1 files changed, 72 insertions, 60 deletions

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 66901d93089a..72ae08d6204f 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -19,7 +19,6 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
 #include <linux/of_irq.h>
 #include <linux/delay.h>
 #include <linux/pm_runtime.h>
@@ -28,7 +27,6 @@
 #include <linux/pm_wakeirq.h>
 #include <linux/dma-mapping.h>
 #include <linux/sys_soc.h>
-#include <linux/pm_domain.h>
 
 #include "8250.h"
 
@@ -116,11 +114,9 @@
 /* RX FIFO occupancy indicator */
 #define UART_OMAP_RX_LVL		0x19
 
-/*
- * Copy of the genpd flags for the console.
- * Only used if console suspend is disabled
- */
-static unsigned int genpd_flags_console;
+/* Timeout low and High */
+#define UART_OMAP_TO_L                 0x26
+#define UART_OMAP_TO_H                 0x27
 
 struct omap8250_priv {
 	void __iomem *membase;
@@ -141,7 +137,6 @@ struct omap8250_priv {
 	atomic_t active;
 	bool is_suspending;
 	int wakeirq;
-	int wakeups_enabled;
 	u32 latency;
 	u32 calc_latency;
 	struct pm_qos_request pm_qos_request;
@@ -370,7 +365,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
 
 	if (up->port.rs485.flags & SER_RS485_ENABLED &&
 	    up->port.rs485_config == serial8250_em485_config)
-		serial8250_em485_stop_tx(up);
+		serial8250_em485_stop_tx(up, true);
 }
 
 /*
@@ -417,7 +412,13 @@ static void omap_8250_set_termios(struct uart_port *port,
 	 */
 	uart_update_timeout(port, termios->c_cflag, baud);
 
-	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+	/*
+	 * Specify which conditions may be considered for error
+	 * handling and the ignoring of characters. The actual
+	 * ignoring of characters only occurs if the bit is set
+	 * in @ignore_status_mask as well.
+	 */
+	up->port.read_status_mask = UART_LSR_OE | UART_LSR_DR;
 	if (termios->c_iflag & INPCK)
 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 	if (termios->c_iflag & (IGNBRK | PARMRK))
@@ -664,13 +665,25 @@ static irqreturn_t omap8250_irq(int irq, void *dev_id)
 
 	/*
 	 * On K3 SoCs, it is observed that RX TIMEOUT is signalled after
-	 * FIFO has been drained, in which case a dummy read of RX FIFO
-	 * is required to clear RX TIMEOUT condition.
+	 * FIFO has been drained or erroneously.
+	 * So apply solution of Errata i2310 as mentioned in
+	 * https://www.ti.com/lit/pdf/sprz536
 	 */
 	if (priv->habit & UART_RX_TIMEOUT_QUIRK &&
 	    (iir & UART_IIR_RX_TIMEOUT) == UART_IIR_RX_TIMEOUT &&
 	    serial_port_in(port, UART_OMAP_RX_LVL) == 0) {
-		serial_port_in(port, UART_RX);
+		unsigned char efr2, timeout_h, timeout_l;
+
+		efr2 = serial_in(up, UART_OMAP_EFR2);
+		timeout_h = serial_in(up, UART_OMAP_TO_H);
+		timeout_l = serial_in(up, UART_OMAP_TO_L);
+		serial_out(up, UART_OMAP_TO_H, 0xFF);
+		serial_out(up, UART_OMAP_TO_L, 0xFF);
+		serial_out(up, UART_OMAP_EFR2, UART_OMAP_EFR2_TIMEOUT_BEHAVE);
+		serial_in(up, UART_IIR);
+		serial_out(up, UART_OMAP_EFR2, efr2);
+		serial_out(up, UART_OMAP_TO_H, timeout_h);
+		serial_out(up, UART_OMAP_TO_L, timeout_l);
 	}
 
 	/* Stop processing interrupts on input overrun */
@@ -679,7 +692,7 @@ static irqreturn_t omap8250_irq(int irq, void *dev_id)
 
 		/* Synchronize UART_IER access against the console. */
 		uart_port_lock(port);
-		up->ier = port->serial_in(port, UART_IER);
+		up->ier = serial_port_in(port, UART_IER);
 		if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
 			port->ops->stop_rx(port);
 		} else {
@@ -769,12 +782,12 @@ static void omap_8250_shutdown(struct uart_port *port)
 	struct uart_8250_port *up = up_to_u8250p(port);
 	struct omap8250_priv *priv = port->private_data;
 
+	pm_runtime_get_sync(port->dev);
+
 	flush_work(&priv->qos_work);
 	if (up->dma)
 		omap_8250_rx_dma_flush(up);
 
-	pm_runtime_get_sync(port->dev);
-
 	serial_out(up, UART_OMAP_WER, 0);
 	if (priv->habit & UART_HAS_EFR2)
 		serial_out(up, UART_OMAP_EFR2, 0x0);
@@ -831,7 +844,6 @@ static void omap_8250_unthrottle(struct uart_port *port)
 	if (up->dma)
 		up->dma->rx_dma(up);
 	up->ier |= UART_IER_RLSI | UART_IER_RDI;
-	port->read_status_mask |= UART_LSR_DR;
 	serial_out(up, UART_IER, up->ier);
 	uart_port_unlock_irqrestore(port, flags);
 
@@ -1094,7 +1106,7 @@ static void omap_8250_dma_tx_complete(void *param)
 {
 	struct uart_8250_port	*p = param;
 	struct uart_8250_dma	*dma = p->dma;
-	struct circ_buf		*xmit = &p->port.state->xmit;
+	struct tty_port		*tport = &p->port.state->port;
 	unsigned long		flags;
 	bool			en_thri = false;
 	struct omap8250_priv	*priv = p->port.private_data;
@@ -1113,10 +1125,10 @@ static void omap_8250_dma_tx_complete(void *param)
 		omap8250_restore_regs(p);
 	}
 
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
 		uart_write_wakeup(&p->port);
 
-	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) {
+	if (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(&p->port)) {
 		int ret;
 
 		ret = omap_8250_tx_dma(p);
@@ -1138,14 +1150,15 @@ static int omap_8250_tx_dma(struct uart_8250_port *p)
 {
 	struct uart_8250_dma		*dma = p->dma;
 	struct omap8250_priv		*priv = p->port.private_data;
-	struct circ_buf			*xmit = &p->port.state->xmit;
+	struct tty_port			*tport = &p->port.state->port;
 	struct dma_async_tx_descriptor	*desc;
-	unsigned int	skip_byte = 0;
+	struct scatterlist sg;
+	int skip_byte = -1;
 	int ret;
 
 	if (dma->tx_running)
 		return 0;
-	if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) {
+	if (uart_tx_stopped(&p->port) || kfifo_is_empty(&tport->xmit_fifo)) {
 
 		/*
 		 * Even if no data, we need to return an error for the two cases
@@ -1160,8 +1173,8 @@ static int omap_8250_tx_dma(struct uart_8250_port *p)
 		return 0;
 	}
 
-	dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 	if (priv->habit & OMAP_DMA_TX_KICK) {
+		unsigned char c;
 		u8 tx_lvl;
 
 		/*
@@ -1184,22 +1197,32 @@ static int omap_8250_tx_dma(struct uart_8250_port *p)
 			ret = -EBUSY;
 			goto err;
 		}
-		if (dma->tx_size < 4) {
+		if (kfifo_len(&tport->xmit_fifo) < 4) {
 			ret = -EINVAL;
 			goto err;
 		}
-		skip_byte = 1;
+		if (!uart_fifo_out(&p->port, &c, 1)) {
+			ret = -EINVAL;
+			goto err;
+		}
+		skip_byte = c;
+	}
+
+	sg_init_table(&sg, 1);
+	ret = kfifo_dma_out_prepare_mapped(&tport->xmit_fifo, &sg, 1, UART_XMIT_SIZE, dma->tx_addr);
+	if (ret != 1) {
+		ret = -EINVAL;
+		goto err;
 	}
 
-	desc = dmaengine_prep_slave_single(dma->txchan,
-			dma->tx_addr + xmit->tail + skip_byte,
-			dma->tx_size - skip_byte, DMA_MEM_TO_DEV,
+	desc = dmaengine_prep_slave_sg(dma->txchan, &sg, 1, DMA_MEM_TO_DEV,
 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!desc) {
 		ret = -EBUSY;
 		goto err;
 	}
 
+	dma->tx_size = sg_dma_len(&sg);
 	dma->tx_running = 1;
 
 	desc->callback = omap_8250_dma_tx_complete;
@@ -1215,11 +1238,13 @@ static int omap_8250_tx_dma(struct uart_8250_port *p)
 		dma->tx_err = 0;
 
 	serial8250_clear_THRI(p);
-	if (skip_byte)
-		serial_out(p, UART_TX, xmit->buf[xmit->tail]);
-	return 0;
+	ret = 0;
+	goto out_skip;
 err:
 	dma->tx_err = 1;
+out_skip:
+	if (skip_byte >= 0)
+		serial_out(p, UART_TX, skip_byte);
 	return ret;
 }
 
@@ -1279,7 +1304,7 @@ static void am654_8250_handle_rx_dma(struct uart_8250_port *up, u8 iir,
 
 /*
  * This is mostly serial8250_handle_irq(). We have a slightly different DMA
- * hoook for RX/TX and need different logic for them in the ISR. Therefore we
+ * hook for RX/TX and need different logic for them in the ISR. Therefore we
  * use the default routine in the non-DMA case and this one for with DMA.
  */
 static int omap_8250_dma_handle_irq(struct uart_port *port)
@@ -1308,12 +1333,12 @@ static int omap_8250_dma_handle_irq(struct uart_port *port)
 	serial8250_modem_status(up);
 	if (status & UART_LSR_THRE && up->dma->tx_err) {
 		if (uart_tx_stopped(&up->port) ||
-		    uart_circ_empty(&up->port.state->xmit)) {
+		    kfifo_is_empty(&up->port.state->port.xmit_fifo)) {
 			up->dma->tx_err = 0;
 			serial8250_tx_chars(up);
 		} else  {
 			/*
-			 * try again due to an earlier failer which
+			 * try again due to an earlier failure which
 			 * might have been resolved by now.
 			 */
 			if (omap_8250_tx_dma(up))
@@ -1497,7 +1522,10 @@ static int omap8250_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, priv);
 
-	device_init_wakeup(&pdev->dev, true);
+	device_set_wakeup_capable(&pdev->dev, true);
+	if (of_property_read_bool(np, "wakeup-source"))
+		device_set_wakeup_enable(&pdev->dev, true);
+
 	pm_runtime_enable(&pdev->dev);
 	pm_runtime_use_autosuspend(&pdev->dev);
 
@@ -1555,7 +1583,7 @@ static int omap8250_probe(struct platform_device *pdev)
 	ret = devm_request_irq(&pdev->dev, up.port.irq, omap8250_irq, 0,
 			       dev_name(&pdev->dev), priv);
 	if (ret < 0)
-		return ret;
+		goto err;
 
 	priv->wakeirq = irq_of_parse_and_map(np, 1);
 
@@ -1596,7 +1624,7 @@ static void omap8250_remove(struct platform_device *pdev)
 	flush_work(&priv->qos_work);
 	pm_runtime_disable(&pdev->dev);
 	cpu_latency_qos_remove_request(&priv->pm_qos_request);
-	device_init_wakeup(&pdev->dev, false);
+	device_set_wakeup_capable(&pdev->dev, false);
 }
 
 static int omap8250_prepare(struct device *dev)
@@ -1622,7 +1650,6 @@ static int omap8250_suspend(struct device *dev)
 {
 	struct omap8250_priv *priv = dev_get_drvdata(dev);
 	struct uart_8250_port *up = serial8250_get_port(priv->line);
-	struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
 	int err = 0;
 
 	serial8250_suspend_port(priv->line);
@@ -1633,19 +1660,8 @@ static int omap8250_suspend(struct device *dev)
 	if (!device_may_wakeup(dev))
 		priv->wer = 0;
 	serial_out(up, UART_OMAP_WER, priv->wer);
-	if (uart_console(&up->port)) {
-		if (console_suspend_enabled)
-			err = pm_runtime_force_suspend(dev);
-		else {
-			/*
-			 * The pd shall not be powered-off (no console suspend).
-			 * Make copy of genpd flags before to set it always on.
-			 * The original value is restored during the resume.
-			 */
-			genpd_flags_console = genpd->flags;
-			genpd->flags |= GENPD_FLAG_ALWAYS_ON;
-		}
-	}
+	if (uart_console(&up->port) && console_suspend_enabled)
+		err = pm_runtime_force_suspend(dev);
 	flush_work(&priv->qos_work);
 
 	return err;
@@ -1655,16 +1671,12 @@ static int omap8250_resume(struct device *dev)
 {
 	struct omap8250_priv *priv = dev_get_drvdata(dev);
 	struct uart_8250_port *up = serial8250_get_port(priv->line);
-	struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
 	int err;
 
 	if (uart_console(&up->port) && console_suspend_enabled) {
-		if (console_suspend_enabled) {
-			err = pm_runtime_force_resume(dev);
-			if (err)
-				return err;
-		} else
-			genpd->flags = genpd_flags_console;
+		err = pm_runtime_force_resume(dev);
+		if (err)
+			return err;
 	}
 
 	serial8250_resume_port(priv->line);
@@ -1855,7 +1867,7 @@ static struct platform_driver omap8250_platform_driver = {
 		.of_match_table = omap8250_dt_ids,
 	},
 	.probe			= omap8250_probe,
-	.remove_new		= omap8250_remove,
+	.remove			= omap8250_remove,
 };
 module_platform_driver(omap8250_platform_driver);