1 // SPDX-License-Identifier: GPL-2.0
50 #define TXDE	(1 << 0)	/* Tx Data empty */
51 #define RXDF	(1 << 1)	/* Rx Data full */
52 #define TXFAE	(1 << 2)	/* Tx FIFO almost empty */
53 #define TXFE	(1 << 3)	/* Tx FIFO empty */
54 #define RXFAF	(1 << 4)	/* Rx FIFO almost full */
55 #define RXFF	(1 << 5)	/* Rx FIFO full */
56 #define TXUDR	(1 << 6)	/* Tx underrun */
57 #define RXOVER	(1 << 7)	/* Rx overrun */
58 #define PER	(1 << 8)	/* Parity error */
59 #define FER	(1 << 9)	/* Frame error */
60 #define TCTS	(1 << 10)	/* Toggle of CTS */
61 #define RXTOUT	(1 << 11)	/* Rx timeout */
62 #define BKDONE	(1 << 12)	/* Break signal done */
63 #define ERR	(1 << 13)	/* AHB error response */
72 #define VT8500_TXEN	(1 << 0)	/* Enable transmit logic */
73 #define VT8500_RXEN	(1 << 1)	/* Enable receive logic */
74 #define VT8500_CS8	(1 << 2)	/* 8-bit data length (vs. 7-bit) */
75 #define VT8500_CSTOPB	(1 << 3)	/* 2 stop bits (vs. 1) */
76 #define VT8500_PARENB	(1 << 4)	/* Enable parity */
77 #define VT8500_PARODD	(1 << 5)	/* Odd parity (vs. even) */
78 #define VT8500_RTS	(1 << 6)	/* Ready to send */
79 #define VT8500_LOOPBK	(1 << 7)	/* Enable internal loopback */
80 #define VT8500_DMA	(1 << 8)	/* Enable DMA mode (needs FIFO) */
81 #define VT8500_BREAK	(1 << 9)	/* Initiate break signal */
82 #define VT8500_PSLVERR	(1 << 10)	/* APB error upon empty RX FIFO read */
83 #define VT8500_SWRTSCTS	(1 << 11)	/* Software-controlled RTS/CTS */
86  * Capability flags (driver-internal)
89 #define VT8500_HAS_SWRTSCTS_SWITCH	(1 << 1)
106  * have been allocated as we can't use pdev->id in
111 static inline void vt8500_write(struct uart_port *port, unsigned int val,  in vt8500_write()  argument
114 	writel(val, port->membase + off);  in vt8500_write()
117 static inline unsigned int vt8500_read(struct uart_port *port, unsigned int off)  in vt8500_read()  argument
119 	return readl(port->membase + off);  in vt8500_read()
122 static void vt8500_stop_tx(struct uart_port *port)  in vt8500_stop_tx()  argument
124 	struct vt8500_port *vt8500_port = container_of(port,  in vt8500_stop_tx()
128 	vt8500_port->ier &= ~TX_FIFO_INTS;  in vt8500_stop_tx()
129 	vt8500_write(port, vt8500_port->ier, VT8500_URIER);  in vt8500_stop_tx()
132 static void vt8500_stop_rx(struct uart_port *port)  in vt8500_stop_rx()  argument
134 	struct vt8500_port *vt8500_port = container_of(port,  in vt8500_stop_rx()
138 	vt8500_port->ier &= ~RX_FIFO_INTS;  in vt8500_stop_rx()
139 	vt8500_write(port, vt8500_port->ier, VT8500_URIER);  in vt8500_stop_rx()
142 static void vt8500_enable_ms(struct uart_port *port)  in vt8500_enable_ms()  argument
144 	struct vt8500_port *vt8500_port = container_of(port,  in vt8500_enable_ms()
148 	vt8500_port->ier |= TCTS;  in vt8500_enable_ms()
149 	vt8500_write(port, vt8500_port->ier, VT8500_URIER);  in vt8500_enable_ms()
152 static void handle_rx(struct uart_port *port)  in handle_rx()  argument
154 	struct tty_port *tport = &port->state->port;  in handle_rx()
159 	if ((vt8500_read(port, VT8500_URISR) & RXOVER)) {  in handle_rx()
160 		port->icount.overrun++;  in handle_rx()
165 	while (vt8500_read(port, VT8500_URFIDX) & 0x1f00) {  in handle_rx()
169 		c = readw(port->membase + VT8500_RXFIFO) & 0x3ff;  in handle_rx()
172 		c &= ~port->read_status_mask;  in handle_rx()
175 			port->icount.frame++;  in handle_rx()
178 			port->icount.parity++;  in handle_rx()
181 		port->icount.rx++;  in handle_rx()
183 		if (!uart_handle_sysrq_char(port, c))  in handle_rx()
190 static unsigned int vt8500_tx_empty(struct uart_port *port)  in vt8500_tx_empty()  argument
192 	unsigned int idx = vt8500_read(port, VT8500_URFIDX) & 0x1f;  in vt8500_tx_empty()
197 static void handle_tx(struct uart_port *port)  in handle_tx()  argument
201 	uart_port_tx(port, ch,  in handle_tx()
202 		vt8500_tx_empty(port),  in handle_tx()
203 		writeb(ch, port->membase + VT8500_TXFIFO));  in handle_tx()
206 static void vt8500_start_tx(struct uart_port *port)  in vt8500_start_tx()  argument
208 	struct vt8500_port *vt8500_port = container_of(port,  in vt8500_start_tx()
212 	vt8500_port->ier &= ~TX_FIFO_INTS;  in vt8500_start_tx()
213 	vt8500_write(port, vt8500_port->ier, VT8500_URIER);  in vt8500_start_tx()
214 	handle_tx(port);  in vt8500_start_tx()
215 	vt8500_port->ier |= TX_FIFO_INTS;  in vt8500_start_tx()
216 	vt8500_write(port, vt8500_port->ier, VT8500_URIER);  in vt8500_start_tx()
219 static void handle_delta_cts(struct uart_port *port)  in handle_delta_cts()  argument
221 	port->icount.cts++;  in handle_delta_cts()
222 	wake_up_interruptible(&port->state->port.delta_msr_wait);  in handle_delta_cts()
227 	struct uart_port *port = dev_id;  in vt8500_irq()  local
230 	uart_port_lock(port);  in vt8500_irq()
231 	isr = vt8500_read(port, VT8500_URISR);  in vt8500_irq()
234 	vt8500_write(port, isr, VT8500_URISR);  in vt8500_irq()
237 		handle_rx(port);  in vt8500_irq()
239 		handle_tx(port);  in vt8500_irq()
241 		handle_delta_cts(port);  in vt8500_irq()
243 	uart_port_unlock(port);  in vt8500_irq()
248 static unsigned int vt8500_get_mctrl(struct uart_port *port)  in vt8500_get_mctrl()  argument
252 	usr = vt8500_read(port, VT8500_URUSR);  in vt8500_get_mctrl()
253 	if (usr & (1 << 4))  in vt8500_get_mctrl()
259 static void vt8500_set_mctrl(struct uart_port *port, unsigned int mctrl)  in vt8500_set_mctrl()  argument
261 	unsigned int lcr = vt8500_read(port, VT8500_URLCR);  in vt8500_set_mctrl()
268 	vt8500_write(port, lcr, VT8500_URLCR);  in vt8500_set_mctrl()
271 static void vt8500_break_ctl(struct uart_port *port, int break_ctl)  in vt8500_break_ctl()  argument
274 		vt8500_write(port,  in vt8500_break_ctl()
275 			     vt8500_read(port, VT8500_URLCR) | VT8500_BREAK,  in vt8500_break_ctl()
279 static int vt8500_set_baud_rate(struct uart_port *port, unsigned int baud)  in vt8500_set_baud_rate()  argument
282 			container_of(port, struct vt8500_port, uart);  in vt8500_set_baud_rate()
286 	div = ((vt8500_port->clk_predivisor - 1) & 0xf) << 16;  in vt8500_set_baud_rate()
287 	div |= (uart_get_divisor(port, baud) - 1) & 0x3ff;  in vt8500_set_baud_rate()
290 	baud = port->uartclk / 16 / ((div & 0x3ff) + 1);  in vt8500_set_baud_rate()
292 	while ((vt8500_read(port, VT8500_URUSR) & (1 << 5)) && --loops)  in vt8500_set_baud_rate()
295 	vt8500_write(port, div, VT8500_URDIV);  in vt8500_set_baud_rate()
298 	vt8500_write(port, mult_frac(baud, 4096, 1000000), VT8500_URBKR);  in vt8500_set_baud_rate()
303 static int vt8500_startup(struct uart_port *port)  in vt8500_startup()  argument
306 			container_of(port, struct vt8500_port, uart);  in vt8500_startup()
309 	snprintf(vt8500_port->name, sizeof(vt8500_port->name),  in vt8500_startup()
310 		 "vt8500_serial%d", port->line);  in vt8500_startup()
312 	ret = request_irq(port->irq, vt8500_irq, IRQF_TRIGGER_HIGH,  in vt8500_startup()
313 			  vt8500_port->name, port);  in vt8500_startup()
317 	vt8500_write(port, 0x03, VT8500_URLCR);	/* enable TX & RX */  in vt8500_startup()
322 static void vt8500_shutdown(struct uart_port *port)  in vt8500_shutdown()  argument
325 			container_of(port, struct vt8500_port, uart);  in vt8500_shutdown()
327 	vt8500_port->ier = 0;  in vt8500_shutdown()
330 	vt8500_write(&vt8500_port->uart, 0, VT8500_URIER);  in vt8500_shutdown()
331 	vt8500_write(&vt8500_port->uart, 0x880, VT8500_URFCR);  in vt8500_shutdown()
332 	free_irq(port->irq, port);  in vt8500_shutdown()
335 static void vt8500_set_termios(struct uart_port *port,  in vt8500_set_termios()  argument
340 			container_of(port, struct vt8500_port, uart);  in vt8500_set_termios()
345 	uart_port_lock_irqsave(port, &flags);  in vt8500_set_termios()
348 	baud = uart_get_baud_rate(port, termios, old, 900, 921600);  in vt8500_set_termios()
349 	baud = vt8500_set_baud_rate(port, baud);  in vt8500_set_termios()
354 	lcr = vt8500_read(&vt8500_port->uart, VT8500_URLCR);  in vt8500_set_termios()
356 	if (termios->c_cflag & PARENB) {  in vt8500_set_termios()
358 		termios->c_cflag &= ~CMSPAR;  in vt8500_set_termios()
359 		if (termios->c_cflag & PARODD)  in vt8500_set_termios()
365 	switch (termios->c_cflag & CSIZE) {  in vt8500_set_termios()
371 		termios->c_cflag &= ~CSIZE;  in vt8500_set_termios()
372 		termios->c_cflag |= CS8;  in vt8500_set_termios()
378 	if (termios->c_cflag & CSTOPB)  in vt8500_set_termios()
382 	if (vt8500_port->vt8500_uart_flags & VT8500_HAS_SWRTSCTS_SWITCH)  in vt8500_set_termios()
386 	vt8500_write(&vt8500_port->uart, lcr, VT8500_URLCR);  in vt8500_set_termios()
389 	port->read_status_mask = 0;  in vt8500_set_termios()
390 	if (termios->c_iflag & IGNPAR)  in vt8500_set_termios()
391 		port->read_status_mask = FER | PER;  in vt8500_set_termios()
393 	uart_update_timeout(port, termios->c_cflag, baud);  in vt8500_set_termios()
396 	vt8500_write(&vt8500_port->uart, 0x88c, VT8500_URFCR);  in vt8500_set_termios()
397 	while ((vt8500_read(&vt8500_port->uart, VT8500_URFCR) & 0xc)  in vt8500_set_termios()
398 							&& --loops)  in vt8500_set_termios()
401 	/* Every possible FIFO-related interrupt */  in vt8500_set_termios()
402 	vt8500_port->ier = RX_FIFO_INTS | TX_FIFO_INTS;  in vt8500_set_termios()
407 	if (UART_ENABLE_MS(&vt8500_port->uart, termios->c_cflag))  in vt8500_set_termios()
408 		vt8500_port->ier |= TCTS;  in vt8500_set_termios()
410 	vt8500_write(&vt8500_port->uart, 0x881, VT8500_URFCR);  in vt8500_set_termios()
411 	vt8500_write(&vt8500_port->uart, vt8500_port->ier, VT8500_URIER);  in vt8500_set_termios()
413 	uart_port_unlock_irqrestore(port, flags);  in vt8500_set_termios()
416 static const char *vt8500_type(struct uart_port *port)  in vt8500_type()  argument
419 			container_of(port, struct vt8500_port, uart);  in vt8500_type()
420 	return vt8500_port->name;  in vt8500_type()
423 static void vt8500_release_port(struct uart_port *port)  in vt8500_release_port()  argument
427 static int vt8500_request_port(struct uart_port *port)  in vt8500_request_port()  argument
432 static void vt8500_config_port(struct uart_port *port, int flags)  in vt8500_config_port()  argument
434 	port->type = PORT_VT8500;  in vt8500_config_port()
437 static int vt8500_verify_port(struct uart_port *port,  in vt8500_verify_port()  argument
440 	if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_VT8500))  in vt8500_verify_port()
441 		return -EINVAL;  in vt8500_verify_port()
442 	if (unlikely(port->irq != ser->irq))  in vt8500_verify_port()
443 		return -EINVAL;  in vt8500_verify_port()
452 static void wait_for_xmitr(struct uart_port *port)  in wait_for_xmitr()  argument
458 		status = vt8500_read(port, VT8500_URFIDX);  in wait_for_xmitr()
460 		if (--tmout == 0)  in wait_for_xmitr()
462 		udelay(1);  in wait_for_xmitr()
466 static void vt8500_console_putchar(struct uart_port *port, unsigned char c)  in vt8500_console_putchar()  argument
468 	wait_for_xmitr(port);  in vt8500_console_putchar()
469 	writeb(c, port->membase + VT8500_TXFIFO);  in vt8500_console_putchar()
475 	struct vt8500_port *vt8500_port = vt8500_uart_ports[co->index];  in vt8500_console_write()
478 	BUG_ON(co->index < 0 || co->index >= vt8500_uart_driver.nr);  in vt8500_console_write()
480 	ier = vt8500_read(&vt8500_port->uart, VT8500_URIER);  in vt8500_console_write()
481 	vt8500_write(&vt8500_port->uart, VT8500_URIER, 0);  in vt8500_console_write()
483 	uart_console_write(&vt8500_port->uart, s, count,  in vt8500_console_write()
490 	wait_for_xmitr(&vt8500_port->uart);  in vt8500_console_write()
491 	vt8500_write(&vt8500_port->uart, VT8500_URIER, ier);  in vt8500_console_write()
502 	if (unlikely(co->index >= vt8500_uart_driver.nr || co->index < 0))  in vt8500_console_setup()
503 		return -ENXIO;  in vt8500_console_setup()
505 	vt8500_port = vt8500_uart_ports[co->index];  in vt8500_console_setup()
508 		return -ENODEV;  in vt8500_console_setup()
513 	return uart_set_options(&vt8500_port->uart,  in vt8500_console_setup()
523 	.index = -1,
534 static int vt8500_get_poll_char(struct uart_port *port)  in vt8500_get_poll_char()  argument
536 	unsigned int status = vt8500_read(port, VT8500_URFIDX);  in vt8500_get_poll_char()
541 	return vt8500_read(port, VT8500_RXFIFO) & 0xff;  in vt8500_get_poll_char()
544 static void vt8500_put_poll_char(struct uart_port *port, unsigned char c)  in vt8500_put_poll_char()  argument
549 		status = vt8500_read(port, VT8500_URFIDX);  in vt8500_put_poll_char()
551 		if (--tmout == 0)  in vt8500_put_poll_char()
553 		udelay(1);  in vt8500_put_poll_char()
556 	vt8500_write(port, c, VT8500_TXFIFO);  in vt8500_put_poll_char()
595 	{ .compatible = "via,vt8500-uart", .data = &vt8500_flags},
596 	{ .compatible = "wm,wm8880-uart", .data = &wm8880_flags},
604 	struct device_node *np = pdev->dev.of_node;  in vt8500_serial_probe()
607 	int port;  in vt8500_serial_probe()  local
610 	flags = of_device_get_match_data(&pdev->dev);  in vt8500_serial_probe()
612 		return -EINVAL;  in vt8500_serial_probe()
619 		port = of_alias_get_id(np, "serial");  in vt8500_serial_probe()
620 		if (port >= VT8500_MAX_PORTS)  in vt8500_serial_probe()
621 			port = -1;  in vt8500_serial_probe()
623 		port = -1;  in vt8500_serial_probe()
626 	if (port < 0) {  in vt8500_serial_probe()
627 		/* calculate the port id */  in vt8500_serial_probe()
628 		port = find_first_zero_bit(vt8500_ports_in_use,  in vt8500_serial_probe()
632 	if (port >= VT8500_MAX_PORTS)  in vt8500_serial_probe()
633 		return -ENODEV;  in vt8500_serial_probe()
635 	/* reserve the port id */  in vt8500_serial_probe()
636 	if (test_and_set_bit(port, vt8500_ports_in_use)) {  in vt8500_serial_probe()
637 		/* port already in use - shouldn't really happen */  in vt8500_serial_probe()
638 		return -EBUSY;  in vt8500_serial_probe()
641 	vt8500_port = devm_kzalloc(&pdev->dev, sizeof(struct vt8500_port),  in vt8500_serial_probe()
644 		return -ENOMEM;  in vt8500_serial_probe()
646 	vt8500_port->uart.membase = devm_platform_get_and_ioremap_resource(pdev, 0, &mmres);  in vt8500_serial_probe()
647 	if (IS_ERR(vt8500_port->uart.membase))  in vt8500_serial_probe()
648 		return PTR_ERR(vt8500_port->uart.membase);  in vt8500_serial_probe()
650 	vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0);  in vt8500_serial_probe()
651 	if (IS_ERR(vt8500_port->clk)) {  in vt8500_serial_probe()
652 		dev_err(&pdev->dev, "failed to get clock\n");  in vt8500_serial_probe()
653 		return  -EINVAL;  in vt8500_serial_probe()
656 	ret = clk_prepare_enable(vt8500_port->clk);  in vt8500_serial_probe()
658 		dev_err(&pdev->dev, "failed to enable clock\n");  in vt8500_serial_probe()
662 	vt8500_port->vt8500_uart_flags = *flags;  in vt8500_serial_probe()
663 	vt8500_port->clk_predivisor = DIV_ROUND_CLOSEST(  in vt8500_serial_probe()
664 					clk_get_rate(vt8500_port->clk),  in vt8500_serial_probe()
667 	vt8500_port->uart.type = PORT_VT8500;  in vt8500_serial_probe()
668 	vt8500_port->uart.iotype = UPIO_MEM;  in vt8500_serial_probe()
669 	vt8500_port->uart.mapbase = mmres->start;  in vt8500_serial_probe()
670 	vt8500_port->uart.irq = irq;  in vt8500_serial_probe()
671 	vt8500_port->uart.fifosize = 16;  in vt8500_serial_probe()
672 	vt8500_port->uart.ops = &vt8500_uart_pops;  in vt8500_serial_probe()
673 	vt8500_port->uart.line = port;  in vt8500_serial_probe()
674 	vt8500_port->uart.dev = &pdev->dev;  in vt8500_serial_probe()
675 	vt8500_port->uart.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;  in vt8500_serial_probe()
676 	vt8500_port->uart.has_sysrq = IS_ENABLED(CONFIG_SERIAL_VT8500_CONSOLE);  in vt8500_serial_probe()
678 	/* Serial core uses the magic "16" everywhere - adjust for it */  in vt8500_serial_probe()
679 	vt8500_port->uart.uartclk = 16 * clk_get_rate(vt8500_port->clk) /  in vt8500_serial_probe()
680 					vt8500_port->clk_predivisor /  in vt8500_serial_probe()
683 	snprintf(vt8500_port->name, sizeof(vt8500_port->name),  in vt8500_serial_probe()
684 		 "VT8500 UART%d", pdev->id);  in vt8500_serial_probe()
686 	vt8500_uart_ports[port] = vt8500_port;  in vt8500_serial_probe()
688 	uart_add_one_port(&vt8500_uart_driver, &vt8500_port->uart);  in vt8500_serial_probe()