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nuttx-bb/nuttx/arch/arm/src/c5471/c5471_serial.c

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/****************************************************************************
* c5471/c5471_serial.c
*
* Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <unistd.h>
#include <semaphore.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <nuttx/serial.h>
#include <arch/serial.h>
#include "chip.h"
#include "up_arch.h"
#include "os_internal.h"
#include "up_internal.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define BASE_BAUD 115200
#if defined(CONFIG_UART_IRDA_HWFLOWCONTROL) || defined(CONFIG_UART_MODEM_HWFLOWCONTROL)
# define CONFIG_UART_HWFLOWCONTROL
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct uart_regs_s
{
uint32_t ier;
uint32_t lcr;
uint32_t fcr;
#ifdef CONFIG_UART_HWFLOWCONTROL
uint32_t efr;
uint32_t tcr;
#endif
};
struct up_dev_s
{
unsigned int uartbase; /* Base address of UART registers */
unsigned int baud_base; /* Base baud for conversions */
unsigned int baud; /* Configured baud */
uint8_t xmit_fifo_size; /* Size of transmit FIFO */
uint8_t irq; /* IRQ associated with this UART */
uint8_t parity; /* 0=none, 1=odd, 2=even */
uint8_t bits; /* Number of bits (7 or 8) */
#ifdef CONFIG_UART_HWFLOWCONTROL
bool flowcontrol; /* true: Hardware flow control
* is enabled. */
#endif
bool stopbits2; /* true: Configure with 2
* stop bits instead of 1 */
struct uart_regs_s regs; /* Shadow copy of readonly regs */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int up_setup(struct uart_dev_s *dev);
static void up_shutdown(struct uart_dev_s *dev);
static int up_attach(struct uart_dev_s *dev);
static void up_detach(struct uart_dev_s *dev);
static int up_interrupt(int irq, void *context);
static int up_ioctl(struct file *filep, int cmd, unsigned long arg);
static int up_receive(struct uart_dev_s *dev, unsigned int *status);
static void up_rxint(struct uart_dev_s *dev, bool enable);
static bool up_rxavailable(struct uart_dev_s *dev);
static void up_send(struct uart_dev_s *dev, int ch);
static void up_txint(struct uart_dev_s *dev, bool enable);
static bool up_txready(struct uart_dev_s *dev);
static bool up_txempty(struct uart_dev_s *dev);
/****************************************************************************
* Private Variables
****************************************************************************/
struct uart_ops_s g_uart_ops =
{
.setup = up_setup,
.shutdown = up_shutdown,
.attach = up_attach,
.detach = up_detach,
.ioctl = up_ioctl,
.receive = up_receive,
.rxint = up_rxint,
.rxavailable = up_rxavailable,
.send = up_send,
.txint = up_txint,
.txready = up_txready,
.txempty = up_txempty,
};
/* I/O buffers */
static char g_irdarxbuffer[CONFIG_UART_IRDA_RXBUFSIZE];
static char g_irdatxbuffer[CONFIG_UART_IRDA_TXBUFSIZE];
static char g_modemrxbuffer[CONFIG_UART_MODEM_RXBUFSIZE];
static char g_modemtxbuffer[CONFIG_UART_MODEM_TXBUFSIZE];
/* This describes the state of the C5471 serial IRDA port. */
static struct up_dev_s g_irdapriv =
{
.xmit_fifo_size = UART_IRDA_XMIT_FIFO_SIZE,
.baud_base = BASE_BAUD,
.uartbase = UART_IRDA_BASE,
.baud = CONFIG_UART_IRDA_BAUD,
.irq = C5471_IRQ_UART_IRDA,
.parity = CONFIG_UART_IRDA_PARITY,
.bits = CONFIG_UART_IRDA_BITS,
#ifdef CONFIG_UART_IRDA_HWFLOWCONTROL
.flowcontrol = true,
#endif
.stopbits2 = CONFIG_UART_IRDA_2STOP,
};
static uart_dev_t g_irdaport =
{
.recv =
{
.size = CONFIG_UART_IRDA_RXBUFSIZE,
.buffer = g_irdarxbuffer,
},
.xmit =
{
.size = CONFIG_UART_IRDA_TXBUFSIZE,
.buffer = g_irdatxbuffer,
},
.ops = &g_uart_ops,
.priv = &g_irdapriv,
};
/* This describes the state of the C5471 serial Modem port. */
static struct up_dev_s g_modempriv =
{
.xmit_fifo_size = UART_XMIT_FIFO_SIZE,
.baud_base = BASE_BAUD,
.uartbase = UART_MODEM_BASE,
.baud = CONFIG_UART_MODEM_BAUD,
.irq = C5471_IRQ_UART,
.parity = CONFIG_UART_MODEM_PARITY,
.bits = CONFIG_UART_MODEM_BITS,
#ifdef CONFIG_UART_MODEM_HWFLOWCONTROL
.flowcontrol = true,
#endif
.stopbits2 = CONFIG_UART_MODEM_2STOP,
};
static uart_dev_t g_modemport =
{
.recv =
{
.size = CONFIG_UART_MODEM_RXBUFSIZE,
.buffer = g_modemrxbuffer,
},
.xmit =
{
.size = CONFIG_UART_MODEM_TXBUFSIZE,
.buffer = g_modemtxbuffer,
},
.ops = &g_uart_ops,
.priv = &g_modempriv,
};
/* Now, which one with be tty0/console and which tty1? */
#ifdef CONFIG_SERIAL_IRDA_CONSOLE
# define CONSOLE_DEV g_irdaport
# define TTYS0_DEV g_irdaport
# define TTYS1_DEV g_modemport
#else
# define CONSOLE_DEV g_modemport
# define TTYS0_DEV g_modemport
# define TTYS1_DEV g_irdaport
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_inserial
****************************************************************************/
static inline uint32_t up_inserial(struct up_dev_s *priv, uint32_t offset)
{
return getreg32(priv->uartbase + offset);
}
/****************************************************************************
* Name: up_serialout
****************************************************************************/
static inline void up_serialout(struct up_dev_s *priv, uint32_t offset, uint32_t value)
{
putreg32(value, priv->uartbase + offset);
}
/****************************************************************************
* Name: up_disableuartint
****************************************************************************/
static inline void up_disableuartint(struct up_dev_s *priv, uint16_t *ier)
{
if (ier)
{
*ier = priv->regs.ier & UART_IER_INTMASK;
}
priv->regs.ier &= ~UART_IER_INTMASK;
up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
}
/****************************************************************************
* Name: up_restoreuartint
****************************************************************************/
static inline void up_restoreuartint(struct up_dev_s *priv, uint16_t ier)
{
priv->regs.ier |= ier & (UART_IER_RECVINT|UART_IER_XMITINT);
up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
}
/****************************************************************************
* Name: up_waittxready
****************************************************************************/
static inline void up_waittxready(struct up_dev_s *priv)
{
int tmp;
for (tmp = 1000 ; tmp > 0 ; tmp--)
{
if ((up_inserial(priv, UART_SSR_OFFS) & UART_SSR_TXFULL) == 0)
{
break;
}
}
}
/****************************************************************************
* Name: up_disablebreaks
****************************************************************************/
static inline void up_disablebreaks(struct up_dev_s *priv)
{
priv->regs.lcr &= ~UART_LCR_BOC;
up_serialout(priv, UART_LCR_OFFS, priv->regs.lcr);
}
/****************************************************************************
* Name: up_enablebreaks
****************************************************************************/
static inline void up_enablebreaks(struct up_dev_s *priv)
{
priv->regs.lcr |= UART_LCR_BOC;
up_serialout(priv, UART_LCR_OFFS, priv->regs.lcr);
}
/****************************************************************************
* Name: up_setrate
****************************************************************************/
static inline void up_setrate(struct up_dev_s *priv, unsigned int rate)
{
uint32_t div_bit_rate;
switch (rate)
{
case 115200:
div_bit_rate = BAUD_115200;
break;
case 57600:
div_bit_rate = BAUD_57600;
break;
case 38400:
div_bit_rate = BAUD_38400;
break;
case 19200:
div_bit_rate = BAUD_19200;
break;
case 4800:
div_bit_rate = BAUD_4800;
break;
case 2400:
div_bit_rate = BAUD_2400;
break;
case 1200:
div_bit_rate = BAUD_1200;
break;
case 9600:
default:
div_bit_rate = BAUD_9600;
break;
}
up_serialout(priv, UART_DIV_BIT_RATE_OFFS, div_bit_rate);
}
/****************************************************************************
* Name: up_setup
*
* Description:
* Configure the UART baud, bits, parity, fifos, etc. This
* method is called the first time that the serial port is
* opened.
*
****************************************************************************/
static int up_setup(struct uart_dev_s *dev)
{
#ifndef CONFIG_SUPPRESS_UART_CONFIG
struct up_dev_s *priv = dev->priv;
unsigned int cval;
if (priv->bits == 7)
{
cval = UART_LCR_7BITS;
}
else
{
cval = UART_LCR_8BITS;
}
if (priv->stopbits2)
{
cval |= UART_LCR_2STOP;
}
if (priv->parity == 1) /* Odd parity */
{
cval |= (UART_LCR_PAREN|UART_LCR_PARODD);
}
else if (priv->parity == 2) /* Even parity */
{
cval |= (UART_LCR_PAREN|UART_LCR_PAREVEN);
}
/* Both the IrDA and MODEM UARTs support RESET and UART mode. */
up_serialout(priv, UART_MDR_OFFS, MDR_RESET_MODE);
up_mdelay(5);
up_serialout(priv, UART_MDR_OFFS, MDR_UART_MODE);
up_mdelay(5);
priv->regs.ier = up_inserial(priv, UART_IER_OFFS);
priv->regs.lcr = up_inserial(priv, UART_LCR_OFFS);
#ifdef CONFIG_UART_HWFLOWCONTROL
if (priv->flowcontrol)
{
priv->regs.efr = up_inserial(priv, UART_EFR_OFFS);
priv->regs.tcr = up_inserial(priv, UART_TCR_OFFS);
}
#endif
up_disableuartint(priv, NULL);
up_serialout(priv, UART_EFR_OFFS, 0x0010); /* Enable fifo control */
up_serialout(priv, UART_TFCR_OFFS, 0); /* Reset to 0 */
up_serialout(priv, UART_RFCR_OFFS, UART_FCR_RX_CLR); /* Clear RX fifo */
up_serialout(priv, UART_TFCR_OFFS, UART_FCR_TX_CLR); /* Clear TX fifo */
up_serialout(priv, UART_TFCR_OFFS, UART_FCR_FIFO_EN); /* Enable RX/TX fifos */
up_disablebreaks(priv);
/* Set the RX and TX trigger levels to the minimum */
priv->regs.fcr = (priv->regs.fcr & 0xffffffcf) | UART_FCR_FTL;
up_serialout(priv, UART_RFCR_OFFS, priv->regs.fcr);
priv->regs.fcr = (priv->regs.fcr & 0xffffff3f) | UART_FCR_FTL;
up_serialout(priv, UART_RFCR_OFFS, priv->regs.fcr);
up_setrate(priv, priv->baud);
priv->regs.lcr &= 0xffffffe0; /* clear original field, and... */
priv->regs.lcr |= (uint32_t)cval; /* Set new bits in that field. */
up_serialout(priv, UART_LCR_OFFS, priv->regs.lcr);
#ifdef CONFIG_UART_HWFLOWCONTROL
if (priv->flowcontrol)
{
/* Set the FIFO level triggers for flow control
* Halt = 48 bytes, resume = 12 bytes
*/
priv->regs.tcr = (priv->regs.tcr & 0xffffff00) | 0x0000003c;
up_serialout(priv, UART_TCR_OFFS, priv->regs.tcr);
/* Enable RTS/CTS flow control */
priv->regs.efr |= 0x000000c0;
up_serialout(priv, UART_EFR_OFFS, priv->regs.efr);
}
else
{
/* Disable RTS/CTS flow control */
priv->regs.efr &= 0xffffff3f;
up_serialout(priv, UART_EFR_OFFS, priv->regs.efr);
}
#endif
#endif
return OK;
}
/****************************************************************************
* Name: up_shutdown
*
* Description:
* Disable the UART. This method is called when the serial port is closed
*
****************************************************************************/
static void up_shutdown(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)CONSOLE_DEV.priv;
up_disableuartint(priv, NULL);
}
/****************************************************************************
* Name: up_attach
*
* Description:
* Configure the UART to operation in interrupt driven mode. This method is
* called when the serial port is opened. Normally, this is just after the
* the setup() method is called, however, the serial console may operate in
* a non-interrupt driven mode during the boot phase.
*
* RX and TX interrupts are not enabled when by the attach method (unless the
* hardware supports multiple levels of interrupt enabling). The RX and TX
* interrupts are not enabled until the txint() and rxint() methods are called.
*
****************************************************************************/
static int up_attach(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
int ret;
/* Attach and enable the IRQ */
ret = irq_attach(priv->irq, up_interrupt);
if (ret == OK)
{
/* Enable the interrupt (RX and TX interrupts are still disabled
* in the UART
*/
up_enable_irq(priv->irq);
}
return ret;
}
/****************************************************************************
* Name: up_detach
*
* Description:
* Detach UART interrupts. This method is called when the serial port is
* closed normally just before the shutdown method is called. The exception is
* the serial console which is never shutdown.
*
****************************************************************************/
static void up_detach(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
up_disable_irq(priv->irq);
irq_detach(priv->irq);
}
/****************************************************************************
* Name: up_interrupt
*
* Description:
* This is the UART interrupt handler. It will be invoked
* when an interrupt received on the 'irq' It should call
* uart_transmitchars or uart_receivechar to perform the
* appropriate data transfers. The interrupt handling logic\
* must be able to map the 'irq' number into the approprite
* uart_dev_s structure in order to call these functions.
*
****************************************************************************/
static int up_interrupt(int irq, void *context)
{
struct uart_dev_s *dev = NULL;
struct up_dev_s *priv;
volatile uint32_t cause;
if (g_irdapriv.irq == irq)
{
dev = &g_irdaport;
}
else if (g_modempriv.irq == irq)
{
dev = &g_modemport;
}
else
{
PANIC(OSERR_INTERNAL);
}
priv = (struct up_dev_s*)dev->priv;
cause = up_inserial(priv, UART_ISR_OFFS) & 0x0000003f;
if ((cause & 0x0000000c) == 0x0000000c)
{
uint32_t ier_val = 0;
/* Is this an interrupt from the IrDA UART? */
if (irq == C5471_IRQ_UART_IRDA)
{
/* Save the currently enabled IrDA UART interrupts
* so that we can restore the IrDA interrupt state
* below.
*/
ier_val = up_inserial(priv, UART_IER_OFFS);
/* Then disable all IrDA UART interrupts */
up_serialout(priv, UART_IER_OFFS, 0);
}
/* Receive characters from the RX fifo */
uart_recvchars(dev);
/* read UART_RHR to clear int condition
* toss = up_inserialchar(priv,&status);
*/
/* Is this an interrupt from the IrDA UART? */
if (irq == C5471_IRQ_UART_IRDA)
{
/* Restore the IrDA UART interrupt enables */
up_serialout(priv, UART_IER_OFFS, ier_val);
}
}
else if ((cause & 0x0000000c) == 0x00000004)
{
uart_recvchars(dev);
}
if ((cause & 0x00000002) != 0)
{
uart_xmitchars(dev);
}
return OK;
}
/****************************************************************************
* Name: up_ioctl
*
* Description:
* All ioctl calls will be routed through this method
*
****************************************************************************/
static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
{
struct inode *inode = filep->f_inode;
struct uart_dev_s *dev = inode->i_private;
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
int ret = OK;
switch (cmd)
{
case TIOCSERGSTRUCT:
{
struct up_dev_s *user = (struct up_dev_s*)arg;
if (!user)
{
*get_errno_ptr() = EINVAL;
ret = ERROR;
}
else
{
memcpy(user, dev, sizeof(struct up_dev_s));
}
}
break;
case TIOCSBRK: /* BSD compatibility: Turn break on, unconditionally */
{
irqstate_t flags = irqsave();
up_enablebreaks(priv);
irqrestore(flags);
}
break;
case TIOCCBRK: /* BSD compatibility: Turn break off, unconditionally */
{
irqstate_t flags;
flags = irqsave();
up_disablebreaks(priv);
irqrestore(flags);
}
break;
default:
*get_errno_ptr() = ENOTTY;
ret = ERROR;
break;
}
return ret;
}
/****************************************************************************
* Name: up_receive
*
* Description:
* Called (usually) from the interrupt level to receive one character from
* the UART. Error bits associated with the receipt are provided in the
* the return 'status'.
*
****************************************************************************/
static int up_receive(struct uart_dev_s *dev, unsigned int *status)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint32_t rhr;
uint32_t lsr;
/* Construct a 16bit status word that uses the high byte to
* hold the status bits associated with framing,parity,break
* and a low byte that holds error bits of LSR for
* conditions such as overflow, etc.
*/
rhr = up_inserial(priv, UART_RHR_OFFS);
lsr = up_inserial(priv, UART_LSR_OFFS);
*status = (unsigned int)((rhr & 0x0000ff00) | (lsr & 0x000000ff));
return rhr & 0x000000ff;
}
/****************************************************************************
* Name: up_rxint
*
* Description:
* Call to enable or disable RX interrupts
*
****************************************************************************/
static void up_rxint(struct uart_dev_s *dev, bool enable)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
if (enable)
{
#ifndef CONFIG_SUPPRESS_SERIAL_INTS
priv->regs.ier |= UART_IER_RECVINT;
up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
#endif
}
else
{
priv->regs.ier &= ~UART_IER_RECVINT;
up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
}
}
/****************************************************************************
* Name: up_rxavailable
*
* Description:
* Return true if the receive fifo is not empty
*
****************************************************************************/
static bool up_rxavailable(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
return up_inserial(priv, UART_LSR_OFFS) & UART_RX_FIFO_NOEMPTY;
}
/****************************************************************************
* Name: up_send
*
* Description:
* This method will send one byte on the UART
*
****************************************************************************/
static void up_send(struct uart_dev_s *dev, int ch)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
up_serialout(priv, UART_THR_OFFS, (uint8_t)ch);
}
/****************************************************************************
* Name: up_txint
*
* Description:
* Call to enable or disable TX interrupts
*
****************************************************************************/
static void up_txint(struct uart_dev_s *dev, bool enable)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
if (enable)
{
#ifndef CONFIG_SUPPRESS_SERIAL_INTS
priv->regs.ier |= UART_IER_XMITINT;
up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
#endif
}
else
{
priv->regs.ier &= ~UART_IER_XMITINT;
up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
}
}
/****************************************************************************
* Name: up_txready
*
* Description:
* Return true if the tranmsit fifo is not full
*
****************************************************************************/
static bool up_txready(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
return (up_inserial(priv, UART_SSR_OFFS) & UART_SSR_TXFULL) == 0;
}
/****************************************************************************
* Name: up_txempty
*
* Description:
* Return true if the transmit fifo is empty
*
****************************************************************************/
static bool up_txempty(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
return (up_inserial(priv, UART_LSR_OFFS) & UART_LSR_TREF) != 0;
}
/****************************************************************************
* Public Funtions
****************************************************************************/
/****************************************************************************
* Name: up_serialinit
*
* Description:
* Performs the low level UART initialization early in
* debug so that the serial console will be available
* during bootup. This must be called before up_serialinit.
*
****************************************************************************/
void up_earlyserialinit(void)
{
up_disableuartint(TTYS0_DEV.priv, NULL);
up_disableuartint(TTYS1_DEV.priv, NULL);
CONSOLE_DEV.isconsole = true;
up_setup(&CONSOLE_DEV);
}
/****************************************************************************
* Name: up_serialinit
*
* Description:
* Register serial console and serial ports. This assumes
* that up_earlyserialinit was called previously.
*
****************************************************************************/
void up_serialinit(void)
{
(void)uart_register("/dev/console", &CONSOLE_DEV);
(void)uart_register("/dev/ttyS0", &TTYS0_DEV);
(void)uart_register("/dev/ttyS1", &TTYS1_DEV);
}
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug
* writes
*
****************************************************************************/
int up_putc(int ch)
{
struct up_dev_s *priv = (struct up_dev_s*)CONSOLE_DEV.priv;
uint16_t ier;
up_disableuartint(priv, &ier);
up_waittxready(priv);
up_serialout(priv, UART_THR_OFFS, (uint8_t)ch);
/* Check for LF */
if (ch == '\n')
{
/* Add CR */
up_waittxready(priv);
up_serialout(priv, UART_THR_OFFS, '\r');
}
up_waittxready(priv);
up_restoreuartint(priv, ier);
return ch;
}
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