mbed library sources. Supersedes mbed-src.
Fork of mbed-dev by
Diff: targets/TARGET_Maxim/TARGET_MAX32600/serial_api.c
- Revision:
- 149:156823d33999
- Parent:
- 147:30b64687e01f
diff -r 21d94c44109e -r 156823d33999 targets/TARGET_Maxim/TARGET_MAX32600/serial_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_Maxim/TARGET_MAX32600/serial_api.c Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,398 @@ +/******************************************************************************* + * Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES + * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Except as contained in this notice, the name of Maxim Integrated + * Products, Inc. shall not be used except as stated in the Maxim Integrated + * Products, Inc. Branding Policy. + * + * The mere transfer of this software does not imply any licenses + * of trade secrets, proprietary technology, copyrights, patents, + * trademarks, maskwork rights, or any other form of intellectual + * property whatsoever. Maxim Integrated Products, Inc. retains all + * ownership rights. + ******************************************************************************* + */ + +#include <string.h> +#include "mbed_assert.h" +#include "cmsis.h" +#include "serial_api.h" +#include "gpio_api.h" +#include "uart_regs.h" +#include "ioman_regs.h" +#include "PeripheralPins.h" + +#define UART_NUM 2 +#define DEFAULT_BAUD 9600 +#define DEFAULT_STOP 1 +#define DEFAULT_PARITY ParityNone + +#define UART_ERRORS (MXC_F_UART_INTFL_RX_FRAME_ERROR | \ + MXC_F_UART_INTFL_RX_PARITY_ERROR | \ + MXC_F_UART_INTFL_RX_OVERRUN) + +// Variables for managing the stdio UART +int stdio_uart_inited; +serial_t stdio_uart; + +// Variables for interrupt driven +static uart_irq_handler irq_handler; +static uint32_t serial_irq_ids[UART_NUM]; + +//****************************************************************************** +void serial_init(serial_t *obj, PinName tx, PinName rx) +{ + // Determine which uart is associated with each pin + UARTName uart_tx = (UARTName)pinmap_peripheral(tx, PinMap_UART_TX); + UARTName uart_rx = (UARTName)pinmap_peripheral(rx, PinMap_UART_RX); + UARTName uart = (UARTName)pinmap_merge(uart_tx, uart_rx); + + // Make sure that both pins are pointing to the same uart + MBED_ASSERT(uart != (UARTName)NC); + + // Set the obj pointer to the proper uart + obj->uart = (mxc_uart_regs_t*)uart; + + // Set the uart index + obj->index = MXC_UART_BASE_TO_INSTANCE(obj->uart); + + // Configure the pins + pinmap_pinout(tx, PinMap_UART_TX); + pinmap_pinout(rx, PinMap_UART_RX); + + // Flush the RX and TX FIFOs, clear the settings + obj->uart->ctrl = ( MXC_F_UART_CTRL_TX_FIFO_FLUSH | MXC_F_UART_CTRL_RX_FIFO_FLUSH); + + // Disable interrupts + obj->uart->inten = 0; + obj->uart->intfl = 0; + + // Configure to default settings + serial_baud(obj, DEFAULT_BAUD); + serial_format(obj, 8, ParityNone, 1); + + // Manage stdio UART + if(uart == STDIO_UART) { + stdio_uart_inited = 1; + memcpy(&stdio_uart, obj, sizeof(serial_t)); + } +} + +//****************************************************************************** +void serial_baud(serial_t *obj, int baudrate) +{ + uint32_t idiv = 0, ddiv = 0, div = 0; + + // Calculate the integer and decimal portions + div = SystemCoreClock / ((baudrate / 100) * 128); + idiv = (div / 100); + ddiv = (div - idiv * 100) * 128 / 100; + + obj->uart->baud_int = idiv; + obj->uart->baud_div_128 = ddiv; + + // Enable the baud clock + obj->uart->ctrl |= MXC_F_UART_CTRL_BAUD_CLK_EN; +} + +//****************************************************************************** +void serial_format(serial_t *obj, int data_bits, SerialParity parity, int stop_bits) +{ + + // Check the validity of the inputs + MBED_ASSERT((data_bits > 4) && (data_bits < 9)); + MBED_ASSERT((parity == ParityNone) || (parity == ParityOdd) || + (parity == ParityEven) || (parity == ParityForced1) || + (parity == ParityForced0)); + MBED_ASSERT((stop_bits == 1) || (stop_bits == 2)); + + // Adjust the stop and data bits + stop_bits -= 1; + data_bits -= 5; + + // Adjust the parity setting + int paren = 0, mode = 0; + switch (parity) { + case ParityNone: + paren = 0; + mode = 0; + break; + case ParityOdd : + paren = 1; + mode = 0; + break; + case ParityEven: + paren = 1; + mode = 1; + break; + case ParityForced1: + // Hardware does not support forced parity + MBED_ASSERT(0); + break; + case ParityForced0: + // Hardware does not support forced parity + MBED_ASSERT(0); + break; + default: + paren = 1; + mode = 0; + break; + } + + obj->uart->ctrl |= ((data_bits << MXC_F_UART_CTRL_CHAR_LENGTH_POS) | + (stop_bits << MXC_F_UART_CTRL_STOP_BIT_MODE_POS) | + (paren << MXC_F_UART_CTRL_PARITY_ENABLE_POS) | + (mode << MXC_F_UART_CTRL_PARITY_MODE_POS)); +} + +//****************************************************************************** +void uart_handler(mxc_uart_regs_t* uart, int id) +{ + // Check for errors or RX Threshold + if(uart->intfl & (MXC_F_UART_INTFL_RX_OVER_THRESHOLD | UART_ERRORS)) { + irq_handler(serial_irq_ids[id], RxIrq); + uart->intfl &= ~(MXC_F_UART_INTFL_RX_OVER_THRESHOLD | UART_ERRORS); + } + + // Check for TX Threshold + if(uart->intfl & MXC_F_UART_INTFL_TX_ALMOST_EMPTY) { + irq_handler(serial_irq_ids[id], TxIrq); + uart->intfl &= ~(MXC_F_UART_INTFL_TX_ALMOST_EMPTY); + } +} + +void uart0_handler(void) +{ + uart_handler(MXC_UART0, 0); +} +void uart1_handler(void) +{ + uart_handler(MXC_UART1, 1); +} + +//****************************************************************************** +void serial_irq_handler(serial_t *obj, uart_irq_handler handler, uint32_t id) +{ + irq_handler = handler; + serial_irq_ids[obj->index] = id; +} + +//****************************************************************************** +void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable) +{ + if(obj->index == 0) { + NVIC_SetVector(UART0_IRQn, (uint32_t)uart0_handler); + NVIC_EnableIRQ(UART0_IRQn); + } else { + NVIC_SetVector(UART1_IRQn, (uint32_t)uart1_handler); + NVIC_EnableIRQ(UART1_IRQn); + } + + if(irq == RxIrq) { + // Set the RX FIFO Threshold to 1 + obj->uart->ctrl &= ~MXC_F_UART_CTRL_RX_THRESHOLD; + obj->uart->ctrl |= 0x1; + // Enable RX FIFO Threshold Interrupt + if(enable) { + // Clear pending interrupts + obj->uart->intfl = 0; + obj->uart->inten |= (MXC_F_UART_INTFL_RX_OVER_THRESHOLD | + UART_ERRORS); + } else { + // Clear pending interrupts + obj->uart->intfl = 0; + obj->uart->inten &= ~(MXC_F_UART_INTFL_RX_OVER_THRESHOLD | + UART_ERRORS); + } + + } else if (irq == TxIrq) { + // Enable TX Almost empty Interrupt + if(enable) { + // Clear pending interrupts + obj->uart->intfl = 0; + obj->uart->inten |= MXC_F_UART_INTFL_TX_ALMOST_EMPTY; + } else { + // Clear pending interrupts + obj->uart->intfl = 0; + obj->uart->inten &= ~MXC_F_UART_INTFL_TX_ALMOST_EMPTY; + } + + } else { + MBED_ASSERT(0); + } +} + + +//****************************************************************************** +int serial_getc(serial_t *obj) +{ + int c; + + // Wait for data to be available + while(obj->uart->status & MXC_F_UART_STATUS_RX_FIFO_EMPTY) {} + c = obj->uart->tx_rx_fifo & 0xFF; + + return c; +} + +//****************************************************************************** +void serial_putc(serial_t *obj, int c) +{ + // Wait for TXFIFO to not be full + while(obj->uart->status & MXC_F_UART_STATUS_TX_FIFO_FULL) {} + obj->uart->tx_rx_fifo = c; +} + +//****************************************************************************** +int serial_readable(serial_t *obj) +{ + return (!(obj->uart->status & MXC_F_UART_STATUS_RX_FIFO_EMPTY)); +} + +//****************************************************************************** +int serial_writable(serial_t *obj) +{ + return (!(obj->uart->status & MXC_F_UART_STATUS_TX_FIFO_FULL)); +} + +//****************************************************************************** +void serial_clear(serial_t *obj) +{ + // Clear the rx and tx fifos + obj->uart->ctrl |= (MXC_F_UART_CTRL_TX_FIFO_FLUSH | MXC_F_UART_CTRL_RX_FIFO_FLUSH ); +} + +//****************************************************************************** +void serial_break_set(serial_t *obj) +{ + // Make sure that nothing is being sent + while (!(obj->uart->status & MXC_F_UART_STATUS_TX_FIFO_EMPTY)); + while (obj->uart->status & MXC_F_UART_STATUS_TX_BUSY); + + // Configure the GPIO to outpu 0 + gpio_t tx_gpio; + switch (((UARTName)(obj->uart))) { + case UART_0: + gpio_init_out(&tx_gpio, UART0_TX); + break; + case UART_1: + gpio_init_out(&tx_gpio, UART1_TX); + break; + default: + gpio_init_out(&tx_gpio, (PinName)NC); + break; + } + + gpio_write(&tx_gpio, 0); + + // GPIO is setup now, but we need to maps gpio to the pin + switch (((UARTName)(obj->uart))) { + case UART_0: + MXC_IOMAN->uart0_req &= ~MXC_F_IOMAN_UART_CORE_IO; + MBED_ASSERT((MXC_IOMAN->uart0_ack & (MXC_F_IOMAN_UART_CORE_IO | MXC_F_IOMAN_UART_CORE_IO)) == 0); + break; + case UART_1: + MXC_IOMAN->uart1_req &= ~MXC_F_IOMAN_UART_CORE_IO; + MBED_ASSERT((MXC_IOMAN->uart1_ack & (MXC_F_IOMAN_UART_CORE_IO | MXC_F_IOMAN_UART_CORE_IO)) == 0); + break; + default: + break; + } +} + +//****************************************************************************** +void serial_break_clear(serial_t *obj) +{ + // Configure the GPIO to output 1 + gpio_t tx_gpio; + switch (((UARTName)(obj->uart))) { + case UART_0: + gpio_init_out(&tx_gpio, UART0_TX); + break; + case UART_1: + gpio_init_out(&tx_gpio, UART1_TX); + break; + default: + gpio_init_out(&tx_gpio, (PinName)NC); + break; + } + + gpio_write(&tx_gpio, 1); + + // Renable UART + switch (((UARTName)(obj->uart))) { + case UART_0: + serial_pinout_tx(UART0_TX); + break; + case UART_1: + serial_pinout_tx(UART1_TX); + break; + default: + serial_pinout_tx((PinName)NC); + break; + } +} + +//****************************************************************************** +void serial_pinout_tx(PinName tx) +{ + pinmap_pinout(tx, PinMap_UART_TX); +} + + +//****************************************************************************** +void serial_set_flow_control(serial_t *obj, FlowControl type, PinName rxflow, PinName txflow) +{ + if(FlowControlNone == type) { + // Disable hardware flow control + obj->uart->ctrl &= ~(MXC_F_UART_CTRL_HW_FLOW_CTRL_EN); + return; + } + + // Check to see if we can use HW flow control + UARTName uart_cts = (UARTName)pinmap_peripheral(txflow, PinMap_UART_CTS); + UARTName uart_rts = (UARTName)pinmap_peripheral(rxflow, PinMap_UART_RTS); + UARTName uart = (UARTName)pinmap_merge(uart_cts, uart_rts); + + if((FlowControlCTS == type) || (FlowControlRTSCTS== type)) { + // Make sure pin is in the PinMap + MBED_ASSERT(uart_cts != (UARTName)NC); + + // Enable the pin for CTS function + pinmap_pinout(txflow, PinMap_UART_CTS); + } + + if((FlowControlRTS == type) || (FlowControlRTSCTS== type)) { + // Make sure pin is in the PinMap + MBED_ASSERT(uart_rts != (UARTName)NC); + + // Enable the pin for RTS function + pinmap_pinout(rxflow, PinMap_UART_RTS); + } + + if(FlowControlRTSCTS == type){ + // Make sure that the pins are pointing to the same UART + MBED_ASSERT(uart != (UARTName)NC); + } + + // Enable hardware flow control + obj->uart->ctrl |= MXC_F_UART_CTRL_HW_FLOW_CTRL_EN; +}