[PATCH 14/15] tty: serial: Add Nuvoton ma35d1 serial driver support
From: Jacky Huang
Date: Wed Mar 15 2023 - 03:32:47 EST
From: Jacky Huang <ychuang3@xxxxxxxxxxx>
This adds UART and console driver for Nuvoton ma35d1 Soc.
MA35D1 SoC provides up to 17 UART controllers, each with one uart port.
The ma35d1 uart controller is not compatible with 8250.
The uart controller supports:
- Full-duplex asynchronous communications
- Separates tx and tx 32/32 bytes entry FIFO for data payloads
- Hardware auto-flow control
- Programmable rx buffer trigger level (1/4/8/14/30 bytes)
- Individual programmable baud rate generator for each channel
- Supports nCTS, incoming data, rx FIFO reached threshold and
RS-485 Address Match (AAD mode) wake-up function
- Supports 8-bit rx buffer time-out detection function
- Programmable tx data delay time
- Supports Auto-Baud Rate measurement and baud rate compensation
- Supports break error, frame error, parity error and rx/tx buffer
overflow detection function
– Programmable number of data bit, 5-, 6-, 7-, 8- bit character
– Programmable parity bit, even, odd, no parity or stick parity bit
generation and detection
– Programmable stop bit, 1, 1.5, or 2 stop bit generation
- Supports IrDA SIR function mode
- Supports RS-485 function mode
– Supports RS-485 9-bit mode
– Supports hardware or software enables to program nRTS pin to control
RS-485 transmission direction
- Supports PDMA transfer function
- Support Single-wire function mode.
Signed-off-by: Jacky Huang <ychuang3@xxxxxxxxxxx>
---
drivers/tty/serial/Kconfig | 18 +
drivers/tty/serial/Makefile | 1 +
drivers/tty/serial/ma35d1_serial.c | 842 +++++++++++++++++++++++++++++
drivers/tty/serial/ma35d1_serial.h | 93 ++++
include/uapi/linux/serial_core.h | 3 +
5 files changed, 957 insertions(+)
create mode 100644 drivers/tty/serial/ma35d1_serial.c
create mode 100644 drivers/tty/serial/ma35d1_serial.h
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 625358f44419..cb47fe804595 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1562,6 +1562,24 @@ config SERIAL_SUNPLUS_CONSOLE
you can alter that using a kernel command line option such as
"console=ttySUPx".
+config SERIAL_NUVOTON_MA35D1
+ tristate "Nuvoton MA35D1 family UART support"
+ depends on ARCH_NUVOTON || COMPILE_TEST
+ select SERIAL_CORE
+ help
+ This driver supports Nuvoton MA35D1 family UART ports. If you would
+ like to use them, you must answer Y or M to this option. Note that
+ for use as console, it must be included in kernel and not as a
+ module
+
+config SERIAL_NUVOTON_MA35D1_CONSOLE
+ bool "Console on a Nuvotn MA35D1 family UART port"
+ depends on SERIAL_NUVOTON_MA35D1=y
+ select SERIAL_CORE_CONSOLE
+ help
+ Select this options if you'd like to use the UART port0 of the
+ Nuvoton MA35D1 family as a console.
+
endmenu
config SERIAL_MCTRL_GPIO
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index cd9afd9e3018..71ebeba06ff2 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -93,3 +93,4 @@ obj-$(CONFIG_SERIAL_MCTRL_GPIO) += serial_mctrl_gpio.o
obj-$(CONFIG_SERIAL_KGDB_NMI) += kgdb_nmi.o
obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o
+obj-$(CONFIG_SERIAL_NUVOTON_MA35D1) += ma35d1_serial.o
diff --git a/drivers/tty/serial/ma35d1_serial.c b/drivers/tty/serial/ma35d1_serial.c
new file mode 100644
index 000000000000..8940d07c3777
--- /dev/null
+++ b/drivers/tty/serial/ma35d1_serial.c
@@ -0,0 +1,842 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MA35D1 serial driver
+ * Copyright (C) 2023 Nuvoton Technology Corp.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/clk.h>
+#include <linux/serial_reg.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/nmi.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/io.h>
+#include <asm/irq.h>
+#include <asm/serial.h>
+#include "ma35d1_serial.h"
+
+#define UART_NR 17
+
+static struct uart_driver ma35d1serial_reg;
+struct clk *clk;
+
+struct uart_ma35d1_port {
+ struct uart_port port;
+ u16 capabilities; /* port capabilities */
+ u8 ier;
+ u8 lcr;
+ u8 mcr;
+ u8 mcr_mask; /* mask of user bits */
+ u8 mcr_force; /* mask of forced bits */
+ struct serial_rs485 rs485; /* rs485 settings */
+ u32 baud_rate;
+ int rx_count;
+ u32 console_baud_rate;
+ u32 console_line;
+ u32 console_int;
+};
+
+static struct device_node *ma35d1serial_uart_nodes[UART_NR];
+static struct uart_ma35d1_port ma35d1serial_ports[UART_NR] = { 0 };
+static void __stop_tx(struct uart_ma35d1_port *p);
+static void transmit_chars(struct uart_ma35d1_port *up);
+
+static struct uart_ma35d1_port *to_ma35d1_uart_port(struct uart_port *uart)
+{
+ return container_of(uart, struct uart_ma35d1_port, port);
+}
+
+static u32 serial_in(struct uart_ma35d1_port *p, int offset)
+{
+ return __raw_readl(p->port.membase + offset);
+}
+
+static void serial_out(struct uart_ma35d1_port *p, int offset, int value)
+{
+ __raw_writel(value, p->port.membase + offset);
+}
+
+static void __stop_tx(struct uart_ma35d1_port *p)
+{
+ u32 ier;
+
+ ier = serial_in(p, UART_REG_IER);
+ if (ier & THRE_IEN)
+ serial_out(p, UART_REG_IER, ier & ~THRE_IEN);
+}
+
+static void ma35d1serial_stop_tx(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+
+ __stop_tx(up);
+}
+
+static void ma35d1serial_start_tx(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ u32 ier;
+ struct circ_buf *xmit = &up->port.state->xmit;
+
+ ier = serial_in(up, UART_REG_IER);
+ serial_out(up, UART_REG_IER, ier & ~THRE_IEN);
+ if (uart_circ_chars_pending(xmit) <
+ (16 - ((serial_in(up, UART_REG_FSR) >> 16) & 0x3F)))
+ transmit_chars(up);
+ serial_out(up, UART_REG_IER, ier | THRE_IEN);
+}
+
+static void ma35d1serial_stop_rx(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+
+ serial_out(up, UART_REG_IER, serial_in(up, UART_REG_IER) & ~RDA_IEN);
+}
+
+static void
+receive_chars(struct uart_ma35d1_port *up)
+{
+ u8 ch;
+ u32 fsr;
+ u32 isr;
+ u32 dcnt;
+ char flag;
+
+ isr = serial_in(up, UART_REG_ISR);
+ fsr = serial_in(up, UART_REG_FSR);
+
+ while (!(fsr & RX_EMPTY)) {
+ flag = TTY_NORMAL;
+ up->port.icount.rx++;
+
+ if (unlikely(fsr & (BIF | FEF | PEF | RX_OVER_IF))) {
+ if (fsr & BIF) {
+ serial_out(up, UART_REG_FSR, BIF);
+ up->port.icount.brk++;
+ if (uart_handle_break(&up->port))
+ continue;
+ }
+ if (fsr & FEF) {
+ serial_out(up, UART_REG_FSR, FEF);
+ up->port.icount.frame++;
+ }
+ if (fsr & PEF) {
+ serial_out(up, UART_REG_FSR, PEF);
+ up->port.icount.parity++;
+ }
+ if (fsr & RX_OVER_IF) {
+ serial_out(up, UART_REG_FSR, RX_OVER_IF);
+ up->port.icount.overrun++;
+ }
+ if (fsr & BIF)
+ flag = TTY_BREAK;
+ if (fsr & PEF)
+ flag = TTY_PARITY;
+ if (fsr & FEF)
+ flag = TTY_FRAME;
+ }
+ ch = (u8)serial_in(up, UART_REG_RBR);
+ if (uart_handle_sysrq_char(&up->port, ch))
+ continue;
+
+ uart_insert_char(&up->port, fsr, RX_OVER_IF, ch, flag);
+ up->rx_count++;
+ dcnt = (serial_in(up, UART_REG_FSR) >> 8) & 0x3f;
+ if (up->rx_count > 1023) {
+ spin_lock(&up->port.lock);
+ tty_flip_buffer_push(&up->port.state->port);
+ spin_unlock(&up->port.lock);
+ up->rx_count = 0;
+ if ((isr & RXTO_IF) && (dcnt == 0))
+ goto tout_end;
+ }
+ if (isr & RDA_IF) {
+ if (dcnt == 1)
+ return;
+ }
+ fsr = serial_in(up, UART_REG_FSR);
+ }
+ spin_lock(&up->port.lock);
+ tty_flip_buffer_push(&up->port.state->port);
+ spin_unlock(&up->port.lock);
+tout_end:
+ up->rx_count = 0;
+}
+
+static void transmit_chars(struct uart_ma35d1_port *up)
+{
+ struct circ_buf *xmit = &up->port.state->xmit;
+ int count = 16 - ((serial_in(up, UART_REG_FSR) >> 16) & 0xF);
+
+ if (serial_in(up, UART_REG_FSR) & TX_FULL)
+ count = 0;
+ if (up->port.x_char) {
+ serial_out(up, UART_REG_THR, up->port.x_char);
+ up->port.icount.tx++;
+ up->port.x_char = 0;
+ return;
+ }
+ if (uart_tx_stopped(&up->port)) {
+ ma35d1serial_stop_tx(&up->port);
+ return;
+ }
+ if (uart_circ_empty(xmit)) {
+ __stop_tx(up);
+ return;
+ }
+ while (count > 0) {
+ serial_out(up, UART_REG_THR, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ up->port.icount.tx++;
+ count--;
+ if (uart_circ_empty(xmit))
+ break;
+ }
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&up->port);
+ if (uart_circ_empty(xmit))
+ __stop_tx(up);
+}
+
+static irqreturn_t ma35d1serial_interrupt(int irq, void *dev_id)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)dev_id;
+ u32 isr, fsr;
+
+ isr = serial_in(up, UART_REG_ISR);
+ fsr = serial_in(up, UART_REG_FSR);
+ if (isr & (RDA_IF | RXTO_IF))
+ receive_chars(up);
+ if (isr & THRE_INT)
+ transmit_chars(up);
+ if (fsr & (BIF | FEF | PEF | RX_OVER_IF | TX_OVER_IF))
+ serial_out(up, UART_REG_FSR,
+ (BIF | FEF | PEF | RX_OVER_IF | TX_OVER_IF));
+
+ return IRQ_HANDLED;
+}
+
+static u32 ma35d1serial_tx_empty(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ u32 fsr;
+
+ fsr = serial_in(up, UART_REG_FSR);
+ return (fsr & (TE_FLAG | TX_EMPTY)) == (TE_FLAG | TX_EMPTY) ?
+ TIOCSER_TEMT : 0;
+}
+
+static u32 ma35d1serial_get_mctrl(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ u32 status;
+ u32 ret = 0;
+
+ status = serial_in(up, UART_REG_MSR);
+ if (!(status & 0x10))
+ ret |= TIOCM_CTS;
+ return ret;
+}
+
+static void ma35d1serial_set_mctrl(struct uart_port *port, u32 mctrl)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ u32 mcr = 0;
+ u32 ier = 0;
+
+ if (mctrl & TIOCM_RTS) {
+ /* set RTS high level trigger */
+ mcr = serial_in(up, UART_REG_MCR);
+ mcr |= 0x200;
+ mcr &= ~(0x2);
+ }
+ if (up->mcr & UART_MCR_AFE) {
+ /* set RTS high level trigger */
+ mcr = serial_in(up, UART_REG_MCR);
+ mcr |= 0x200;
+ mcr &= ~(0x2);
+
+ /* enable CTS/RTS auto-flow control */
+ serial_out(up, UART_REG_IER,
+ (serial_in(up, UART_REG_IER) | (0x3000)));
+
+ /* Set hardware flow control */
+ up->port.flags |= UPF_HARD_FLOW;
+ } else {
+ /* disable CTS/RTS auto-flow control */
+ ier = serial_in(up, UART_REG_IER);
+ ier &= ~(0x3000);
+ serial_out(up, UART_REG_IER, ier);
+
+ /* un-set hardware flow control */
+ up->port.flags &= ~UPF_HARD_FLOW;
+ }
+
+ /* set CTS high level trigger */
+ serial_out(up, UART_REG_MSR, (serial_in(up, UART_REG_MSR) | (0x100)));
+ serial_out(up, UART_REG_MCR, mcr);
+}
+
+static void ma35d1serial_break_ctl(struct uart_port *port, int break_state)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ unsigned long flags;
+ u32 lcr;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ lcr = serial_in(up, UART_REG_LCR);
+ if (break_state != 0)
+ lcr |= BCB; /* set break */
+ else
+ lcr &= ~BCB; /* clr break */
+ serial_out(up, UART_REG_LCR, lcr);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static int ma35d1serial_startup(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ struct tty_struct *tty = port->state->port.tty;
+ int retval;
+
+ /* Reset FIFO */
+ serial_out(up, UART_REG_FCR, TFR | RFR /* | RX_DIS */);
+
+ /* Clear pending interrupts */
+ serial_out(up, UART_REG_ISR, 0xFFFFFFFF);
+
+ retval = request_irq(port->irq, ma35d1serial_interrupt, 0,
+ tty ? tty->name : "ma35d1_serial", port);
+ if (retval) {
+ dev_err(up->port.dev, "request irq failed.\n");
+ return retval;
+ }
+
+ /* Now, initialize the UART */
+ /* FIFO trigger level 4 byte */
+ /* RTS trigger level 8 bytes */
+ serial_out(up, UART_REG_FCR,
+ serial_in(up, UART_REG_FCR) | 0x10 | 0x20000);
+ serial_out(up, UART_REG_LCR, 0x7); /* 8 bit */
+ serial_out(up, UART_REG_TOR, 0x40);
+ serial_out(up, UART_REG_IER,
+ RTO_IEN | RDA_IEN | TIME_OUT_EN | BUFERR_IEN);
+ return 0;
+}
+
+static void ma35d1serial_shutdown(struct uart_port *port)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+
+ free_irq(port->irq, port);
+
+ /* Disable interrupts from this port */
+ serial_out(up, UART_REG_IER, 0);
+}
+
+static u32 ma35d1serial_get_divisor(struct uart_port *port, u32 baud)
+{
+ u32 quot;
+
+ quot = (port->uartclk / baud) - 2;
+ return quot;
+}
+
+static void ma35d1serial_set_termios(struct uart_port *port,
+ struct ktermios *termios,
+ const struct ktermios *old)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+ u32 lcr = 0;
+ unsigned long flags;
+ u32 baud, quot;
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ lcr = 0;
+ break;
+ case CS6:
+ lcr |= 1;
+ break;
+ case CS7:
+ lcr |= 2;
+ break;
+ case CS8:
+ default:
+ lcr |= 3;
+ break;
+ }
+
+ if (termios->c_cflag & CSTOPB)
+ lcr |= NSB;
+ if (termios->c_cflag & PARENB)
+ lcr |= PBE;
+ if (!(termios->c_cflag & PARODD))
+ lcr |= EPE;
+ if (termios->c_cflag & CMSPAR)
+ lcr |= SPE;
+
+ baud = uart_get_baud_rate(port, termios, old, port->uartclk / 0xffff,
+ port->uartclk / 11);
+
+ quot = ma35d1serial_get_divisor(port, baud);
+
+ /*
+ * Ok, we're now changing the port state. Do it with
+ * interrupts disabled.
+ */
+ spin_lock_irqsave(&up->port.lock, flags);
+
+ up->port.read_status_mask = RX_OVER_IF;
+ if (termios->c_iflag & INPCK)
+ up->port.read_status_mask |= FEF | PEF;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ up->port.read_status_mask |= BIF;
+
+ /*
+ * Characteres to ignore
+ */
+ up->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= FEF | PEF;
+ if (termios->c_iflag & IGNBRK) {
+ up->port.ignore_status_mask |= BIF;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= RX_OVER_IF;
+ }
+ if (termios->c_cflag & CRTSCTS)
+ up->mcr |= UART_MCR_AFE;
+ else
+ up->mcr &= ~UART_MCR_AFE;
+
+ ma35d1serial_set_mctrl(&up->port, up->port.mctrl);
+ serial_out(up, UART_REG_BAUD, quot | 0x30000000);
+ serial_out(up, UART_REG_LCR, lcr);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static void ma35d1serial_release_port(struct uart_port *port)
+{
+ iounmap(port->membase);
+ port->membase = NULL;
+}
+
+static int ma35d1serial_request_port(struct uart_port *port)
+{
+ return 0;
+}
+
+static void ma35d1serial_config_port(struct uart_port *port, int flags)
+{
+ int ret;
+
+ /*
+ * Find the region that we can probe for. This in turn
+ * tells us whether we can probe for the type of port.
+ */
+ ret = ma35d1serial_request_port(port);
+ if (ret < 0)
+ return;
+ port->type = PORT_MA35D1;
+}
+
+static int ma35d1serial_verify_port(struct uart_port *port,
+ struct serial_struct *ser)
+{
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_MA35D1)
+ return -EINVAL;
+ return 0;
+}
+
+static const char *ma35d1serial_type(struct uart_port *port)
+{
+ return (port->type == PORT_MA35D1) ? "MA35D1" : NULL;
+}
+
+/* Enable or disable the rs485 support */
+static int ma35d1serial_config_rs485(struct uart_port *port,
+ struct ktermios *termios,
+ struct serial_rs485 *rs485conf)
+{
+ struct uart_ma35d1_port *p = to_ma35d1_uart_port(port);
+
+ p->rs485 = *rs485conf;
+
+ if (p->rs485.delay_rts_before_send >= 1000)
+ p->rs485.delay_rts_before_send = 1000;
+
+ serial_out(p, UART_FUN_SEL,
+ (serial_in(p, UART_FUN_SEL) & ~FUN_SEL_MASK));
+
+ if (rs485conf->flags & SER_RS485_ENABLED) {
+ serial_out(p, UART_FUN_SEL,
+ (serial_in(p, UART_FUN_SEL) | FUN_SEL_RS485));
+
+ if (rs485conf->flags & SER_RS485_RTS_ON_SEND)
+ serial_out(p, UART_REG_MCR,
+ (serial_in(p, UART_REG_MCR) & ~0x200));
+ else
+ serial_out(p, UART_REG_MCR,
+ (serial_in(p, UART_REG_MCR) | 0x200));
+
+ /* set auto direction mode */
+ serial_out(p, UART_REG_ALT_CSR,
+ (serial_in(p, UART_REG_ALT_CSR) | (1 << 10)));
+ }
+ return 0;
+}
+
+static int ma35d1serial_ioctl(struct uart_port *port, u32 cmd, unsigned long arg)
+{
+ switch (cmd) {
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static const struct uart_ops ma35d1serial_ops = {
+ .tx_empty = ma35d1serial_tx_empty,
+ .set_mctrl = ma35d1serial_set_mctrl,
+ .get_mctrl = ma35d1serial_get_mctrl,
+ .stop_tx = ma35d1serial_stop_tx,
+ .start_tx = ma35d1serial_start_tx,
+ .stop_rx = ma35d1serial_stop_rx,
+ .break_ctl = ma35d1serial_break_ctl,
+ .startup = ma35d1serial_startup,
+ .shutdown = ma35d1serial_shutdown,
+ .set_termios = ma35d1serial_set_termios,
+ .type = ma35d1serial_type,
+ .release_port = ma35d1serial_release_port,
+ .request_port = ma35d1serial_request_port,
+ .config_port = ma35d1serial_config_port,
+ .verify_port = ma35d1serial_verify_port,
+ .ioctl = ma35d1serial_ioctl,
+};
+
+static const struct of_device_id ma35d1_serial_of_match[] = {
+ { .compatible = "nuvoton,ma35d1-uart" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ma35d1_serial_of_match);
+
+#ifdef CONFIG_SERIAL_NUVOTON_MA35D1_CONSOLE
+
+static void ma35d1serial_console_putchar(struct uart_port *port,
+ unsigned char ch)
+{
+ struct uart_ma35d1_port *up = (struct uart_ma35d1_port *)port;
+
+ do {
+ } while ((serial_in(up, UART_REG_FSR) & TX_FULL));
+ serial_out(up, UART_REG_THR, ch);
+}
+
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ *
+ * The console_lock must be held when we get here.
+ */
+static void ma35d1serial_console_write(struct console *co,
+ const char *s, u32 count)
+{
+ struct uart_ma35d1_port *up = &ma35d1serial_ports[co->index];
+ unsigned long flags;
+ u32 ier;
+
+ local_irq_save(flags);
+
+ /*
+ * First save the IER then disable the interrupts
+ */
+ ier = serial_in(up, UART_REG_IER);
+ serial_out(up, UART_REG_IER, 0);
+
+ uart_console_write(&up->port, s, count, ma35d1serial_console_putchar);
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the IER
+ */
+ do {
+ } while (!(serial_in(up, UART_REG_FSR) & TX_EMPTY));
+ serial_out(up, UART_REG_IER, ier);
+ local_irq_restore(flags);
+}
+
+static int __init ma35d1serial_console_setup(struct console *co,
+ char *options)
+{
+ struct device_node *np = ma35d1serial_uart_nodes[co->index];
+ struct uart_ma35d1_port *p = &ma35d1serial_ports[co->index];
+ u32 val32[4];
+ struct uart_port *port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ /*
+ * Check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ if ((co->index < 0) || (co->index >= UART_NR)) {
+ pr_debug("Console Port%x out of range\n", co->index);
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_array(np, "reg", val32, 4) != 0)
+ return -EINVAL;
+ p->port.iobase = val32[1];
+ p->port.membase = ioremap(p->port.iobase, 0x10000);
+ p->port.ops = &ma35d1serial_ops;
+ p->port.line = 0;
+ p->port.uartclk = 24000000;
+
+ port = &ma35d1serial_ports[co->index].port;
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+static struct console ma35d1serial_console = {
+ .name = "ttyS",
+ .write = ma35d1serial_console_write,
+ .device = uart_console_device,
+ .setup = ma35d1serial_console_setup,
+ .flags = CON_PRINTBUFFER | CON_ENABLED,
+ .index = -1,
+ .data = &ma35d1serial_reg,
+};
+
+static void
+ma35d1serial_console_init_port(void)
+{
+ int i = 0;
+ struct device_node *np;
+
+ for_each_matching_node(np, ma35d1_serial_of_match) {
+ if (ma35d1serial_uart_nodes[i] == NULL) {
+ ma35d1serial_uart_nodes[i] = np;
+ i++;
+ }
+ }
+}
+
+static int __init ma35d1serial_console_init(void)
+{
+ ma35d1serial_console_init_port();
+ register_console(&ma35d1serial_console);
+ return 0;
+}
+console_initcall(ma35d1serial_console_init);
+
+#define MA35D1SERIAL_CONSOLE (&ma35d1serial_console)
+#else
+#define MA35D1SERIAL_CONSOLE NULL
+#endif
+
+static struct uart_driver ma35d1serial_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "serial",
+ .dev_name = "ttyS",
+ .major = TTY_MAJOR,
+ .minor = 64,
+ .cons = MA35D1SERIAL_CONSOLE,
+ .nr = UART_NR,
+};
+
+/**
+ * Suspend one serial port.
+ */
+void ma35d1serial_suspend_port(int line)
+{
+ uart_suspend_port(&ma35d1serial_reg, &ma35d1serial_ports[line].port);
+}
+EXPORT_SYMBOL(ma35d1serial_suspend_port);
+
+/**
+ * Resume one serial port.
+ */
+void ma35d1serial_resume_port(int line)
+{
+ struct uart_ma35d1_port *up = &ma35d1serial_ports[line];
+
+ uart_resume_port(&ma35d1serial_reg, &up->port);
+}
+EXPORT_SYMBOL(ma35d1serial_resume_port);
+
+/*
+ * Register a set of serial devices attached to a platform device.
+ * The list is terminated with a zero flags entry, which means we expect
+ * all entries to have at least UPF_BOOT_AUTOCONF set.
+ */
+static int ma35d1serial_probe(struct platform_device *pdev)
+{
+ struct resource *res_mem;
+ struct uart_ma35d1_port *up;
+ int ret;
+ struct clk *clk;
+ int err;
+
+ if (pdev->dev.of_node) {
+ ret = of_alias_get_id(pdev->dev.of_node, "serial");
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "failed to get alias/pdev id, errno %d\n",
+ ret);
+ return ret;
+ }
+ }
+ up = &ma35d1serial_ports[ret];
+ up->port.line = ret;
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res_mem)
+ return -ENODEV;
+
+ up->port.iobase = res_mem->start;
+ up->port.membase = ioremap(up->port.iobase, 0x10000);
+ up->port.ops = &ma35d1serial_ops;
+
+ spin_lock_init(&up->port.lock);
+
+ clk = of_clk_get(pdev->dev.of_node, 0);
+ if (IS_ERR(clk)) {
+ err = PTR_ERR(clk);
+ dev_err(&pdev->dev, "failed to get core clk: %d\n", err);
+ return -ENOENT;
+ }
+ err = clk_prepare_enable(clk);
+ if (err)
+ return -ENOENT;
+
+ if (up->port.line != 0)
+ up->port.uartclk = clk_get_rate(clk);
+ up->port.irq = platform_get_irq(pdev, 0);
+ up->port.dev = &pdev->dev;
+ up->port.flags = UPF_BOOT_AUTOCONF;
+ up->port.rs485_config = ma35d1serial_config_rs485;
+ ret = uart_add_one_port(&ma35d1serial_reg, &up->port);
+ platform_set_drvdata(pdev, up);
+ return 0;
+}
+
+/*
+ * Remove serial ports registered against a platform device.
+ */
+static int ma35d1serial_remove(struct platform_device *dev)
+{
+ int i;
+ struct uart_port *port = platform_get_drvdata(dev);
+
+ free_irq(port->irq, port);
+ for (i = 0; i < UART_NR; i++) {
+ struct uart_ma35d1_port *up = &ma35d1serial_ports[i];
+
+ if (up->port.dev == &dev->dev)
+ uart_remove_one_port(&ma35d1serial_reg, &up->port);
+ }
+ return 0;
+}
+
+static int ma35d1serial_suspend(struct platform_device *dev,
+ pm_message_t state)
+{
+ int i;
+ struct uart_ma35d1_port *up;
+
+ if (dev->dev.of_node)
+ i = of_alias_get_id(dev->dev.of_node, "serial");
+ if (i < 0) {
+ dev_err(&dev->dev, "failed to get alias/pdev id, errno %d\n",
+ i);
+ return i;
+ }
+ up = &ma35d1serial_ports[i];
+ if (i == 0) {
+ up->console_baud_rate = serial_in(up, UART_REG_BAUD);
+ up->console_line = serial_in(up, UART_REG_LCR);
+ up->console_int = serial_in(up, UART_REG_IER);
+ }
+ return 0;
+}
+
+static int ma35d1serial_resume(struct platform_device *dev)
+{
+ int i;
+ struct uart_ma35d1_port *up;
+
+ if (dev->dev.of_node)
+ i = of_alias_get_id(dev->dev.of_node, "serial");
+ if (i < 0) {
+ dev_err(&dev->dev, "failed to get alias/pdev id, errno %d\n",
+ i);
+ return i;
+ }
+ up = &ma35d1serial_ports[i];
+ if (i == 0) {
+ serial_out(up, UART_REG_BAUD, up->console_baud_rate);
+ serial_out(up, UART_REG_LCR, up->console_line);
+ serial_out(up, UART_REG_IER, up->console_int);
+ }
+ return 0;
+}
+
+static struct platform_driver ma35d1serial_driver = {
+ .probe = ma35d1serial_probe,
+ .remove = ma35d1serial_remove,
+ .suspend = ma35d1serial_suspend,
+ .resume = ma35d1serial_resume,
+ .driver = {
+ .name = "ma35d1-uart",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(ma35d1_serial_of_match),
+ },
+};
+
+static int __init ma35d1serial_init(void)
+{
+ int ret;
+
+ ret = uart_register_driver(&ma35d1serial_reg);
+ if (ret)
+ return ret;
+ ret = platform_driver_register(&ma35d1serial_driver);
+ if (ret)
+ uart_unregister_driver(&ma35d1serial_reg);
+ return ret;
+}
+
+static void __exit ma35d1serial_exit(void)
+{
+ platform_driver_unregister(&ma35d1serial_driver);
+ uart_unregister_driver(&ma35d1serial_reg);
+}
+
+module_init(ma35d1serial_init);
+module_exit(ma35d1serial_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MA35D1 serial driver");
+MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR);
+
diff --git a/drivers/tty/serial/ma35d1_serial.h b/drivers/tty/serial/ma35d1_serial.h
new file mode 100644
index 000000000000..5fd845c31b29
--- /dev/null
+++ b/drivers/tty/serial/ma35d1_serial.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * MA35D1 serial driver header file
+ * Copyright (C) 2023 Nuvoton Technology Corp.
+ */
+#ifndef __MA35D1_SERIAL_H__
+#define __MA35D1_SERIAL_H__
+
+/* UART Receive/Transmit Buffer Register */
+#define UART_REG_RBR 0x00
+#define UART_REG_THR 0x00
+
+/* UART Interrupt Enable Register */
+#define UART_REG_IER 0x04
+#define RDA_IEN 0x00000001 /* RBR Available Interrupt Enable */
+#define THRE_IEN 0x00000002 /* THR Empty Interrupt Enable */
+#define RLS_IEN 0x00000004 /* RX Line Status Interrupt Enable */
+#define RTO_IEN 0x00000010 /* RX Time-out Interrupt Enable */
+#define BUFERR_IEN 0x00000020 /* Buffer Error Interrupt Enable */
+#define TIME_OUT_EN 0x00000800 /* RX Buffer Time-out Counter Enable */
+
+/* UART FIFO Control Register */
+#define UART_REG_FCR 0x08
+#define RFR 0x00000002 /* RX Field Software Reset */
+#define TFR 0x00000004 /* TX Field Software Reset */
+
+/* UART Line Control Register */
+#define UART_REG_LCR 0x0C
+#define NSB 0x00000004 /* Number of “STOP Bit” */
+#define PBE 0x00000008 /* Parity Bit Enable */
+#define EPE 0x00000010 /* Even Parity Enable */
+#define SPE 0x00000020 /* Stick Parity Enable */
+#define BCB 0x00000040 /* Break Control */
+
+/* UART Modem Control Register */
+#define UART_REG_MCR 0x10
+#define RTS 0x00000020 /* nRTS Signal Control */
+#define RTSACTLV 0x00000200 /* nRTS Pin Active Level */
+#define RTSSTS 0x00002000 /* nRTS Pin Status (Read Only) */
+
+/* UART Modem Status Register */
+#define UART_REG_MSR 0x14
+#define CTSDETF 0x00000001 /* Detect nCTS State Change Flag */
+#define CTSSTS 0x00000010 /* nCTS Pin Status (Read Only) */
+#define CTSACTLV 0x00000100 /* nCTS Pin Active Level */
+
+/* UART FIFO Status Register */
+#define UART_REG_FSR 0x18
+#define RX_OVER_IF 0x00000001 /* RX Overflow Error Interrupt Flag */
+#define PEF 0x00000010 /* Parity Error Flag*/
+#define FEF 0x00000020 /* Framing Error Flag */
+#define BIF 0x00000040 /* Break Interrupt Flag */
+#define RX_EMPTY 0x00004000 /* Receiver FIFO Empty (Read Only) */
+#define RX_FULL 0x00008000 /* Receiver FIFO Full (Read Only) */
+#define TX_EMPTY 0x00400000 /* Transmitter FIFO Empty (Read Only) */
+#define TX_FULL 0x00800000 /* Transmitter FIFO Full (Read Only) */
+#define TX_OVER_IF 0x01000000 /* TX Overflow Error Interrupt Flag */
+#define TE_FLAG 0x10000000 /* Transmitter Empty Flag (Read Only) */
+
+/* UART Interrupt Status Register */
+#define UART_REG_ISR 0x1C
+#define RDA_IF 0x00000001 /* RBR Available Interrupt Flag */
+#define THRE_IF 0x00000002 /* THR Empty Interrupt Flag */
+#define RLSIF 0x00000004 /* Receive Line Interrupt Flag */
+#define MODEMIF 0x00000008 /* MODEM Interrupt Flag */
+#define RXTO_IF 0x00000010 /* RX Time-out Interrupt Flag */
+#define BUFEIF 0x00000020 /* Buffer Error Interrupt Flag */
+#define WK_IF 0x00000040 /* UART Wake-up Interrupt Flag */
+#define RDAINT 0x00000100 /* RBR Available Interrupt Indicator */
+#define THRE_INT 0x00000200 /* THR Empty Interrupt Indicator */
+
+/* UART Time-out Register */
+#define UART_REG_TOR 0x20
+
+/* UART Baud Rate Divider Register */
+#define UART_REG_BAUD 0x24
+
+/* UART Alternate Control/Status Register */
+#define UART_REG_ALT_CSR 0x2C
+
+/* UART Function Select Register */
+#define UART_FUN_SEL 0x30
+#define FUN_SEL_UART 0x00000000
+#define FUN_SEL_RS485 0x00000003
+#define FUN_SEL_MASK 0x00000007
+
+/* UART Wake-up Control Register */
+#define UART_REG_WKCTL 0x40
+
+/* UART Wake-up Status Register */
+#define UART_REG_WKSTS 0x44
+
+#endif /* __MA35D1_SERIAL_H__ */
diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
index 281fa286555c..c6d53db17042 100644
--- a/include/uapi/linux/serial_core.h
+++ b/include/uapi/linux/serial_core.h
@@ -279,4 +279,7 @@
/* Sunplus UART */
#define PORT_SUNPLUS 123
+/* Nuvoton MA35D1 UART */
+#define PORT_MA35D1 124
+
#endif /* _UAPILINUX_SERIAL_CORE_H */
--
2.34.1