1 // SPDX-License-Identifier: GPL-2.0+
3  * altera_uart.c -- Altera UART driver
5  * Based on mcf.c -- Freescale ColdFire UART driver
7  * (C) Copyright 2003-2007, Greg Ungerer <gerg@snapgear.com>
54 #define ALTERA_UART_STATUS_DCTS_MSK	0x0400	/* CTS logic-level change */
55 #define ALTERA_UART_STATUS_CTS_MSK	0x0800	/* CTS logic state */
70 #define ALTERA_UART_CONTROL_DCTS_MSK	0x0400	/* Interrupt on CTS change */
75  * Local per-uart structure.
86 	return readl(port->membase + (reg << port->regshift));  in altera_uart_readl()
91 	writel(dat, port->membase + (reg << port->regshift));  in altera_uart_writel()
107 	sigs |= (pp->sigs & TIOCM_RTS);  in altera_uart_get_mctrl()
114 	unsigned short imr = pp->imr;  in altera_uart_update_ctrl_reg()
120 	if (!pp->port.irq)  in altera_uart_update_ctrl_reg()
123 	altera_uart_writel(&pp->port, imr, ALTERA_UART_CONTROL_REG);  in altera_uart_update_ctrl_reg()
130 	pp->sigs = sigs;  in altera_uart_set_mctrl()
132 		pp->imr |= ALTERA_UART_CONTROL_RTS_MSK;  in altera_uart_set_mctrl()
134 		pp->imr &= ~ALTERA_UART_CONTROL_RTS_MSK;  in altera_uart_set_mctrl()
142 	pp->imr |= ALTERA_UART_CONTROL_TRDY_MSK;  in altera_uart_start_tx()
150 	pp->imr &= ~ALTERA_UART_CONTROL_TRDY_MSK;  in altera_uart_stop_tx()
158 	pp->imr &= ~ALTERA_UART_CONTROL_RRDY_MSK;  in altera_uart_stop_rx()
167 	spin_lock_irqsave(&port->lock, flags);  in altera_uart_break_ctl()
168 	if (break_state == -1)  in altera_uart_break_ctl()
169 		pp->imr |= ALTERA_UART_CONTROL_TRBK_MSK;  in altera_uart_break_ctl()
171 		pp->imr &= ~ALTERA_UART_CONTROL_TRBK_MSK;  in altera_uart_break_ctl()
173 	spin_unlock_irqrestore(&port->lock, flags);  in altera_uart_break_ctl()
184 	baudclk = port->uartclk / baud;  in altera_uart_set_termios()
190 	spin_lock_irqsave(&port->lock, flags);  in altera_uart_set_termios()
191 	uart_update_timeout(port, termios->c_cflag, baud);  in altera_uart_set_termios()
193 	spin_unlock_irqrestore(&port->lock, flags);  in altera_uart_set_termios()
196 	 * FIXME: port->read_status_mask and port->ignore_status_mask  in altera_uart_set_termios()
204 	struct uart_port *port = &pp->port;  in altera_uart_rx_chars()
212 		port->icount.rx++;  in altera_uart_rx_chars()
219 				port->icount.brk++;  in altera_uart_rx_chars()
223 				port->icount.parity++;  in altera_uart_rx_chars()
225 				port->icount.overrun++;  in altera_uart_rx_chars()
227 				port->icount.frame++;  in altera_uart_rx_chars()
230 			status &= port->read_status_mask;  in altera_uart_rx_chars()
246 	tty_flip_buffer_push(&port->state->port);  in altera_uart_rx_chars()
251 	struct uart_port *port = &pp->port;  in altera_uart_tx_chars()
252 	struct circ_buf *xmit = &port->state->xmit;  in altera_uart_tx_chars()
254 	if (port->x_char) {  in altera_uart_tx_chars()
255 		/* Send special char - probably flow control */  in altera_uart_tx_chars()
256 		altera_uart_writel(port, port->x_char, ALTERA_UART_TXDATA_REG);  in altera_uart_tx_chars()
257 		port->x_char = 0;  in altera_uart_tx_chars()
258 		port->icount.tx++;  in altera_uart_tx_chars()
264 		if (xmit->head == xmit->tail)  in altera_uart_tx_chars()
266 		altera_uart_writel(port, xmit->buf[xmit->tail],  in altera_uart_tx_chars()
268 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);  in altera_uart_tx_chars()
269 		port->icount.tx++;  in altera_uart_tx_chars()
275 	if (xmit->head == xmit->tail) {  in altera_uart_tx_chars()
276 		pp->imr &= ~ALTERA_UART_CONTROL_TRDY_MSK;  in altera_uart_tx_chars()
287 	isr = altera_uart_readl(port, ALTERA_UART_STATUS_REG) & pp->imr;  in altera_uart_interrupt()
289 	spin_lock(&port->lock);  in altera_uart_interrupt()
294 	spin_unlock(&port->lock);  in altera_uart_interrupt()
302 	struct uart_port *port = &pp->port;  in altera_uart_timer()
305 	mod_timer(&pp->tmr, jiffies + uart_poll_timeout(port));  in altera_uart_timer()
310 	port->type = PORT_ALTERA_UART;  in altera_uart_config_port()
323 	if (!port->irq) {  in altera_uart_startup()
324 		timer_setup(&pp->tmr, altera_uart_timer, 0);  in altera_uart_startup()
325 		mod_timer(&pp->tmr, jiffies + uart_poll_timeout(port));  in altera_uart_startup()
329 		ret = request_irq(port->irq, altera_uart_interrupt, 0,  in altera_uart_startup()
333 			       "interrupt vector=%d\n", port->line, port->irq);  in altera_uart_startup()
338 	spin_lock_irqsave(&port->lock, flags);  in altera_uart_startup()
341 	pp->imr = ALTERA_UART_CONTROL_RRDY_MSK;  in altera_uart_startup()
344 	spin_unlock_irqrestore(&port->lock, flags);  in altera_uart_startup()
354 	spin_lock_irqsave(&port->lock, flags);  in altera_uart_shutdown()
357 	pp->imr = 0;  in altera_uart_shutdown()
360 	spin_unlock_irqrestore(&port->lock, flags);  in altera_uart_shutdown()
362 	if (port->irq)  in altera_uart_shutdown()
363 		free_irq(port->irq, port);  in altera_uart_shutdown()
365 		del_timer_sync(&pp->tmr);  in altera_uart_shutdown()
370 	return (port->type == PORT_ALTERA_UART) ? "Altera UART" : NULL;  in altera_uart_type()
387 	if ((ser->type != PORT_UNKNOWN) && (ser->type != PORT_ALTERA_UART))  in altera_uart_verify_port()
388 		return -EINVAL;  in altera_uart_verify_port()
453 	struct uart_port *port = &(altera_uart_ports + co->index)->port;  in altera_uart_console_write()
466 	if (co->index < 0 || co->index >= CONFIG_SERIAL_ALTERA_UART_MAXPORTS)  in altera_uart_console_setup()
467 		return -EINVAL;  in altera_uart_console_setup()
468 	port = &altera_uart_ports[co->index].port;  in altera_uart_console_setup()
469 	if (!port->membase)  in altera_uart_console_setup()
470 		return -ENODEV;  in altera_uart_console_setup()
486 	.index	= -1,
503 	struct earlycon_device *dev = co->data;  in altera_uart_earlycon_write()
505 	uart_console_write(&dev->port, s, count, altera_uart_console_putc);  in altera_uart_earlycon_write()
511 	struct uart_port *port = &dev->port;  in altera_uart_earlycon_setup()
513 	if (!port->membase)  in altera_uart_earlycon_setup()
514 		return -ENODEV;  in altera_uart_earlycon_setup()
520 	if (dev->baud) {  in altera_uart_earlycon_setup()
521 		unsigned int baudclk = port->uartclk / dev->baud;  in altera_uart_earlycon_setup()
526 	dev->con->write = altera_uart_earlycon_write;  in altera_uart_earlycon_setup()
530 OF_EARLYCON_DECLARE(uart, "altr,uart-1.0", altera_uart_earlycon_setup);
553 	struct altera_uart_platform_uart *platp = dev_get_platdata(&pdev->dev);  in altera_uart_probe()
557 	int i = pdev->id;  in altera_uart_probe()
560 	/* if id is -1 scan for a free id and use that one */  in altera_uart_probe()
561 	if (i == -1) {  in altera_uart_probe()
568 		return -EINVAL;  in altera_uart_probe()
574 		port->mapbase = res_mem->start;  in altera_uart_probe()
576 		port->mapbase = platp->mapbase;  in altera_uart_probe()
578 		return -EINVAL;  in altera_uart_probe()
582 		port->irq = res_irq->start;  in altera_uart_probe()
584 		port->irq = platp->irq;  in altera_uart_probe()
586 	/* Check platform data first so we can override device node data */  in altera_uart_probe()
588 		port->uartclk = platp->uartclk;  in altera_uart_probe()
590 		ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",  in altera_uart_probe()
591 					   &port->uartclk);  in altera_uart_probe()
596 	port->membase = ioremap(port->mapbase, ALTERA_UART_SIZE);  in altera_uart_probe()
597 	if (!port->membase)  in altera_uart_probe()
598 		return -ENOMEM;  in altera_uart_probe()
601 		port->regshift = platp->bus_shift;  in altera_uart_probe()
603 		port->regshift = 0;  in altera_uart_probe()
605 	port->line = i;  in altera_uart_probe()
606 	port->type = PORT_ALTERA_UART;  in altera_uart_probe()
607 	port->iotype = SERIAL_IO_MEM;  in altera_uart_probe()
608 	port->ops = &altera_uart_ops;  in altera_uart_probe()
609 	port->flags = UPF_BOOT_AUTOCONF;  in altera_uart_probe()
610 	port->dev = &pdev->dev;  in altera_uart_probe()
625 		port->mapbase = 0;  in altera_uart_remove()
626 		iounmap(port->membase);  in altera_uart_remove()
634 	{ .compatible = "ALTR,uart-1.0", },
635 	{ .compatible = "altr,uart-1.0", },