| /* |
| * Copyright (c) 2018 Justin Watson |
| * Copyright (c) 2016 Piotr Mienkowski |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| /** @file |
| * @brief USART driver for Atmel SAM MCU family. |
| * |
| * Note: |
| * - Only basic USART features sufficient to support printf functionality |
| * are currently implemented. |
| */ |
| |
| #include <errno.h> |
| #include <sys/__assert.h> |
| #include <device.h> |
| #include <init.h> |
| #include <soc.h> |
| #include <drivers/uart.h> |
| |
| /* |
| * Verify Kconfig configuration |
| */ |
| |
| #if CONFIG_USART_SAM_PORT_0 == 1 |
| |
| #if DT_USART_SAM_PORT_0_BAUD_RATE == 0 |
| #error "DT_USART_SAM_PORT_0_BAUD_RATE has to be bigger than 0" |
| #endif |
| |
| #endif |
| |
| #if CONFIG_USART_SAM_PORT_1 == 1 |
| |
| #if DT_USART_SAM_PORT_1_BAUD_RATE == 0 |
| #error "DT_USART_SAM_PORT_1_BAUD_RATE has to be bigger than 0" |
| #endif |
| |
| #endif |
| |
| #if CONFIG_USART_SAM_PORT_2 == 1 |
| |
| #if DT_USART_SAM_PORT_2_BAUD_RATE == 0 |
| #error "DT_USART_SAM_PORT_2_BAUD_RATE has to be bigger than 0" |
| #endif |
| |
| #endif |
| |
| /* Device constant configuration parameters */ |
| struct usart_sam_dev_cfg { |
| Usart *regs; |
| u32_t periph_id; |
| struct soc_gpio_pin pin_rx; |
| struct soc_gpio_pin pin_tx; |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| uart_irq_config_func_t irq_config_func; |
| #endif |
| }; |
| |
| /* Device run time data */ |
| struct usart_sam_dev_data { |
| u32_t baud_rate; |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| uart_irq_callback_user_data_t irq_cb; /* Interrupt Callback */ |
| void *cb_data; /* Interrupt Callback Arg */ |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| }; |
| |
| #define DEV_CFG(dev) \ |
| ((const struct usart_sam_dev_cfg *const)(dev)->config->config_info) |
| #define DEV_DATA(dev) \ |
| ((struct usart_sam_dev_data *const)(dev)->driver_data) |
| |
| |
| static int baudrate_set(Usart *const usart, u32_t baudrate, |
| u32_t mck_freq_hz); |
| |
| |
| static int usart_sam_init(struct device *dev) |
| { |
| int retval; |
| const struct usart_sam_dev_cfg *const cfg = DEV_CFG(dev); |
| struct usart_sam_dev_data *const dev_data = DEV_DATA(dev); |
| Usart *const usart = cfg->regs; |
| |
| /* Enable USART clock in PMC */ |
| soc_pmc_peripheral_enable(cfg->periph_id); |
| |
| /* Connect pins to the peripheral */ |
| soc_gpio_configure(&cfg->pin_rx); |
| soc_gpio_configure(&cfg->pin_tx); |
| |
| /* Reset and disable USART */ |
| usart->US_CR = US_CR_RSTRX | US_CR_RSTTX |
| | US_CR_RXDIS | US_CR_TXDIS | US_CR_RSTSTA; |
| |
| /* Disable Interrupts */ |
| usart->US_IDR = 0xFFFFFFFF; |
| |
| /* 8 bits of data, no parity, 1 stop bit in normal mode */ |
| usart->US_MR = US_MR_NBSTOP_1_BIT |
| | US_MR_PAR_NO |
| | US_MR_CHRL_8_BIT |
| | US_MR_USCLKS_MCK |
| | US_MR_CHMODE_NORMAL; |
| |
| /* Set baud rate */ |
| retval = baudrate_set(usart, dev_data->baud_rate, |
| SOC_ATMEL_SAM_MCK_FREQ_HZ); |
| if (retval != 0) { |
| return retval; |
| } |
| |
| /* Enable receiver and transmitter */ |
| usart->US_CR = US_CR_RXEN | US_CR_TXEN; |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| cfg->irq_config_func(dev); |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| return 0; |
| } |
| |
| static int usart_sam_poll_in(struct device *dev, unsigned char *c) |
| { |
| Usart *const usart = DEV_CFG(dev)->regs; |
| |
| if (!(usart->US_CSR & US_CSR_RXRDY)) { |
| return -EBUSY; |
| } |
| |
| /* got a character */ |
| *c = (unsigned char)usart->US_RHR; |
| |
| return 0; |
| } |
| |
| static void usart_sam_poll_out(struct device *dev, unsigned char c) |
| { |
| Usart *const usart = DEV_CFG(dev)->regs; |
| |
| /* Wait for transmitter to be ready */ |
| while (!(usart->US_CSR & US_CSR_TXRDY)) { |
| } |
| |
| /* send a character */ |
| usart->US_THR = (u32_t)c; |
| } |
| |
| static int usart_sam_err_check(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| int errors = 0; |
| |
| if (usart->US_CSR & US_CSR_OVRE) { |
| errors |= UART_ERROR_OVERRUN; |
| } |
| |
| if (usart->US_CSR & US_CSR_PARE) { |
| errors |= UART_ERROR_PARITY; |
| } |
| |
| if (usart->US_CSR & US_CSR_FRAME) { |
| errors |= UART_ERROR_FRAMING; |
| } |
| |
| return errors; |
| } |
| |
| static int baudrate_set(Usart *const usart, u32_t baudrate, |
| u32_t mck_freq_hz) |
| { |
| u32_t divisor; |
| |
| __ASSERT(baudrate, |
| "baud rate has to be bigger than 0"); |
| __ASSERT(mck_freq_hz/16U >= baudrate, |
| "MCK frequency is too small to set required baud rate"); |
| |
| divisor = mck_freq_hz / 16U / baudrate; |
| |
| if (divisor > 0xFFFF) { |
| return -EINVAL; |
| } |
| |
| usart->US_BRGR = US_BRGR_CD(divisor); |
| |
| return 0; |
| } |
| |
| #if CONFIG_UART_INTERRUPT_DRIVEN |
| |
| static int usart_sam_fifo_fill(struct device *dev, const uint8_t *tx_data, |
| int size) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| /* Wait for transmitter to be ready. */ |
| while ((usart->US_CSR & US_CSR_TXRDY) == 0) { |
| } |
| |
| usart->US_THR = *tx_data; |
| |
| return 1; |
| } |
| |
| static int usart_sam_fifo_read(struct device *dev, uint8_t *rx_data, |
| const int size) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| int bytes_read; |
| |
| bytes_read = 0; |
| |
| while (bytes_read < size) { |
| if (usart->US_CSR & US_CSR_RXRDY) { |
| rx_data[bytes_read] = usart->US_RHR; |
| bytes_read++; |
| } else { |
| break; |
| } |
| } |
| |
| return bytes_read; |
| } |
| |
| static void usart_sam_irq_tx_enable(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| usart->US_IER = US_IER_TXRDY; |
| } |
| |
| static void usart_sam_irq_tx_disable(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| usart->US_IDR = US_IDR_TXRDY; |
| } |
| |
| static int usart_sam_irq_tx_ready(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| return (usart->US_CSR & US_CSR_TXRDY); |
| } |
| |
| static void usart_sam_irq_rx_enable(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| usart->US_IER = US_IER_RXRDY; |
| } |
| |
| static void usart_sam_irq_rx_disable(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| usart->US_IDR = US_IDR_RXRDY; |
| } |
| |
| static int usart_sam_irq_tx_complete(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| return !(usart->US_CSR & US_CSR_TXRDY); |
| } |
| |
| static int usart_sam_irq_rx_ready(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| return (usart->US_CSR & US_CSR_RXRDY); |
| } |
| |
| static void usart_sam_irq_err_enable(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| usart->US_IER = US_IER_OVRE | US_IER_FRAME | US_IER_PARE; |
| } |
| |
| static void usart_sam_irq_err_disable(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| usart->US_IDR = US_IDR_OVRE | US_IDR_FRAME | US_IDR_PARE; |
| } |
| |
| static int usart_sam_irq_is_pending(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| return (usart->US_IMR & (US_IMR_TXRDY | US_IMR_RXRDY)) & |
| (usart->US_CSR & (US_CSR_TXRDY | US_CSR_RXRDY)); |
| } |
| |
| static int usart_sam_irq_update(struct device *dev) |
| { |
| volatile Usart * const usart = DEV_CFG(dev)->regs; |
| |
| return (usart->US_CSR & US_CSR_TXEMPTY); |
| } |
| |
| static void usart_sam_irq_callback_set(struct device *dev, |
| uart_irq_callback_user_data_t cb, |
| void *cb_data) |
| { |
| struct usart_sam_dev_data *const dev_data = DEV_DATA(dev); |
| |
| dev_data->irq_cb = cb; |
| dev_data->cb_data = cb_data; |
| } |
| |
| static void usart_sam_isr(void *arg) |
| { |
| struct device *dev = arg; |
| struct usart_sam_dev_data *const dev_data = DEV_DATA(dev); |
| |
| if (dev_data->irq_cb) { |
| dev_data->irq_cb(dev_data->cb_data); |
| } |
| } |
| |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| static const struct uart_driver_api usart_sam_driver_api = { |
| .poll_in = usart_sam_poll_in, |
| .poll_out = usart_sam_poll_out, |
| .err_check = usart_sam_err_check, |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| .fifo_fill = usart_sam_fifo_fill, |
| .fifo_read = usart_sam_fifo_read, |
| .irq_tx_enable = usart_sam_irq_tx_enable, |
| .irq_tx_disable = usart_sam_irq_tx_disable, |
| .irq_tx_ready = usart_sam_irq_tx_ready, |
| .irq_rx_enable = usart_sam_irq_rx_enable, |
| .irq_rx_disable = usart_sam_irq_rx_disable, |
| .irq_tx_complete = usart_sam_irq_tx_complete, |
| .irq_rx_ready = usart_sam_irq_rx_ready, |
| .irq_err_enable = usart_sam_irq_err_enable, |
| .irq_err_disable = usart_sam_irq_err_disable, |
| .irq_is_pending = usart_sam_irq_is_pending, |
| .irq_update = usart_sam_irq_update, |
| .irq_callback_set = usart_sam_irq_callback_set, |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| }; |
| |
| /* USART0 */ |
| |
| #ifdef CONFIG_USART_SAM_PORT_0 |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| /* Forward declare function */ |
| static void usart0_sam_irq_config_func(struct device *port); |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| static const struct usart_sam_dev_cfg usart0_sam_config = { |
| .regs = USART0, |
| .periph_id = DT_USART_SAM_PORT_0_PERIPHERAL_ID, |
| .pin_rx = PIN_USART0_RXD, |
| .pin_tx = PIN_USART0_TXD, |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| .irq_config_func = usart0_sam_irq_config_func, |
| #endif |
| }; |
| |
| static struct usart_sam_dev_data usart0_sam_data = { |
| .baud_rate = DT_USART_SAM_PORT_0_BAUD_RATE, |
| }; |
| |
| DEVICE_AND_API_INIT(usart0_sam, DT_USART_SAM_PORT_0_NAME, &usart_sam_init, |
| &usart0_sam_data, &usart0_sam_config, PRE_KERNEL_1, |
| CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &usart_sam_driver_api); |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| static void usart0_sam_irq_config_func(struct device *port) |
| { |
| IRQ_CONNECT(DT_USART_SAM_PORT_0_IRQ, |
| DT_USART_SAM_PORT_0_IRQ_PRIO, |
| usart_sam_isr, |
| DEVICE_GET(usart0_sam), 0); |
| irq_enable(DT_USART_SAM_PORT_0_IRQ); |
| } |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| #endif |
| |
| /* USART1 */ |
| |
| #ifdef CONFIG_USART_SAM_PORT_1 |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| /* Forward declare function */ |
| static void usart1_sam_irq_config_func(struct device *port); |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| static const struct usart_sam_dev_cfg usart1_sam_config = { |
| .regs = USART1, |
| .periph_id = DT_USART_SAM_PORT_1_PERIPHERAL_ID, |
| .pin_rx = PIN_USART1_RXD, |
| .pin_tx = PIN_USART1_TXD, |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| .irq_config_func = usart1_sam_irq_config_func, |
| #endif |
| }; |
| |
| static struct usart_sam_dev_data usart1_sam_data = { |
| .baud_rate = DT_USART_SAM_PORT_1_BAUD_RATE, |
| }; |
| |
| DEVICE_AND_API_INIT(usart1_sam, DT_USART_SAM_PORT_1_NAME, &usart_sam_init, |
| &usart1_sam_data, &usart1_sam_config, PRE_KERNEL_1, |
| CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &usart_sam_driver_api); |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| static void usart1_sam_irq_config_func(struct device *port) |
| { |
| IRQ_CONNECT(DT_USART_SAM_PORT_1_IRQ, |
| DT_USART_SAM_PORT_1_IRQ_PRIO, |
| usart_sam_isr, |
| DEVICE_GET(usart1_sam), 0); |
| irq_enable(DT_USART_SAM_PORT_1_IRQ); |
| } |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| #endif |
| |
| /* USART2 */ |
| |
| #ifdef CONFIG_USART_SAM_PORT_2 |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| /* Forward declare function */ |
| static void usart2_sam_irq_config_func(struct device *port); |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| static const struct usart_sam_dev_cfg usart2_sam_config = { |
| .regs = USART2, |
| .periph_id = DT_USART_SAM_PORT_2_PERIPHERAL_ID, |
| .pin_rx = PIN_USART2_RXD, |
| .pin_tx = PIN_USART2_TXD, |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| .irq_config_func = usart2_sam_irq_config_func, |
| #endif |
| }; |
| |
| static struct usart_sam_dev_data usart2_sam_data = { |
| .baud_rate = DT_USART_SAM_PORT_2_BAUD_RATE, |
| }; |
| |
| DEVICE_AND_API_INIT(usart2_sam, DT_USART_SAM_PORT_2_NAME, &usart_sam_init, |
| &usart2_sam_data, &usart2_sam_config, PRE_KERNEL_1, |
| CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &usart_sam_driver_api); |
| |
| #ifdef CONFIG_UART_INTERRUPT_DRIVEN |
| static void usart2_sam_irq_config_func(struct device *port) |
| { |
| IRQ_CONNECT(DT_USART_SAM_PORT_2_IRQ, |
| DT_USART_SAM_PORT_2_IRQ_PRIO, |
| usart_sam_isr, |
| DEVICE_GET(usart2_sam), 0); |
| irq_enable(DT_USART_SAM_PORT_2_IRQ); |
| } |
| #endif /* CONFIG_UART_INTERRUPT_DRIVEN */ |
| |
| #endif |