Merge tag 'tty-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small serial driver fixes, and a larger number of GSM
  line discipline fixes for 5.18-rc5.

  These include:

   - lots of tiny n_gsm fixes for issues to resolve a number of reported
     problems. Seems that people are starting to actually use this code
     again.

   - 8250 driver fixes for some devices

   - imx serial driver fix

   - amba-pl011 driver fix

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

* tag 'tty-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (27 commits)
  tty: n_gsm: fix sometimes uninitialized warning in gsm_dlci_modem_output()
  serial: 8250: Correct the clock for EndRun PTP/1588 PCIe device
  serial: 8250: Also set sticky MCR bits in console restoration
  tty: n_gsm: fix software flow control handling
  tty: n_gsm: fix invalid use of MSC in advanced option
  tty: n_gsm: fix broken virtual tty handling
  Revert "serial: sc16is7xx: Clear RS485 bits in the shutdown"
  tty: n_gsm: fix missing update of modem controls after DLCI open
  serial: 8250: Fix runtime PM for start_tx() for empty buffer
  serial: imx: fix overrun interrupts in DMA mode
  serial: amba-pl011: do not time out prematurely when draining tx fifo
  tty: n_gsm: fix incorrect UA handling
  tty: n_gsm: fix reset fifo race condition
  tty: n_gsm: fix missing tty wakeup in convergence layer type 2
  tty: n_gsm: fix wrong signal octets encoding in MSC
  tty: n_gsm: fix wrong command frame length field encoding
  tty: n_gsm: fix wrong command retry handling
  tty: n_gsm: fix missing explicit ldisc flush
  tty: n_gsm: fix wrong DLCI release order
  tty: n_gsm: fix insufficient txframe size
  ...

drivers/tty/serial/8250/8250_pci.c

@@ -2667,7 +2667,7 @@ enum pci_board_num_t {
 	pbn_panacom2,
 	pbn_panacom4,
 	pbn_plx_romulus,
-	pbn_endrun_2_4000000,
+	pbn_endrun_2_3906250,
 	pbn_oxsemi,
 	pbn_oxsemi_1_3906250,
 	pbn_oxsemi_2_3906250,
@@ -3195,10 +3195,10 @@ static struct pciserial_board pci_boards[] = {
 	* signal now many ports are available
 	* 2 port 952 Uart support
 	*/
-	[pbn_endrun_2_4000000] = {
+	[pbn_endrun_2_3906250] = {
 		.flags		= FL_BASE0,
 		.num_ports	= 2,
-		.base_baud	= 4000000,
+		.base_baud	= 3906250,
 		.uart_offset	= 0x200,
 		.first_offset	= 0x1000,
 	},
@@ -4115,7 +4115,7 @@ static const struct pci_device_id serial_pci_tbl[] = {
 	*/
 	{	PCI_VENDOR_ID_ENDRUN, PCI_DEVICE_ID_ENDRUN_1588,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-		pbn_endrun_2_4000000 },
+		pbn_endrun_2_3906250 },
 	/*
 	 * Quatech cards. These actually have configurable clocks but for
 	 * now we just use the default.

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

@@ -1675,11 +1675,11 @@ static void serial8250_start_tx(struct uart_port *port)
 	struct uart_8250_port *up = up_to_u8250p(port);
 	struct uart_8250_em485 *em485 = up->em485;
 
-	serial8250_rpm_get_tx(up);
-
 	if (!port->x_char && uart_circ_empty(&port->state->xmit))
 		return;
 
+	serial8250_rpm_get_tx(up);
+
 	if (em485 &&
 	    em485->active_timer == &em485->start_tx_timer)
 		return;
@@ -3329,7 +3329,7 @@ static void serial8250_console_restore(struct uart_8250_port *up)
 
 	serial8250_set_divisor(port, baud, quot, frac);
 	serial_port_out(port, UART_LCR, up->lcr);
-	serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
+	serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);
 }
 
 /*

drivers/tty/serial/amba-pl011.c

@@ -1255,13 +1255,18 @@ static inline bool pl011_dma_rx_running(struct uart_amba_port *uap)
 
 static void pl011_rs485_tx_stop(struct uart_amba_port *uap)
 {
+	/*
+	 * To be on the safe side only time out after twice as many iterations
+	 * as fifo size.
+	 */
+	const int MAX_TX_DRAIN_ITERS = uap->port.fifosize * 2;
 	struct uart_port *port = &uap->port;
 	int i = 0;
 	u32 cr;
 
 	/* Wait until hardware tx queue is empty */
 	while (!pl011_tx_empty(port)) {
-		if (i == port->fifosize) {
+		if (i > MAX_TX_DRAIN_ITERS) {
 			dev_warn(port->dev,
 				 "timeout while draining hardware tx queue\n");
 			break;
@@ -2052,7 +2057,7 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
 	 * with the given baud rate. We use this as the poll interval when we
 	 * wait for the tx queue to empty.
 	 */
-	uap->rs485_tx_drain_interval = (bits * 1000 * 1000) / baud;
+	uap->rs485_tx_drain_interval = DIV_ROUND_UP(bits * 1000 * 1000, baud);
 
 	pl011_setup_status_masks(port, termios);
 

drivers/tty/serial/imx.c

@@ -1448,7 +1448,7 @@ static int imx_uart_startup(struct uart_port *port)
 	imx_uart_writel(sport, ucr1, UCR1);
 
 	ucr4 = imx_uart_readl(sport, UCR4) & ~(UCR4_OREN | UCR4_INVR);
-	if (!sport->dma_is_enabled)
+	if (!dma_is_inited)
 		ucr4 |= UCR4_OREN;
 	if (sport->inverted_rx)
 		ucr4 |= UCR4_INVR;

drivers/tty/serial/sc16is7xx.c

@@ -1238,12 +1238,10 @@ static void sc16is7xx_shutdown(struct uart_port *port)
 
 	/* Disable all interrupts */
 	sc16is7xx_port_write(port, SC16IS7XX_IER_REG, 0);
-	/* Disable TX/RX, clear auto RS485 and RTS invert */
+	/* Disable TX/RX */
 	sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
 			      SC16IS7XX_EFCR_RXDISABLE_BIT |
-			      SC16IS7XX_EFCR_TXDISABLE_BIT |
-			      SC16IS7XX_EFCR_AUTO_RS485_BIT |
-			      SC16IS7XX_EFCR_RTS_INVERT_BIT,
+			      SC16IS7XX_EFCR_TXDISABLE_BIT,
 			      SC16IS7XX_EFCR_RXDISABLE_BIT |
 			      SC16IS7XX_EFCR_TXDISABLE_BIT);