patch-2.2.18 linux/drivers/char/amiga_ser.c

• Lines: 559
• Date: Fri Oct 13 23:57:54 2000
• Orig file: v2.2.17/drivers/char/amiga_ser.c
• Orig date: Thu Jan 1 01:00:00 1970

diff -u --new-file --recursive --exclude-from /usr/src/exclude v2.2.17/drivers/char/amiga_ser.c linux/drivers/char/amiga_ser.c
@@ -0,0 +1,558 @@
+/*
+ * drivers/char/amiga_ser.c: Amiga built-in serial port driver.
+ *
+ * Copyright 1994 Roman Hodek, 1994 Hamish Macdonald
+ *       Based on the Atari MFP driver by Roman Hodek
+ *
+ * Modifications by Matthias Welwarsky <Matthias.Welwarsky@ppp.th-darmstadt.de>
+ * - fixed reentrancy problem in ser_tx_int()
+ * 
+ * 20/02/99 - Jesper Skov: Added mb() calls and KGDB support.
+ * 27/04/96 - Jes Soerensen: Upgraded for Linux-1.3.x.
+ * 02/09/96 - Jes Soerensen: Moved the {request,free}_irq call for
+ *            AMIGA_VERTB interrupts into the init/deinit funtions as
+ *            there is no reason to service the ser_vbl_int when the
+ *            serial port is not in use.
+ * 30/04/96 - Geert Uytterhoeven: Added incoming BREAK detection
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ */
+
+
+/*
+ * This file implements the driver for the Amiga built-in serial port.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/termios.h>
+#include <linux/interrupt.h>
+#include <linux/m68kserial.h>
+#include <linux/linkage.h>
+
+#include <asm/setup.h>
+#include <asm/amigahw.h>
+#include <asm/amigaints.h>
+#include <asm/traps.h>
+#include <asm/irq.h>
+#include <asm/atomic.h>
+
+/* some serial hardware definitions */
+#define SDR_OVRUN   (1<<15)
+#define SDR_RBF     (1<<14)
+#define SDR_TBE     (1<<13)
+#define SDR_TSRE    (1<<12)
+
+#define AC_SETCLR   (1<<15)
+#define AC_UARTBRK  (1<<11)
+
+#define SER_DTR     (1<<7)
+#define SER_RTS     (1<<6)
+#define SER_DCD     (1<<5)
+#define SER_CTS     (1<<4)
+#define SER_DSR     (1<<3)
+
+/***************************** Prototypes *****************************/
+
+static void ser_rx_int( int irq, void *data, struct pt_regs *fp);
+static void ser_tx_int( int irq, void *data, struct pt_regs *fp);
+static void ser_vbl_int( int irq, void *data, struct pt_regs *fp);
+static void ser_init( struct m68k_async_struct *info );
+static void ser_deinit( struct m68k_async_struct *info, int leave_dtr );
+static void ser_enab_tx_int( struct m68k_async_struct *info, int enab_flag );
+static int  ser_check_custom_divisor (struct m68k_async_struct *info,
+				      int baud_base, int divisor);
+static void ser_change_speed( struct m68k_async_struct *info );
+static void ser_throttle( struct m68k_async_struct *info, int status );
+static void ser_set_break( struct m68k_async_struct *info, int break_flag );
+static void ser_get_serial_info( struct m68k_async_struct *info,
+				struct serial_struct *retinfo );
+static unsigned int ser_get_modem_info( struct m68k_async_struct *info );
+static int ser_set_modem_info( struct m68k_async_struct *info, int new_dtr,
+			      int new_rts );
+static void ser_stop_receive( struct m68k_async_struct *info );
+static int ser_trans_empty( struct m68k_async_struct *info );
+
+/************************* End of Prototypes **************************/
+
+
+
+/* SERIALSWITCH structure for the Amiga serial port
+ */
+
+static SERIALSWITCH amiga_ser_switch = {
+    ser_init, ser_deinit, ser_enab_tx_int,
+    ser_check_custom_divisor, ser_change_speed,
+    ser_throttle, ser_set_break,
+    ser_get_serial_info, ser_get_modem_info,
+    ser_set_modem_info, NULL, ser_stop_receive, ser_trans_empty, NULL
+};
+
+/* Standard speeds table */
+static int baud_table[19] = {
+    /* B0     */ 0,
+    /* B50    */ 50,
+    /* B75    */ 75,
+    /* B110   */ 110,
+    /* B134   */ 134,
+    /* B150   */ 150,
+    /* B200   */ 200,
+    /* B300   */ 300,
+    /* B600   */ 600,
+    /* B1200  */ 1200,
+    /* B1800  */ 1800,
+    /* B2400  */ 2400,
+    /* B4800  */ 4800,
+    /* B9600  */ 9600,
+    /* B19200 */ 19200,
+    /* B38400 */ 38400,
+    /* B57600 */ 57600,
+    /* B115200*/ 115200,
+    /* B230400*/ 230400
+};
+	
+static __inline__ void ser_DTRoff(void)
+{
+    ciab.pra |= SER_DTR; /* active low */
+}
+
+static __inline__ void ser_DTRon(void)
+{
+    ciab.pra &= ~SER_DTR; /* active low */
+}
+
+static __inline__ void ser_RTSoff(void)
+{
+    ciab.pra |= SER_RTS; /* active low */
+}
+
+static __inline__ void ser_RTSon(void)
+{
+    ciab.pra &= ~SER_RTS; /* active low */
+}
+
+static int line; /* the serial line assigned by register_serial() */
+/* use this value in isr's to get rid of the data pointer in the future */
+/* This variable holds the current state of the DCD/CTS bits */
+static unsigned char current_ctl_bits;
+
+static __inline__ void check_modem_status(struct m68k_async_struct *info)
+{
+	unsigned char bits;
+
+	if (!(info->flags & ASYNC_INITIALIZED))
+		return;
+
+	bits = ciab.pra & (SER_DCD | SER_CTS);
+
+	if (bits ^ current_ctl_bits) {
+		if ((bits ^ current_ctl_bits) & SER_DCD) {
+			rs_dcd_changed(info, !(bits & SER_DCD));
+		}
+
+		if ((bits ^ current_ctl_bits) & SER_CTS)
+			rs_check_cts(info, !(bits & SER_CTS));
+	}
+	current_ctl_bits = bits;
+}
+
+static struct m68k_async_struct *amiga_info;
+
+int amiga_serinit( void )
+{	
+	unsigned long flags;
+	struct serial_struct req;
+	struct m68k_async_struct *info;
+	
+	if (!MACH_IS_AMIGA || !AMIGAHW_PRESENT(AMI_SERIAL))
+		return -ENODEV;
+
+	req.line = -1; /* first free ttyS? device */
+	req.type = SER_AMIGA;
+	req.port = (int) &custom.serdatr; /* dummy value */
+	if ((line = m68k_register_serial( &req )) < 0) {
+		printk( "Cannot register built-in serial port: no free device\n" );
+		return -EBUSY;
+	}
+    info = &rs_table[line];
+	
+    save_flags (flags);
+    cli();
+
+    /* set ISRs, and then disable the rx interrupts */
+    request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", info);
+    request_irq(IRQ_AMIGA_RBF, ser_rx_int, 0, "serial RX", info);
+
+    amiga_info = info;
+
+    /* turn off Rx and Tx interrupts */
+    custom.intena = IF_RBF | IF_TBE;
+
+    /* clear any pending interrupt */
+    custom.intreq = IF_RBF | IF_TBE;
+    restore_flags (flags);
+
+    /*
+     * set the appropriate directions for the modem control flags,
+     * and clear RTS and DTR
+     */
+    ciab.ddra |= (SER_DTR | SER_RTS);   /* outputs */
+    ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR);  /* inputs */
+    
+    info->sw   = &amiga_ser_switch;
+
+#ifdef CONFIG_KGDB
+    /* turn Rx interrupts on for GDB */
+    custom.intena = IF_SETCLR | IF_RBF;
+    ser_RTSon();
+#endif
+
+    return 0;
+}
+
+static void ser_rx_int(int irq, void *data, struct pt_regs *fp)
+{
+#ifdef CONFIG_KGDB
+      extern void breakpoint (void);
+      int ch;
+
+      ch = custom.serdatr;
+      mb();
+
+      custom.intreq = IF_RBF;
+
+      /* Break signal from GDB? */
+      if (0x03 == (ch & 0xff)) {
+	      /* FIXME: This way of doing a breakpoint sucks
+		 big time. I will fix it later. */
+	      breakpoint ();
+      }
+#else
+      struct m68k_async_struct *info = data;
+      int ch, err;
+
+      ch = custom.serdatr;
+      mb();
+
+      custom.intreq = IF_RBF;
+
+      if ((ch & 0x1ff) == 0)
+	  err = TTY_BREAK;
+      else if (ch & SDR_OVRUN)
+	  err = TTY_OVERRUN;
+      else
+	  err = 0;
+      rs_receive_char(info, ch & 0xff, err);
+#endif
+}
+
+static void ser_tx_int( int irq, void *data, struct pt_regs *fp)
+{
+#ifndef CONFIG_KGDB
+      struct m68k_async_struct *info = data;
+      int ch;
+
+      if (custom.serdatr & SDR_TBE) {
+	   if ((ch = rs_get_tx_char(info)) >= 0)
+	        /* write next char */
+	        custom.serdat = ch | 0x100;
+	   if (ch == -1 || rs_no_more_tx( info ))
+	        /* disable tx interrupts */
+	        custom.intena = IF_TBE;
+      }
+#endif
+}
+
+
+static void ser_vbl_int( int irq, void *data, struct pt_regs *fp)
+{
+	struct m68k_async_struct *info = data;
+
+	check_modem_status(info);
+}
+
+
+static void ser_init( struct m68k_async_struct *info )
+{	
+#ifndef CONFIG_KGDB
+	request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0,
+		    "serial status", amiga_info);
+
+	/* enable both Rx and Tx interrupts */
+	custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
+
+	/* turn on DTR and RTS */
+	ser_DTRon();
+	ser_RTSon();
+
+	/* remember current state of the DCD and CTS bits */
+	current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS);
+
+	MOD_INC_USE_COUNT;
+#endif
+}
+
+
+static void ser_enab_tx_int (struct m68k_async_struct *info, int enab_flag)
+{
+#ifndef CONFIG_KGDB
+    if (enab_flag) {
+        unsigned long flags;
+	save_flags(flags);
+	cli();
+	custom.intena = IF_SETCLR | IF_TBE;
+	mb();
+	/* set a pending Tx Interrupt, transmitter should restart now */
+	custom.intreq = IF_SETCLR | IF_TBE;
+	mb();
+	restore_flags(flags);
+    } else {
+	/* disable Tx interrupt and remove any pending interrupts */
+        custom.intena = IF_TBE;
+	custom.intreq = IF_TBE;
+    }
+#endif
+}
+
+
+static void ser_deinit( struct m68k_async_struct *info, int leave_dtr )
+{
+#ifndef CONFIG_KGDB
+    /* disable Rx and Tx interrupt */
+    custom.intena = IF_RBF | IF_TBE;
+    mb();
+
+    /* wait for last byte to be completely shifted out */
+    while( !(custom.serdatr & SDR_TSRE) )
+	barrier();
+
+    /* drop RTS and DTR if required */
+    ser_RTSoff();
+    if (!leave_dtr)
+	ser_DTRoff();
+
+    free_irq(IRQ_AMIGA_VERTB, amiga_info);
+    MOD_DEC_USE_COUNT;
+#endif
+}
+
+
+static int ser_check_custom_divisor (struct m68k_async_struct *info,
+				     int baud_base, int divisor)
+{
+    /* allow any divisor */
+    return 0;
+}
+
+
+static void ser_change_speed( struct m68k_async_struct *info )
+{
+#ifndef CONFIG_KGDB
+    unsigned	cflag, baud, chsize, stopb, parity, aflags;
+    unsigned	div = 0;
+    int realbaud;
+
+    if (!info->tty || !info->tty->termios) return;
+
+    cflag  = info->tty->termios->c_cflag;
+    baud   = cflag & CBAUD;
+    chsize = cflag & CSIZE;
+    stopb  = cflag & CSTOPB;
+    parity = cflag & (PARENB | PARODD);
+    aflags = info->flags & ASYNC_SPD_MASK;
+
+    if (cflag & CRTSCTS)
+	info->flags |= ASYNC_CTS_FLOW;
+    else
+	info->flags &= ~ASYNC_CTS_FLOW;
+    if (cflag & CLOCAL)
+	info->flags &= ~ASYNC_CHECK_CD;
+    else
+	info->flags |= ASYNC_CHECK_CD;
+
+    if (baud & CBAUDEX)
+	baud = baud - (B57600 - B38400 - 1);
+
+
+    if (baud == 15) {
+	    switch (aflags) {
+	    case ASYNC_SPD_HI:
+		    baud += 1;
+		    break;
+	    case ASYNC_SPD_VHI:
+		    baud += 2;
+		    break;
+	    case ASYNC_SPD_SHI:
+		    baud += 3;
+		    break;
+	    case ASYNC_SPD_WARP:
+		    baud += 4;
+		    break;
+	    case ASYNC_SPD_CUST:
+		    div = info->custom_divisor;
+		    break;
+	    }
+    }
+    if (!div){
+	/* Maximum speed is 230400 :-) */
+	if (baud > 18) baud = 18;
+	realbaud = baud_table[baud];
+	if (realbaud)
+	    div = (amiga_colorclock+realbaud/2)/realbaud - 1;
+    }
+
+    if (div) {
+	    /* turn on DTR */
+	    ser_DTRon();
+    } else {
+	    /* speed == 0 -> drop DTR */
+	    ser_DTRoff();
+	    return;
+    }
+
+    /* setup the serial port period register */
+    custom.serper = div;
+#endif
+}
+
+
+static void ser_throttle( struct m68k_async_struct *info, int status )
+{
+#ifndef CONFIG_KGDB
+    if (status)
+	ser_RTSoff();
+    else
+	ser_RTSon();
+#endif
+}
+
+
+static void ser_set_break( struct m68k_async_struct *info, int break_flag )
+{
+#ifndef CONFIG_KGDB
+    if (break_flag)
+	custom.adkcon = AC_SETCLR | AC_UARTBRK;
+    else
+	custom.adkcon = AC_UARTBRK;
+#endif
+}
+
+
+static void ser_get_serial_info( struct m68k_async_struct *info,
+				 struct serial_struct *retinfo )
+{
+    retinfo->baud_base = amiga_colorclock;
+    retinfo->custom_divisor = info->custom_divisor;
+}
+
+
+static unsigned int ser_get_modem_info( struct m68k_async_struct *info )
+{
+    unsigned int minfo = ciab.pra;
+
+    return(
+	   ((minfo & SER_DTR) ? 0 : TIOCM_DTR) |
+	   ((minfo & SER_RTS) ? 0 : TIOCM_RTS) |
+	   ((minfo & SER_DCD) ? 0 : TIOCM_CAR) |
+	   ((minfo & SER_CTS) ? 0 : TIOCM_CTS) |
+	   ((minfo & SER_DSR) ? 0 : TIOCM_DSR) |
+	   /* TICM_RNG */ 0
+	   );
+}
+
+
+static int ser_set_modem_info( struct m68k_async_struct *info,
+			       int new_dtr, int new_rts )
+{
+#ifndef CONFIG_KGDB
+    if (new_dtr == 0)
+	ser_DTRoff();
+    else if (new_dtr == 1)
+	ser_DTRon();
+
+    if (new_rts == 0)
+	ser_RTSoff();
+    else if (new_rts == 1)
+	ser_RTSon();
+
+    return 0;
+#endif
+}
+
+static void ser_stop_receive( struct m68k_async_struct *info )
+{
+#ifndef CONFIG_KGDB
+	/* disable receive interrupts */
+	custom.intena = IF_RBF;
+	/* clear any pending receive interrupt */
+	custom.intreq = IF_RBF;
+#endif
+}
+
+static int ser_trans_empty( struct m68k_async_struct *info )
+{
+       return (custom.serdatr & SDR_TSRE);
+}
+
+#ifdef CONFIG_KGDB
+int amiga_ser_out( unsigned char c )
+{
+	custom.serdat = c | 0x100;
+	mb();
+	while (!(custom.serdatr & 0x2000))
+		barrier();
+	return 1;
+}
+
+unsigned char amiga_ser_in( void )
+{
+	unsigned char c;
+
+	/* XXX: is that ok?? derived from amiga_ser.c... */
+	while( !(custom.intreqr & IF_RBF) )
+		barrier();
+	c = custom.serdatr;
+	/* clear the interrupt, so that another character can be read */
+	custom.intreq = IF_RBF;
+	return c;
+}
+#endif
+
+#ifdef MODULE
+int init_module(void)
+{
+	return amiga_serinit();
+}
+
+void cleanup_module(void)
+{
+	m68k_unregister_serial(line);
+	custom.intena = IF_RBF | IF_TBE; /* forbid interrupts */
+	custom.intreq = IF_RBF | IF_TBE; /* clear pending interrupts */
+	mb();
+	free_irq(IRQ_AMIGA_TBE, amiga_info);
+	free_irq(IRQ_AMIGA_RBF, amiga_info);
+}
+#endif
+
+
+/* ------------------------------------
+ * Local variables:
+ * c-indent-level: 4
+ * c-brace-imaginary-offset: 0
+ * c-brace-offset: -4
+ * c-argdecl-indent: 4
+ * c-label-offset: -4
+ * c-continued-statement-offset: 4
+ * c-continued-brace-offset: 0
+ * End:
+ * ------------------------------------
+ */