ARM: clps711x: Add serial driver

This patch adds a simple serial driver for CLPS711X architecture.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

3 files changed, 163 insertions, 0 deletions

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 7eb96edf28..02bc8bfdb3 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -43,6 +43,11 @@ config DRIVER_SERIAL_BLACKFIN
 	default y
 	bool "Blackfin serial driver"
 
+config DRIVER_SERIAL_CLPS711X
+	depends on ARCH_CLPS711X
+	default y
+	bool "CLPS711X serial driver"
+
 config DRIVER_SERIAL_ALTERA
 	depends on NIOS2
 	default y
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index e2d56b96b7..e6f1e22610 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_DRIVER_SERIAL_NETX)		+= serial_netx.o
 obj-$(CONFIG_DRIVER_SERIAL_LINUX_CONSOLE)	+= linux_console.o
 obj-$(CONFIG_DRIVER_SERIAL_MPC5XXX)		+= serial_mpc5xxx.o
 obj-$(CONFIG_DRIVER_SERIAL_BLACKFIN)		+= serial_blackfin.o
+obj-$(CONFIG_DRIVER_SERIAL_CLPS711X)		+= serial_clps711x.o
 obj-$(CONFIG_DRIVER_SERIAL_NS16550)		+= serial_ns16550.o
 obj-$(CONFIG_DRIVER_SERIAL_PL010)		+= serial_pl010.o
 obj-$(CONFIG_DRIVER_SERIAL_S3C)			+= serial_s3c.o
diff --git a/drivers/serial/serial_clps711x.c b/drivers/serial/serial_clps711x.c
new file mode 100644
index 0000000000..21d0b55d3a
--- /dev/null
+++ b/drivers/serial/serial_clps711x.c
@@ -0,0 +1,157 @@
+/*
+ * Simple CLPS711X serial driver
+ *
+ * (C) Copyright 2012 Alexander Shiyan <shc_work@mail.ru>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <init.h>
+#include <io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+#include <mach/clps711x.h>
+
+struct clps711x_uart {
+	void __iomem		*UBRLCR;
+	void __iomem		*SYSCON;
+	void __iomem		*SYSFLG;
+	void __iomem		*UARTDR;
+	struct clk		*uart_clk;
+	struct console_device	cdev;
+};
+
+static int clps711x_setbaudrate(struct console_device *cdev, int baudrate)
+{
+	struct clps711x_uart *s = cdev->dev->priv;
+	int divisor;
+	u32 tmp;
+
+	divisor = (clk_get_rate(s->uart_clk) / 16) / baudrate;
+
+	tmp = readl(s->UBRLCR) & ~UBRLCR_BAUD_MASK;
+	tmp |= divisor - 1;
+	writel(tmp, s->UBRLCR);
+
+	return 0;
+}
+
+static void clps711x_init_port(struct console_device *cdev)
+{
+	struct clps711x_uart *s = cdev->dev->priv;
+	u32 tmp;
+
+	/* Disable the UART */
+	writel(readl(s->SYSCON) & ~SYSCON_UARTEN, s->SYSCON);
+
+	/* Setup Line Control Register */
+	tmp = readl(s->UBRLCR) & UBRLCR_BAUD_MASK;
+	tmp |= UBRLCR_FIFOEN | UBRLCR_WRDLEN8; /* FIFO on, 8N1 mode */
+	writel(tmp, s->UBRLCR);
+
+	/* Set default baudrate on initialization */
+	clps711x_setbaudrate(cdev, CONFIG_BAUDRATE);
+
+	/* Enable the UART */
+	writel(readl(s->SYSCON) | SYSCON_UARTEN, s->SYSCON);
+}
+
+static void clps711x_putc(struct console_device *cdev, char c)
+{
+	struct clps711x_uart *s = cdev->dev->priv;
+
+	/* Wait until there is space in the FIFO */
+	while (readl(s->SYSFLG) & SYSFLG_UTXFF)
+		barrier();
+
+	/* Send the character */
+	writew(c, s->UARTDR);
+}
+
+static int clps711x_getc(struct console_device *cdev)
+{
+	struct clps711x_uart *s = cdev->dev->priv;
+	u16 data;
+
+	/* Wait until there is data in the FIFO */
+	while (readl(s->SYSFLG) & SYSFLG_URXFE)
+		barrier();
+
+	data = readw(s->UARTDR);
+
+	/* Check for an error flag */
+	if (data & (UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR))
+		return -1;
+
+	return (int)data;
+}
+
+static int clps711x_tstc(struct console_device *cdev)
+{
+	struct clps711x_uart *s = cdev->dev->priv;
+
+	return !(readl(s->SYSFLG) & SYSFLG_URXFE);
+}
+
+static void clps711x_flush(struct console_device *cdev)
+{
+	struct clps711x_uart *s = cdev->dev->priv;
+
+	while (readl(s->SYSFLG) & SYSFLG_UBUSY)
+		barrier();
+}
+
+static int clps711x_probe(struct device_d *dev)
+{
+	struct clps711x_uart *s;
+
+	BUG_ON(dev->num_resources != 4);
+
+	s = xzalloc(sizeof(struct clps711x_uart));
+	s->uart_clk = clk_get(dev, NULL);
+	BUG_ON(IS_ERR(s->uart_clk));
+
+	s->UBRLCR = dev_get_mem_region(dev, 0);
+	s->SYSCON = dev_get_mem_region(dev, 1);
+	s->SYSFLG = dev_get_mem_region(dev, 2);
+	s->UARTDR = dev_get_mem_region(dev, 3);
+
+	dev->priv	= s;
+	s->cdev.dev	= dev;
+	s->cdev.f_caps	= CONSOLE_STDIN | CONSOLE_STDOUT | CONSOLE_STDERR;
+	s->cdev.tstc	= clps711x_tstc;
+	s->cdev.putc	= clps711x_putc;
+	s->cdev.getc	= clps711x_getc;
+	s->cdev.flush	= clps711x_flush;
+	s->cdev.setbrg	= clps711x_setbaudrate;
+	clps711x_init_port(&s->cdev);
+
+	return console_register(&s->cdev);
+}
+
+static void clps711x_remove(struct device_d *dev)
+{
+	struct clps711x_uart *s = dev->priv;
+
+	clps711x_flush(&s->cdev);
+	console_unregister(&s->cdev);
+	free(s);
+}
+
+static struct driver_d clps711x_driver = {
+	.name	= "clps711x_serial",
+	.probe	= clps711x_probe,
+	.remove	= clps711x_remove,
+};
+
+static int clps711x_init(void)
+{
+	return platform_driver_register(&clps711x_driver);
+}
+console_initcall(clps711x_init);