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Commit 2c7ee6ab authored by Andrew Victor's avatar Andrew Victor Committed by Russell King
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[ARM] 4332/2: KS8695: Serial driver 



A driver for the KS8695 internal UART.

Based on the 2.6.9 driver from Micrel.

Signed-off-by: default avatarAndrew Victor <andrew@sanpeople.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent c53c9cf6

drivers/serial/Kconfig

+17 −0
Original line number Original line Diff line number Diff line
@@ -359,6 +359,23 @@ config SERIAL_ATMEL_TTYAT 




	  Say Y if you have an external 8250/16C550 UART.  If unsure, say N.

	  Say Y if you have an external 8250/16C550 UART.  If unsure, say N.





config SERIAL_KS8695

	bool "Micrel KS8695 (Centaur) serial port support"

	depends on ARCH_KS8695

	select SERIAL_CORE

	help

	  This selects the Micrel Centaur KS8695 UART.  Say Y here.



config SERIAL_KS8695_CONSOLE

	bool "Support for console on KS8695 (Centaur) serial port"

	depends on SERIAL_KS8695=y

	select SERIAL_CORE_CONSOLE

	help

	  Say Y here if you wish to use a KS8695 (Centaur) UART as the

	  system console (the system console is the device which

	  receives all kernel messages and warnings and which allows

	  logins in single user mode).



config SERIAL_CLPS711X

config SERIAL_CLPS711X

	tristate "CLPS711X serial port support"

	tristate "CLPS711X serial port support"

	depends on ARM && ARCH_CLPS711X

	depends on ARM && ARCH_CLPS711X

drivers/serial/Makefile

+1 −0
Original line number Original line Diff line number Diff line
@@ -61,3 +61,4 @@ obj-$(CONFIG_SERIAL_ATMEL) += atmel_serial.o 
obj-$(CONFIG_SERIAL_UARTLITE) += uartlite.o

obj-$(CONFIG_SERIAL_UARTLITE) += uartlite.o

obj-$(CONFIG_SERIAL_NETX) += netx-serial.o

obj-$(CONFIG_SERIAL_NETX) += netx-serial.o

obj-$(CONFIG_SERIAL_OF_PLATFORM) += of_serial.o

obj-$(CONFIG_SERIAL_OF_PLATFORM) += of_serial.o

obj-$(CONFIG_SERIAL_KS8695) += serial_ks8695.o

drivers/serial/serial_ks8695.c

0 → 100644
+657 −0
Original line number Original line Diff line number Diff line 
/*

 *  drivers/serial/serial_ks8695.c

 *

 *  Driver for KS8695 serial ports

 *

 *  Based on drivers/serial/serial_amba.c, by Kam Lee.

 *

 *  Copyright 2002-2005 Micrel Inc.

 *

 * 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.

 *

 */

#include <linux/module.h>

#include <linux/tty.h>

#include <linux/ioport.h>

#include <linux/init.h>

#include <linux/serial.h>

#include <linux/console.h>

#include <linux/sysrq.h>

#include <linux/device.h>



#include <asm/io.h>

#include <asm/irq.h>

#include <asm/mach/irq.h>



#include <asm/arch/regs-uart.h>

#include <asm/arch/regs-irq.h>



#if defined(CONFIG_SERIAL_KS8695_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)

#define SUPPORT_SYSRQ

#endif



#include <linux/serial_core.h>





#define SERIAL_KS8695_MAJOR	204

#define SERIAL_KS8695_MINOR	16

#define SERIAL_KS8695_DEVNAME	"ttyAM"



#define SERIAL_KS8695_NR	1



/*

 * Access macros for the KS8695 UART

 */

#define UART_GET_CHAR(p)	(__raw_readl((p)->membase + KS8695_URRB) & 0xFF)

#define UART_PUT_CHAR(p, c)	__raw_writel((c), (p)->membase + KS8695_URTH)

#define UART_GET_FCR(p)		__raw_readl((p)->membase + KS8695_URFC)

#define UART_PUT_FCR(p, c)	__raw_writel((c), (p)->membase + KS8695_URFC)

#define UART_GET_MSR(p)		__raw_readl((p)->membase + KS8695_URMS)

#define UART_GET_LSR(p)		__raw_readl((p)->membase + KS8695_URLS)

#define UART_GET_LCR(p)		__raw_readl((p)->membase + KS8695_URLC)

#define UART_PUT_LCR(p, c)	__raw_writel((c), (p)->membase + KS8695_URLC)

#define UART_GET_MCR(p)		__raw_readl((p)->membase + KS8695_URMC)

#define UART_PUT_MCR(p, c)	__raw_writel((c), (p)->membase + KS8695_URMC)

#define UART_GET_BRDR(p)	__raw_readl((p)->membase + KS8695_URBD)

#define UART_PUT_BRDR(p, c)	__raw_writel((c), (p)->membase + KS8695_URBD)



#define KS8695_CLR_TX_INT()	__raw_writel(1 << KS8695_IRQ_UART_TX, KS8695_IRQ_VA + KS8695_INTST)



#define UART_DUMMY_LSR_RX	0x100

#define UART_PORT_SIZE		(KS8695_USR - KS8695_URRB + 4)



#define tx_enabled(port) ((port)->unused[0])

#define rx_enabled(port) ((port)->unused[1])





#ifdef SUPPORT_SYSRQ

static struct console ks8695_console;

#endif



static void ks8695uart_stop_tx(struct uart_port *port)

{

	if (tx_enabled(port)) {

		disable_irq(KS8695_IRQ_UART_TX);

		tx_enabled(port) = 0;

	}

}



static void ks8695uart_start_tx(struct uart_port *port)

{

	if (!tx_enabled(port)) {

		enable_irq(KS8695_IRQ_UART_TX);

		tx_enabled(port) = 1;

	}

}



static void ks8695uart_stop_rx(struct uart_port *port)

{

	if (rx_enabled(port)) {

		disable_irq(KS8695_IRQ_UART_RX);

		rx_enabled(port) = 0;

	}

}



static void ks8695uart_enable_ms(struct uart_port *port)

{

	enable_irq(KS8695_IRQ_UART_MODEM_STATUS);

}



static void ks8695uart_disable_ms(struct uart_port *port)

{

	disable_irq(KS8695_IRQ_UART_MODEM_STATUS);

}



static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)

{

	struct uart_port *port = dev_id;

	struct tty_struct *tty = port->info->tty;

	unsigned int status, ch, lsr, flg, max_count = 256;



	status = UART_GET_LSR(port);		/* clears pending LSR interrupts */

	while ((status & URLS_URDR) && max_count--) {

		ch = UART_GET_CHAR(port);

		flg = TTY_NORMAL;



		port->icount.rx++;



		/*

		 * Note that the error handling code is

		 * out of the main execution path

		 */

		lsr = UART_GET_LSR(port) | UART_DUMMY_LSR_RX;

		if (unlikely(lsr & (URLS_URBI | URLS_URPE | URLS_URFE | URLS_URROE))) {

			if (lsr & URLS_URBI) {

				lsr &= ~(URLS_URFE | URLS_URPE);

				port->icount.brk++;

				if (uart_handle_break(port))

					goto ignore_char;

			}

			if (lsr & URLS_URPE)

				port->icount.parity++;

			if (lsr & URLS_URFE)

				port->icount.frame++;

			if (lsr & URLS_URROE)

				port->icount.overrun++;



			lsr &= port->read_status_mask;



			if (lsr & URLS_URBI)

				flg = TTY_BREAK;

			else if (lsr & URLS_URPE)

				flg = TTY_PARITY;

			else if (lsr & URLS_URFE)

				flg = TTY_FRAME;

		}



		if (uart_handle_sysrq_char(port, ch))

			goto ignore_char;



		uart_insert_char(port, lsr, URLS_URROE, ch, flg);



ignore_char:

		status = UART_GET_LSR(port);

	}

	tty_flip_buffer_push(tty);



	return IRQ_HANDLED;

}





static irqreturn_t ks8695uart_tx_chars(int irq, void *dev_id)

{

	struct uart_port *port = dev_id;

	struct circ_buf *xmit = &port->info->xmit;

	unsigned int count;



	if (port->x_char) {

		KS8695_CLR_TX_INT();

		UART_PUT_CHAR(port, port->x_char);

		port->icount.tx++;

		port->x_char = 0;

		return IRQ_HANDLED;

	}



	if (uart_tx_stopped(port) || uart_circ_empty(xmit)) {

		ks8695uart_stop_tx(port);

		return IRQ_HANDLED;

	}



	count = 16;	/* fifo size */

	while (!uart_circ_empty(xmit) && (count-- > 0)) {

		KS8695_CLR_TX_INT();

		UART_PUT_CHAR(port, xmit->buf[xmit->tail]);



		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);

		port->icount.tx++;

	}



	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)

		uart_write_wakeup(port);



	if (uart_circ_empty(xmit))

		ks8695uart_stop_tx(port);



	return IRQ_HANDLED;

}



static irqreturn_t ks8695uart_modem_status(int irq, void *dev_id)

{

	struct uart_port *port = dev_id;

	unsigned int status;



	/*

	 * clear modem interrupt by reading MSR

	 */

	status = UART_GET_MSR(port);



	if (status & URMS_URDDCD)

		uart_handle_dcd_change(port, status & URMS_URDDCD);



	if (status & URMS_URDDST)

		port->icount.dsr++;



	if (status & URMS_URDCTS)

		uart_handle_cts_change(port, status & URMS_URDCTS);



	if (status & URMS_URTERI)

		port->icount.rng++;



	wake_up_interruptible(&port->info->delta_msr_wait);



	return IRQ_HANDLED;

}



static unsigned int ks8695uart_tx_empty(struct uart_port *port)

{

	return (UART_GET_LSR(port) & URLS_URTE) ? TIOCSER_TEMT : 0;

}



static unsigned int ks8695uart_get_mctrl(struct uart_port *port)

{

	unsigned int result = 0;

	unsigned int status;



	status = UART_GET_MSR(port);

	if (status & URMS_URDCD)

		result |= TIOCM_CAR;

	if (status & URMS_URDSR)

		result |= TIOCM_DSR;

	if (status & URMS_URCTS)

		result |= TIOCM_CTS;

	if (status & URMS_URRI)

		result |= TIOCM_RI;



	return result;

}



static void ks8695uart_set_mctrl(struct uart_port *port, u_int mctrl)

{

	unsigned int mcr;



	mcr = UART_GET_MCR(port);

	if (mctrl & TIOCM_RTS)

		mcr |= URMC_URRTS;

	else

		mcr &= ~URMC_URRTS;



	if (mctrl & TIOCM_DTR)

		mcr |= URMC_URDTR;

	else

		mcr &= ~URMC_URDTR;



	UART_PUT_MCR(port, mcr);

}



static void ks8695uart_break_ctl(struct uart_port *port, int break_state)

{

	unsigned int lcr;



	lcr = UART_GET_LCR(port);



	if (break_state == -1)

		lcr |= URLC_URSBC;

	else

		lcr &= ~URLC_URSBC;



	UART_PUT_LCR(port, lcr);

}



static int ks8695uart_startup(struct uart_port *port)

{

	int retval;



	set_irq_flags(KS8695_IRQ_UART_TX, IRQF_VALID | IRQF_NOAUTOEN);

	tx_enabled(port) = 0;

	rx_enabled(port) = 1;



	/*

	 * Allocate the IRQ

	 */

	retval = request_irq(KS8695_IRQ_UART_TX, ks8695uart_tx_chars, IRQF_DISABLED, "UART TX", port);

	if (retval)

		goto err_tx;



	retval = request_irq(KS8695_IRQ_UART_RX, ks8695uart_rx_chars, IRQF_DISABLED, "UART RX", port);

	if (retval)

		goto err_rx;



	retval = request_irq(KS8695_IRQ_UART_LINE_STATUS, ks8695uart_rx_chars, IRQF_DISABLED, "UART LineStatus", port);

	if (retval)

		return err_ls;



	retval = request_irq(KS8695_IRQ_UART_MODEM_STATUS, ks8695uart_modem_status, IRQF_DISABLED, "UART ModemStatus", port);

	if (retval)

		return err_ms;



	return 0;



err_ms:

	free_irq(KS8695_IRQ_UART_LINE_STATUS, port);

err_ls:

	free_irq(KS8695_IRQ_UART_RX, port);

err_rx:

	free_irq(KS8695_IRQ_UART_TX, port);

err_tx:

	return retval;

}



static void ks8695uart_shutdown(struct uart_port *port)

{

	/*

	 * Free the interrupt

	 */

	free_irq(KS8695_IRQ_UART_RX, port);

	free_irq(KS8695_IRQ_UART_TX, port);

	free_irq(KS8695_IRQ_UART_MODEM_STATUS, port);

	free_irq(KS8695_IRQ_UART_LINE_STATUS, port);



	/* disable break condition and fifos */

	UART_PUT_LCR(port, UART_GET_LCR(port) & ~URLC_URSBC);

	UART_PUT_FCR(port, UART_GET_FCR(port) & ~URFC_URFE);

}



static void ks8695uart_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old)

{

	unsigned int lcr, fcr = 0;

	unsigned long flags;

	unsigned int baud, quot;



	/*

	 * Ask the core to calculate the divisor for us.

	 */

	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);

	quot = uart_get_divisor(port, baud);



	switch (termios->c_cflag & CSIZE) {

	case CS5:

		lcr = URCL_5;

		break;

	case CS6:

		lcr = URCL_6;

		break;

	case CS7:

		lcr = URCL_7;

		break;

	default:

		lcr = URCL_8;

		break;

	}



	/* stop bits */

	if (termios->c_cflag & CSTOPB)

		lcr |= URLC_URSB;



	/* parity */

	if (termios->c_cflag & PARENB) {

		if (termios->c_cflag & CMSPAR) {	/* Mark or Space parity */

			if (termios->c_cflag & PARODD)

				lcr |= URPE_MARK;

			else

				lcr |= URPE_SPACE;

		}

		else if (termios->c_cflag & PARODD)

			lcr |= URPE_ODD;

		else

			lcr |= URPE_EVEN;

	}



	if (port->fifosize > 1)

		fcr = URFC_URFRT_8 | URFC_URTFR | URFC_URRFR | URFC_URFE;



	spin_lock_irqsave(&port->lock, flags);



	/*

	 * Update the per-port timeout.

	 */

	uart_update_timeout(port, termios->c_cflag, baud);



	port->read_status_mask = URLS_URROE;

	if (termios->c_iflag & INPCK)

		port->read_status_mask |= (URLS_URFE | URLS_URPE);

	if (termios->c_iflag & (BRKINT | PARMRK))

		port->read_status_mask |= URLS_URBI;



	/*

	 * Characters to ignore

	 */

	port->ignore_status_mask = 0;

	if (termios->c_iflag & IGNPAR)

		port->ignore_status_mask |= (URLS_URFE | URLS_URPE);

	if (termios->c_iflag & IGNBRK) {

		port->ignore_status_mask |= URLS_URBI;

		/*

		 * If we're ignoring parity and break indicators,

		 * ignore overruns too (for real raw support).

		 */

		if (termios->c_iflag & IGNPAR)

			port->ignore_status_mask |= URLS_URROE;

	}



	/*

	 * Ignore all characters if CREAD is not set.

	 */

	if ((termios->c_cflag & CREAD) == 0)

		port->ignore_status_mask |= UART_DUMMY_LSR_RX;



	/* first, disable everything */

	if (UART_ENABLE_MS(port, termios->c_cflag))

		ks8695uart_enable_ms(port);

	else

		ks8695uart_disable_ms(port);



	/* Set baud rate */

	UART_PUT_BRDR(port, quot);



	UART_PUT_LCR(port, lcr);

	UART_PUT_FCR(port, fcr);



	spin_unlock_irqrestore(&port->lock, flags);

}



static const char *ks8695uart_type(struct uart_port *port)

{

	return port->type == PORT_KS8695 ? "KS8695" : NULL;

}



/*

 * Release the memory region(s) being used by 'port'

 */

static void ks8695uart_release_port(struct uart_port *port)

{

	release_mem_region(port->mapbase, UART_PORT_SIZE);

}



/*

 * Request the memory region(s) being used by 'port'

 */

static int ks8695uart_request_port(struct uart_port *port)

{

	return request_mem_region(port->mapbase, UART_PORT_SIZE,

			"serial_ks8695") != NULL ? 0 : -EBUSY;

}



/*

 * Configure/autoconfigure the port.

 */

static void ks8695uart_config_port(struct uart_port *port, int flags)

{

	if (flags & UART_CONFIG_TYPE) {

		port->type = PORT_KS8695;

		ks8695uart_request_port(port);

	}

}



/*

 * verify the new serial_struct (for TIOCSSERIAL).

 */

static int ks8695uart_verify_port(struct uart_port *port, struct serial_struct *ser)

{

	int ret = 0;



	if (ser->type != PORT_UNKNOWN && ser->type != PORT_KS8695)

		ret = -EINVAL;

	if (ser->irq != port->irq)

		ret = -EINVAL;

	if (ser->baud_base < 9600)

		ret = -EINVAL;

	return ret;

}



static struct uart_ops ks8695uart_pops = {

	.tx_empty	= ks8695uart_tx_empty,

	.set_mctrl	= ks8695uart_set_mctrl,

	.get_mctrl	= ks8695uart_get_mctrl,

	.stop_tx	= ks8695uart_stop_tx,

	.start_tx	= ks8695uart_start_tx,

	.stop_rx	= ks8695uart_stop_rx,

	.enable_ms	= ks8695uart_enable_ms,

	.break_ctl	= ks8695uart_break_ctl,

	.startup	= ks8695uart_startup,

	.shutdown	= ks8695uart_shutdown,

	.set_termios	= ks8695uart_set_termios,

	.type		= ks8695uart_type,

	.release_port	= ks8695uart_release_port,

	.request_port	= ks8695uart_request_port,

	.config_port	= ks8695uart_config_port,

	.verify_port	= ks8695uart_verify_port,

};



static struct uart_port ks8695uart_ports[SERIAL_KS8695_NR] = {

	{

		.membase	= (void *) KS8695_UART_VA,

		.mapbase	= KS8695_UART_VA,

		.iotype		= SERIAL_IO_MEM,

		.irq		= KS8695_IRQ_UART_TX,

		.uartclk	= CLOCK_TICK_RATE * 16,

		.fifosize	= 16,

		.ops		= &ks8695uart_pops,

		.flags		= ASYNC_BOOT_AUTOCONF,

		.line		= 0,

	}

};



#ifdef CONFIG_SERIAL_KS8695_CONSOLE

static void ks8695_console_putchar(struct uart_port *port, int ch)

{

	while (!(UART_GET_LSR(port) & URLS_URTHRE))

		barrier();



	UART_PUT_CHAR(port, ch);

}



static void ks8695_console_write(struct console *co, const char *s, u_int count)

{

	struct uart_port *port = ks8695uart_ports + co->index;



	uart_console_write(port, s, count, ks8695_console_putchar);

}



static void __init ks8695_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits)

{

	unsigned int lcr;



	lcr = UART_GET_LCR(port);



	switch (lcr & URLC_PARITY) {

		case URPE_ODD:

			*parity = 'o';

			break;

		case URPE_EVEN:

			*parity = 'e';

			break;

		default:

			*parity = 'n';

	}



	switch (lcr & URLC_URCL) {

		case URCL_5:

			*bits = 5;

			break;

		case URCL_6:

			*bits = 6;

			break;

		case URCL_7:

			*bits = 7;

			break;

		default:

			*bits = 8;

	}



	*baud = port->uartclk / (UART_GET_BRDR(port) & 0x0FFF);

	*baud /= 16;

	*baud &= 0xFFFFFFF0;

}



static int __init ks8695_console_setup(struct console *co, char *options)

{

	struct uart_port *port;

	int baud = 115200;

	int bits = 8;

	int parity = 'n';

	int flow = 'n';



	/*

	 * Check whether an invalid uart number has been specified, and

	 * if so, search for the first available port that does have

	 * console support.

	 */

	port = uart_get_console(ks8695uart_ports, SERIAL_KS8695_NR, co);



	if (options)

		uart_parse_options(options, &baud, &parity, &bits, &flow);

	else

		ks8695_console_get_options(port, &baud, &parity, &bits);



	return uart_set_options(port, co, baud, parity, bits, flow);

}



extern struct uart_driver ks8695_reg;



static struct console ks8695_console = {

	.name		= SERIAL_KS8695_DEVNAME,

	.write		= ks8695_console_write,

	.device		= uart_console_device,

	.setup		= ks8695_console_setup,

	.flags		= CON_PRINTBUFFER,

	.index		= -1,

	.data		= &ks8695_reg,

};



static int __init ks8695_console_init(void)

{

	register_console(&ks8695_console);

	return 0;

}



console_initcall(ks8695_console_init);



#define KS8695_CONSOLE	&ks8695_console

#else

#define KS8695_CONSOLE	NULL

#endif



static struct uart_driver ks8695_reg = {

	.owner			= THIS_MODULE,

	.driver_name		= "serial_ks8695",

	.dev_name		= SERIAL_KS8695_DEVNAME,

	.major			= SERIAL_KS8695_MAJOR,

	.minor			= SERIAL_KS8695_MINOR,

	.nr			= SERIAL_KS8695_NR,

	.cons			= KS8695_CONSOLE,

};



static int __init ks8695uart_init(void)

{

	int i, ret;



	printk(KERN_INFO "Serial: Micrel KS8695 UART driver\n");



	ret = uart_register_driver(&ks8695_reg);

	if (ret)

		return ret;



	for (i = 0; i < SERIAL_KS8695_NR; i++)

		uart_add_one_port(&ks8695_reg, &ks8695uart_ports[0]);



	return 0;

}



static void __exit ks8695uart_exit(void)

{

	int i;



	for (i = 0; i < SERIAL_KS8695_NR; i++)

		uart_remove_one_port(&ks8695_reg, &ks8695uart_ports[0]);

	uart_unregister_driver(&ks8695_reg);

}



module_init(ks8695uart_init);

module_exit(ks8695uart_exit);



MODULE_DESCRIPTION("KS8695 serial port driver");

MODULE_AUTHOR("Micrel Inc.");

MODULE_LICENSE("GPL");

include/linux/serial_core.h

+4 −0
Original line number Original line Diff line number Diff line
@@ -139,6 +139,10 @@ 
/* Blackfin bf5xx */

/* Blackfin bf5xx */

#define PORT_BFIN	75

#define PORT_BFIN	75





/* Micrel KS8695 */

#define PORT_KS8695	76





#ifdef __KERNEL__

#ifdef __KERNEL__





#include <linux/compiler.h>

#include <linux/compiler.h>