linux/drivers/char/ser_a2232.c

822 lines
25 KiB
C
Raw Normal View History

/* drivers/char/ser_a2232.c */
/* $Id: ser_a2232.c,v 0.4 2000/01/25 12:00:00 ehaase Exp $ */
/* Linux serial driver for the Amiga A2232 board */
/* This driver is MAINTAINED. Before applying any changes, please contact
* the author.
*/
/* Copyright (c) 2000-2001 Enver Haase <ehaase@inf.fu-berlin.de>
* alias The A2232 driver project <A2232@gmx.net>
* All rights reserved.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
/***************************** Documentation ************************/
/*
* This driver is in EXPERIMENTAL state. That means I could not find
* someone with five A2232 boards with 35 ports running at 19200 bps
* at the same time and test the machine's behaviour.
* However, I know that you can performance-tweak this driver (see
* the source code).
* One thing to consider is the time this driver consumes during the
* Amiga's vertical blank interrupt. Everything that is to be done
* _IS DONE_ when entering the vertical blank interrupt handler of
* this driver.
* However, it would be more sane to only do the job for only ONE card
* instead of ALL cards at a time; or, more generally, to handle only
* SOME ports instead of ALL ports at a time.
* However, as long as no-one runs into problems I guess I shouldn't
* change the driver as it runs fine for me :) .
*
* Version history of this file:
* 0.4 Resolved licensing issues.
* 0.3 Inclusion in the Linux/m68k tree, small fixes.
* 0.2 Added documentation, minor typo fixes.
* 0.1 Initial release.
*
* TO DO:
* - Handle incoming BREAK events. I guess "Stevens: Advanced
* Programming in the UNIX(R) Environment" is a good reference
* on what is to be done.
* - When installing as a module, don't simply 'printk' text, but
* send it to the TTY used by the user.
*
* THANKS TO:
* - Jukka Marin (65EC02 code).
* - The other NetBSD developers on whose A2232 driver I had a
* pretty close look. However, I didn't copy any code so it
* is okay to put my code under the GPL and include it into
* Linux.
*/
/***************************** End of Documentation *****************/
/***************************** Defines ******************************/
/*
* Enables experimental 115200 (normal) 230400 (turbo) baud rate.
* The A2232 specification states it can only operate at speeds up to
* 19200 bits per second, and I was not able to send a file via
* "sz"/"rz" and a null-modem cable from one A2232 port to another
* at 115200 bits per second.
* However, this might work for you.
*/
#undef A2232_SPEEDHACK
/*
* Default is not to use RTS/CTS so you could be talked to death.
*/
#define A2232_SUPPRESS_RTSCTS_WARNING
/************************* End of Defines ***************************/
/***************************** Includes *****************************/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/tty.h>
#include <asm/setup.h>
#include <asm/amigaints.h>
#include <asm/amigahw.h>
#include <linux/zorro.h>
#include <asm/irq.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/serial.h>
#include <linux/generic_serial.h>
#include <linux/tty_flip.h>
#include "ser_a2232.h"
#include "ser_a2232fw.h"
/************************* End of Includes **************************/
/***************************** Prototypes ***************************/
/* The interrupt service routine */
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
static irqreturn_t a2232_vbl_inter(int irq, void *data);
/* Initialize the port structures */
static void a2232_init_portstructs(void);
/* Initialize and register TTY drivers. */
/* returns 0 IFF successful */
static int a2232_init_drivers(void);
/* BEGIN GENERIC_SERIAL PROTOTYPES */
static void a2232_disable_tx_interrupts(void *ptr);
static void a2232_enable_tx_interrupts(void *ptr);
static void a2232_disable_rx_interrupts(void *ptr);
static void a2232_enable_rx_interrupts(void *ptr);
static int a2232_get_CD(void *ptr);
static void a2232_shutdown_port(void *ptr);
static int a2232_set_real_termios(void *ptr);
static int a2232_chars_in_buffer(void *ptr);
static void a2232_close(void *ptr);
static void a2232_hungup(void *ptr);
/* static void a2232_getserial (void *ptr, struct serial_struct *sp); */
/* END GENERIC_SERIAL PROTOTYPES */
/* Functions that the TTY driver struct expects */
static int a2232_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg);
static void a2232_throttle(struct tty_struct *tty);
static void a2232_unthrottle(struct tty_struct *tty);
static int a2232_open(struct tty_struct * tty, struct file * filp);
/************************* End of Prototypes ************************/
/***************************** Global variables *********************/
/*---------------------------------------------------------------------------
* Interface from generic_serial.c back here
*--------------------------------------------------------------------------*/
static struct real_driver a2232_real_driver = {
a2232_disable_tx_interrupts,
a2232_enable_tx_interrupts,
a2232_disable_rx_interrupts,
a2232_enable_rx_interrupts,
a2232_get_CD,
a2232_shutdown_port,
a2232_set_real_termios,
a2232_chars_in_buffer,
a2232_close,
a2232_hungup,
NULL /* a2232_getserial */
};
static void *a2232_driver_ID = &a2232_driver_ID; // Some memory address WE own.
/* Ports structs */
static struct a2232_port a2232_ports[MAX_A2232_BOARDS*NUMLINES];
/* TTY driver structs */
static struct tty_driver *a2232_driver;
/* nr of cards completely (all ports) and correctly configured */
static int nr_a2232;
/* zorro_dev structs for the A2232's */
static struct zorro_dev *zd_a2232[MAX_A2232_BOARDS];
/***************************** End of Global variables **************/
/* Helper functions */
static inline volatile struct a2232memory *a2232mem(unsigned int board)
{
return (volatile struct a2232memory *)ZTWO_VADDR(zd_a2232[board]->resource.start);
}
static inline volatile struct a2232status *a2232stat(unsigned int board,
unsigned int portonboard)
{
volatile struct a2232memory *mem = a2232mem(board);
return &(mem->Status[portonboard]);
}
static inline void a2232_receive_char(struct a2232_port *port, int ch, int err)
{
/* Mostly stolen from other drivers.
Maybe one could implement a more efficient version by not only
transferring one character at a time.
*/
struct tty_struct *tty = port->gs.port.tty;
#if 0
switch(err) {
case TTY_BREAK:
break;
case TTY_PARITY:
break;
case TTY_OVERRUN:
break;
case TTY_FRAME:
break;
}
#endif
[PATCH] TTY layer buffering revamp The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
tty_insert_flip_char(tty, ch, err);
tty_flip_buffer_push(tty);
}
/***************************** Functions ****************************/
/*** BEGIN OF REAL_DRIVER FUNCTIONS ***/
static void a2232_disable_tx_interrupts(void *ptr)
{
struct a2232_port *port;
volatile struct a2232status *stat;
unsigned long flags;
port = ptr;
stat = a2232stat(port->which_a2232, port->which_port_on_a2232);
stat->OutDisable = -1;
/* Does this here really have to be? */
local_irq_save(flags);
port->gs.port.flags &= ~GS_TX_INTEN;
local_irq_restore(flags);
}
static void a2232_enable_tx_interrupts(void *ptr)
{
struct a2232_port *port;
volatile struct a2232status *stat;
unsigned long flags;
port = ptr;
stat = a2232stat(port->which_a2232, port->which_port_on_a2232);
stat->OutDisable = 0;
/* Does this here really have to be? */
local_irq_save(flags);
port->gs.port.flags |= GS_TX_INTEN;
local_irq_restore(flags);
}
static void a2232_disable_rx_interrupts(void *ptr)
{
struct a2232_port *port;
port = ptr;
port->disable_rx = -1;
}
static void a2232_enable_rx_interrupts(void *ptr)
{
struct a2232_port *port;
port = ptr;
port->disable_rx = 0;
}
static int a2232_get_CD(void *ptr)
{
return ((struct a2232_port *) ptr)->cd_status;
}
static void a2232_shutdown_port(void *ptr)
{
struct a2232_port *port;
volatile struct a2232status *stat;
unsigned long flags;
port = ptr;
stat = a2232stat(port->which_a2232, port->which_port_on_a2232);
local_irq_save(flags);
port->gs.port.flags &= ~GS_ACTIVE;
if (port->gs.port.tty && port->gs.port.tty->termios->c_cflag & HUPCL) {
/* Set DTR and RTS to Low, flush output.
The NetBSD driver "msc.c" does it this way. */
stat->Command = ( (stat->Command & ~A2232CMD_CMask) |
A2232CMD_Close );
stat->OutFlush = -1;
stat->Setup = -1;
}
local_irq_restore(flags);
/* After analyzing control flow, I think a2232_shutdown_port
is actually the last call from the system when at application
level someone issues a "echo Hello >>/dev/ttyY0".
Therefore I think the MOD_DEC_USE_COUNT should be here and
not in "a2232_close()". See the comment in "sx.c", too.
If you run into problems, compile this driver into the
kernel instead of compiling it as a module. */
}
static int a2232_set_real_termios(void *ptr)
{
unsigned int cflag, baud, chsize, stopb, parity, softflow;
int rate;
int a2232_param, a2232_cmd;
unsigned long flags;
unsigned int i;
struct a2232_port *port = ptr;
volatile struct a2232status *status;
volatile struct a2232memory *mem;
if (!port->gs.port.tty || !port->gs.port.tty->termios) return 0;
status = a2232stat(port->which_a2232, port->which_port_on_a2232);
mem = a2232mem(port->which_a2232);
a2232_param = a2232_cmd = 0;
// get baud rate
baud = port->gs.baud;
if (baud == 0) {
/* speed == 0 -> drop DTR, do nothing else */
local_irq_save(flags);
// Clear DTR (and RTS... mhhh).
status->Command = ( (status->Command & ~A2232CMD_CMask) |
A2232CMD_Close );
status->OutFlush = -1;
status->Setup = -1;
local_irq_restore(flags);
return 0;
}
rate = A2232_BAUD_TABLE_NOAVAIL;
for (i=0; i < A2232_BAUD_TABLE_NUM_RATES * 3; i += 3){
if (a2232_baud_table[i] == baud){
if (mem->Common.Crystal == A2232_TURBO) rate = a2232_baud_table[i+2];
else rate = a2232_baud_table[i+1];
}
}
if (rate == A2232_BAUD_TABLE_NOAVAIL){
printk("a2232: Board %d Port %d unsupported baud rate: %d baud. Using another.\n",port->which_a2232,port->which_port_on_a2232,baud);
// This is useful for both (turbo or normal) Crystal versions.
rate = A2232PARAM_B9600;
}
a2232_param |= rate;
cflag = port->gs.port.tty->termios->c_cflag;
// get character size
chsize = cflag & CSIZE;
switch (chsize){
case CS8: a2232_param |= A2232PARAM_8Bit; break;
case CS7: a2232_param |= A2232PARAM_7Bit; break;
case CS6: a2232_param |= A2232PARAM_6Bit; break;
case CS5: a2232_param |= A2232PARAM_5Bit; break;
default: printk("a2232: Board %d Port %d unsupported character size: %d. Using 8 data bits.\n",
port->which_a2232,port->which_port_on_a2232,chsize);
a2232_param |= A2232PARAM_8Bit; break;
}
// get number of stop bits
stopb = cflag & CSTOPB;
if (stopb){ // two stop bits instead of one
printk("a2232: Board %d Port %d 2 stop bits unsupported. Using 1 stop bit.\n",
port->which_a2232,port->which_port_on_a2232);
}
// Warn if RTS/CTS not wanted
if (!(cflag & CRTSCTS)){
#ifndef A2232_SUPPRESS_RTSCTS_WARNING
printk("a2232: Board %d Port %d cannot switch off firmware-implemented RTS/CTS hardware flow control.\n",
port->which_a2232,port->which_port_on_a2232);
#endif
}
/* I think this is correct.
However, IXOFF means _input_ flow control and I wonder
if one should care about IXON _output_ flow control,
too. If this makes problems, one should turn the A2232
firmware XON/XOFF "SoftFlow" flow control off and use
the conventional way of inserting START/STOP characters
by hand in throttle()/unthrottle().
*/
softflow = !!( port->gs.port.tty->termios->c_iflag & IXOFF );
// get Parity (Enabled/Disabled? If Enabled, Odd or Even?)
parity = cflag & (PARENB | PARODD);
if (parity & PARENB){
if (parity & PARODD){
a2232_cmd |= A2232CMD_OddParity;
}
else{
a2232_cmd |= A2232CMD_EvenParity;
}
}
else a2232_cmd |= A2232CMD_NoParity;
/* Hmm. Maybe an own a2232_port structure
member would be cleaner? */
if (cflag & CLOCAL)
port->gs.port.flags &= ~ASYNC_CHECK_CD;
else
port->gs.port.flags |= ASYNC_CHECK_CD;
/* Now we have all parameters and can go to set them: */
local_irq_save(flags);
status->Param = a2232_param | A2232PARAM_RcvBaud;
status->Command = a2232_cmd | A2232CMD_Open | A2232CMD_Enable;
status->SoftFlow = softflow;
status->OutDisable = 0;
status->Setup = -1;
local_irq_restore(flags);
return 0;
}
static int a2232_chars_in_buffer(void *ptr)
{
struct a2232_port *port;
volatile struct a2232status *status;
unsigned char ret; /* we need modulo-256 arithmetics */
port = ptr;
status = a2232stat(port->which_a2232, port->which_port_on_a2232);
#if A2232_IOBUFLEN != 256
#error "Re-Implement a2232_chars_in_buffer()!"
#endif
ret = (status->OutHead - status->OutTail);
return ret;
}
static void a2232_close(void *ptr)
{
a2232_disable_tx_interrupts(ptr);
a2232_disable_rx_interrupts(ptr);
/* see the comment in a2232_shutdown_port above. */
}
static void a2232_hungup(void *ptr)
{
a2232_close(ptr);
}
/*** END OF REAL_DRIVER FUNCTIONS ***/
/*** BEGIN FUNCTIONS EXPECTED BY TTY DRIVER STRUCTS ***/
static int a2232_ioctl( struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
return -ENOIOCTLCMD;
}
static void a2232_throttle(struct tty_struct *tty)
{
/* Throttle: System cannot take another chars: Drop RTS or
send the STOP char or whatever.
The A2232 firmware does RTS/CTS anyway, and XON/XOFF
if switched on. So the only thing we can do at this
layer here is not taking any characters out of the
A2232 buffer any more. */
struct a2232_port *port = (struct a2232_port *) tty->driver_data;
port->throttle_input = -1;
}
static void a2232_unthrottle(struct tty_struct *tty)
{
/* Unthrottle: dual to "throttle()" above. */
struct a2232_port *port = (struct a2232_port *) tty->driver_data;
port->throttle_input = 0;
}
static int a2232_open(struct tty_struct * tty, struct file * filp)
{
/* More or less stolen from other drivers. */
int line;
int retval;
struct a2232_port *port;
line = tty->index;
port = &a2232_ports[line];
tty->driver_data = port;
port->gs.port.tty = tty;
port->gs.port.count++;
retval = gs_init_port(&port->gs);
if (retval) {
port->gs.port.count--;
return retval;
}
port->gs.port.flags |= GS_ACTIVE;
retval = gs_block_til_ready(port, filp);
if (retval) {
port->gs.port.count--;
return retval;
}
a2232_enable_rx_interrupts(port);
return 0;
}
/*** END OF FUNCTIONS EXPECTED BY TTY DRIVER STRUCTS ***/
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
static irqreturn_t a2232_vbl_inter(int irq, void *data)
{
#if A2232_IOBUFLEN != 256
#error "Re-Implement a2232_vbl_inter()!"
#endif
struct a2232_port *port;
volatile struct a2232memory *mem;
volatile struct a2232status *status;
unsigned char newhead;
unsigned char bufpos; /* Must be unsigned char. We need the modulo-256 arithmetics */
unsigned char ncd, ocd, ccd; /* names consistent with the NetBSD driver */
volatile u_char *ibuf, *cbuf, *obuf;
int ch, err, n, p;
for (n = 0; n < nr_a2232; n++){ /* for every completely initialized A2232 board */
mem = a2232mem(n);
for (p = 0; p < NUMLINES; p++){ /* for every port on this board */
err = 0;
port = &a2232_ports[n*NUMLINES+p];
if ( port->gs.port.flags & GS_ACTIVE ){ /* if the port is used */
status = a2232stat(n,p);
if (!port->disable_rx && !port->throttle_input){ /* If input is not disabled */
newhead = status->InHead; /* 65EC02 write pointer */
bufpos = status->InTail;
/* check for input for this port */
if (newhead != bufpos) {
/* buffer for input chars/events */
ibuf = mem->InBuf[p];
/* data types of bytes in ibuf */
cbuf = mem->InCtl[p];
/* do for all chars */
while (bufpos != newhead) {
/* which type of input data? */
switch (cbuf[bufpos]) {
/* switch on input event (CD, BREAK, etc.) */
case A2232INCTL_EVENT:
switch (ibuf[bufpos++]) {
case A2232EVENT_Break:
/* TODO: Handle BREAK signal */
break;
/* A2232EVENT_CarrierOn and A2232EVENT_CarrierOff are
handled in a separate queue and should not occur here. */
case A2232EVENT_Sync:
printk("A2232: 65EC02 software sent SYNC event, don't know what to do. Ignoring.");
break;
default:
printk("A2232: 65EC02 software broken, unknown event type %d occurred.\n",ibuf[bufpos-1]);
} /* event type switch */
break;
case A2232INCTL_CHAR:
/* Receive incoming char */
a2232_receive_char(port, ibuf[bufpos], err);
bufpos++;
break;
default:
printk("A2232: 65EC02 software broken, unknown data type %d occurred.\n",cbuf[bufpos]);
bufpos++;
} /* switch on input data type */
} /* while there's something in the buffer */
status->InTail = bufpos; /* tell 65EC02 what we've read */
} /* if there was something in the buffer */
} /* If input is not disabled */
/* Now check if there's something to output */
obuf = mem->OutBuf[p];
bufpos = status->OutHead;
while ( (port->gs.xmit_cnt > 0) &&
(!port->gs.port.tty->stopped) &&
(!port->gs.port.tty->hw_stopped) ){ /* While there are chars to transmit */
if (((bufpos+1) & A2232_IOBUFLENMASK) != status->OutTail) { /* If the A2232 buffer is not full */
ch = port->gs.xmit_buf[port->gs.xmit_tail]; /* get the next char to transmit */
port->gs.xmit_tail = (port->gs.xmit_tail+1) & (SERIAL_XMIT_SIZE-1); /* modulo-addition for the gs.xmit_buf ring-buffer */
obuf[bufpos++] = ch; /* put it into the A2232 buffer */
port->gs.xmit_cnt--;
}
else{ /* If A2232 the buffer is full */
break; /* simply stop filling it. */
}
}
status->OutHead = bufpos;
/* WakeUp if output buffer runs low */
if ((port->gs.xmit_cnt <= port->gs.wakeup_chars) && port->gs.port.tty) {
tty_wakeup(port->gs.port.tty);
}
} // if the port is used
} // for every port on the board
/* Now check the CD message queue */
newhead = mem->Common.CDHead;
bufpos = mem->Common.CDTail;
if (newhead != bufpos){ /* There are CD events in queue */
ocd = mem->Common.CDStatus; /* get old status bits */
while (newhead != bufpos){ /* read all events */
ncd = mem->CDBuf[bufpos++]; /* get one event */
ccd = ncd ^ ocd; /* mask of changed lines */
ocd = ncd; /* save new status bits */
for(p=0; p < NUMLINES; p++){ /* for all ports */
if (ccd & 1){ /* this one changed */
struct a2232_port *port = &a2232_ports[n*7+p];
port->cd_status = !(ncd & 1); /* ncd&1 <=> CD is now off */
if (!(port->gs.port.flags & ASYNC_CHECK_CD))
; /* Don't report DCD changes */
else if (port->cd_status) { // if DCD on: DCD went UP!
/* Are we blocking in open?*/
wake_up_interruptible(&port->gs.port.open_wait);
}
else { // if DCD off: DCD went DOWN!
if (port->gs.port.tty)
tty_hangup (port->gs.port.tty);
}
} // if CD changed for this port
ccd >>= 1;
ncd >>= 1; /* Shift bits for next line */
} // for every port
} // while CD events in queue
mem->Common.CDStatus = ocd; /* save new status */
mem->Common.CDTail = bufpos; /* remove events */
} // if events in CD queue
} // for every completely initialized A2232 board
return IRQ_HANDLED;
}
static void a2232_init_portstructs(void)
{
struct a2232_port *port;
int i;
for (i = 0; i < MAX_A2232_BOARDS*NUMLINES; i++) {
port = a2232_ports + i;
port->which_a2232 = i/NUMLINES;
port->which_port_on_a2232 = i%NUMLINES;
port->disable_rx = port->throttle_input = port->cd_status = 0;
port->gs.magic = A2232_MAGIC;
port->gs.close_delay = HZ/2;
port->gs.closing_wait = 30 * HZ;
port->gs.rd = &a2232_real_driver;
#ifdef NEW_WRITE_LOCKING
mutex_init(&(port->gs.port_write_mutex));
#endif
init_waitqueue_head(&port->gs.port.open_wait);
init_waitqueue_head(&port->gs.port.close_wait);
}
}
static const struct tty_operations a2232_ops = {
.open = a2232_open,
.close = gs_close,
.write = gs_write,
.put_char = gs_put_char,
.flush_chars = gs_flush_chars,
.write_room = gs_write_room,
.chars_in_buffer = gs_chars_in_buffer,
.flush_buffer = gs_flush_buffer,
.ioctl = a2232_ioctl,
.throttle = a2232_throttle,
.unthrottle = a2232_unthrottle,
.set_termios = gs_set_termios,
.stop = gs_stop,
.start = gs_start,
.hangup = gs_hangup,
};
static int a2232_init_drivers(void)
{
int error;
a2232_driver = alloc_tty_driver(NUMLINES * nr_a2232);
if (!a2232_driver)
return -ENOMEM;
a2232_driver->owner = THIS_MODULE;
a2232_driver->driver_name = "commodore_a2232";
a2232_driver->name = "ttyY";
a2232_driver->major = A2232_NORMAL_MAJOR;
a2232_driver->type = TTY_DRIVER_TYPE_SERIAL;
a2232_driver->subtype = SERIAL_TYPE_NORMAL;
a2232_driver->init_termios = tty_std_termios;
a2232_driver->init_termios.c_cflag =
B9600 | CS8 | CREAD | HUPCL | CLOCAL;
a2232_driver->init_termios.c_ispeed = 9600;
a2232_driver->init_termios.c_ospeed = 9600;
a2232_driver->flags = TTY_DRIVER_REAL_RAW;
tty_set_operations(a2232_driver, &a2232_ops);
if ((error = tty_register_driver(a2232_driver))) {
printk(KERN_ERR "A2232: Couldn't register A2232 driver, error = %d\n",
error);
put_tty_driver(a2232_driver);
return 1;
}
return 0;
}
static int __init a2232board_init(void)
{
struct zorro_dev *z;
unsigned int boardaddr;
int bcount;
short start;
u_char *from;
volatile u_char *to;
volatile struct a2232memory *mem;
#ifdef CONFIG_SMP
return -ENODEV; /* This driver is not SMP aware. Is there an SMP ZorroII-bus-machine? */
#endif
if (!MACH_IS_AMIGA){
return -ENODEV;
}
printk("Commodore A2232 driver initializing.\n"); /* Say that we're alive. */
z = NULL;
nr_a2232 = 0;
while ( (z = zorro_find_device(ZORRO_WILDCARD, z)) ){
if ( (z->id != ZORRO_PROD_CBM_A2232_PROTOTYPE) &&
(z->id != ZORRO_PROD_CBM_A2232) ){
continue; // The board found was no A2232
}
if (!zorro_request_device(z,"A2232 driver"))
continue;
printk("Commodore A2232 found (#%d).\n",nr_a2232);
zd_a2232[nr_a2232] = z;
boardaddr = ZTWO_VADDR( z->resource.start );
printk("Board is located at address 0x%x, size is 0x%x.\n", boardaddr, (unsigned int) ((z->resource.end+1) - (z->resource.start)));
mem = (volatile struct a2232memory *) boardaddr;
(void) mem->Enable6502Reset; /* copy the code across to the board */
to = (u_char *)mem; from = a2232_65EC02code; bcount = sizeof(a2232_65EC02code) - 2;
start = *(short *)from;
from += sizeof(start);
to += start;
while(bcount--) *to++ = *from++;
printk("65EC02 software uploaded to the A2232 memory.\n");
mem->Common.Crystal = A2232_UNKNOWN; /* use automatic speed check */
/* start 6502 running */
(void) mem->ResetBoard;
printk("A2232's 65EC02 CPU up and running.\n");
/* wait until speed detector has finished */
for (bcount = 0; bcount < 2000; bcount++) {
udelay(1000);
if (mem->Common.Crystal)
break;
}
printk((mem->Common.Crystal?"A2232 oscillator crystal detected by 65EC02 software: ":"65EC02 software could not determine A2232 oscillator crystal: "));
switch (mem->Common.Crystal){
case A2232_UNKNOWN:
printk("Unknown crystal.\n");
break;
case A2232_NORMAL:
printk ("Normal crystal.\n");
break;
case A2232_TURBO:
printk ("Turbo crystal.\n");
break;
default:
printk ("0x%x. Huh?\n",mem->Common.Crystal);
}
nr_a2232++;
}
printk("Total: %d A2232 boards initialized.\n", nr_a2232); /* Some status report if no card was found */
a2232_init_portstructs();
/*
a2232_init_drivers also registers the drivers. Must be here because all boards
have to be detected first.
*/
if (a2232_init_drivers()) return -ENODEV; // maybe we should use a different -Exxx?
request_irq(IRQ_AMIGA_VERTB, a2232_vbl_inter, 0, "A2232 serial VBL", a2232_driver_ID);
return 0;
}
static void __exit a2232board_exit(void)
{
int i;
for (i = 0; i < nr_a2232; i++) {
zorro_release_device(zd_a2232[i]);
}
tty_unregister_driver(a2232_driver);
put_tty_driver(a2232_driver);
free_irq(IRQ_AMIGA_VERTB, a2232_driver_ID);
}
module_init(a2232board_init);
module_exit(a2232board_exit);
MODULE_AUTHOR("Enver Haase");
MODULE_DESCRIPTION("Amiga A2232 multi-serial board driver");
MODULE_LICENSE("GPL");