1 files changed, 115 insertions, 70 deletions

diff --git a/drivers/serial/serial_ns16550.c b/drivers/serial/serial_ns16550.c
index f7cab8db4b..1b1692658f 100644
--- a/drivers/serial/serial_ns16550.c
+++ b/drivers/serial/serial_ns16550.c
@@ -40,6 +40,10 @@ struct ns16550_priv {
 	void (*write_reg)(struct ns16550_priv *, uint8_t val, unsigned offset);
 	uint8_t (*read_reg)(struct ns16550_priv *, unsigned offset);
 	const char *access_type;
+
+	bool rs485_mode;
+	bool rs485_rts_active_low;
+	bool rs485_rx_during_tx;
 };
 
 struct ns16550_drvdata {
@@ -242,14 +246,10 @@ static void ns16550_jz_init_port(struct console_device *cdev)
 	ns16550_serial_init_port(cdev);
 }
 
-#define BCM2836_AUX_CLOCK_ENB 0x3f215004 /* BCM2835 AUX Clock enable register */
-#define BCM2836_AUX_CLOCK_EN_UART BIT(0) /* Bit 0 enables the Miniuart */
-
 static void rpi_init_port(struct console_device *cdev)
 {
 	struct ns16550_priv *priv = to_ns16550_priv(cdev);
 
-	writeb(BCM2836_AUX_CLOCK_EN_UART, BCM2836_AUX_CLOCK_ENB);
 	priv->plat.shift = 2;
 	/*
 	 * We double the clock rate since the 16550 will divide by 16
@@ -269,9 +269,37 @@ static void rpi_init_port(struct console_device *cdev)
  */
 static void ns16550_putc(struct console_device *cdev, char c)
 {
-	/* Loop Doing Nothing */
-	while ((ns16550_read(cdev, lsr) & LSR_THRE) == 0) ;
+	struct ns16550_priv *priv = to_ns16550_priv(cdev);
+
+	/* wait until FIFO can accept at least one byte */
+	while ((ns16550_read(cdev, lsr) & (LSR_THRE)) != (LSR_THRE))
+		;
+
+	if (priv->rs485_mode) {
+		if (priv->rs485_rts_active_low)
+			ns16550_write(cdev, MCR_RTS, mcr);
+		else
+			ns16550_write(cdev, 0, mcr);
+
+		if (!priv->rs485_rx_during_tx)
+			ns16550_write(cdev, CNTL_TXEN, cntl);
+	}
+
 	ns16550_write(cdev, c, thr);
+
+	if (priv->rs485_mode) {
+		/* wait until FIFO is cleared*/
+		while ((ns16550_read(cdev, lsr) & (LSR_EMPTY)) != (LSR_EMPTY))
+			;
+
+		if (priv->rs485_rts_active_low)
+			ns16550_write(cdev, 0, mcr);
+		else
+			ns16550_write(cdev, MCR_RTS, mcr);
+
+		if (!priv->rs485_rx_during_tx)
+			ns16550_write(cdev, CNTL_TXEN | CNTL_RXEN, cntl);
+	}
 }
 
 /**
@@ -311,13 +339,13 @@ static void ns16550_flush(struct console_device *cdev)
 	while ((ns16550_read(cdev, lsr) & LSR_TEMT) == 0) ;
 }
 
-static void ns16550_probe_dt(struct device_d *dev, struct ns16550_priv *priv)
+static void ns16550_probe_dt(struct device *dev, struct ns16550_priv *priv)
 {
-	struct device_node *np = dev->device_node;
+	struct device_node *np = dev_of_node(dev);
 	u32 offset;
 	u32 width = 1;
 
-	if (!IS_ENABLED(CONFIG_OFDEVICE))
+	if (!np)
 		return;
 
 	of_property_read_u32(np, "clock-frequency", &priv->plat.clock);
@@ -325,6 +353,12 @@ static void ns16550_probe_dt(struct device_d *dev, struct ns16550_priv *priv)
 		priv->mmiobase += offset;
 	of_property_read_u32(np, "reg-shift", &priv->plat.shift);
 	of_property_read_u32(np, "reg-io-width", &width);
+	priv->rs485_rts_active_low =
+		of_property_read_bool(np, "rs485-rts-active-low");
+	priv->rs485_mode =
+		of_property_read_bool(np, "linux,rs485-enabled-at-boot-time");
+	priv->rs485_rx_during_tx =
+		of_property_read_bool(np, "rs485-rx-during-tx");
 
 	switch (width) {
 	case 1:
@@ -372,7 +406,7 @@ static __maybe_unused struct ns16550_drvdata omap_drvdata = {
 	.linux_earlycon_name = "omap8250",
 };
 
-static __maybe_unused struct ns16550_drvdata am43xx_drvdata = {
+static __maybe_unused struct ns16550_drvdata omap_clk48m_drvdata = {
 	.init_port = ns16550_omap_init_port,
 	.linux_console_name = "ttyO",
 	.clk_default = 48000000,
@@ -389,23 +423,51 @@ static __maybe_unused struct ns16550_drvdata rpi_drvdata = {
 	.linux_earlycon_name = "bcm2835aux",
 };
 
-static int ns16550_init_iomem(struct device_d *dev, struct ns16550_priv *priv)
+/**
+ * @return the requested resource to be properly released in case probe fail
+ */
+static struct resource *ns16550_init_iores(struct device *dev, struct ns16550_priv *priv)
 {
-	struct resource *iores;
 	struct resource *res;
-	int width;
+	struct resource *iores;
+	unsigned long flags;
 
 	res = dev_get_resource(dev, IORESOURCE_MEM, 0);
 	if (IS_ERR(res))
-		return PTR_ERR(res);
+		res = dev_get_resource(dev, IORESOURCE_IO, 0);
+	if (IS_ERR(res))
+		return res;
+
+	flags = res->flags & (IORESOURCE_MEM_TYPE_MASK | IORESOURCE_IO);
 
-	iores = dev_request_mem_resource(dev, 0);
+	if (flags & IORESOURCE_IO)
+		iores = request_ioport_region(dev_name(dev), res->start, res->end);
+	else
+		iores = request_iomem_region(dev_name(dev), res->start, res->end);
 	if (IS_ERR(iores))
-		return PTR_ERR(iores);
-	priv->mmiobase = IOMEM(iores->start);
+		return iores;
 
-	width = res->flags & IORESOURCE_MEM_TYPE_MASK;
-	switch (width) {
+	if (flags & IORESOURCE_IO)
+		priv->iobase = iores->start;
+	else
+		priv->mmiobase = IOMEM(iores->start);
+
+	switch (flags) {
+	case IORESOURCE_IO | IORESOURCE_MEM_8BIT:
+		priv->read_reg = ns16550_read_reg_ioport_8;
+		priv->write_reg = ns16550_write_reg_ioport_8;
+		priv->access_type = "io";
+		break;
+	case IORESOURCE_IO | IORESOURCE_MEM_16BIT:
+		priv->read_reg = ns16550_read_reg_ioport_16;
+		priv->write_reg = ns16550_write_reg_ioport_16;
+		priv->access_type = "io";
+		break;
+	case IORESOURCE_IO | IORESOURCE_MEM_32BIT:
+		priv->read_reg = ns16550_read_reg_ioport_32;
+		priv->write_reg = ns16550_write_reg_ioport_32;
+		priv->access_type = "io";
+		break;
 	case IORESOURCE_MEM_8BIT:
 		priv->read_reg = ns16550_read_reg_mmio_8;
 		priv->write_reg = ns16550_write_reg_mmio_8;
@@ -423,43 +485,7 @@ static int ns16550_init_iomem(struct device_d *dev, struct ns16550_priv *priv)
 		break;
 	}
 
-	return 0;
-}
-
-static int ns16550_init_ioport(struct device_d *dev, struct ns16550_priv *priv)
-{
-	struct resource *res;
-	int width;
-
-	res = dev_get_resource(dev, IORESOURCE_IO, 0);
-	if (IS_ERR(res))
-		return PTR_ERR(res);
-
-	res = request_ioport_region(dev_name(dev), res->start, res->end);
-	if (IS_ERR(res))
-		return PTR_ERR(res);
-
-	priv->iobase = res->start;
-
-	width = res->flags & IORESOURCE_MEM_TYPE_MASK;
-	switch (width) {
-	case IORESOURCE_MEM_8BIT:
-		priv->read_reg = ns16550_read_reg_ioport_8;
-		priv->write_reg = ns16550_write_reg_ioport_8;
-		break;
-	case IORESOURCE_MEM_16BIT:
-		priv->read_reg = ns16550_read_reg_ioport_16;
-		priv->write_reg = ns16550_write_reg_ioport_16;
-		break;
-	case IORESOURCE_MEM_32BIT:
-		priv->read_reg = ns16550_read_reg_ioport_32;
-		priv->write_reg = ns16550_write_reg_ioport_32;
-		break;
-	}
-
-	priv->access_type = "io";
-
-	return 0;
+	return iores;
 }
 
 /**
@@ -471,24 +497,24 @@ static int ns16550_init_ioport(struct device_d *dev, struct ns16550_priv *priv)
  *	   ENOMEM if calloc failed
  *	   else return result of console_register
  */
-static int ns16550_probe(struct device_d *dev)
+static int ns16550_probe(struct device *dev)
 {
 	struct ns16550_priv *priv;
 	struct console_device *cdev;
 	struct NS16550_plat *plat = (struct NS16550_plat *)dev->platform_data;
 	const struct ns16550_drvdata *devtype;
+	struct resource *iores;
 	int ret;
 
 	devtype = device_get_match_data(dev) ?: &ns16550_drvdata;
 
 	priv = xzalloc(sizeof(*priv));
 
-	ret = ns16550_init_iomem(dev, priv);
-	if (ret)
-		ret = ns16550_init_ioport(dev, priv);
-
-	if (ret)
-		return ret;
+	iores = ns16550_init_iores(dev, priv);
+	if (IS_ERR(iores)) {
+		ret = PTR_ERR(iores);
+		goto err;
+	}
 
 	if (plat)
 		priv->plat = *plat;
@@ -503,16 +529,18 @@ static int ns16550_probe(struct device_d *dev)
 		if (IS_ERR(priv->clk)) {
 			ret = PTR_ERR(priv->clk);
 			dev_err(dev, "failed to get clk (%d)\n", ret);
-			goto err;
+			goto release_region;
 		}
-		clk_enable(priv->clk);
+		ret = clk_enable(priv->clk);
+		if (ret)
+			goto clk_put;
 		priv->plat.clock = clk_get_rate(priv->clk);
 	}
 
 	if (priv->plat.clock == 0) {
 		dev_err(dev, "no valid clockrate\n");
 		ret = -EINVAL;
-		goto err;
+		goto clk_disable;
 	}
 
 	cdev = &priv->cdev;
@@ -532,8 +560,18 @@ static int ns16550_probe(struct device_d *dev)
 
 	devtype->init_port(cdev);
 
-	return console_register(cdev);
+	ret = console_register(cdev);
+	if (ret)
+		goto clk_disable;
 
+	return 0;
+
+clk_disable:
+	clk_disable(priv->clk);
+clk_put:
+	clk_put(priv->clk);
+release_region:
+	release_region(iores);
 err:
 	free(priv);
 
@@ -553,6 +591,12 @@ static struct of_device_id ns16550_serial_dt_ids[] = {
 	}, {
 		.compatible = "nvidia,tegra20-uart",
 	},
+#if IS_ENABLED(CONFIG_ARCH_K3)
+	{
+		.compatible = "ti,am654-uart",
+		.data = &omap_clk48m_drvdata,
+	},
+#endif
 #if IS_ENABLED(CONFIG_ARCH_OMAP)
 	{
 		.compatible = "ti,omap2-uart",
@@ -565,7 +609,7 @@ static struct of_device_id ns16550_serial_dt_ids[] = {
 		.data = &omap_drvdata,
 	}, {
 		.compatible = "ti,am4372-uart",
-		.data = &am43xx_drvdata,
+		.data = &omap_clk48m_drvdata,
 	},
 #endif
 #if IS_ENABLED(CONFIG_MACH_MIPS_XBURST)
@@ -584,11 +628,12 @@ static struct of_device_id ns16550_serial_dt_ids[] = {
 		/* sentinel */
 	},
 };
+MODULE_DEVICE_TABLE(of, ns16550_serial_dt_ids);
 
 static __maybe_unused struct platform_device_id ns16550_serial_ids[] = {
 	{
 		.name = "omap-uart",
-		.driver_data = (unsigned long)&omap_drvdata,
+		.driver_data = (unsigned long)&omap_clk48m_drvdata,
 	}, {
 		/* sentinel */
 	},
@@ -597,7 +642,7 @@ static __maybe_unused struct platform_device_id ns16550_serial_ids[] = {
 /**
  * @brief Driver registration structure
  */
-static struct driver_d ns16550_serial_driver = {
+static struct driver ns16550_serial_driver = {
 	.name = "ns16550_serial",
 	.probe = ns16550_probe,
 	.of_compatible = DRV_OF_COMPAT(ns16550_serial_dt_ids),