12 files changed, 280 insertions, 150 deletions

diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c
index cb7d594d2..5f1140f05 100644
--- a/drivers/tty/serial/8250/8250_bcm7271.c
+++ b/drivers/tty/serial/8250/8250_bcm7271.c
@@ -1121,8 +1121,8 @@ static void brcmuart_remove(struct platform_device *pdev)
 	struct brcmuart_priv *priv = platform_get_drvdata(pdev);
 
 	debugfs_remove_recursive(priv->debugfs_dir);
-	hrtimer_cancel(&priv->hrt);
 	serial8250_unregister_port(priv->line);
+	hrtimer_cancel(&priv->hrt);
 	brcmuart_free_bufs(&pdev->dev, priv);
 	if (priv->dma_enabled)
 		brcmuart_arbitration(priv, 0);
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 3c7775df2..ceecb39fb 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -711,12 +711,6 @@ static int omap_8250_startup(struct uart_port *port)
 	struct uart_8250_dma *dma = &priv->omap8250_dma;
 	int ret;
 
-	if (priv->wakeirq) {
-		ret = dev_pm_set_dedicated_wake_irq(port->dev, priv->wakeirq);
-		if (ret)
-			return ret;
-	}
-
 #ifdef CONFIG_PM
 	up->capabilities |= UART_CAP_RPM;
 #endif
@@ -787,7 +781,6 @@ static void omap_8250_shutdown(struct uart_port *port)
 	}
 
 	disable_irq_nosync(port->irq);
-	dev_pm_clear_wake_irq(port->dev);
 
 	serial8250_release_dma(up);
 	up->dma = NULL;
@@ -1588,6 +1581,12 @@ static int omap8250_probe(struct platform_device *pdev)
 
 	priv->wakeirq = irq_of_parse_and_map(np, 1);
 
+	if (priv->wakeirq) {
+		ret = dev_pm_set_dedicated_wake_irq(&pdev->dev, priv->wakeirq);
+		if (ret)
+			goto err;
+	}
+
 	ret = serial8250_register_8250_port(&up);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "unable to register 8250 port\n");
@@ -1603,6 +1602,7 @@ static int omap8250_probe(struct platform_device *pdev)
 
 	return 0;
 err:
+	dev_pm_clear_wake_irq(&pdev->dev);
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	flush_work(&priv->qos_work);
@@ -1625,6 +1625,7 @@ static void omap8250_remove(struct platform_device *pdev)
 	omap_8250_shutdown(&up->port);
 	serial8250_unregister_port(priv->line);
 	priv->line = -ENODEV;
+	dev_pm_clear_wake_irq(&pdev->dev);
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	flush_work(&priv->qos_work);
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 38fa45e74..1acb73e45 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -3597,7 +3597,7 @@ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
 
 	up->console_line_ended = true;
 	up->console_msr_work_allow = true;
-	init_irq_work(&up->console_msr_work, console_msr_handler);
+	up->console_msr_work = IRQ_WORK_INIT_LAZY(console_msr_handler);
 
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
index 09648d643..64e3f8cf2 100644
--- a/drivers/tty/serial/kgdboc.c
+++ b/drivers/tty/serial/kgdboc.c
@@ -188,6 +188,11 @@ static void cleanup_kgdboc(void)
 
 	kgdboc_unregister_kbd();
 	kgdb_unregister_io_module(&kgdboc_io_ops);
+
+	if (kgdb_tty_driver) {
+		tty_driver_kref_put(kgdb_tty_driver);
+		kgdb_tty_driver = NULL;
+	}
 }
 
 static int configure_kgdboc(void)
@@ -254,6 +259,10 @@ do_register:
 
 noconfig:
 	kgdboc_unregister_kbd();
+	if (kgdb_tty_driver) {
+		tty_driver_kref_put(kgdb_tty_driver);
+		kgdb_tty_driver = NULL;
+	}
 	configured = 0;
 
 	return err;
diff --git a/drivers/tty/serial/ma35d1_serial.c b/drivers/tty/serial/ma35d1_serial.c
index 920fe7ff5..0809655f4 100644
--- a/drivers/tty/serial/ma35d1_serial.c
+++ b/drivers/tty/serial/ma35d1_serial.c
@@ -728,7 +728,7 @@ static int ma35d1serial_probe(struct platform_device *pdev)
 
 	ret = clk_prepare_enable(up->clk);
 	if (ret)
-		goto err_iounmap;
+		goto err_put_clk;
 
 	if (up->port.line != 0)
 		up->port.uartclk = clk_get_rate(up->clk);
@@ -755,6 +755,9 @@ err_free_irq:
 err_clk_disable:
 	clk_disable_unprepare(up->clk);
 
+err_put_clk:
+	clk_put(up->clk);
+
 err_iounmap:
 	iounmap(up->port.membase);
 	return ret;
@@ -770,6 +773,7 @@ static void ma35d1serial_remove(struct platform_device *dev)
 
 	uart_remove_one_port(&ma35d1serial_reg, port);
 	clk_disable_unprepare(up->clk);
+	clk_put(up->clk);
 }
 
 static int ma35d1serial_suspend(struct platform_device *dev, pm_message_t state)
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index a5a5cd68f..f858a6669 100644
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -535,11 +535,11 @@ static void max3100_shutdown(struct uart_port *port)
 	timer_delete_sync(&s->timer);
 
 	if (s->workqueue) {
+		free_irq(port->irq, s);
+		cancel_work_sync(&s->work);
 		destroy_workqueue(s->workqueue);
 		s->workqueue = NULL;
 	}
-	if (port->irq)
-		free_irq(port->irq, s);
 
 	/* set shutdown mode to save power */
 	max3100_sr(s, MAX3100_WC | MAX3100_SHDN, &rx);
@@ -753,6 +753,15 @@ static void max3100_remove(struct spi_device *spi)
 		if (max3100s[i] == s) {
 			dev_dbg(&spi->dev, "%s: removing port %d\n", __func__, i);
 			uart_remove_one_port(&max3100_uart_driver, &max3100s[i]->port);
+
+			s->force_end_work = 1;
+			timer_shutdown_sync(&s->timer);
+			if (s->workqueue) {
+				free_irq(s->port.irq, s);
+				cancel_work_sync(&s->work);
+				destroy_workqueue(s->workqueue);
+				s->workqueue = NULL;
+			}
 			kfree(max3100s[i]);
 			max3100s[i] = NULL;
 			break;
diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c
index b566206f4..472ec39ca 100644
--- a/drivers/tty/serial/mpc52xx_uart.c
+++ b/drivers/tty/serial/mpc52xx_uart.c
@@ -634,6 +634,9 @@ static void __exit mpc512x_psc_fifoc_uninit(void)
 	}
 }
 
+static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM];
+static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM];
+
 /* 512x specific interrupt handler. The caller holds the port lock */
 static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
 {
@@ -654,9 +657,6 @@ static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
 	return IRQ_NONE;
 }
 
-static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM];
-static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM];
-
 /* called from within the .request_port() callback (allocation) */
 static int mpc512x_psc_alloc_clock(struct uart_port *port)
 {
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 3633723ac..a851b8f0e 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -171,7 +171,6 @@ static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport);
 static int qcom_geni_serial_port_setup(struct uart_port *uport);
 static void qcom_geni_serial_start_tx_fifo(struct uart_port *uport);
 static void qcom_geni_serial_resume_tx(struct uart_port *uport);
-static void qcom_geni_serial_poll_rx_fifo_locked(struct uart_port *uport);
 
 static inline struct qcom_geni_serial_port *to_dev_port(struct uart_port *uport)
 {
@@ -467,6 +466,102 @@ static int qcom_geni_serial_poll_init(struct uart_port *uport)
 #endif
 
 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
+static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
+{
+	u32 i;
+	unsigned char buf[sizeof(u32)];
+	struct tty_port *tport;
+	struct qcom_geni_serial_port *port = to_dev_port(uport);
+
+	tport = &uport->state->port;
+	for (i = 0; i < bytes; ) {
+		int c;
+		int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);
+
+		ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
+		i += chunk;
+		if (drop)
+			continue;
+
+		for (c = 0; c < chunk; c++) {
+			int sysrq;
+
+			uport->icount.rx++;
+			if (port->brk && buf[c] == 0) {
+				port->brk = false;
+				if (uart_handle_break(uport))
+					continue;
+			}
+
+			sysrq = uart_prepare_sysrq_char(uport, buf[c]);
+
+			if (!sysrq)
+				tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
+		}
+	}
+	if (!drop)
+		tty_flip_buffer_push(tport);
+}
+#else
+static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
+{
+
+}
+#endif
+
+static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop)
+{
+	u32 status;
+	u32 word_cnt;
+	u32 last_word_byte_cnt;
+	u32 last_word_partial;
+	u32 total_bytes;
+
+	status = readl(uport->membase +	SE_GENI_RX_FIFO_STATUS);
+	word_cnt = status & RX_FIFO_WC_MSK;
+	last_word_partial = status & RX_LAST;
+	last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
+						RX_LAST_BYTE_VALID_SHFT;
+
+	if (!word_cnt)
+		return;
+	total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
+	if (last_word_partial && last_word_byte_cnt)
+		total_bytes += last_word_byte_cnt;
+	else
+		total_bytes += BYTES_PER_FIFO_WORD;
+	handle_rx_console(uport, total_bytes, drop);
+}
+
+#ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
+/* Caller holds the UART port lock. */
+static void qcom_geni_serial_poll_rx_fifo_locked(struct uart_port *uport)
+{
+	struct qcom_geni_serial_port *port = to_dev_port(uport);
+	struct tty_port *tport = &uport->state->port;
+	u32 s_irq_status;
+	bool drop_rx = false;
+
+	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
+	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
+
+	if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
+		uport->icount.overrun++;
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
+	}
+
+	if (s_irq_status & (S_GP_IRQ_0_EN | S_GP_IRQ_1_EN)) {
+		if (s_irq_status & S_GP_IRQ_0_EN)
+			uport->icount.parity++;
+		drop_rx = true;
+	} else if (s_irq_status & (S_GP_IRQ_2_EN | S_GP_IRQ_3_EN)) {
+		uport->icount.brk++;
+		port->brk = true;
+	}
+
+	qcom_geni_serial_handle_rx_fifo(uport, drop_rx);
+}
+
 static void qcom_geni_serial_drain_fifo(struct uart_port *uport)
 {
 	struct qcom_geni_serial_port *port = to_dev_port(uport);
@@ -676,47 +771,6 @@ static void qcom_geni_serial_console_device_unlock(struct console *co,
 #endif
 }
 
-static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
-{
-	u32 i;
-	unsigned char buf[sizeof(u32)];
-	struct tty_port *tport;
-	struct qcom_geni_serial_port *port = to_dev_port(uport);
-
-	tport = &uport->state->port;
-	for (i = 0; i < bytes; ) {
-		int c;
-		int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);
-
-		ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
-		i += chunk;
-		if (drop)
-			continue;
-
-		for (c = 0; c < chunk; c++) {
-			int sysrq;
-
-			uport->icount.rx++;
-			if (port->brk && buf[c] == 0) {
-				port->brk = false;
-				if (uart_handle_break(uport))
-					continue;
-			}
-
-			sysrq = uart_prepare_sysrq_char(uport, buf[c]);
-
-			if (!sysrq)
-				tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
-		}
-	}
-	if (!drop)
-		tty_flip_buffer_push(tport);
-}
-#else
-static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
-{
-
-}
 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
 
 static void handle_rx_uart(struct uart_port *uport, u32 bytes)
@@ -890,58 +944,6 @@ static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport)
 	port->tx_queued = 0;
 }
 
-static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop)
-{
-	u32 status;
-	u32 word_cnt;
-	u32 last_word_byte_cnt;
-	u32 last_word_partial;
-	u32 total_bytes;
-
-	status = readl(uport->membase +	SE_GENI_RX_FIFO_STATUS);
-	word_cnt = status & RX_FIFO_WC_MSK;
-	last_word_partial = status & RX_LAST;
-	last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
-						RX_LAST_BYTE_VALID_SHFT;
-
-	if (!word_cnt)
-		return;
-	total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
-	if (last_word_partial && last_word_byte_cnt)
-		total_bytes += last_word_byte_cnt;
-	else
-		total_bytes += BYTES_PER_FIFO_WORD;
-	handle_rx_console(uport, total_bytes, drop);
-}
-
-/* Caller holds the UART port lock. */
-static void qcom_geni_serial_poll_rx_fifo_locked(struct uart_port *uport)
-{
-	struct qcom_geni_serial_port *port = to_dev_port(uport);
-	struct tty_port *tport = &uport->state->port;
-	u32 s_irq_status;
-	bool drop_rx = false;
-
-	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
-	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
-
-	if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
-		uport->icount.overrun++;
-		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
-	}
-
-	if (s_irq_status & (S_GP_IRQ_0_EN | S_GP_IRQ_1_EN)) {
-		if (s_irq_status & S_GP_IRQ_0_EN)
-			uport->icount.parity++;
-		drop_rx = true;
-	} else if (s_irq_status & (S_GP_IRQ_2_EN | S_GP_IRQ_3_EN)) {
-		uport->icount.brk++;
-		port->brk = true;
-	}
-
-	qcom_geni_serial_handle_rx_fifo(uport, drop_rx);
-}
-
 static void qcom_geni_serial_stop_rx_fifo(struct uart_port *uport)
 {
 	u32 irq_en;
@@ -1482,9 +1484,8 @@ static int geni_serial_set_rate(struct geni_se *se, unsigned long baud)
 	 * Bump up BW vote on CPU and CORE path as driver supports FIFO mode
 	 * only.
 	 */
-	avg_bw_core = (baud > 115200) ? Bps_to_icc(CORE_2X_50_MHZ)
-						: GENI_DEFAULT_BW;
-	port->se.icc_paths[GENI_TO_CORE].avg_bw = avg_bw_core;
+	avg_bw_core = baud > 115200 ? CORE_2X_50_MHZ : CORE_2X_19_2_MHZ;
+	port->se.icc_paths[GENI_TO_CORE].avg_bw = Bps_to_icc(avg_bw_core);
 	port->se.icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(baud);
 	geni_icc_set_bw(&port->se);
 
@@ -1625,16 +1626,37 @@ static int qcom_geni_console_setup(struct console *co, char *options)
 	if (unlikely(!uport->membase))
 		return -ENXIO;
 
+	ret = pm_runtime_resume_and_get(uport->dev);
+	if (ret < 0)
+		return ret;
+
 	if (!port->setup) {
 		ret = qcom_geni_serial_port_setup(uport);
-		if (ret)
+		if (ret) {
+			pm_runtime_put_sync(uport->dev);
 			return ret;
+		}
 	}
 
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 
-	return uart_set_options(uport, co, baud, parity, bits, flow);
+	ret = uart_set_options(uport, co, baud, parity, bits, flow);
+	if (ret)
+		pm_runtime_put_sync(uport->dev);
+
+	return ret;
+}
+
+static int qcom_geni_console_exit(struct console *co)
+{
+	struct qcom_geni_serial_port *port;
+
+	port = get_port_from_line(co->index, true, NULL);
+	if (IS_ERR(port))
+		return PTR_ERR(port);
+
+	return pm_runtime_put_sync(port->uport.dev);
 }
 
 static void qcom_geni_serial_earlycon_write(struct console *con,
@@ -1751,6 +1773,7 @@ static struct console cons_ops = {
 	.device_unlock = qcom_geni_serial_console_device_unlock,
 	.device = uart_console_device,
 	.setup = qcom_geni_console_setup,
+	.exit = qcom_geni_console_exit,
 	.flags = CON_PRINTBUFFER | CON_NBCON,
 	.index = -1,
 	.data = &qcom_geni_console_driver,
@@ -2099,9 +2122,11 @@ static int qcom_geni_serial_resume(struct device *dev)
 	struct uart_port *uport = &port->uport;
 	struct qcom_geni_private_data *private_data = uport->private_data;
 
-	ret = pm_runtime_force_resume(dev);
-	if (ret)
-		return ret;
+	if (console_suspend_enabled || !uart_console(uport)) {
+		ret = pm_runtime_force_resume(dev);
+		if (ret)
+			return ret;
+	}
 
 	ret = uart_resume_port(private_data->drv, uport);
 	if (uart_console(uport)) {
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 7107a0fb1..296079c16 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -216,6 +216,8 @@
 #define SC16IS7XX_TLR_TX_TRIGGER(words)	((((words) / 4) & 0x0f) << 0)
 #define SC16IS7XX_TLR_RX_TRIGGER(words)	((((words) / 4) & 0x0f) << 4)
 
+#define SC16IS7XX_TX_TRIGGER_LEVEL	32
+
 /* IOControl register bits (Only 75x/76x) */
 #define SC16IS7XX_IOCONTROL_LATCH_BIT	BIT(0)   /* Enable input latching */
 #define SC16IS7XX_IOCONTROL_MODEM_A_BIT	BIT(1)   /* Enable GPIO[7:4] as modem A pins */
@@ -647,12 +649,26 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 	tty_flip_buffer_push(&port->state->port);
 }
 
+static unsigned int sc16is7xx_txlvl(struct uart_port *port)
+{
+	unsigned int txlvl;
+
+	txlvl = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
+	if (txlvl > SC16IS7XX_FIFO_SIZE) {
+		dev_err_ratelimited(port->dev,
+				    "chip reports %u free bytes in TX FIFO, but it only has %u\n",
+				    txlvl, SC16IS7XX_FIFO_SIZE);
+		return 0;
+	}
+
+	return txlvl;
+}
+
 static void sc16is7xx_handle_tx(struct uart_port *port)
 {
 	struct tty_port *tport = &port->state->port;
 	unsigned long flags;
 	unsigned int txlen;
-	unsigned char *tail;
 
 	if (unlikely(port->x_char)) {
 		sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char);
@@ -669,17 +685,28 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
 	}
 
 	/* Limit to space available in TX FIFO */
-	txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
-	if (txlen > SC16IS7XX_FIFO_SIZE) {
-		dev_err_ratelimited(port->dev,
-			"chip reports %d free bytes in TX fifo, but it only has %d",
-			txlen, SC16IS7XX_FIFO_SIZE);
-		txlen = 0;
-	}
+	txlen = sc16is7xx_txlvl(port);
+
+	/* Handle circular buffer wrap-around by sending multiple segments */
+	while (txlen > 0 && !kfifo_is_empty(&tport->xmit_fifo)) {
+		unsigned char *tail;
+		unsigned int to_send;
+
+		to_send = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
+		if (!to_send)
+			break;
 
-	txlen = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
-	sc16is7xx_fifo_write(port, tail, txlen);
-	uart_xmit_advance(port, txlen);
+		sc16is7xx_fifo_write(port, tail, to_send);
+		uart_xmit_advance(port, to_send);
+
+		if (kfifo_is_empty(&tport->xmit_fifo))
+			break;
+
+		/* Refill below the trigger to enable the next THRI crossing. */
+		txlen = sc16is7xx_txlvl(port);
+		if (txlen < SC16IS7XX_TX_TRIGGER_LEVEL)
+			break;
+	}
 
 	uart_port_lock_irqsave(port, &flags);
 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
@@ -1130,6 +1157,10 @@ static int sc16is7xx_startup(struct uart_port *port)
 			     SC16IS7XX_TCR_RX_RESUME(24) |
 			     SC16IS7XX_TCR_RX_HALT(48));
 
+	/* Sync hardware and software TX trigger levels */
+	sc16is7xx_port_write(port, SC16IS7XX_TLR_REG,
+			     SC16IS7XX_TLR_TX_TRIGGER(SC16IS7XX_TX_TRIGGER_LEVEL));
+
 	/* Disable TCR/TLR access */
 	sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, SC16IS7XX_MCR_TCRTLR_BIT, 0);
 
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 8004fc00f..b0fc4ae36 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -306,11 +306,19 @@ static void tegra_uart_fifo_reset(struct tegra_uart_port *tup, u8 fcr_bits)
 {
 	unsigned long fcr = tup->fcr_shadow;
 	unsigned int lsr, tmout = 10000;
+	bool clear_tx = !!(fcr_bits & UART_FCR_CLEAR_XMIT);
 
 	if (tup->rts_active)
 		set_rts(tup, false);
 
-	if (tup->cdata->allow_txfifo_reset_fifo_mode) {
+	/*
+	 * Leaving FIFO mode below is a workaround for a Tegra30
+	 * restriction on clearing the Tx FIFO while FIFO mode is
+	 * enabled. It empties both FIFOs, so applying it to an
+	 * Rx-only reset would destroy an in-flight transmission.
+	 * Only take that path when the caller asked for CLEAR_XMIT.
+	 */
+	if (tup->cdata->allow_txfifo_reset_fifo_mode || !clear_tx) {
 		fcr |= fcr_bits & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 		tegra_uart_write(tup, fcr, UART_FCR);
 	} else {
@@ -335,9 +343,15 @@ static void tegra_uart_fifo_reset(struct tegra_uart_port *tup, u8 fcr_bits)
 	 */
 	tegra_uart_wait_cycle_time(tup, 32);
 
+	/*
+	 * Only wait for the transmitter to drain when the Tx FIFO was
+	 * part of the reset. For an Rx-only reset it is left intact,
+	 * and waiting for TEMT here would spin for a full frame time.
+	 */
 	do {
 		lsr = tegra_uart_read(tup, UART_LSR);
-		if ((lsr & UART_LSR_TEMT) && !(lsr & UART_LSR_DR))
+		if ((!clear_tx || (lsr & UART_LSR_TEMT)) &&
+		    !(lsr & UART_LSR_DR))
 			break;
 		udelay(1);
 	} while (--tmout);
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 95774b0f1..6332ed545 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -896,7 +896,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
 	upf_t old_flags, new_flags;
 	int retval;
 
-	if (!uport)
+	if (!uport || tty_io_error(tty))
 		return -EIO;
 
 	new_port = new_info->port;
@@ -1119,7 +1119,7 @@ static int uart_break_ctl(struct tty_struct *tty, int break_state)
 	guard(mutex)(&port->mutex);
 
 	uport = uart_port_check(state);
-	if (!uport)
+	if (!uport || tty_io_error(tty))
 		return -EIO;
 
 	if (uport->type != PORT_UNKNOWN && uport->ops->break_ctl)
@@ -1144,7 +1144,7 @@ static int uart_do_autoconfig(struct tty_struct *tty, struct uart_state *state)
 	 */
 	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &port->mutex) {
 		uport = uart_port_check(state);
-		if (!uport)
+		if (!uport || tty_io_error(tty))
 			return -EIO;
 
 		if (tty_port_users(port) != 1)
@@ -1199,7 +1199,7 @@ static void uart_enable_ms(struct uart_port *uport)
  * FIXME: This wants extracting into a common all driver implementation
  * of TIOCMWAIT using tty_port.
  */
-static int uart_wait_modem_status(struct uart_state *state, unsigned long arg)
+static int uart_wait_modem_status(struct tty_struct *tty, struct uart_state *state, unsigned long arg)
 {
 	struct uart_port *uport;
 	struct tty_port *port = &state->port;
@@ -1213,18 +1213,29 @@ static int uart_wait_modem_status(struct uart_state *state, unsigned long arg)
 	uport = uart_port_ref(state);
 	if (!uport)
 		return -EIO;
-	scoped_guard(uart_port_lock_irq, uport) {
-		memcpy(&cprev, &uport->icount, sizeof(struct uart_icount));
-		uart_enable_ms(uport);
+
+	mutex_lock(&port->mutex);
+	if (tty_io_error(tty)) {
+		mutex_unlock(&port->mutex);
+		ret = -EIO;
+		goto out_deref;
 	}
 
+	uart_port_lock_irq(uport);
+	memcpy(&cprev, &uport->icount, sizeof(struct uart_icount));
+	uart_enable_ms(uport);
+	uart_port_unlock_irq(uport);
+
+	mutex_unlock(&port->mutex);
+
 	add_wait_queue(&port->delta_msr_wait, &wait);
 	for (;;) {
-		scoped_guard(uart_port_lock_irq, uport)
-			memcpy(&cnow, &uport->icount, sizeof(struct uart_icount));
-
 		set_current_state(TASK_INTERRUPTIBLE);
 
+		uart_port_lock_irq(uport);
+		memcpy(&cnow, &uport->icount, sizeof(struct uart_icount));
+		uart_port_unlock_irq(uport);
+
 		if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
 		    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
 		    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
@@ -1233,6 +1244,11 @@ static int uart_wait_modem_status(struct uart_state *state, unsigned long arg)
 			break;
 		}
 
+		if (tty_io_error(tty)) {
+			ret = -EIO;
+			break;
+		}
+
 		schedule();
 
 		/* see if a signal did it */
@@ -1245,6 +1261,7 @@ static int uart_wait_modem_status(struct uart_state *state, unsigned long arg)
 	}
 	__set_current_state(TASK_RUNNING);
 	remove_wait_queue(&port->delta_msr_wait, &wait);
+out_deref:
 	uart_port_deref(uport);
 
 	return ret;
@@ -1567,7 +1584,7 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
 
 	/* This should only be used when the hardware is present. */
 	if (cmd == TIOCMIWAIT)
-		return uart_wait_modem_status(state, arg);
+		return uart_wait_modem_status(tty, state, arg);
 
 	/* rs485_config requires more locking than others */
 	if (cmd == TIOCSRS485)
@@ -1623,14 +1640,13 @@ static void uart_set_ldisc(struct tty_struct *tty)
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *uport;
-	struct tty_port *port = &state->port;
-
-	if (!tty_port_initialized(port))
-		return;
 
 	guard(mutex)(&state->port.mutex);
 	uport = uart_port_check(state);
-	if (uport && uport->ops->set_ldisc)
+	if (!uport || tty_io_error(tty))
+		return;
+
+	if (uport->ops->set_ldisc)
 		uport->ops->set_ldisc(uport, &tty->termios);
 }
 
@@ -1646,7 +1662,7 @@ static void uart_set_termios(struct tty_struct *tty,
 	guard(mutex)(&state->port.mutex);
 
 	uport = uart_port_check(state);
-	if (!uport)
+	if (!uport || tty_io_error(tty))
 		return;
 
 	/*
@@ -1798,7 +1814,14 @@ static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
 	 * 'timeout' / 'expire' give us the maximum amount of time
 	 * we wait.
 	 */
-	while (!port->ops->tx_empty(port)) {
+	for (;;) {
+		mutex_lock(&state->port.mutex);
+		if (tty_io_error(tty) || port->ops->tx_empty(port)) {
+			mutex_unlock(&state->port.mutex);
+			break;
+		}
+		mutex_unlock(&state->port.mutex);
+
 		msleep_interruptible(jiffies_to_msecs(char_time));
 		if (signal_pending(current))
 			break;
@@ -3358,6 +3381,7 @@ int serial_core_register_port(struct uart_driver *drv, struct uart_port *port)
 
 err_unregister_port_dev:
 	serial_base_port_device_remove(port->port_dev);
+	port->port_dev = NULL;
 
 err_unregister_ctrl_dev:
 	serial_base_ctrl_device_remove(new_ctrl_dev);
@@ -3372,12 +3396,24 @@ err_unregister_ctrl_dev:
 void serial_core_unregister_port(struct uart_driver *drv, struct uart_port *port)
 {
 	struct device *phys_dev = port->dev;
-	struct serial_port_device *port_dev = port->port_dev;
-	struct serial_ctrl_device *ctrl_dev = serial_core_get_ctrl_dev(port_dev);
+	struct serial_port_device *port_dev;
+	struct serial_ctrl_device *ctrl_dev;
 	int ctrl_id = port->ctrl_id;
 
 	guard(mutex)(&port_mutex);
 
+	/*
+	 * A NULL port device means there is no registered port device to
+	 * remove: serial_core_remove_one_port() clears port_dev on
+	 * teardown, and it is never set if registration failed before
+	 * serial_core_port_device_add().
+	 */
+	port_dev = port->port_dev;
+	if (!port_dev)
+		return;
+
+	ctrl_dev = serial_core_get_ctrl_dev(port_dev);
+
 	port->flags |= UPF_DEAD;
 
 	serial_core_remove_one_port(drv, port);
diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c
index 78a1c1eea..fc6fdc751 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -656,6 +656,7 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 	ret = clk_prepare_enable(vt8500_port->clk);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to enable clock\n");
+		clk_put(vt8500_port->clk);
 		return ret;
 	}