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path: root/drivers/tty/serial/s3c2440.c
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Diffstat (limited to 'drivers/tty/serial/s3c2440.c')
-rw-r--r--drivers/tty/serial/s3c2440.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/tty/serial/s3c2440.c b/drivers/tty/serial/s3c2440.c
new file mode 100644
index 000000000000..094cc3904b13
--- /dev/null
+++ b/drivers/tty/serial/s3c2440.c
@@ -0,0 +1,181 @@
+/* linux/drivers/serial/s3c2440.c
+ *
+ * Driver for Samsung S3C2440 and S3C2442 SoC onboard UARTs.
+ *
+ * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
+ * http://armlinux.simtec.co.uk/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+
+#include <asm/irq.h>
+#include <mach/hardware.h>
+
+#include <plat/regs-serial.h>
+#include <mach/regs-gpio.h>
+
+#include "samsung.h"
+
+
+static int s3c2440_serial_setsource(struct uart_port *port,
+ struct s3c24xx_uart_clksrc *clk)
+{
+ unsigned long ucon = rd_regl(port, S3C2410_UCON);
+
+ /* todo - proper fclk<>nonfclk switch. */
+
+ ucon &= ~S3C2440_UCON_CLKMASK;
+
+ if (strcmp(clk->name, "uclk") == 0)
+ ucon |= S3C2440_UCON_UCLK;
+ else if (strcmp(clk->name, "pclk") == 0)
+ ucon |= S3C2440_UCON_PCLK;
+ else if (strcmp(clk->name, "fclk") == 0)
+ ucon |= S3C2440_UCON_FCLK;
+ else {
+ printk(KERN_ERR "unknown clock source %s\n", clk->name);
+ return -EINVAL;
+ }
+
+ wr_regl(port, S3C2410_UCON, ucon);
+ return 0;
+}
+
+
+static int s3c2440_serial_getsource(struct uart_port *port,
+ struct s3c24xx_uart_clksrc *clk)
+{
+ unsigned long ucon = rd_regl(port, S3C2410_UCON);
+ unsigned long ucon0, ucon1, ucon2;
+
+ switch (ucon & S3C2440_UCON_CLKMASK) {
+ case S3C2440_UCON_UCLK:
+ clk->divisor = 1;
+ clk->name = "uclk";
+ break;
+
+ case S3C2440_UCON_PCLK:
+ case S3C2440_UCON_PCLK2:
+ clk->divisor = 1;
+ clk->name = "pclk";
+ break;
+
+ case S3C2440_UCON_FCLK:
+ /* the fun of calculating the uart divisors on
+ * the s3c2440 */
+
+ ucon0 = __raw_readl(S3C24XX_VA_UART0 + S3C2410_UCON);
+ ucon1 = __raw_readl(S3C24XX_VA_UART1 + S3C2410_UCON);
+ ucon2 = __raw_readl(S3C24XX_VA_UART2 + S3C2410_UCON);
+
+ printk("ucons: %08lx, %08lx, %08lx\n", ucon0, ucon1, ucon2);
+
+ ucon0 &= S3C2440_UCON0_DIVMASK;
+ ucon1 &= S3C2440_UCON1_DIVMASK;
+ ucon2 &= S3C2440_UCON2_DIVMASK;
+
+ if (ucon0 != 0) {
+ clk->divisor = ucon0 >> S3C2440_UCON_DIVSHIFT;
+ clk->divisor += 6;
+ } else if (ucon1 != 0) {
+ clk->divisor = ucon1 >> S3C2440_UCON_DIVSHIFT;
+ clk->divisor += 21;
+ } else if (ucon2 != 0) {
+ clk->divisor = ucon2 >> S3C2440_UCON_DIVSHIFT;
+ clk->divisor += 36;
+ } else {
+ /* manual calims 44, seems to be 9 */
+ clk->divisor = 9;
+ }
+
+ clk->name = "fclk";
+ break;
+ }
+
+ return 0;
+}
+
+static int s3c2440_serial_resetport(struct uart_port *port,
+ struct s3c2410_uartcfg *cfg)
+{
+ unsigned long ucon = rd_regl(port, S3C2410_UCON);
+
+ dbg("s3c2440_serial_resetport: port=%p (%08lx), cfg=%p\n",
+ port, port->mapbase, cfg);
+
+ /* ensure we don't change the clock settings... */
+
+ ucon &= (S3C2440_UCON0_DIVMASK | (3<<10));
+
+ wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
+ wr_regl(port, S3C2410_ULCON, cfg->ulcon);
+
+ /* reset both fifos */
+
+ wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
+ wr_regl(port, S3C2410_UFCON, cfg->ufcon);
+
+ return 0;
+}
+
+static struct s3c24xx_uart_info s3c2440_uart_inf = {
+ .name = "Samsung S3C2440 UART",
+ .type = PORT_S3C2440,
+ .fifosize = 64,
+ .rx_fifomask = S3C2440_UFSTAT_RXMASK,
+ .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
+ .rx_fifofull = S3C2440_UFSTAT_RXFULL,
+ .tx_fifofull = S3C2440_UFSTAT_TXFULL,
+ .tx_fifomask = S3C2440_UFSTAT_TXMASK,
+ .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
+ .get_clksrc = s3c2440_serial_getsource,
+ .set_clksrc = s3c2440_serial_setsource,
+ .reset_port = s3c2440_serial_resetport,
+};
+
+/* device management */
+
+static int s3c2440_serial_probe(struct platform_device *dev)
+{
+ dbg("s3c2440_serial_probe: dev=%p\n", dev);
+ return s3c24xx_serial_probe(dev, &s3c2440_uart_inf);
+}
+
+static struct platform_driver s3c2440_serial_driver = {
+ .probe = s3c2440_serial_probe,
+ .remove = __devexit_p(s3c24xx_serial_remove),
+ .driver = {
+ .name = "s3c2440-uart",
+ .owner = THIS_MODULE,
+ },
+};
+
+s3c24xx_console_init(&s3c2440_serial_driver, &s3c2440_uart_inf);
+
+static int __init s3c2440_serial_init(void)
+{
+ return s3c24xx_serial_init(&s3c2440_serial_driver, &s3c2440_uart_inf);
+}
+
+static void __exit s3c2440_serial_exit(void)
+{
+ platform_driver_unregister(&s3c2440_serial_driver);
+}
+
+module_init(s3c2440_serial_init);
+module_exit(s3c2440_serial_exit);
+
+MODULE_DESCRIPTION("Samsung S3C2440,S3C2442 SoC Serial port driver");
+MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:s3c2440-uart");