// SPDX-License-Identifier: GPL-2.0#include <linux/interrupt.h>#include <linux/ioport.h> #include "spk_types.h"#include "speakup.h"#include "spk_priv.h"#include "serialio.h" #include <linux/serial_core.h>/* WARNING:  Do not change this to <linux/serial.h> without testing that * SERIAL_PORT_DFNS does get defined to the appropriate value. */#include <asm/serial.h> #ifndef SERIAL_PORT_DFNS#define SERIAL_PORT_DFNS#endif static void start_serial_interrupt(int irq); static const struct old_serial_port rs_table[] = {	SERIAL_PORT_DFNS}; static const struct old_serial_port *serstate;static int timeouts; static int spk_serial_out(struct spk_synth *in_synth, const char ch);static void spk_serial_send_xchar(struct spk_synth *in_synth, char ch);static void spk_serial_tiocmset(struct spk_synth *in_synth, unsigned int set, unsigned int clear);static unsigned char spk_serial_in(struct spk_synth *in_synth);static unsigned char spk_serial_in_nowait(struct spk_synth *in_synth);static void spk_serial_flush_buffer(struct spk_synth *in_synth);static int spk_serial_wait_for_xmitr(struct spk_synth *in_synth); struct spk_io_ops spk_serial_io_ops = {	.synth_out = spk_serial_out,	.send_xchar = spk_serial_send_xchar,	.tiocmset = spk_serial_tiocmset,	.synth_in = spk_serial_in,	.synth_in_nowait = spk_serial_in_nowait,	.flush_buffer = spk_serial_flush_buffer,	.wait_for_xmitr = spk_serial_wait_for_xmitr,};EXPORT_SYMBOL_GPL(spk_serial_io_ops); const struct old_serial_port *spk_serial_init(int index){	int baud = 9600, quot = 0;	unsigned int cval = 0;	int cflag = CREAD | HUPCL | CLOCAL | B9600 | CS8;	const struct old_serial_port *ser;	int err; 	if (index >= ARRAY_SIZE(rs_table)) {		pr_info("no port info for ttyS%d\n", index);		return NULL;	}	ser = rs_table + index; 	/*	Divisor, byte size and parity */	quot = ser->baud_base / baud;	cval = cflag & (CSIZE | CSTOPB);#if defined(__powerpc__) || defined(__alpha__)	cval >>= 8;#else /* !__powerpc__ && !__alpha__ */	cval >>= 4;#endif /* !__powerpc__ && !__alpha__ */	if (cflag & PARENB)		cval |= UART_LCR_PARITY;	if (!(cflag & PARODD))		cval |= UART_LCR_EPAR;	if (synth_request_region(ser->port, 8)) {		/* try to take it back. */		pr_info("Ports not available, trying to steal them\n");		__release_region(&ioport_resource, ser->port, 8);		err = synth_request_region(ser->port, 8);		if (err) {			pr_warn("Unable to allocate port at %x, errno %i",				ser->port, err);			return NULL;		}	} 	/*	Disable UART interrupts, set DTR and RTS high	 *	and set speed.	 */	outb(cval | UART_LCR_DLAB, ser->port + UART_LCR);	/* set DLAB */	outb(quot & 0xff, ser->port + UART_DLL);	/* LS of divisor */	outb(quot >> 8, ser->port + UART_DLM);		/* MS of divisor */	outb(cval, ser->port + UART_LCR);		/* reset DLAB */ 	/* Turn off Interrupts */	outb(0, ser->port + UART_IER);	outb(UART_MCR_DTR | UART_MCR_RTS, ser->port + UART_MCR); 	/* If we read 0xff from the LSR, there is no UART here. */	if (inb(ser->port + UART_LSR) == 0xff) {		synth_release_region(ser->port, 8);		serstate = NULL;		return NULL;	} 	mdelay(1);	speakup_info.port_tts = ser->port;	serstate = ser; 	start_serial_interrupt(ser->irq); 	return ser;} static irqreturn_t synth_readbuf_handler(int irq, void *dev_id){	unsigned long flags;	int c; 	spin_lock_irqsave(&speakup_info.spinlock, flags);	while (inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR) {		c = inb_p(speakup_info.port_tts + UART_RX);		synth->read_buff_add((u_char)c);	}	spin_unlock_irqrestore(&speakup_info.spinlock, flags);	return IRQ_HANDLED;} static void start_serial_interrupt(int irq){	int rv; 	if (!synth->read_buff_add)		return; 	rv = request_irq(irq, synth_readbuf_handler, IRQF_SHARED,			 "serial", (void *)synth_readbuf_handler); 	if (rv)		pr_err("Unable to request Speakup serial I R Q\n");	/* Set MCR */	outb(UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2,	     speakup_info.port_tts + UART_MCR);	/* Turn on Interrupts */	outb(UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI,	     speakup_info.port_tts + UART_IER);	inb(speakup_info.port_tts + UART_LSR);	inb(speakup_info.port_tts + UART_RX);	inb(speakup_info.port_tts + UART_IIR);	inb(speakup_info.port_tts + UART_MSR);	outb(1, speakup_info.port_tts + UART_FCR);	/* Turn FIFO On */} static void spk_serial_send_xchar(struct spk_synth *synth, char ch){	int timeout = SPK_XMITR_TIMEOUT; 	while (spk_serial_tx_busy()) {		if (!--timeout)			break;		udelay(1);	}	outb(ch, speakup_info.port_tts);} static void spk_serial_tiocmset(struct spk_synth *in_synth, unsigned int set, unsigned int clear){	int old = inb(speakup_info.port_tts + UART_MCR); 	outb((old & ~clear) | set, speakup_info.port_tts + UART_MCR);} int spk_serial_synth_probe(struct spk_synth *synth){	const struct old_serial_port *ser;	int failed = 0; 	if ((synth->ser >= SPK_LO_TTY) && (synth->ser <= SPK_HI_TTY)) {		ser = spk_serial_init(synth->ser);		if (!ser) {			failed = -1;		} else {			outb_p(0, ser->port);			mdelay(1);			outb_p('\r', ser->port);		}	} else {		failed = -1;		pr_warn("ttyS%i is an invalid port\n", synth->ser);	}	if (failed) {		pr_info("%s: not found\n", synth->long_name);		return -ENODEV;	}	pr_info("%s: ttyS%i, Driver Version %s\n",		synth->long_name, synth->ser, synth->version);	synth->alive = 1;	return 0;}EXPORT_SYMBOL_GPL(spk_serial_synth_probe); void spk_stop_serial_interrupt(void){	if (speakup_info.port_tts == 0)		return; 	if (!synth->read_buff_add)		return; 	/* Turn off interrupts */	outb(0, speakup_info.port_tts + UART_IER);	/* Free IRQ */	free_irq(serstate->irq, (void *)synth_readbuf_handler);}EXPORT_SYMBOL_GPL(spk_stop_serial_interrupt); static int spk_serial_wait_for_xmitr(struct spk_synth *in_synth){	int tmout = SPK_XMITR_TIMEOUT; 	if ((in_synth->alive) && (timeouts >= NUM_DISABLE_TIMEOUTS)) {		pr_warn("%s: too many timeouts, deactivating speakup\n",			in_synth->long_name);		in_synth->alive = 0;		/* No synth any more, so nobody will restart TTYs, and we thus		 * need to do it ourselves.  Now that there is no synth we can		 * let application flood anyway		 */		speakup_start_ttys();		timeouts = 0;		return 0;	}	while (spk_serial_tx_busy()) {		if (--tmout == 0) {			pr_warn("%s: timed out (tx busy)\n",				in_synth->long_name);			timeouts++;			return 0;		}		udelay(1);	}	tmout = SPK_CTS_TIMEOUT;	while (!((inb_p(speakup_info.port_tts + UART_MSR)) & UART_MSR_CTS)) {		/* CTS */		if (--tmout == 0) {			timeouts++;			return 0;		}		udelay(1);	}	timeouts = 0;	return 1;} static unsigned char spk_serial_in(struct spk_synth *in_synth){	int tmout = SPK_SERIAL_TIMEOUT; 	while (!(inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR)) {		if (--tmout == 0) {			pr_warn("time out while waiting for input.\n");			return 0xff;		}		udelay(1);	}	return inb_p(speakup_info.port_tts + UART_RX);} static unsigned char spk_serial_in_nowait(struct spk_synth *in_synth){	unsigned char lsr; 	lsr = inb_p(speakup_info.port_tts + UART_LSR);	if (!(lsr & UART_LSR_DR))		return 0;	return inb_p(speakup_info.port_tts + UART_RX);} static void spk_serial_flush_buffer(struct spk_synth *in_synth){	/* TODO: flush the UART 16550 buffer */} static int spk_serial_out(struct spk_synth *in_synth, const char ch){	if (in_synth->alive && spk_serial_wait_for_xmitr(in_synth)) {		outb_p(ch, speakup_info.port_tts);		return 1;	}	return 0;} const char *spk_serial_synth_immediate(struct spk_synth *synth,				       const char *buff){	u_char ch; 	while ((ch = *buff)) {		if (ch == '\n')			ch = synth->procspeech;		if (spk_serial_wait_for_xmitr(synth))			outb(ch, speakup_info.port_tts);		else			return buff;		buff++;	}	return NULL;}EXPORT_SYMBOL_GPL(spk_serial_synth_immediate); void spk_serial_release(struct spk_synth *synth){	spk_stop_serial_interrupt();	if (speakup_info.port_tts == 0)		return;	synth_release_region(speakup_info.port_tts, 8);	speakup_info.port_tts = 0;}EXPORT_SYMBOL_GPL(spk_serial_release);