Merge tag 'v5.4.69' into 5.4-2.1.x-imx

This is the 5.4.69 stable release

Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com>

6 files changed, 57 insertions, 12 deletions

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 836e736ae188..f2c6d9d3bb28 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -790,7 +790,10 @@ static void __dma_rx_do_complete(struct uart_8250_port *p)
 	dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
 
 	count = dma->rx_size - state.residue;
-
+	if (count < dma->rx_size)
+		dmaengine_terminate_async(dma->rxchan);
+	if (!count)
+		goto unlock;
 	ret = tty_insert_flip_string(tty_port, dma->rx_buf, count);
 
 	p->port.icount.rx += ret;
@@ -852,7 +855,6 @@ static void omap_8250_rx_dma_flush(struct uart_8250_port *p)
 	spin_unlock_irqrestore(&priv->rx_dma_lock, flags);
 
 	__dma_rx_do_complete(p);
-	dmaengine_terminate_all(dma->rxchan);
 }
 
 static int omap_8250_rx_dma(struct uart_8250_port *p)
@@ -1234,6 +1236,7 @@ static int omap8250_probe(struct platform_device *pdev)
 	spin_lock_init(&priv->rx_dma_lock);
 
 	device_init_wakeup(&pdev->dev, true);
+	pm_runtime_enable(&pdev->dev);
 	pm_runtime_use_autosuspend(&pdev->dev);
 
 	/*
@@ -1247,7 +1250,6 @@ static int omap8250_probe(struct platform_device *pdev)
 		pm_runtime_set_autosuspend_delay(&pdev->dev, -1);
 
 	pm_runtime_irq_safe(&pdev->dev);
-	pm_runtime_enable(&pdev->dev);
 
 	pm_runtime_get_sync(&pdev->dev);
 
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 90f09ed6e5ad..5b673077639b 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -1816,6 +1816,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
 	unsigned char status;
 	unsigned long flags;
 	struct uart_8250_port *up = up_to_u8250p(port);
+	bool skip_rx = false;
 
 	if (iir & UART_IIR_NO_INT)
 		return 0;
@@ -1824,7 +1825,20 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
 
 	status = serial_port_in(port, UART_LSR);
 
-	if (status & (UART_LSR_DR | UART_LSR_BI)) {
+	/*
+	 * If port is stopped and there are no error conditions in the
+	 * FIFO, then don't drain the FIFO, as this may lead to TTY buffer
+	 * overflow. Not servicing, RX FIFO would trigger auto HW flow
+	 * control when FIFO occupancy reaches preset threshold, thus
+	 * halting RX. This only works when auto HW flow control is
+	 * available.
+	 */
+	if (!(status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS)) &&
+	    (port->status & (UPSTAT_AUTOCTS | UPSTAT_AUTORTS)) &&
+	    !(port->read_status_mask & UART_LSR_DR))
+		skip_rx = true;
+
+	if (status & (UART_LSR_DR | UART_LSR_BI) && !skip_rx) {
 		if (!up->dma || handle_rx_dma(up, iir))
 			status = serial8250_rx_chars(up, status);
 	}
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 71f99e921759..c7683beb3412 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -1187,14 +1187,14 @@ static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
 	struct s3c24xx_uart_info *info = ourport->info;
 	struct clk *clk;
 	unsigned long rate;
-	unsigned int cnt, baud, quot, clk_sel, best_quot = 0;
+	unsigned int cnt, baud, quot, best_quot = 0;
 	char clkname[MAX_CLK_NAME_LENGTH];
 	int calc_deviation, deviation = (1 << 30) - 1;
 
-	clk_sel = (ourport->cfg->clk_sel) ? ourport->cfg->clk_sel :
-			ourport->info->def_clk_sel;
 	for (cnt = 0; cnt < info->num_clks; cnt++) {
-		if (!(clk_sel & (1 << cnt)))
+		/* Keep selected clock if provided */
+		if (ourport->cfg->clk_sel &&
+			!(ourport->cfg->clk_sel & (1 << cnt)))
 			continue;
 
 		sprintf(clkname, "clk_uart_baud%d", cnt);
diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c
index 38133eba83a8..b4343c6aa651 100644
--- a/drivers/tty/serial/sifive.c
+++ b/drivers/tty/serial/sifive.c
@@ -618,10 +618,10 @@ static void sifive_serial_shutdown(struct uart_port *port)
  *
  * On the V0 SoC, the UART IP block is derived from the CPU clock source
  * after a synchronous divide-by-two divider, so any CPU clock rate change
- * requires the UART baud rate to be updated.  This presumably could corrupt any
- * serial word currently being transmitted or received.  It would probably
- * be better to stop receives and transmits, then complete the baud rate
- * change, then re-enable them.
+ * requires the UART baud rate to be updated.  This presumably corrupts any
+ * serial word currently being transmitted or received.  In order to avoid
+ * corrupting the output data stream, we drain the transmit queue before
+ * allowing the clock's rate to be changed.
  */
 static int sifive_serial_clk_notifier(struct notifier_block *nb,
 				      unsigned long event, void *data)
@@ -629,6 +629,26 @@ static int sifive_serial_clk_notifier(struct notifier_block *nb,
 	struct clk_notifier_data *cnd = data;
 	struct sifive_serial_port *ssp = notifier_to_sifive_serial_port(nb);
 
+	if (event == PRE_RATE_CHANGE) {
+		/*
+		 * The TX watermark is always set to 1 by this driver, which
+		 * means that the TX busy bit will lower when there are 0 bytes
+		 * left in the TX queue -- in other words, when the TX FIFO is
+		 * empty.
+		 */
+		__ssp_wait_for_xmitr(ssp);
+		/*
+		 * On the cycle the TX FIFO goes empty there is still a full
+		 * UART frame left to be transmitted in the shift register.
+		 * The UART provides no way for software to directly determine
+		 * when that last frame has been transmitted, so we just sleep
+		 * here instead.  As we're not tracking the number of stop bits
+		 * they're just worst cased here.  The rest of the serial
+		 * framing parameters aren't configurable by software.
+		 */
+		udelay(DIV_ROUND_UP(12 * 1000 * 1000, ssp->baud_rate));
+	}
+
 	if (event == POST_RATE_CHANGE && ssp->clkin_rate != cnd->new_rate) {
 		ssp->clkin_rate = cnd->new_rate;
 		__ssp_update_div(ssp);
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 8948970f795e..9359c80fbb9f 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1248,6 +1248,7 @@ static int cdns_uart_console_setup(struct console *co, char *options)
 	int bits = 8;
 	int parity = 'n';
 	int flow = 'n';
+	unsigned long time_out;
 
 	if (!port->membase) {
 		pr_debug("console on " CDNS_UART_TTY_NAME "%i not present\n",
@@ -1258,6 +1259,13 @@ static int cdns_uart_console_setup(struct console *co, char *options)
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 
+	/* Wait for tx_empty before setting up the console */
+	time_out = jiffies + usecs_to_jiffies(TX_TIMEOUT);
+
+	while (time_before(jiffies, time_out) &&
+	       cdns_uart_tx_empty(port) != TIOCSER_TEMT)
+		cpu_relax();
+
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
 
diff --git a/drivers/tty/vcc.c b/drivers/tty/vcc.c
index d2a1e1228c82..9ffd42e333b8 100644
--- a/drivers/tty/vcc.c
+++ b/drivers/tty/vcc.c
@@ -605,6 +605,7 @@ static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	port->index = vcc_table_add(port);
 	if (port->index == -1) {
 		pr_err("VCC: no more TTY indices left for allocation\n");
+		rv = -ENOMEM;
 		goto free_ldc;
 	}