text: /*
   * Copyright (c) 2017, NXP
   *
   * SPDX-License-Identifier: Apache-2.0
   */
  
  #define DT_DRV_COMPAT nxp_kinetis_lpsci
  
  #include <errno.h>
  #include <device.h>
  #include <drivers/uart.h>
  #include <drivers/clock_control.h>
  #include <fsl_lpsci.h>
  #include <soc.h>
  
  struct mcux_lpsci_config {
  	UART0_Type *base;
  	char *clock_name;
  	clock_control_subsys_t clock_subsys;
  	uint32_t baud_rate;
  #ifdef CONFIG_UART_INTERRUPT_DRIVEN
  	void (*irq_config_func)(struct device *dev);
  #endif
  };
  
  struct mcux_lpsci_data {
  #ifdef CONFIG_UART_INTERRUPT_DRIVEN
  	uart_irq_callback_user_data_t callback;
  	void *cb_data;
  #endif
  };
  
  static int mcux_lpsci_poll_in(struct device *dev, unsigned char *c)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t flags = LPSCI_GetStatusFlags(config->base);
  	int ret = -1;
  
  	if (flags & kLPSCI_RxDataRegFullFlag) {
  		*c = LPSCI_ReadByte(config->base);
  		ret = 0;
  	}
  
  	return ret;
  }
  
  static void mcux_lpsci_poll_out(struct device *dev, unsigned char c)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  
  	while (!(LPSCI_GetStatusFlags(config->base)
  		& kLPSCI_TxDataRegEmptyFlag)) {
  	}
  
  	LPSCI_WriteByte(config->base, c);
  }
  
  static int mcux_lpsci_err_check(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t flags = LPSCI_GetStatusFlags(config->base);
  	int err = 0;
  
  	if (flags & kLPSCI_RxOverrunFlag) {
  		err |= UART_ERROR_OVERRUN;
  	}
  
  	if (flags & kLPSCI_ParityErrorFlag) {
  		err |= UART_ERROR_PARITY;
  	}
  
  	if (flags & kLPSCI_FramingErrorFlag) {
  		err |= UART_ERROR_FRAMING;
  	}
  
  	LPSCI_ClearStatusFlags(config->base, kLPSCI_RxOverrunFlag |
  					      kLPSCI_ParityErrorFlag |
  					      kLPSCI_FramingErrorFlag);
  
  	return err;
  }
  
  #ifdef CONFIG_UART_INTERRUPT_DRIVEN
  static int mcux_lpsci_fifo_fill(struct device *dev, const uint8_t *tx_data,
  				int len)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint8_t num_tx = 0U;
  
  	while ((len - num_tx > 0) &&
  	       (LPSCI_GetStatusFlags(config->base)
  		& kLPSCI_TxDataRegEmptyFlag)) {
  
  		LPSCI_WriteByte(config->base, tx_data[num_tx++]);
  	}
  
  	return num_tx;
  }
  
  static int mcux_lpsci_fifo_read(struct device *dev, uint8_t *rx_data,
  				const int len)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint8_t num_rx = 0U;
  
  	while ((len - num_rx > 0) &&
  	       (LPSCI_GetStatusFlags(config->base)
  		& kLPSCI_RxDataRegFullFlag)) {
  
  		rx_data[num_rx++] = LPSCI_ReadByte(config->base);
  	}
  
  	return num_rx;
  }
  
  static void mcux_lpsci_irq_tx_enable(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_TxDataRegEmptyInterruptEnable;
  
  	LPSCI_EnableInterrupts(config->base, mask);
  }
  
  static void mcux_lpsci_irq_tx_disable(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_TxDataRegEmptyInterruptEnable;
  
  	LPSCI_DisableInterrupts(config->base, mask);
  }
  
  static int mcux_lpsci_irq_tx_complete(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t flags = LPSCI_GetStatusFlags(config->base);
  
  	return (flags & kLPSCI_TransmissionCompleteFlag) != 0U;
  }
  
  static int mcux_lpsci_irq_tx_ready(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_TxDataRegEmptyInterruptEnable;
  	uint32_t flags = LPSCI_GetStatusFlags(config->base);
  
  	return (LPSCI_GetEnabledInterrupts(config->base) & mask)
  		&& (flags & kLPSCI_TxDataRegEmptyFlag);
  }
  
  static void mcux_lpsci_irq_rx_enable(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_RxDataRegFullInterruptEnable;
  
  	LPSCI_EnableInterrupts(config->base, mask);
  }
  
  static void mcux_lpsci_irq_rx_disable(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_RxDataRegFullInterruptEnable;
  
  	LPSCI_DisableInterrupts(config->base, mask);
  }
  
  static int mcux_lpsci_irq_rx_full(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t flags = LPSCI_GetStatusFlags(config->base);
  
  	return (flags & kLPSCI_RxDataRegFullFlag) != 0U;
  }
  
  static int mcux_lpsci_irq_rx_ready(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_RxDataRegFullInterruptEnable;
  
  	return (LPSCI_GetEnabledInterrupts(config->base) & mask)
  		&& mcux_lpsci_irq_rx_full(dev);
  }
  
  static void mcux_lpsci_irq_err_enable(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_NoiseErrorInterruptEnable |
  			kLPSCI_FramingErrorInterruptEnable |
  			kLPSCI_ParityErrorInterruptEnable;
  
  	LPSCI_EnableInterrupts(config->base, mask);
  }
  
  static void mcux_lpsci_irq_err_disable(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	uint32_t mask = kLPSCI_NoiseErrorInterruptEnable |
  			kLPSCI_FramingErrorInterruptEnable |
  			kLPSCI_ParityErrorInterruptEnable;
  
  	LPSCI_DisableInterrupts(config->base, mask);
  }
  
  static int mcux_lpsci_irq_is_pending(struct device *dev)
  {
  	return (mcux_lpsci_irq_tx_ready(dev)
  		|| mcux_lpsci_irq_rx_ready(dev));
  }
  
  static int mcux_lpsci_irq_update(struct device *dev)
  {
  	return 1;
  }
  
  static void mcux_lpsci_irq_callback_set(struct device *dev,
  				       uart_irq_callback_user_data_t cb,
  				       void *cb_data)
  {
  	struct mcux_lpsci_data *data = dev->driver_data;
  
  	data->callback = cb;
  	data->cb_data = cb_data;
  }
  
  static void mcux_lpsci_isr(void *arg)
  {
  	struct device *dev = arg;
  	struct mcux_lpsci_data *data = dev->driver_data;
  
  	if (data->callback) {
  		data->callback(data->cb_data);
  	}
  }
  #endif /* CONFIG_UART_INTERRUPT_DRIVEN */
  
  static int mcux_lpsci_init(struct device *dev)
  {
  	const struct mcux_lpsci_config *config = dev->config_info;
  	lpsci_config_t uart_config;
  	struct device *clock_dev;
  	uint32_t clock_freq;
  
  	clock_dev = device_get_binding(config->clock_name);
  	if (clock_dev == NULL) {
  		return -EINVAL;
  	}
  
  	if (clock_control_get_rate(clock_dev, config->clock_subsys,
  				   &clock_freq)) {
  		return -EINVAL;
  	}
  
  	LPSCI_GetDefaultConfig(&uart_config);
  	uart_config.enableTx = true;
  	uart_config.enableRx = true;
  	uart_config.baudRate_Bps = config->baud_rate;
  
  	LPSCI_Init(config->base, &uart_config, clock_freq);
  
  #ifdef CONFIG_UART_INTERRUPT_DRIVEN
  	config->irq_config_func(dev);
  #endif
  
  	return 0;
  }
  
  static const struct uart_driver_api mcux_lpsci_driver_api = {
  	.poll_in = mcux_lpsci_poll_in,
  	.poll_out = mcux_lpsci_poll_out,
  	.err_check = mcux_lpsci_err_check,
  #ifdef CONFIG_UART_INTERRUPT_DRIVEN
  	.fifo_fill = mcux_lpsci_fifo_fill,
  	.fifo_read = mcux_lpsci_fifo_read,
  	.irq_tx_enable = mcux_lpsci_irq_tx_enable,
  	.irq_tx_disable = mcux_lpsci_irq_tx_disable,
  	.irq_tx_complete = mcux_lpsci_irq_tx_complete,
  	.irq_tx_ready = mcux_lpsci_irq_tx_ready,
  	.irq_rx_enable = mcux_lpsci_irq_rx_enable,
  	.irq_rx_disable = mcux_lpsci_irq_rx_disable,
  	.irq_rx_ready = mcux_lpsci_irq_rx_ready,
  	.irq_err_enable = mcux_lpsci_irq_err_enable,
  	.irq_err_disable = mcux_lpsci_irq_err_disable,
  	.irq_is_pending = mcux_lpsci_irq_is_pending,
  	.irq_update = mcux_lpsci_irq_update,
  	.irq_callback_set = mcux_lpsci_irq_callback_set,
  #endif
  };
  
  #ifdef CONFIG_UART_INTERRUPT_DRIVEN
  #define MCUX_LPSCI_CONFIG_FUNC(n)					\
  	static void mcux_lpsci_config_func_##n(struct device *dev)	\
  	{								\
  		IRQ_CONNECT(DT_INST_IRQN(n),				\
  			    DT_INST_IRQ(n, priority),			\
  			    mcux_lpsci_isr, DEVICE_GET(uart_##n), 0);	\
  									\
  		irq_enable(DT_INST_IRQN(n));				\
  	}
  #define MCUX_LPSCI_IRQ_CFG_FUNC_INIT(n)					\
  	.irq_config_func = mcux_lpsci_config_func_##n
  #define MCUX_LPSCI_INIT_CFG(n)						\
  	MCUX_LPSCI_DECLARE_CFG(n, MCUX_LPSCI_IRQ_CFG_FUNC_INIT(n))
  #else
  #define MCUX_LPSCI_CONFIG_FUNC(n)
  #define MCUX_LPSCI_IRQ_CFG_FUNC_INIT
  #define MCUX_LPSCI_INIT_CFG(n)						\
  	MCUX_LPSCI_DECLARE_CFG(n, MCUX_LPSCI_IRQ_CFG_FUNC_INIT)
  #endif
  
  #define MCUX_LPSCI_DECLARE_CFG(n, IRQ_FUNC_INIT)			\
  static const struct mcux_lpsci_config mcux_lpsci_##n##_config = {	\
  	.base = (UART0_Type *)DT_INST_REG_ADDR(n),			\
  	.clock_name = DT_INST_CLOCKS_LABEL(n),				\
  	.clock_subsys = (clock_control_subsys_t)DT_INST_CLOCKS_CELL(n, name),\
  	.baud_rate = DT_INST_PROP(n, current_speed),			\
  	IRQ_FUNC_INIT							\
  }
  
  #define MCUX_LPSCI_INIT(n)						\
  									\
  	static struct mcux_lpsci_data mcux_lpsci_##n##_data;		\
  									\
  	static const struct mcux_lpsci_config mcux_lpsci_##n##_config;	\
  									\
  	DEVICE_AND_API_INIT(uart_##n, DT_INST_LABEL(n),			\
  			    &mcux_lpsci_init,				\
  			    &mcux_lpsci_##n##_data,			\
  			    &mcux_lpsci_##n##_config,			\
  			    PRE_KERNEL_1,				\
  			    CONFIG_KERNEL_INIT_PRIORITY_DEVICE,		\
  			    &mcux_lpsci_driver_api);			\
  									\
  	MCUX_LPSCI_CONFIG_FUNC(n)					\
  									\
  	MCUX_LPSCI_INIT_CFG(n);
  
  DT_INST_FOREACH_STATUS_OKAY(MCUX_LPSCI_INIT)
  