patch-2.4.0-test7 linux/drivers/char/serial_21285.c

• Lines: 512
• Date: Sun Aug 13 10:04:17 2000
• Orig file: v2.4.0-test6/linux/drivers/char/serial_21285.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.0-test6/linux/drivers/char/serial_21285.c linux/drivers/char/serial_21285.c
@@ -0,0 +1,511 @@
+/*
+ * linux/drivers/char/serial_21285.c
+ *
+ * Driver for the serial port on the 21285 StrongArm-110 core logic chip.
+ *
+ * Based on drivers/char/serial.c
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/major.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/mm.h>
+#include <linux/malloc.h>
+#include <linux/init.h>
+#include <linux/console.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/dec21285.h>
+#include <asm/hardware.h>
+
+#define BAUD_BASE		(mem_fclk_21285/64)
+
+#define SERIAL_21285_NAME	"ttyFB"
+#define SERIAL_21285_MAJOR	204
+#define SERIAL_21285_MINOR	4
+
+#define SERIAL_21285_AUXNAME	"cuafb"
+#define SERIAL_21285_AUXMAJOR	205
+#define SERIAL_21285_AUXMINOR	4
+
+static struct tty_driver rs285_driver, callout_driver;
+static int rs285_refcount;
+static struct tty_struct *rs285_table[1];
+
+static struct termios *rs285_termios[1];
+static struct termios *rs285_termios_locked[1];
+
+static char wbuf[1000], *putp = wbuf, *getp = wbuf, x_char;
+static struct tty_struct *rs285_tty;
+static int rs285_use_count;
+
+static int rs285_write_room(struct tty_struct *tty)
+{
+	return putp >= getp ? (sizeof(wbuf) - (long) putp + (long) getp) : ((long) getp - (long) putp - 1);
+}
+
+static void rs285_rx_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+	if (!rs285_tty) {
+		disable_irq(IRQ_CONRX);
+		return;
+	}
+	while (!(*CSR_UARTFLG & 0x10)) {
+		int ch, flag;
+		ch = *CSR_UARTDR;
+		flag = *CSR_RXSTAT;
+		if (flag & 4)
+			tty_insert_flip_char(rs285_tty, 0, TTY_OVERRUN);
+		if (flag & 2)
+			flag = TTY_PARITY;
+		else if (flag & 1)
+			flag = TTY_FRAME;
+		tty_insert_flip_char(rs285_tty, ch, flag);
+	}
+	tty_flip_buffer_push(rs285_tty);
+}
+
+static void rs285_send_xchar(struct tty_struct *tty, char ch)
+{
+	x_char = ch;
+	enable_irq(IRQ_CONTX);
+}
+
+static void rs285_throttle(struct tty_struct *tty)
+{
+	if (I_IXOFF(tty))
+		rs285_send_xchar(tty, STOP_CHAR(tty));
+}
+
+static void rs285_unthrottle(struct tty_struct *tty)
+{
+	if (I_IXOFF(tty)) {
+		if (x_char)
+			x_char = 0;
+		else
+			rs285_send_xchar(tty, START_CHAR(tty));
+	}
+}
+
+static void rs285_tx_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+	while (!(*CSR_UARTFLG & 0x20)) {
+		if (x_char) {
+			*CSR_UARTDR = x_char;
+			x_char = 0;
+			continue;
+		}
+		if (putp == getp) {
+			disable_irq(IRQ_CONTX);
+			break;
+		}
+		*CSR_UARTDR = *getp;
+		if (++getp >= wbuf + sizeof(wbuf))
+			getp = wbuf;
+	}
+	if (rs285_tty)
+		wake_up_interruptible(&rs285_tty->write_wait);
+}
+
+static inline int rs285_xmit(int ch)
+{
+	if (putp + 1 == getp || (putp + 1 == wbuf + sizeof(wbuf) && getp == wbuf))
+		return 0;
+	*putp = ch;
+	if (++putp >= wbuf + sizeof(wbuf))
+		putp = wbuf;
+	enable_irq(IRQ_CONTX);
+	return 1;
+}
+
+static int rs285_write(struct tty_struct *tty, int from_user,
+		       const u_char * buf, int count)
+{
+	int i;
+
+	if (from_user && verify_area(VERIFY_READ, buf, count))
+		return -EINVAL;
+
+	for (i = 0; i < count; i++) {
+		char ch;
+		if (from_user)
+			__get_user(ch, buf + i);
+		else
+			ch = buf[i];
+		if (!rs285_xmit(ch))
+			break;
+	}
+	return i;
+}
+
+static void rs285_put_char(struct tty_struct *tty, u_char ch)
+{
+	rs285_xmit(ch);
+}
+
+static int rs285_chars_in_buffer(struct tty_struct *tty)
+{
+	return sizeof(wbuf) - rs285_write_room(tty);
+}
+
+static void rs285_flush_buffer(struct tty_struct *tty)
+{
+	disable_irq(IRQ_CONTX);
+	putp = getp = wbuf;
+	if (x_char)
+		enable_irq(IRQ_CONTX);
+}
+
+static inline void rs285_set_cflag(int cflag)
+{
+	int h_lcr, baud, quot;
+
+	switch (cflag & CSIZE) {
+	case CS5:
+		h_lcr = 0x10;
+		break;
+	case CS6:
+		h_lcr = 0x30;
+		break;
+	case CS7:
+		h_lcr = 0x50;
+		break;
+	default: /* CS8 */
+		h_lcr = 0x70;
+		break;
+
+	}
+	if (cflag & CSTOPB)
+		h_lcr |= 0x08;
+	if (cflag & PARENB)
+		h_lcr |= 0x02;
+	if (!(cflag & PARODD))
+		h_lcr |= 0x04;
+
+	switch (cflag & CBAUD) {
+	case B200:	baud = 200;		break;
+	case B300:	baud = 300;		break;
+	case B1200:	baud = 1200;		break;
+	case B1800:	baud = 1800;		break;
+	case B2400:	baud = 2400;		break;
+	case B4800:	baud = 4800;		break;
+	default:
+	case B9600:	baud = 9600;		break;
+	case B19200:	baud = 19200;		break;
+	case B38400:	baud = 38400;		break;
+	case B57600:	baud = 57600;		break;
+	case B115200:	baud = 115200;		break;
+	}
+
+	/*
+	 * The documented expression for selecting the divisor is:
+	 *  BAUD_BASE / baud - 1
+	 * However, typically BAUD_BASE is not divisible by baud, so
+	 * we want to select the divisor that gives us the minimum
+	 * error.  Therefore, we want:
+	 *  int(BAUD_BASE / baud - 0.5) ->
+	 *  int(BAUD_BASE / baud - (baud >> 1) / baud) ->
+	 *  int((BAUD_BASE - (baud >> 1)) / baud)
+	 */
+	quot = (BAUD_BASE - (baud >> 1)) / baud;
+
+	*CSR_UARTCON = 0;
+	*CSR_L_UBRLCR = quot & 0xff;
+	*CSR_M_UBRLCR = (quot >> 8) & 0x0f;
+	*CSR_H_UBRLCR = h_lcr;
+	*CSR_UARTCON = 1;
+}
+
+static void rs285_set_termios(struct tty_struct *tty, struct termios *old)
+{
+	if (old && tty->termios->c_cflag == old->c_cflag)
+		return;
+	rs285_set_cflag(tty->termios->c_cflag);
+}
+
+
+static void rs285_stop(struct tty_struct *tty)
+{
+	disable_irq(IRQ_CONTX);
+}
+
+static void rs285_start(struct tty_struct *tty)
+{
+	enable_irq(IRQ_CONTX);
+}
+
+static void rs285_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+	int orig_jiffies = jiffies;
+	while (*CSR_UARTFLG & 8) {
+		current->state = TASK_INTERRUPTIBLE;
+		schedule_timeout(1);
+		if (signal_pending(current))
+			break;
+		if (timeout && time_after(jiffies, orig_jiffies + timeout))
+			break;
+	}
+	current->state = TASK_RUNNING;
+}
+
+static int rs285_open(struct tty_struct *tty, struct file *filp)
+{
+	int line;
+
+	MOD_INC_USE_COUNT;
+	line = MINOR(tty->device) - tty->driver.minor_start;
+	if (line) {
+		MOD_DEC_USE_COUNT;
+		return -ENODEV;
+	}
+
+	tty->driver_data = NULL;
+	if (!rs285_tty)
+		rs285_tty = tty;
+
+	enable_irq(IRQ_CONRX);
+	rs285_use_count++;
+	return 0;
+}
+
+static void rs285_close(struct tty_struct *tty, struct file *filp)
+{
+	if (!--rs285_use_count) {
+		rs285_wait_until_sent(tty, 0);
+		disable_irq(IRQ_CONRX);
+		disable_irq(IRQ_CONTX);
+		rs285_tty = NULL;
+	}
+	MOD_DEC_USE_COUNT;
+}
+
+static int __init rs285_init(void)
+{
+	int baud = B9600;
+
+	if (machine_is_personal_server())
+		baud = B57600;
+
+	rs285_driver.magic = TTY_DRIVER_MAGIC;
+	rs285_driver.driver_name = "serial_21285";
+	rs285_driver.name = SERIAL_21285_NAME;
+	rs285_driver.major = SERIAL_21285_MAJOR;
+	rs285_driver.minor_start = SERIAL_21285_MINOR;
+	rs285_driver.num = 1;
+	rs285_driver.type = TTY_DRIVER_TYPE_SERIAL;
+	rs285_driver.subtype = SERIAL_TYPE_NORMAL;
+	rs285_driver.init_termios = tty_std_termios;
+	rs285_driver.init_termios.c_cflag = baud | CS8 | CREAD | HUPCL | CLOCAL;
+	rs285_driver.flags = TTY_DRIVER_REAL_RAW;
+	rs285_driver.refcount = &rs285_refcount;
+	rs285_driver.table = rs285_table;
+	rs285_driver.termios = rs285_termios;
+	rs285_driver.termios_locked = rs285_termios_locked;
+
+	rs285_driver.open = rs285_open;
+	rs285_driver.close = rs285_close;
+	rs285_driver.write = rs285_write;
+	rs285_driver.put_char = rs285_put_char;
+	rs285_driver.write_room = rs285_write_room;
+	rs285_driver.chars_in_buffer = rs285_chars_in_buffer;
+	rs285_driver.flush_buffer = rs285_flush_buffer;
+	rs285_driver.throttle = rs285_throttle;
+	rs285_driver.unthrottle = rs285_unthrottle;
+	rs285_driver.send_xchar = rs285_send_xchar;
+	rs285_driver.set_termios = rs285_set_termios;
+	rs285_driver.stop = rs285_stop;
+	rs285_driver.start = rs285_start;
+	rs285_driver.wait_until_sent = rs285_wait_until_sent;
+
+	callout_driver = rs285_driver;
+	callout_driver.name = SERIAL_21285_AUXNAME;
+	callout_driver.major = SERIAL_21285_AUXMAJOR;
+	callout_driver.subtype = SERIAL_TYPE_CALLOUT;
+
+	if (request_irq(IRQ_CONRX, rs285_rx_int, 0, "rs285", NULL))
+		panic("Couldn't get rx irq for rs285");
+
+	if (request_irq(IRQ_CONTX, rs285_tx_int, 0, "rs285", NULL))
+		panic("Couldn't get tx irq for rs285");
+
+	if (tty_register_driver(&rs285_driver))
+		printk(KERN_ERR "Couldn't register 21285 serial driver\n");
+	if (tty_register_driver(&callout_driver))
+		printk(KERN_ERR "Couldn't register 21285 callout driver\n");
+
+	return 0;
+}
+
+static void __exit rs285_fini(void)
+{
+	unsigned long flags;
+	int ret;
+
+	save_flags(flags);
+	cli();
+	ret = tty_unregister_driver(&callout_driver);
+	if (ret)
+		printk(KERN_ERR "Unable to unregister 21285 callout driver "
+			"(%d)\n", ret);
+	ret = tty_unregister_driver(&rs285_driver);
+	if (ret)
+		printk(KERN_ERR "Unable to unregister 21285 driver (%d)\n",
+			ret);
+	free_irq(IRQ_CONTX, NULL);
+	free_irq(IRQ_CONRX, NULL);
+	restore_flags(flags);
+}
+
+module_init(rs285_init);
+module_exit(rs285_fini);
+
+#ifdef CONFIG_SERIAL_21285_CONSOLE
+/************** console driver *****************/
+
+static void rs285_console_write(struct console *co, const char *s, u_int count)
+{
+	int i;
+
+	disable_irq(IRQ_CONTX);
+	for (i = 0; i < count; i++) {
+		while (*CSR_UARTFLG & 0x20);
+		*CSR_UARTDR = s[i];
+		if (s[i] == '\n') {
+			while (*CSR_UARTFLG & 0x20);
+			*CSR_UARTDR = '\r';
+		}
+	}
+	enable_irq(IRQ_CONTX);
+}
+
+static int rs285_console_wait_key(struct console *co)
+{
+	int c;
+
+	disable_irq(IRQ_CONRX);
+	while (*CSR_UARTFLG & 0x10);
+	c = *CSR_UARTDR;
+	enable_irq(IRQ_CONRX);
+	return c;
+}
+
+static kdev_t rs285_console_device(struct console *c)
+{
+	return MKDEV(SERIAL_21285_MAJOR, SERIAL_21285_MINOR);
+}
+
+static int __init rs285_console_setup(struct console *co, char *options)
+{
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int cflag = CREAD | HUPCL | CLOCAL;
+
+	if (machine_is_personal_server())
+		baud = 57600;
+
+	if (options) {
+		char *s = options;
+		baud = simple_strtoul(options, NULL, 10);
+		while (*s >= '0' && *s <= '9')
+			s++;
+		if (*s)
+			parity = *s++;
+		if (*s)
+			bits = *s - '0';
+	}
+
+	/*
+	 *    Now construct a cflag setting.
+	 */
+	switch (baud) {
+	case 1200:
+		cflag |= B1200;
+		break;
+	case 2400:
+		cflag |= B2400;
+		break;
+	case 4800:
+		cflag |= B4800;
+		break;
+	case 9600:
+		cflag |= B9600;
+		break;
+	case 19200:
+		cflag |= B19200;
+		break;
+	case 38400:
+		cflag |= B38400;
+		break;
+	case 57600:
+		cflag |= B57600;
+		break;
+	case 115200:
+		cflag |= B115200;
+		break;
+	default:
+		cflag |= B9600;
+		break;
+	}
+	switch (bits) {
+	case 7:
+		cflag |= CS7;
+		break;
+	default:
+		cflag |= CS8;
+		break;
+	}
+	switch (parity) {
+	case 'o':
+	case 'O':
+		cflag |= PARODD;
+		break;
+	case 'e':
+	case 'E':
+		cflag |= PARENB;
+		break;
+	}
+	co->cflag = cflag;
+	rs285_set_cflag(cflag);
+	rs285_console_write(NULL, "\e[2J\e[Hboot ", 12);
+	if (options)
+		rs285_console_write(NULL, options, strlen(options));
+	else
+		rs285_console_write(NULL, "no options", 10);
+	rs285_console_write(NULL, "\n", 1);
+
+	return 0;
+}
+
+static struct console rs285_cons =
+{
+	SERIAL_21285_NAME,
+	rs285_console_write,
+	NULL,
+	rs285_console_device,
+	rs285_console_wait_key,
+	NULL,
+	rs285_console_setup,
+	CON_PRINTBUFFER,
+	-1,
+	0,
+	NULL
+};
+
+void __init rs285_console_init(void)
+{
+	register_console(&rs285_cons);
+}
+
+#endif	/* CONFIG_SERIAL_21285_CONSOLE */