
- int i;
- unsigned char byte = 0;
- len *= 2; /* in nibbles */
- for (i=0; i < len; i++) {
- unsigned char nibble;
- /* Does the error line indicate end of data? */
- if (((i & 1) == 0) &&
- (parport_read_status(port) & PARPORT_STATUS_ERROR)) {
- port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
- DPRINTK (KERN_DEBUG
- "%s: No more nibble data (%d bytes)n",
- port->name, i/2);
- /* Go to reverse idle phase. */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
- break;
- }
- /* Event 7: Set nAutoFd low. */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- /* Event 9: nAck goes low. */
- port->ieee1284.phase = IEEE1284_PH_REV_DATA;
- if (parport_wait_peripheral (port,
- PARPORT_STATUS_ACK, 0)) {
- /* Timeout -- no more data? */
- DPRINTK (KERN_DEBUG
- "%s: Nibble timeout at event 9 (%d bytes)n",
- port->name, i/2);
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
- break;
- }
- /* Read a nibble. */
- nibble = parport_read_status (port) >> 3;
- nibble &= ~8;
- if ((nibble & 0x10) == 0)
- nibble |= 8;
- nibble &= 0xf;
- /* Event 10: Set nAutoFd high. */
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
- /* Event 11: nAck goes high. */
- if (parport_wait_peripheral (port,
- PARPORT_STATUS_ACK,
- PARPORT_STATUS_ACK)) {
- /* Timeout -- no more data? */
- DPRINTK (KERN_DEBUG
- "%s: Nibble timeout at event 11n",
- port->name);
- break;
- }
- if (i & 1) {
- /* Second nibble */
- byte |= nibble << 4;
- *buf++ = byte;
- } else
- byte = nibble;
- }
- i /= 2; /* i is now in bytes */
- if (i == len) {
- /* Read the last nibble without checking data avail. */
- port = port->physport;
- if (parport_read_status (port) & PARPORT_STATUS_ERROR)
- port->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
- else
- port->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
- }
- return i;
- #endif /* IEEE1284 support */
- }
- /* Byte mode. */
- size_t parport_ieee1284_read_byte (struct parport *port,
- void *buffer, size_t len,
- int flags)
- {
- #ifndef CONFIG_PARPORT_1284
- return 0;
- #else
- unsigned char *buf = buffer;
- ssize_t count = 0;
- for (count = 0; count < len; count++) {
- unsigned char byte;
- /* Data available? */
- if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
- port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
- DPRINTK (KERN_DEBUG
- "%s: No more byte data (%Zd bytes)n",
- port->name, count);
- /* Go to reverse idle phase. */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
- break;
- }
- /* Event 14: Place data bus in high impedance state. */
- parport_data_reverse (port);
- /* Event 7: Set nAutoFd low. */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- /* Event 9: nAck goes low. */
- port->physport->ieee1284.phase = IEEE1284_PH_REV_DATA;
- if (parport_wait_peripheral (port,
- PARPORT_STATUS_ACK,
- 0)) {
- /* Timeout -- no more data? */
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
- 0);
- DPRINTK (KERN_DEBUG "%s: Byte timeout at event 9n",
- port->name);
- break;
- }
- byte = parport_read_data (port);
- *buf++ = byte;
- /* Event 10: Set nAutoFd high */
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
- /* Event 11: nAck goes high. */
- if (parport_wait_peripheral (port,
- PARPORT_STATUS_ACK,
- PARPORT_STATUS_ACK)) {
- /* Timeout -- no more data? */
- DPRINTK (KERN_DEBUG "%s: Byte timeout at event 11n",
- port->name);
- break;
- }
- /* Event 16: Set nStrobe low. */
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE,
- PARPORT_CONTROL_STROBE);
- udelay (5);
- /* Event 17: Set nStrobe high. */
- parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
- }
- if (count == len) {
- /* Read the last byte without checking data avail. */
- port = port->physport;
- if (parport_read_status (port) & PARPORT_STATUS_ERROR)
- port->ieee1284.phase = IEEE1284_PH_HBUSY_DNA;
- else
- port->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
- }
- return count;
- #endif /* IEEE1284 support */
- }
- /*** *
- * ECP Functions. *
- * ***/
- #ifdef CONFIG_PARPORT_1284
- static inline
- int ecp_forward_to_reverse (struct parport *port)
- {
- int retval;
- /* Event 38: Set nAutoFd low */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- parport_data_reverse (port);
- udelay (5);
- /* Event 39: Set nInit low to initiate bus reversal */
- parport_frob_control (port,
- PARPORT_CONTROL_INIT,
- 0);
- /* Event 40: PError goes low */
- retval = parport_wait_peripheral (port,
- PARPORT_STATUS_PAPEROUT, 0);
- if (!retval) {
- DPRINTK (KERN_DEBUG "%s: ECP direction: reversen",
- port->name);
- port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
- } else {
- DPRINTK (KERN_DEBUG "%s: ECP direction: failed to reversen",
- port->name);
- port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
- }
- return retval;
- }
- static inline
- int ecp_reverse_to_forward (struct parport *port)
- {
- int retval;
- /* Event 47: Set nInit high */
- parport_frob_control (port,
- PARPORT_CONTROL_INIT
- | PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_INIT
- | PARPORT_CONTROL_AUTOFD);
- /* Event 49: PError goes high */
- retval = parport_wait_peripheral (port,
- PARPORT_STATUS_PAPEROUT,
- PARPORT_STATUS_PAPEROUT);
- if (!retval) {
- parport_data_forward (port);
- DPRINTK (KERN_DEBUG "%s: ECP direction: forwardn",
- port->name);
- port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
- } else {
- DPRINTK (KERN_DEBUG
- "%s: ECP direction: failed to switch forwardn",
- port->name);
- port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
- }
- return retval;
- }
- #endif /* IEEE1284 support */
- /* ECP mode, forward channel, data. */
- size_t parport_ieee1284_ecp_write_data (struct parport *port,
- const void *buffer, size_t len,
- int flags)
- {
- #ifndef CONFIG_PARPORT_1284
- return 0;
- #else
- const unsigned char *buf = buffer;
- size_t written;
- int retry;
- port = port->physport;
- if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
- if (ecp_reverse_to_forward (port))
- return 0;
- port->ieee1284.phase = IEEE1284_PH_FWD_DATA;
- /* HostAck high (data, not command) */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD
- | PARPORT_CONTROL_STROBE
- | PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_INIT);
- for (written = 0; written < len; written++, buf++) {
- long expire = jiffies + port->cad->timeout;
- unsigned char byte;
- byte = *buf;
- try_again:
- parport_write_data (port, byte);
- parport_frob_control (port, PARPORT_CONTROL_STROBE,
- PARPORT_CONTROL_STROBE);
- udelay (5);
- for (retry = 0; retry < 100; retry++) {
- if (!parport_wait_peripheral (port,
- PARPORT_STATUS_BUSY, 0))
- goto success;
- if (signal_pending (current)) {
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE,
- 0);
- break;
- }
- }
- /* Time for Host Transfer Recovery (page 41 of IEEE1284) */
- DPRINTK (KERN_DEBUG "%s: ECP transfer stalled!n", port->name);
- parport_frob_control (port, PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_INIT);
- udelay (50);
- if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
- /* It's buggered. */
- parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
- break;
- }
- parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
- udelay (50);
- if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
- break;
- DPRINTK (KERN_DEBUG "%s: Host transfer recoveredn",
- port->name);
- if (time_after_eq (jiffies, expire)) break;
- goto try_again;
- success:
- parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
- udelay (5);
- if (parport_wait_peripheral (port,
- PARPORT_STATUS_BUSY,
- PARPORT_STATUS_BUSY))
- /* Peripheral hasn't accepted the data. */
- break;
- }
- port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
- return written;
- #endif /* IEEE1284 support */
- }
- /* ECP mode, reverse channel, data. */
- size_t parport_ieee1284_ecp_read_data (struct parport *port,
- void *buffer, size_t len, int flags)
- {
- #ifndef CONFIG_PARPORT_1284
- return 0;
- #else
- struct pardevice *dev = port->cad;
- unsigned char *buf = buffer;
- int rle_count = 0; /* shut gcc up */
- unsigned char ctl;
- int rle = 0;
- ssize_t count = 0;
- port = port->physport;
- if (port->ieee1284.phase != IEEE1284_PH_REV_IDLE)
- if (ecp_forward_to_reverse (port))
- return 0;
- port->ieee1284.phase = IEEE1284_PH_REV_DATA;
- /* Set HostAck low to start accepting data. */
- ctl = parport_read_control (port);
- ctl &= ~(PARPORT_CONTROL_STROBE | PARPORT_CONTROL_INIT |
- PARPORT_CONTROL_AUTOFD);
- parport_write_control (port,
- ctl | PARPORT_CONTROL_AUTOFD);
- while (count < len) {
- long expire = jiffies + dev->timeout;
- unsigned char byte;
- int command;
- /* Event 43: Peripheral sets nAck low. It can take as
- long as it wants. */
- while (parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0)) {
- /* The peripheral hasn't given us data in
- 35ms. If we have data to give back to the
- caller, do it now. */
- if (count)
- goto out;
- /* If we've used up all the time we were allowed,
- give up altogether. */
- if (!time_before (jiffies, expire))
- goto out;
- /* Yield the port for a while. */
- if (count && dev->port->irq != PARPORT_IRQ_NONE) {
- parport_release (dev);
- __set_current_state (TASK_INTERRUPTIBLE);
- schedule_timeout ((HZ + 24) / 25);
- parport_claim_or_block (dev);
- }
- else
- /* We must have the device claimed here. */
- parport_wait_event (port, (HZ + 24) / 25);
- /* Is there a signal pending? */
- if (signal_pending (current))
- goto out;
- }
- /* Is this a command? */
- if (rle)
- /* The last byte was a run-length count, so
- this can't be as well. */
- command = 0;
- else
- command = (parport_read_status (port) &
- PARPORT_STATUS_BUSY) ? 1 : 0;
- /* Read the data. */
- byte = parport_read_data (port);
- /* If this is a channel command, rather than an RLE
- command or a normal data byte, don't accept it. */
- if (command) {
- if (byte & 0x80) {
- DPRINTK (KERN_DEBUG "%s: stopping short at "
- "channel command (%02x)n",
- port->name, byte);
- goto out;
- }
- else if (port->ieee1284.mode != IEEE1284_MODE_ECPRLE)
- DPRINTK (KERN_DEBUG "%s: device illegally "
- "using RLE; accepting anywayn",
- port->name);
- rle_count = byte + 1;
- /* Are we allowed to read that many bytes? */
- if (rle_count > (len - count)) {
- DPRINTK (KERN_DEBUG "%s: leaving %d RLE bytes "
- "for next timen", port->name,
- rle_count);
- break;
- }
- rle = 1;
- }
- /* Event 44: Set HostAck high, acknowledging handshake. */
- parport_write_control (port, ctl);
- /* Event 45: The peripheral has 35ms to set nAck high. */
- if (parport_wait_peripheral (port, PARPORT_STATUS_ACK,
- PARPORT_STATUS_ACK)) {
- /* It's gone wrong. Return what data we have
- to the caller. */
- DPRINTK (KERN_DEBUG "ECP read timed out at 45n");
- if (command)
- printk (KERN_WARNING
- "%s: command ignored (%02x)n",
- port->name, byte);
- break;
- }
- /* Event 46: Set HostAck low and accept the data. */
- parport_write_control (port,
- ctl | PARPORT_CONTROL_AUTOFD);
- /* If we just read a run-length count, fetch the data. */
- if (command)
- continue;
- /* If this is the byte after a run-length count, decompress. */
- if (rle) {
- rle = 0;
- memset (buf, byte, rle_count);
- buf += rle_count;
- count += rle_count;
- DPRINTK (KERN_DEBUG "%s: decompressed to %d bytesn",
- port->name, rle_count);
- } else {
- /* Normal data byte. */
- *buf = byte;
- buf++, count++;
- }
- }
- out:
- port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
- return count;
- #endif /* IEEE1284 support */
- }
- /* ECP mode, forward channel, commands. */
- size_t parport_ieee1284_ecp_write_addr (struct parport *port,
- const void *buffer, size_t len,
- int flags)
- {
- #ifndef CONFIG_PARPORT_1284
- return 0;
- #else
- const unsigned char *buf = buffer;
- size_t written;
- int retry;
- port = port->physport;
- if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
- if (ecp_reverse_to_forward (port))
- return 0;
- port->ieee1284.phase = IEEE1284_PH_FWD_DATA;
- /* HostAck low (command, not data) */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD
- | PARPORT_CONTROL_STROBE
- | PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_AUTOFD
- | PARPORT_CONTROL_INIT);
- for (written = 0; written < len; written++, buf++) {
- long expire = jiffies + port->cad->timeout;
- unsigned char byte;
- byte = *buf;
- try_again:
- parport_write_data (port, byte);
- parport_frob_control (port, PARPORT_CONTROL_STROBE,
- PARPORT_CONTROL_STROBE);
- udelay (5);
- for (retry = 0; retry < 100; retry++) {
- if (!parport_wait_peripheral (port,
- PARPORT_STATUS_BUSY, 0))
- goto success;
- if (signal_pending (current)) {
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE,
- 0);
- break;
- }
- }
- /* Time for Host Transfer Recovery (page 41 of IEEE1284) */
- DPRINTK (KERN_DEBUG "%s: ECP transfer stalled!n", port->name);
- parport_frob_control (port, PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_INIT);
- udelay (50);
- if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
- /* It's buggered. */
- parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
- break;
- }
- parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
- udelay (50);
- if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
- break;
- DPRINTK (KERN_DEBUG "%s: Host transfer recoveredn",
- port->name);
- if (time_after_eq (jiffies, expire)) break;
- goto try_again;
- success:
- parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
- udelay (5);
- if (parport_wait_peripheral (port,
- PARPORT_STATUS_BUSY,
- PARPORT_STATUS_BUSY))
- /* Peripheral hasn't accepted the data. */
- break;
- }
- port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
- return written;
- #endif /* IEEE1284 support */
- }
- /*** *
- * EPP functions. *
- * ***/
- /* EPP mode, forward channel, data. */
- size_t parport_ieee1284_epp_write_data (struct parport *port,
- const void *buffer, size_t len,
- int flags)
- {
- unsigned char *bp = (unsigned char *) buffer;
- size_t ret = 0;
- /* set EPP idle state (just to make sure) with strobe low */
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE |
- PARPORT_CONTROL_AUTOFD |
- PARPORT_CONTROL_SELECT |
- PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_STROBE |
- PARPORT_CONTROL_INIT);
- port->ops->data_forward (port);
- for (; len > 0; len--, bp++) {
- /* Event 62: Write data and set autofd low */
- parport_write_data (port, *bp);
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- /* Event 58: wait for busy (nWait) to go high */
- if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
- break;
- /* Event 63: set nAutoFd (nDStrb) high */
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
- /* Event 60: wait for busy (nWait) to go low */
- if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
- PARPORT_STATUS_BUSY, 5))
- break;
- ret++;
- }
- /* Event 61: set strobe (nWrite) high */
- parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
- return ret;
- }
- /* EPP mode, reverse channel, data. */
- size_t parport_ieee1284_epp_read_data (struct parport *port,
- void *buffer, size_t len,
- int flags)
- {
- unsigned char *bp = (unsigned char *) buffer;
- unsigned ret = 0;
- /* set EPP idle state (just to make sure) with strobe high */
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE |
- PARPORT_CONTROL_AUTOFD |
- PARPORT_CONTROL_SELECT |
- PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_INIT);
- port->ops->data_reverse (port);
- for (; len > 0; len--, bp++) {
- /* Event 67: set nAutoFd (nDStrb) low */
- parport_frob_control (port,
- PARPORT_CONTROL_AUTOFD,
- PARPORT_CONTROL_AUTOFD);
- /* Event 58: wait for Busy to go high */
- if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
- break;
- }
- *bp = parport_read_data (port);
- /* Event 63: set nAutoFd (nDStrb) high */
- parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
- /* Event 60: wait for Busy to go low */
- if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
- PARPORT_STATUS_BUSY, 5)) {
- break;
- }
- ret++;
- }
- port->ops->data_forward (port);
- return ret;
- }
- /* EPP mode, forward channel, addresses. */
- size_t parport_ieee1284_epp_write_addr (struct parport *port,
- const void *buffer, size_t len,
- int flags)
- {
- unsigned char *bp = (unsigned char *) buffer;
- size_t ret = 0;
- /* set EPP idle state (just to make sure) with strobe low */
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE |
- PARPORT_CONTROL_AUTOFD |
- PARPORT_CONTROL_SELECT |
- PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_STROBE |
- PARPORT_CONTROL_INIT);
- port->ops->data_forward (port);
- for (; len > 0; len--, bp++) {
- /* Event 56: Write data and set nAStrb low. */
- parport_write_data (port, *bp);
- parport_frob_control (port, PARPORT_CONTROL_SELECT,
- PARPORT_CONTROL_SELECT);
- /* Event 58: wait for busy (nWait) to go high */
- if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
- break;
- /* Event 59: set nAStrb high */
- parport_frob_control (port, PARPORT_CONTROL_SELECT, 0);
- /* Event 60: wait for busy (nWait) to go low */
- if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
- PARPORT_STATUS_BUSY, 5))
- break;
- ret++;
- }
- /* Event 61: set strobe (nWrite) high */
- parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
- return ret;
- }
- /* EPP mode, reverse channel, addresses. */
- size_t parport_ieee1284_epp_read_addr (struct parport *port,
- void *buffer, size_t len,
- int flags)
- {
- unsigned char *bp = (unsigned char *) buffer;
- unsigned ret = 0;
- /* Set EPP idle state (just to make sure) with strobe high */
- parport_frob_control (port,
- PARPORT_CONTROL_STROBE |
- PARPORT_CONTROL_AUTOFD |
- PARPORT_CONTROL_SELECT |
- PARPORT_CONTROL_INIT,
- PARPORT_CONTROL_INIT);
- port->ops->data_reverse (port);
- for (; len > 0; len--, bp++) {
- /* Event 64: set nSelectIn (nAStrb) low */
- parport_frob_control (port, PARPORT_CONTROL_SELECT,
- PARPORT_CONTROL_SELECT);
- /* Event 58: wait for Busy to go high */
- if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
- break;
- }
- *bp = parport_read_data (port);
- /* Event 59: set nSelectIn (nAStrb) high */
- parport_frob_control (port, PARPORT_CONTROL_SELECT,
- PARPORT_CONTROL_SELECT);
- /* Event 60: wait for Busy to go low */
- if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
- PARPORT_STATUS_BUSY, 5))
- break;
- ret++;
- }
- port->ops->data_forward (port);
- return ret;
- }