[ARM] S3C24XX: Split serial driver into core and per-cpu drivers

The S3C2410 serial driver in drivers/serial/s3c2410.c has been
growing bigger with the addition of more variants of this hardware
with the growing Samsung SoCs range. As such, it would be
easier to split this code up into a core and per-cpu drivers to
make driver addition easier, and the core smaller.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

1 files changed, 181 insertions, 0 deletions

diff --git a/drivers/serial/s3c2440.c b/drivers/serial/s3c2440.c
new file mode 100644
index 000000000000..38f954bd39c6
--- /dev/null
+++ b/drivers/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) 2003-2005,2008 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 <asm/hardware.h>
+
+#include <asm/plat-s3c/regs-serial.h>
+#include <asm/arch/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_drv = {
+        .probe          = s3c2440_serial_probe,
+        .remove         = s3c24xx_serial_remove,
+        .driver         = {
+                .name   = "s3c2440-uart",
+                .owner  = THIS_MODULE,
+        },
+};
+
+s3c24xx_console_init(&s3c2440_serial_drv, &s3c2440_uart_inf);
+
+static int __init s3c2440_serial_init(void)
+{
+        return s3c24xx_serial_init(&s3c2440_serial_drv, &s3c2440_uart_inf);
+}
+
+static void __exit s3c2440_serial_exit(void)
+{
+        platform_driver_unregister(&s3c2440_serial_drv);
+}
+
+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("GPLi v2");
+MODULE_ALIAS("platform:s3c2440-uart");