/**************************************************************************** * arch/avr/src/at90usb/at90usb_serial.c * * Copyright (C) 2011-2012 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include "at90usb_config.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include "up_arch.h" #include "up_internal.h" #include "os_internal.h" #include "at90usb_internal.h" /**************************************************************************** * Definitions ****************************************************************************/ /* Some sanity checks *******************************************************/ /* Is there at least one USART enabled and configured as a RS-232 device? */ #ifndef HAVE_USART_DEVICE # warning "No USARTs enabled as RS-232 devices" #endif /* If we are not using the serial driver for the console, then we still must * provide some minimal implementation of up_putc. */ #ifdef USE_SERIALDRIVER /**************************************************************************** * Private Types ****************************************************************************/ /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static int usart1_setup(struct uart_dev_s *dev); static void usart1_shutdown(struct uart_dev_s *dev); static int usart1_attach(struct uart_dev_s *dev); static void usart1_detach(struct uart_dev_s *dev); static int usart1_rxinterrupt(int irq, void *context); static int usart1_txinterrupt(int irq, void *context); static int usart1_ioctl(struct file *filep, int cmd, unsigned long arg); static int usart1_receive(struct uart_dev_s *dev, FAR unsigned int *status); static void usart1_rxint(struct uart_dev_s *dev, bool enable); static bool usart1_rxavailable(struct uart_dev_s *dev); static void usart1_send(struct uart_dev_s *dev, int ch); static void usart1_txint(struct uart_dev_s *dev, bool enable); static bool usart1_txready(struct uart_dev_s *dev); static bool usart1_txempty(struct uart_dev_s *dev); /**************************************************************************** * Private Variables ****************************************************************************/ struct uart_ops_s g_uart1_ops = {O .setup = usart1_setup, .shutdown = usart1_shutdown, .attach = usart1_attach, .detach = usart1_detach, .ioctl = usart1_ioctl, .receive = usart1_receive, .rxint = usart1_rxint, .rxavailable = usart1_rxavailable, #ifdef CONFIG_SERIAL_IFLOWCONTROL .rxflowcontrol = NULL, #endif .send = usart1_send, .txint = usart1_txint, .txready = usart1_txready, .txempty = usart1_txempty, }; /* I/O buffers */ static char g_usart1rxbuffer[CONFIG_USART1_RXBUFSIZE]; static char g_usart1txbuffer[CONFIG_USART1_TXBUFSIZE]; /* This describes the state of the AT90USB USART1 port. */ static uart_dev_t g_usart1port = { .recv = { .size = CONFIG_USART1_RXBUFSIZE, .buffer = g_usart1rxbuffer, }, .xmit = { .size = CONFIG_USART1_TXBUFSIZE, .buffer = g_usart1txbuffer, }, .ops = &g_uart1_ops, }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: usart1_restoreusartint ****************************************************************************/ static void usart1_restoreusartint(uint8_t imr) { uint8_t regval; regval = UCSR1B; regval &= ~((1 << RXCIE1) | (1 << TXCIE1) | (1 << UDRIE1)); imr &= ((1 << RXCIE1) | (1 << TXCIE1) | (1 << UDRIE1)); regval |= imr; UCSR1B = regval; } /**************************************************************************** * Name: usart1_disableusartint ****************************************************************************/ static inline void usart1_disableusartint(uint8_t *imr) { uint8_t regval; regval = UCSR1B; *imr = regval; regval &= ~((1 << RXCIE1) | (1 << TXCIE1) | (1 << UDRIE1)); UCSR1B = regval; } /**************************************************************************** * Name: usart1_setup * * Description: * Configure the USART baud, bits, parity, etc. This method is called the * first time that the serial port is opened. * ****************************************************************************/ static int usart1_setup(struct uart_dev_s *dev) { #ifndef CONFIG_SUPPRESS_UART_CONFIG /* Configure the USART1 */ usart1_configure(); #endif return OK; } /**************************************************************************** * Name: usart1_shutdown * * Description: * Disable the USART. This method is called when the serial * port is closed * ****************************************************************************/ static void usart1_shutdown(struct uart_dev_s *dev) { /* Reset, disable interrupts, and disable Rx and Tx */ usart1_reset(); } /**************************************************************************** * Name: usart1_attach * * Description: * Configure the USART 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 usart1_attach(struct uart_dev_s *dev) { /* Attach the USART1 IRQs: * * RX: USART Receive Complete. Set when are unread data in the receive * buffer and cleared when the receive buffer is empty. * TX: USART Transmit Complete. Set when the entire frame in the Transmit * Shift Register has been shifted out and there are no new data * currently present in the transmit buffer. * DRE: USART Data Register Empty. Indicates if the transmit buffer is ready * to receive new data: The buffer is empty, and therefore ready to be * written. */ (void)irq_attach(AT90USB_IRQ_U1RX, usart1_rxinterrupt); (void)irq_attach(AT90USB_IRQ_U1DRE, usart1_txinterrupt); // (void)irq_attach(AT90USB_IRQ_U1TX, usart1_txinterrupt); return OK; } /**************************************************************************** * Name: usart1_detach * * Description: * Detach USART 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 usart1_detach(struct uart_dev_s *dev) { /* Disable USART1 interrupts */ usart1_disableusartint(NULL); /* Detach USART1 interrupts */ (void)irq_detach(AT90USB_IRQ_U1RX); (void)irq_detach(AT90USB_IRQ_U1DRE); // (void)irq_detach(AT90USB_IRQ_U1TX); } /**************************************************************************** * Name: usart1_rxinterrupt * * Description: * This is the USART RX interrupt handler. It will be invoked when an * RX interrupt received. It will call uart_receivechar to perform the RX * data transfers. * ****************************************************************************/ static int usart1_rxinterrupt(int irq, void *context) { uint8_t ucsr1a = UCSR1A; /* Handle incoming, receive bytes (with or without timeout) */ if ((ucsr1a & (1 << RXC1)) != 0) { /* Received data ready... process incoming bytes */ uart_recvchars(&g_usart1port); } return OK; } /**************************************************************************** * Name: usart1_txinterrupt * * Description: * This is the USART TX interrupt handler. It will be invoked when an * TX or DRE interrupt received. It will call uart_xmitchars to perform * the TXdata transfers. * ****************************************************************************/ static int usart1_txinterrupt(int irq, void *context) { uint8_t ucsr1a = UCSR1A; /* Handle outgoing, transmit bytes when the transmit data buffer is empty. * (There may still be data in the shift register). */ if ((ucsr1a & (1 << UDRE1)) != 0) { /* Transmit data regiser empty ... process outgoing bytes */ uart_xmitchars(&g_usart1port); } return OK; } /**************************************************************************** * Name: usart1_ioctl * * Description: * All ioctl calls will be routed through this method * ****************************************************************************/ static int usart1_ioctl(struct file *filep, int cmd, unsigned long arg) { #if 0 /* Reserved for future growth */ int ret = OK; switch (cmd) { case xxx: /* Add commands here */ break; default: ret = -ENOTTY; break; } return ret; #else return -ENOTTY; #endif } /**************************************************************************** * Name: usart1_receive * * Description: * Called (usually) from the interrupt level to receive one * character from the USART. Error bits associated with the * receipt are provided in the return 'status'. * ****************************************************************************/ static int usart1_receive(struct uart_dev_s *dev, FAR unsigned int *status) { /* Return status information (error bits will be cleared after reading UDR1) */ if (status) { *status = (FAR unsigned int)UCSR1A; } /* Then return the actual received byte */ return UDR1; } /**************************************************************************** * Name: usart1_rxint * * Description: * Call to enable or disable RX interrupts * ****************************************************************************/ static void usart1_rxint(struct uart_dev_s *dev, bool enable) { /* Enable/disable RX interrupts: * * RX: USART Receive Complete. Set when are unread data in the receive * buffer and cleared when the receive buffer is empty. */ if (enable) { #ifndef CONFIG_SUPPRESS_SERIAL_INTS UCSR1B |= (1 << RXCIE1); #endif } else { UCSR1B &= ~(1 << RXCIE1); } } /**************************************************************************** * Name: usart1_rxavailable * * Description: * Return true if the receive register is not empty * ****************************************************************************/ static bool usart1_rxavailable(struct uart_dev_s *dev) { return (UCSR1A & (1 << RXC1)) != 0; } /**************************************************************************** * Name: usart1_send * * Description: * This method will send one byte on the USART. * ****************************************************************************/ static void usart1_send(struct uart_dev_s *dev, int ch) { UDR1 = ch; } /**************************************************************************** * Name: usart1_txint * * Description: * Call to enable or disable TX interrupts * ****************************************************************************/ static void usart1_txint(struct uart_dev_s *dev, bool enable) { irqstate_t flags; /* Enable/disable TX interrupts: * * TX: USART Transmit Complete. Set when the entire frame in the Transmit * Shift Register has been shifted out and there are no new data * currently present in the transmit buffer. * DRE: USART Data Register Empty. Indicates if the transmit buffer is ready * to receive new data: The buffer is empty, and therefore ready to be * written. */ flags = irqsave(); if (enable) { /* Set to receive an interrupt when the TX data register is empty */ #ifndef CONFIG_SUPPRESS_SERIAL_INTS UCSR1B |= (1 << UDRIE1); // UCSR1B |= (1 << TXCIE1); /* Fake a TX interrupt here by just calling uart_xmitchars() with * interrupts disabled (note this may recurse). */ uart_xmitchars(&g_usart1port); #endif } else { /* Disable the TX interrupt */ UCSR1B &= ~((1 << UDRIE1) | (1 << TXCIE1)); } irqrestore(flags); } /**************************************************************************** * Name: usart1_txready * * Description: * Return true if the tranmsit data register is empty * ****************************************************************************/ static bool usart1_txready(struct uart_dev_s *dev) { return (UCSR1A & (1 << UDRE1)) != 0; } /**************************************************************************** * Name: usart1_txempty * * Description: * Return true if the tranmsit data register and shift register are both * empty * ****************************************************************************/ static bool usart1_txempty(struct uart_dev_s *dev) { return (UCSR1A & (1 << TXC1)) != 0; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: up_earlyserialinit * * Description: * Performs the low level USART 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) { /* Disable all USARTS */ usart1_disableusartint(NULL); /* Configuration whichever one is the console */ #ifdef HAVE_SERIAL_CONSOLE g_usart1port.isconsole = true; usart1_setup(&g_usart1port); #endif } /**************************************************************************** * Name: up_serialinit * * Description: * Register serial console and serial ports. This assumes * that up_earlyserialinit was called previously. * ****************************************************************************/ void up_serialinit(void) { /* Register the console */ #ifdef HAVE_SERIAL_CONSOLE (void)uart_register("/dev/console", &g_usart1port); #endif /* Register all USARTs */ (void)uart_register("/dev/ttyS0", &g_usart1port); } /**************************************************************************** * Name: up_putc * * Description: * Provide priority, low-level access to support OS debug writes * ****************************************************************************/ int up_putc(int ch) { #ifdef HAVE_SERIAL_CONSOLE uint8_t imr; usart1_disableusartint(&imr); /* Check for LF */ if (ch == '\n') { /* Add CR */ up_lowputc('\r'); } up_lowputc(ch); usart1_restoreusartint(imr); #endif return ch; } #else /* USE_SERIALDRIVER */ /**************************************************************************** * Name: up_putc * * Description: * Provide priority, low-level access to support OS debug writes * ****************************************************************************/ int up_putc(int ch) { #ifdef HAVE_SERIAL_CONSOLE /* Check for LF */ if (ch == '\n') { /* Add CR */ up_lowputc('\r'); } up_lowputc(ch); #endif return ch; } #endif /* USE_SERIALDRIVER */