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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/parport/ieee1284_ops.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/parport/ieee1284_ops.c')
-rw-r--r-- | drivers/parport/ieee1284_ops.c | 921 |
1 files changed, 921 insertions, 0 deletions
diff --git a/drivers/parport/ieee1284_ops.c b/drivers/parport/ieee1284_ops.c new file mode 100644 index 000000000000..6624278c6ed8 --- /dev/null +++ b/drivers/parport/ieee1284_ops.c @@ -0,0 +1,921 @@ +/* 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/module.h> +#include <linux/parport.h> +#include <linux/delay.h> +#include <linux/sched.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) { + unsigned 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 out\n", 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) + && 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 11\n", + 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 9\n", + 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 11\n", + 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: reverse\n", + port->name); + port->ieee1284.phase = IEEE1284_PH_REV_IDLE; + } else { + DPRINTK (KERN_DEBUG "%s: ECP direction: failed to reverse\n", + 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: forward\n", + port->name); + port->ieee1284.phase = IEEE1284_PH_FWD_IDLE; + } else { + DPRINTK (KERN_DEBUG + "%s: ECP direction: failed to switch forward\n", + 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++) { + unsigned 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 recovered\n", + 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) { + unsigned 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 anyway\n", + 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 time\n", 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 45\n"); + + 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 bytes\n", + 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++) { + unsigned 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 recovered\n", + 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; +} + +EXPORT_SYMBOL(parport_ieee1284_ecp_write_data); +EXPORT_SYMBOL(parport_ieee1284_ecp_read_data); +EXPORT_SYMBOL(parport_ieee1284_ecp_write_addr); +EXPORT_SYMBOL(parport_ieee1284_write_compat); +EXPORT_SYMBOL(parport_ieee1284_read_nibble); +EXPORT_SYMBOL(parport_ieee1284_read_byte); +EXPORT_SYMBOL(parport_ieee1284_epp_write_data); +EXPORT_SYMBOL(parport_ieee1284_epp_read_data); +EXPORT_SYMBOL(parport_ieee1284_epp_write_addr); +EXPORT_SYMBOL(parport_ieee1284_epp_read_addr); |