1 files changed, 99 insertions, 26 deletions

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 7bd080720929..7c9457962a3d 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -31,6 +31,7 @@
 #include <linux/ioport.h>
 #include <linux/ktime.h>
 #include <linux/major.h>
+#include <linux/minmax.h>
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/of.h>
@@ -587,14 +588,28 @@ static void sci_start_tx(struct uart_port *port)
 
 	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
 	    dma_submit_error(s->cookie_tx)) {
+		if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
+			/* Switch irq from SCIF to DMA */
+			disable_irq(s->irqs[SCIx_TXI_IRQ]);
+
 		s->cookie_tx = 0;
 		schedule_work(&s->work_tx);
 	}
 #endif
 
-	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+	if (!s->chan_tx || s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE ||
+	    port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
 		ctrl = serial_port_in(port, SCSCR);
+
+		/*
+		 * For SCI, TE (transmit enable) must be set after setting TIE
+		 * (transmit interrupt enable) or in the same instruction to start
+		 * the transmit process.
+		 */
+		if (port->type == PORT_SCI)
+			ctrl |= SCSCR_TE;
+
 		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
 	}
 }
@@ -832,6 +847,11 @@ static void sci_transmit_chars(struct uart_port *port)
 		} else if (!uart_circ_empty(xmit) && !stopped) {
 			c = xmit->buf[xmit->tail];
 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		} else if (port->type == PORT_SCI && uart_circ_empty(xmit)) {
+			ctrl = serial_port_in(port, SCSCR);
+			ctrl &= ~SCSCR_TE;
+			serial_port_out(port, SCSCR, ctrl);
+			return;
 		} else {
 			break;
 		}
@@ -845,9 +865,16 @@ static void sci_transmit_chars(struct uart_port *port)
 
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
-	if (uart_circ_empty(xmit))
-		sci_stop_tx(port);
+	if (uart_circ_empty(xmit)) {
+		if (port->type == PORT_SCI) {
+			ctrl = serial_port_in(port, SCSCR);
+			ctrl &= ~SCSCR_TIE;
+			ctrl |= SCSCR_TEIE;
+			serial_port_out(port, SCSCR, ctrl);
+		}
 
+		sci_stop_tx(port);
+	}
 }
 
 static void sci_receive_chars(struct uart_port *port)
@@ -1191,9 +1218,15 @@ static void sci_dma_tx_complete(void *arg)
 		schedule_work(&s->work_tx);
 	} else {
 		s->cookie_tx = -EINVAL;
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
+		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 			u16 ctrl = serial_port_in(port, SCSCR);
 			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
+			if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+				/* Switch irq from DMA to SCIF */
+				dmaengine_pause(s->chan_tx_saved);
+				enable_irq(s->irqs[SCIx_TXI_IRQ]);
+			}
 		}
 	}
 
@@ -1265,9 +1298,13 @@ static void sci_dma_rx_reenable_irq(struct sci_port *s)
 
 	/* Direct new serial port interrupts back to CPU */
 	scr = serial_port_in(port, SCSCR);
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
-		scr &= ~SCSCR_RDRQE;
+	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
+	    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 		enable_irq(s->irqs[SCIx_RXI_IRQ]);
+		if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
+			scif_set_rtrg(port, s->rx_trigger);
+		else
+			scr &= ~SCSCR_RDRQE;
 	}
 	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
 }
@@ -1504,7 +1541,8 @@ static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
 			tty_flip_buffer_push(&port->state->port);
 	}
 
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
+	    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
 		sci_dma_rx_submit(s, true);
 
 	sci_dma_rx_reenable_irq(s);
@@ -1530,15 +1568,12 @@ static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
 
 	memset(&cfg, 0, sizeof(cfg));
 	cfg.direction = dir;
-	if (dir == DMA_MEM_TO_DEV) {
-		cfg.dst_addr = port->mapbase +
-			(sci_getreg(port, SCxTDR)->offset << port->regshift);
-		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
-	} else {
-		cfg.src_addr = port->mapbase +
-			(sci_getreg(port, SCxRDR)->offset << port->regshift);
-		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
-	}
+	cfg.dst_addr = port->mapbase +
+		(sci_getreg(port, SCxTDR)->offset << port->regshift);
+	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+	cfg.src_addr = port->mapbase +
+		(sci_getreg(port, SCxRDR)->offset << port->regshift);
+	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 
 	ret = dmaengine_slave_config(chan, &cfg);
 	if (ret) {
@@ -1573,7 +1608,7 @@ static void sci_request_dma(struct uart_port *port)
 	 * Don't request a dma channel if no channel was specified
 	 * in the device tree.
 	 */
-	if (!of_find_property(port->dev->of_node, "dmas", NULL))
+	if (!of_property_present(port->dev->of_node, "dmas"))
 		return;
 
 	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
@@ -1631,7 +1666,8 @@ static void sci_request_dma(struct uart_port *port)
 
 		s->chan_rx_saved = s->chan_rx = chan;
 
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
+		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
 			sci_dma_rx_submit(s, false);
 	}
 }
@@ -1684,9 +1720,15 @@ static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
 		u16 ssr = serial_port_in(port, SCxSR);
 
 		/* Disable future Rx interrupts */
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
-			disable_irq_nosync(irq);
-			scr |= SCSCR_RDRQE;
+		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
+		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+			disable_irq_nosync(s->irqs[SCIx_RXI_IRQ]);
+			if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+				scif_set_rtrg(port, 1);
+				scr |= SCSCR_RIE;
+			} else {
+				scr |= SCSCR_RDRQE;
+			}
 		} else {
 			if (sci_dma_rx_submit(s, false) < 0)
 				goto handle_pio;
@@ -1736,6 +1778,24 @@ static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t sci_tx_end_interrupt(int irq, void *ptr)
+{
+	struct uart_port *port = ptr;
+	unsigned long flags;
+	unsigned short ctrl;
+
+	if (port->type != PORT_SCI)
+		return sci_tx_interrupt(irq, ptr);
+
+	spin_lock_irqsave(&port->lock, flags);
+	ctrl = serial_port_in(port, SCSCR);
+	ctrl &= ~(SCSCR_TE | SCSCR_TEIE);
+	serial_port_out(port, SCSCR, ctrl);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
 {
 	struct uart_port *port = ptr;
@@ -1872,7 +1932,7 @@ static const struct sci_irq_desc {
 
 	[SCIx_TEI_IRQ] = {
 		.desc = "tx end",
-		.handler = sci_tx_interrupt,
+		.handler = sci_tx_end_interrupt,
 	},
 
 	/*
@@ -2579,8 +2639,14 @@ done:
 		sci_set_mctrl(port, port->mctrl);
 	}
 
-	scr_val |= SCSCR_RE | SCSCR_TE |
-		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
+	/*
+	 * For SCI, TE (transmit enable) must be set after setting TIE
+	 * (transmit interrupt enable) or in the same instruction to
+	 * start the transmitting process. So skip setting TE here for SCI.
+	 */
+	if (port->type != PORT_SCI)
+		scr_val |= SCSCR_TE;
+	scr_val |= SCSCR_RE | (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
 	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
 	if ((srr + 1 == 5) &&
 	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
@@ -2864,6 +2930,13 @@ static int sci_init_single(struct platform_device *dev,
 			sci_port->irqs[i] = platform_get_irq(dev, i);
 	}
 
+	/*
+	 * The fourth interrupt on SCI port is transmit end interrupt, so
+	 * shuffle the interrupts.
+	 */
+	if (p->type == PORT_SCI)
+		swap(sci_port->irqs[SCIx_BRI_IRQ], sci_port->irqs[SCIx_TEI_IRQ]);
+
 	/* The SCI generates several interrupts. They can be muxed together or
 	 * connected to different interrupt lines. In the muxed case only one
 	 * interrupt resource is specified as there is only one interrupt ID.
@@ -2929,7 +3002,7 @@ static int sci_init_single(struct platform_device *dev,
 	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
 	port->fifosize		= sci_port->params->fifosize;
 
-	if (port->type == PORT_SCI) {
+	if (port->type == PORT_SCI && !dev->dev.of_node) {
 		if (sci_port->reg_size >= 0x20)
 			port->regshift = 2;
 		else
@@ -3141,7 +3214,7 @@ static int sci_remove(struct platform_device *dev)
 #define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
 #define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
 
-static const struct of_device_id of_sci_match[] = {
+static const struct of_device_id of_sci_match[] __maybe_unused = {
 	/* SoC-specific types */
 	{
 		.compatible = "renesas,scif-r7s72100",