TTY/Serial driver fixes for 6.3-rc6

Here are some small tty and serial driver fixes for some reported
 problems:
   - fsl_uart driver bugfixes
   - sh-sci serial driver bugfixes
   - renesas serial driver DT binding bugfixes
   - 8250 DMA bugfix
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver fixes from Greg KH:
 "Here are some small tty and serial driver fixes for some reported
  problems:

   - fsl_uart driver bugfixes

   - sh-sci serial driver bugfixes

   - renesas serial driver DT binding bugfixes

   - 8250 DMA bugfix

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'tty-6.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: serial: sh-sci: Fix Rx on RZ/G2L SCI
  tty: serial: fsl_lpuart: fix crash in lpuart_uport_is_active
  tty: serial: fsl_lpuart: avoid checking for transfer complete when UARTCTRL_SBK is asserted in lpuart32_tx_empty
  serial: 8250: Prevent starting up DMA Rx on THRI interrupt
  dt-bindings: serial: renesas,scif: Fix 4th IRQ for 4-IRQ SCIFs
  tty: serial: sh-sci: Fix transmit end interrupt handler

Documentation/devicetree/bindings/serial/renesas,scif.yaml

@@ -92,7 +92,7 @@ properties:
           - description: Error interrupt
           - description: Receive buffer full interrupt
           - description: Transmit buffer empty interrupt
-          - description: Transmit End interrupt
+          - description: Break interrupt
       - items:
           - description: Error interrupt
           - description: Receive buffer full interrupt
@@ -107,7 +107,7 @@ properties:
           - const: eri
           - const: rxi
           - const: txi
-          - const: tei
+          - const: bri
       - items:
           - const: eri
           - const: rxi

drivers/tty/serial/8250/8250_port.c

@@ -1903,6 +1903,17 @@ EXPORT_SYMBOL_GPL(serial8250_modem_status);
 static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
 {
 	switch (iir & 0x3f) {
+	case UART_IIR_THRI:
+		/*
+		 * Postpone DMA or not decision to IIR_RDI or IIR_RX_TIMEOUT
+		 * because it's impossible to do an informed decision about
+		 * that with IIR_THRI.
+		 *
+		 * This also fixes one known DMA Rx corruption issue where
+		 * DR is asserted but DMA Rx only gets a corrupted zero byte
+		 * (too early DR?).
+		 */
+		return false;
 	case UART_IIR_RDI:
 		if (!up->dma->rx_running)
 			break;

drivers/tty/serial/fsl_lpuart.c

@@ -858,11 +858,17 @@ static unsigned int lpuart32_tx_empty(struct uart_port *port)
 			struct lpuart_port, port);
 	unsigned long stat = lpuart32_read(port, UARTSTAT);
 	unsigned long sfifo = lpuart32_read(port, UARTFIFO);
+	unsigned long ctrl = lpuart32_read(port, UARTCTRL);
 
 	if (sport->dma_tx_in_progress)
 		return 0;
 
-	if (stat & UARTSTAT_TC && sfifo & UARTFIFO_TXEMPT)
+	/*
+	 * LPUART Transmission Complete Flag may never be set while queuing a break
+	 * character, so avoid checking for transmission complete when UARTCTRL_SBK
+	 * is asserted.
+	 */
+	if ((stat & UARTSTAT_TC && sfifo & UARTFIFO_TXEMPT) || ctrl & UARTCTRL_SBK)
 		return TIOCSER_TEMT;
 
 	return 0;
@@ -2942,7 +2948,7 @@ static bool lpuart_uport_is_active(struct lpuart_port *sport)
 	tty = tty_port_tty_get(port);
 	if (tty) {
 		tty_dev = tty->dev;
-		may_wake = device_may_wakeup(tty_dev);
+		may_wake = tty_dev && device_may_wakeup(tty_dev);
 		tty_kref_put(tty);
 	}
 

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>
@@ -2864,6 +2865,13 @@ 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 +2937,7 @@ 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