x86: ns16550: Rework driver to allow for x86 I/O space

The current implementation fakes a memory-mapped I/O device
at 0x3f8 and 0x2f8, then uses platform read/write functions
to do the actual reading and writing. These platform functions
only exist for the x86 platform; better to move the I/O
routines into the driver and have the driver request I/O ports
using request_ioport_region.

Signed-off-by: Michel Stam <michel@reverze.net>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 107 insertions, 16 deletions

diff --git a/drivers/serial/serial_ns16550.c b/drivers/serial/serial_ns16550.c
index 0c00eb182c..7d22873835 100644
--- a/drivers/serial/serial_ns16550.c
+++ b/drivers/serial/serial_ns16550.c
@@ -47,6 +47,7 @@ struct ns16550_priv {
 	struct console_device cdev;
 	struct NS16550_plat plat;
 	int access_width;
+	int mmio;
 	struct clk *clk;
 	uint32_t fcrval;
 };
@@ -62,6 +63,90 @@ struct ns16550_drvdata {
 };
 
 /**
+ * @brief read system i/o (byte)
+ * @param[in] addr address to read
+ * @param[in] mmio memory i/o space or i/o port space
+ */
+static inline uint8_t ns16550_sys_readb(void __iomem *addr, int mmio)
+{
+	if (mmio)
+		return readb(addr);
+	else
+		return (uint8_t) inb((int) addr);
+}
+
+/**
+ * @brief read system i/o (word)
+ * @param[in] addr address to read
+ * @param[in] mmio memory i/o space or i/o port space
+ */
+static inline uint16_t ns16550_sys_readw(void __iomem *addr, int mmio)
+{
+	if (mmio)
+		return readw(addr);
+	else
+		return (uint16_t) inw((int) addr);
+}
+
+/**
+ * @brief read system i/o (dword)
+ * @param[in] addr address to read
+ * @param[in] mmio memory i/o space or i/o port space
+ */
+static inline uint32_t ns16550_sys_readl(void __iomem *addr, int mmio)
+{
+	if (mmio)
+		return readl(addr);
+	else
+		return (uint32_t) inl((int) addr);
+}
+
+/**
+ * @brief write system i/o (byte)
+ * @param[in] val data to write
+ * @param[in] addr address to write to
+ * @param[in] mmio memory i/o space or i/o port space
+ */
+static inline void ns16550_sys_writeb(uint8_t val, void __iomem *addr,
+				      int mmio)
+{
+	if (mmio)
+		writeb(val, addr);
+	else
+		outb(val, (int) addr);
+}
+
+/**
+ * @brief read system i/o (word)
+ * @param[in] val data to write
+ * @param[in] addr address to write to
+ * @param[in] mmio memory i/o space or i/o port space
+ */
+static inline void ns16550_sys_writew(uint16_t val, void __iomem *addr,
+				      int mmio)
+{
+	if (mmio)
+		writew(val, addr);
+	else
+		outw(val, (int) addr);
+}
+
+/**
+ * @brief read system i/o (dword)
+ * @param[in] val data to write
+ * @param[in] addr address to write to
+ * @param[in] mmio memory i/o space or i/o port space
+ */
+static inline void ns16550_sys_writel(uint32_t val, void __iomem *addr,
+				      int mmio)
+{
+	if (mmio)
+		writel(val, addr);
+	else
+		outl(val, (int) addr);
+}
+
+/**
  * @brief read register
  *
  * @param[in] cdev pointer to console device
@@ -78,16 +163,13 @@ static uint32_t ns16550_read(struct console_device *cdev, uint32_t off)
 
 	off <<= plat->shift;
 
-	if (plat->reg_read)
-		return plat->reg_read((unsigned long)dev->priv, off);
-
 	switch (width) {
 	case IORESOURCE_MEM_8BIT:
-		return readb(dev->priv + off);
+		return ns16550_sys_readb(dev->priv + off, priv->mmio);
 	case IORESOURCE_MEM_16BIT:
-		return readw(dev->priv + off);
+		return ns16550_sys_readw(dev->priv + off, priv->mmio);
 	case IORESOURCE_MEM_32BIT:
-		return readl(dev->priv + off);
+		return ns16550_sys_readl(dev->priv + off, priv->mmio);
 	}
 	return -1;
 }
@@ -109,20 +191,15 @@ static void ns16550_write(struct console_device *cdev, uint32_t val,
 
 	off <<= plat->shift;
 
-	if (plat->reg_write) {
-		plat->reg_write(val, (unsigned long)dev->priv, off);
-		return;
-	}
-
 	switch (width) {
 	case IORESOURCE_MEM_8BIT:
-		writeb(val & 0xff, dev->priv + off);
+		ns16550_sys_writeb(val & 0xff, dev->priv + off, priv->mmio);
 		break;
 	case IORESOURCE_MEM_16BIT:
-		writew(val & 0xffff, dev->priv + off);
+		ns16550_sys_writew(val & 0xffff, dev->priv + off, priv->mmio);
 		break;
 	case IORESOURCE_MEM_32BIT:
-		writel(val, dev->priv + off);
+		ns16550_sys_writel(val, dev->priv + off, priv->mmio);
 		break;
 	}
 }
@@ -293,16 +370,30 @@ static int ns16550_probe(struct device_d *dev)
 	struct console_device *cdev;
 	struct NS16550_plat *plat = (struct NS16550_plat *)dev->platform_data;
 	struct ns16550_drvdata *devtype;
+	struct resource *res;
 	int ret;
 
 	ret = dev_get_drvdata(dev, (unsigned long *)&devtype);
 	if (ret)
 		devtype = &ns16550_drvdata;
 
-	dev->priv = dev_request_mem_region(dev, 0);
-
 	priv = xzalloc(sizeof(*priv));
 
+	res = dev_get_resource(dev, IORESOURCE_MEM, 0);
+	priv->mmio = (res != NULL);
+	if (res) {
+		res = request_iomem_region(dev_name(dev), res->start, res->end);
+	} else {
+		res = dev_get_resource(dev, IORESOURCE_IO, 0);
+		if (res)
+			res = request_ioport_region(dev_name(dev), res->start,
+						    res->end);
+	}
+	if (!res)
+		goto err;
+	dev->priv = (void __force __iomem *) res->start;
+
+
 	if (plat)
 		priv->plat = *plat;
 	else