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linux/drivers/serial/serial_lh7a40x.c
Alan Cox 33f0f88f1c [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 08:01:59 -08:00

691 lines
17 KiB
C
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/* drivers/serial/serial_lh7a40x.c
*
* Copyright (C) 2004 Coastal Environmental Systems
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
*/
/* Driver for Sharp LH7A40X embedded serial ports
*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
* Based on drivers/serial/amba.c, by Deep Blue Solutions Ltd.
*
* ---
*
* This driver supports the embedded UARTs of the Sharp LH7A40X series
* CPUs. While similar to the 16550 and other UART chips, there is
* nothing close to register compatibility. Moreover, some of the
* modem control lines are not available, either in the chip or they
* are lacking in the board-level implementation.
*
* - Use of SIRDIS
* For simplicity, we disable the IR functions of any UART whenever
* we enable it.
*
*/
#include <linux/config.h>
#if defined(CONFIG_SERIAL_LH7A40X_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <asm/io.h>
#include <asm/irq.h>
#define DEV_MAJOR 204
#define DEV_MINOR 16
#define DEV_NR 3
#define ISR_LOOP_LIMIT 256
#define UR(p,o) _UR ((p)->membase, o)
#define _UR(b,o) (*((volatile unsigned int*)(((unsigned char*) b) + (o))))
#define BIT_CLR(p,o,m) UR(p,o) = UR(p,o) & (~(unsigned int)m)
#define BIT_SET(p,o,m) UR(p,o) = UR(p,o) | ( (unsigned int)m)
#define UART_REG_SIZE 32
#define UART_R_DATA (0x00)
#define UART_R_FCON (0x04)
#define UART_R_BRCON (0x08)
#define UART_R_CON (0x0c)
#define UART_R_STATUS (0x10)
#define UART_R_RAWISR (0x14)
#define UART_R_INTEN (0x18)
#define UART_R_ISR (0x1c)
#define UARTEN (0x01) /* UART enable */
#define SIRDIS (0x02) /* Serial IR disable (UART1 only) */
#define RxEmpty (0x10)
#define TxEmpty (0x80)
#define TxFull (0x20)
#define nRxRdy RxEmpty
#define nTxRdy TxFull
#define TxBusy (0x08)
#define RxBreak (0x0800)
#define RxOverrunError (0x0400)
#define RxParityError (0x0200)
#define RxFramingError (0x0100)
#define RxError (RxBreak | RxOverrunError | RxParityError | RxFramingError)
#define DCD (0x04)
#define DSR (0x02)
#define CTS (0x01)
#define RxInt (0x01)
#define TxInt (0x02)
#define ModemInt (0x04)
#define RxTimeoutInt (0x08)
#define MSEOI (0x10)
#define WLEN_8 (0x60)
#define WLEN_7 (0x40)
#define WLEN_6 (0x20)
#define WLEN_5 (0x00)
#define WLEN (0x60) /* Mask for all word-length bits */
#define STP2 (0x08)
#define PEN (0x02) /* Parity Enable */
#define EPS (0x04) /* Even Parity Set */
#define FEN (0x10) /* FIFO Enable */
#define BRK (0x01) /* Send Break */
struct uart_port_lh7a40x {
struct uart_port port;
unsigned int statusPrev; /* Most recently read modem status */
};
static void lh7a40xuart_stop_tx (struct uart_port* port)
{
BIT_CLR (port, UART_R_INTEN, TxInt);
}
static void lh7a40xuart_start_tx (struct uart_port* port)
{
BIT_SET (port, UART_R_INTEN, TxInt);
/* *** FIXME: do I need to check for startup of the
transmitter? The old driver did, but AMBA
doesn't . */
}
static void lh7a40xuart_stop_rx (struct uart_port* port)
{
BIT_SET (port, UART_R_INTEN, RxTimeoutInt | RxInt);
}
static void lh7a40xuart_enable_ms (struct uart_port* port)
{
BIT_SET (port, UART_R_INTEN, ModemInt);
}
static void
#ifdef SUPPORT_SYSRQ
lh7a40xuart_rx_chars (struct uart_port* port, struct pt_regs* regs)
#else
lh7a40xuart_rx_chars (struct uart_port* port)
#endif
{
struct tty_struct* tty = port->info->tty;
int cbRxMax = 256; /* (Gross) limit on receive */
unsigned int data, flag;/* Received data and status */
while (!(UR (port, UART_R_STATUS) & nRxRdy) && --cbRxMax) {
data = UR (port, UART_R_DATA);
flag = TTY_NORMAL;
++port->icount.rx;
if (unlikely(data & RxError)) { /* Quick check, short-circuit */
if (data & RxBreak) {
data &= ~(RxFramingError | RxParityError);
++port->icount.brk;
if (uart_handle_break (port))
continue;
}
else if (data & RxParityError)
++port->icount.parity;
else if (data & RxFramingError)
++port->icount.frame;
if (data & RxOverrunError)
++port->icount.overrun;
/* Mask by termios, leave Rx'd byte */
data &= port->read_status_mask | 0xff;
if (data & RxBreak)
flag = TTY_BREAK;
else if (data & RxParityError)
flag = TTY_PARITY;
else if (data & RxFramingError)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char (port, (unsigned char) data, regs))
continue;
uart_insert_char(port, data, RxOverrunError, data, flag);
}
tty_flip_buffer_push (tty);
return;
}
static void lh7a40xuart_tx_chars (struct uart_port* port)
{
struct circ_buf* xmit = &port->info->xmit;
int cbTxMax = port->fifosize;
if (port->x_char) {
UR (port, UART_R_DATA) = port->x_char;
++port->icount.tx;
port->x_char = 0;
return;
}
if (uart_circ_empty (xmit) || uart_tx_stopped (port)) {
lh7a40xuart_stop_tx (port);
return;
}
/* Unlike the AMBA UART, the lh7a40x UART does not guarantee
that at least half of the FIFO is empty. Instead, we check
status for every character. Using the AMBA method causes
the transmitter to drop characters. */
do {
UR (port, UART_R_DATA) = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
++port->icount.tx;
if (uart_circ_empty(xmit))
break;
} while (!(UR (port, UART_R_STATUS) & nTxRdy)
&& cbTxMax--);
if (uart_circ_chars_pending (xmit) < WAKEUP_CHARS)
uart_write_wakeup (port);
if (uart_circ_empty (xmit))
lh7a40xuart_stop_tx (port);
}
static void lh7a40xuart_modem_status (struct uart_port* port)
{
unsigned int status = UR (port, UART_R_STATUS);
unsigned int delta
= status ^ ((struct uart_port_lh7a40x*) port)->statusPrev;
BIT_SET (port, UART_R_RAWISR, MSEOI); /* Clear modem status intr */
if (!delta) /* Only happens if we missed 2 transitions */
return;
((struct uart_port_lh7a40x*) port)->statusPrev = status;
if (delta & DCD)
uart_handle_dcd_change (port, status & DCD);
if (delta & DSR)
++port->icount.dsr;
if (delta & CTS)
uart_handle_cts_change (port, status & CTS);
wake_up_interruptible (&port->info->delta_msr_wait);
}
static irqreturn_t lh7a40xuart_int (int irq, void* dev_id,
struct pt_regs* regs)
{
struct uart_port* port = dev_id;
unsigned int cLoopLimit = ISR_LOOP_LIMIT;
unsigned int isr = UR (port, UART_R_ISR);
do {
if (isr & (RxInt | RxTimeoutInt))
#ifdef SUPPORT_SYSRQ
lh7a40xuart_rx_chars(port, regs);
#else
lh7a40xuart_rx_chars(port);
#endif
if (isr & ModemInt)
lh7a40xuart_modem_status (port);
if (isr & TxInt)
lh7a40xuart_tx_chars (port);
if (--cLoopLimit == 0)
break;
isr = UR (port, UART_R_ISR);
} while (isr & (RxInt | TxInt | RxTimeoutInt));
return IRQ_HANDLED;
}
static unsigned int lh7a40xuart_tx_empty (struct uart_port* port)
{
return (UR (port, UART_R_STATUS) & TxEmpty) ? TIOCSER_TEMT : 0;
}
static unsigned int lh7a40xuart_get_mctrl (struct uart_port* port)
{
unsigned int result = 0;
unsigned int status = UR (port, UART_R_STATUS);
if (status & DCD)
result |= TIOCM_CAR;
if (status & DSR)
result |= TIOCM_DSR;
if (status & CTS)
result |= TIOCM_CTS;
return result;
}
static void lh7a40xuart_set_mctrl (struct uart_port* port, unsigned int mctrl)
{
/* None of the ports supports DTR. UART1 supports RTS through GPIO. */
/* Note, kernel appears to be setting DTR and RTS on console. */
/* *** FIXME: this deserves more work. There's some work in
tracing all of the IO pins. */
#if 0
if( port->mapbase == UART1_PHYS) {
gpioRegs_t *gpio = (gpioRegs_t *)IO_ADDRESS(GPIO_PHYS);
if (mctrl & TIOCM_RTS)
gpio->pbdr &= ~GPIOB_UART1_RTS;
else
gpio->pbdr |= GPIOB_UART1_RTS;
}
#endif
}
static void lh7a40xuart_break_ctl (struct uart_port* port, int break_state)
{
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
if (break_state == -1)
BIT_SET (port, UART_R_FCON, BRK); /* Assert break */
else
BIT_CLR (port, UART_R_FCON, BRK); /* Deassert break */
spin_unlock_irqrestore(&port->lock, flags);
}
static int lh7a40xuart_startup (struct uart_port* port)
{
int retval;
retval = request_irq (port->irq, lh7a40xuart_int, 0,
"serial_lh7a40x", port);
if (retval)
return retval;
/* Initial modem control-line settings */
((struct uart_port_lh7a40x*) port)->statusPrev
= UR (port, UART_R_STATUS);
/* There is presently no configuration option to enable IR.
Thus, we always disable it. */
BIT_SET (port, UART_R_CON, UARTEN | SIRDIS);
BIT_SET (port, UART_R_INTEN, RxTimeoutInt | RxInt);
return 0;
}
static void lh7a40xuart_shutdown (struct uart_port* port)
{
free_irq (port->irq, port);
BIT_CLR (port, UART_R_FCON, BRK | FEN);
BIT_CLR (port, UART_R_CON, UARTEN);
}
static void lh7a40xuart_set_termios (struct uart_port* port,
struct termios* termios,
struct termios* old)
{
unsigned int con;
unsigned int inten;
unsigned int fcon;
unsigned long flags;
unsigned int baud;
unsigned int quot;
baud = uart_get_baud_rate (port, termios, old, 8, port->uartclk/16);
quot = uart_get_divisor (port, baud); /* -1 performed elsewhere */
switch (termios->c_cflag & CSIZE) {
case CS5:
fcon = WLEN_5;
break;
case CS6:
fcon = WLEN_6;
break;
case CS7:
fcon = WLEN_7;
break;
case CS8:
default:
fcon = WLEN_8;
break;
}
if (termios->c_cflag & CSTOPB)
fcon |= STP2;
if (termios->c_cflag & PARENB) {
fcon |= PEN;
if (!(termios->c_cflag & PARODD))
fcon |= EPS;
}
if (port->fifosize > 1)
fcon |= FEN;
spin_lock_irqsave (&port->lock, flags);
uart_update_timeout (port, termios->c_cflag, baud);
port->read_status_mask = RxOverrunError;
if (termios->c_iflag & INPCK)
port->read_status_mask |= RxFramingError | RxParityError;
if (termios->c_iflag & (BRKINT | PARMRK))
port->read_status_mask |= RxBreak;
/* Figure mask for status we ignore */
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= RxFramingError | RxParityError;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= RxBreak;
/* Ignore overrun when ignorning parity */
/* *** FIXME: is this in the right place? */
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= RxOverrunError;
}
/* Ignore all receive errors when receive disabled */
if ((termios->c_cflag & CREAD) == 0)
port->ignore_status_mask |= RxError;
con = UR (port, UART_R_CON);
inten = (UR (port, UART_R_INTEN) & ~ModemInt);
if (UART_ENABLE_MS (port, termios->c_cflag))
inten |= ModemInt;
BIT_CLR (port, UART_R_CON, UARTEN); /* Disable UART */
UR (port, UART_R_INTEN) = 0; /* Disable interrupts */
UR (port, UART_R_BRCON) = quot - 1; /* Set baud rate divisor */
UR (port, UART_R_FCON) = fcon; /* Set FIFO and frame ctrl */
UR (port, UART_R_INTEN) = inten; /* Enable interrupts */
UR (port, UART_R_CON) = con; /* Restore UART mode */
spin_unlock_irqrestore(&port->lock, flags);
}
static const char* lh7a40xuart_type (struct uart_port* port)
{
return port->type == PORT_LH7A40X ? "LH7A40X" : NULL;
}
static void lh7a40xuart_release_port (struct uart_port* port)
{
release_mem_region (port->mapbase, UART_REG_SIZE);
}
static int lh7a40xuart_request_port (struct uart_port* port)
{
return request_mem_region (port->mapbase, UART_REG_SIZE,
"serial_lh7a40x") != NULL
? 0 : -EBUSY;
}
static void lh7a40xuart_config_port (struct uart_port* port, int flags)
{
if (flags & UART_CONFIG_TYPE) {
port->type = PORT_LH7A40X;
lh7a40xuart_request_port (port);
}
}
static int lh7a40xuart_verify_port (struct uart_port* port,
struct serial_struct* ser)
{
int ret = 0;
if (ser->type != PORT_UNKNOWN && ser->type != PORT_LH7A40X)
ret = -EINVAL;
if (ser->irq < 0 || ser->irq >= NR_IRQS)
ret = -EINVAL;
if (ser->baud_base < 9600) /* *** FIXME: is this true? */
ret = -EINVAL;
return ret;
}
static struct uart_ops lh7a40x_uart_ops = {
.tx_empty = lh7a40xuart_tx_empty,
.set_mctrl = lh7a40xuart_set_mctrl,
.get_mctrl = lh7a40xuart_get_mctrl,
.stop_tx = lh7a40xuart_stop_tx,
.start_tx = lh7a40xuart_start_tx,
.stop_rx = lh7a40xuart_stop_rx,
.enable_ms = lh7a40xuart_enable_ms,
.break_ctl = lh7a40xuart_break_ctl,
.startup = lh7a40xuart_startup,
.shutdown = lh7a40xuart_shutdown,
.set_termios = lh7a40xuart_set_termios,
.type = lh7a40xuart_type,
.release_port = lh7a40xuart_release_port,
.request_port = lh7a40xuart_request_port,
.config_port = lh7a40xuart_config_port,
.verify_port = lh7a40xuart_verify_port,
};
static struct uart_port_lh7a40x lh7a40x_ports[DEV_NR] = {
{
.port = {
.membase = (void*) io_p2v (UART1_PHYS),
.mapbase = UART1_PHYS,
.iotype = SERIAL_IO_MEM,
.irq = IRQ_UART1INTR,
.uartclk = 14745600/2,
.fifosize = 16,
.ops = &lh7a40x_uart_ops,
.flags = ASYNC_BOOT_AUTOCONF,
.line = 0,
},
},
{
.port = {
.membase = (void*) io_p2v (UART2_PHYS),
.mapbase = UART2_PHYS,
.iotype = SERIAL_IO_MEM,
.irq = IRQ_UART2INTR,
.uartclk = 14745600/2,
.fifosize = 16,
.ops = &lh7a40x_uart_ops,
.flags = ASYNC_BOOT_AUTOCONF,
.line = 1,
},
},
{
.port = {
.membase = (void*) io_p2v (UART3_PHYS),
.mapbase = UART3_PHYS,
.iotype = SERIAL_IO_MEM,
.irq = IRQ_UART3INTR,
.uartclk = 14745600/2,
.fifosize = 16,
.ops = &lh7a40x_uart_ops,
.flags = ASYNC_BOOT_AUTOCONF,
.line = 2,
},
},
};
#ifndef CONFIG_SERIAL_LH7A40X_CONSOLE
# define LH7A40X_CONSOLE NULL
#else
# define LH7A40X_CONSOLE &lh7a40x_console
static void lh7a40xuart_console_write (struct console* co,
const char* s,
unsigned int count)
{
struct uart_port* port = &lh7a40x_ports[co->index].port;
unsigned int con = UR (port, UART_R_CON);
unsigned int inten = UR (port, UART_R_INTEN);
UR (port, UART_R_INTEN) = 0; /* Disable all interrupts */
BIT_SET (port, UART_R_CON, UARTEN | SIRDIS); /* Enable UART */
for (; count-- > 0; ++s) {
while (UR (port, UART_R_STATUS) & nTxRdy)
;
UR (port, UART_R_DATA) = *s;
if (*s == '\n') {
while ((UR (port, UART_R_STATUS) & TxBusy))
;
UR (port, UART_R_DATA) = '\r';
}
}
/* Wait until all characters are sent */
while (UR (port, UART_R_STATUS) & TxBusy)
;
/* Restore control and interrupt mask */
UR (port, UART_R_CON) = con;
UR (port, UART_R_INTEN) = inten;
}
static void __init lh7a40xuart_console_get_options (struct uart_port* port,
int* baud,
int* parity,
int* bits)
{
if (UR (port, UART_R_CON) & UARTEN) {
unsigned int fcon = UR (port, UART_R_FCON);
unsigned int quot = UR (port, UART_R_BRCON) + 1;
switch (fcon & (PEN | EPS)) {
default: *parity = 'n'; break;
case PEN: *parity = 'o'; break;
case PEN | EPS: *parity = 'e'; break;
}
switch (fcon & WLEN) {
default:
case WLEN_8: *bits = 8; break;
case WLEN_7: *bits = 7; break;
case WLEN_6: *bits = 6; break;
case WLEN_5: *bits = 5; break;
}
*baud = port->uartclk/(16*quot);
}
}
static int __init lh7a40xuart_console_setup (struct console* co, char* options)
{
struct uart_port* port;
int baud = 38400;
int bits = 8;
int parity = 'n';
int flow = 'n';
if (co->index >= DEV_NR) /* Bounds check on device number */
co->index = 0;
port = &lh7a40x_ports[co->index].port;
if (options)
uart_parse_options (options, &baud, &parity, &bits, &flow);
else
lh7a40xuart_console_get_options (port, &baud, &parity, &bits);
return uart_set_options (port, co, baud, parity, bits, flow);
}
static struct uart_driver lh7a40x_reg;
static struct console lh7a40x_console = {
.name = "ttyAM",
.write = lh7a40xuart_console_write,
.device = uart_console_device,
.setup = lh7a40xuart_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &lh7a40x_reg,
};
static int __init lh7a40xuart_console_init(void)
{
register_console (&lh7a40x_console);
return 0;
}
console_initcall (lh7a40xuart_console_init);
#endif
static struct uart_driver lh7a40x_reg = {
.owner = THIS_MODULE,
.driver_name = "ttyAM",
.dev_name = "ttyAM",
.major = DEV_MAJOR,
.minor = DEV_MINOR,
.nr = DEV_NR,
.cons = LH7A40X_CONSOLE,
};
static int __init lh7a40xuart_init(void)
{
int ret;
printk (KERN_INFO "serial: LH7A40X serial driver\n");
ret = uart_register_driver (&lh7a40x_reg);
if (ret == 0) {
int i;
for (i = 0; i < DEV_NR; i++)
uart_add_one_port (&lh7a40x_reg,
&lh7a40x_ports[i].port);
}
return ret;
}
static void __exit lh7a40xuart_exit(void)
{
int i;
for (i = 0; i < DEV_NR; i++)
uart_remove_one_port (&lh7a40x_reg, &lh7a40x_ports[i].port);
uart_unregister_driver (&lh7a40x_reg);
}
module_init (lh7a40xuart_init);
module_exit (lh7a40xuart_exit);
MODULE_AUTHOR ("Marc Singer");
MODULE_DESCRIPTION ("Sharp LH7A40X serial port driver");
MODULE_LICENSE ("GPL");
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