drivers/tty/serial/s3c24a0.c

   1 /*
   2  * Driver for Samsung S3C24A0 SoC onboard UARTs.
   3  *
   4  * Based on drivers/serial/s3c2410.c
   5  *
   6  * Author: Sandeep Patil <sandeep.patil@azingo.com>
   7  *
   8  * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
   9  *      http://armlinux.simtec.co.uk/
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14 */
  15
  16 #include <linux/module.h>
  17 #include <linux/ioport.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/init.h>
  20 #include <linux/serial_core.h>
  21 #include <linux/serial.h>
  22 #include <linux/io.h>
  23 #include <linux/irq.h>
  24
  25 #include <mach/hardware.h>
  26
  27 #include <plat/regs-serial.h>
  28 #include <mach/regs-gpio.h>
  29
  30 #include "samsung.h"
  31
  32 static int s3c24a0_serial_setsource(struct uart_port *port,
  33                                     struct s3c24xx_uart_clksrc *clk)
  34 {
  35         unsigned long ucon = rd_regl(port, S3C2410_UCON);
  36
  37         if (strcmp(clk->name, "uclk") == 0)
  38                 ucon |= S3C2410_UCON_UCLK;
  39         else
  40                 ucon &= ~S3C2410_UCON_UCLK;
  41
  42         wr_regl(port, S3C2410_UCON, ucon);
  43         return 0;
  44 }
  45
  46 static int s3c24a0_serial_getsource(struct uart_port *port,
  47                                     struct s3c24xx_uart_clksrc *clk)
  48 {
  49         unsigned long ucon = rd_regl(port, S3C2410_UCON);
  50
  51         clk->divisor = 1;
  52         clk->name = (ucon & S3C2410_UCON_UCLK) ? "uclk" : "pclk";
  53
  54         return 0;
  55 }
  56
  57 static int s3c24a0_serial_resetport(struct uart_port *port,
  58                                     struct s3c2410_uartcfg *cfg)
  59 {
  60         dbg("s3c24a0_serial_resetport: port=%p (%08lx), cfg=%p\n",
  61             port, port->mapbase, cfg);
  62
  63         wr_regl(port, S3C2410_UCON,  cfg->ucon);
  64         wr_regl(port, S3C2410_ULCON, cfg->ulcon);
  65
  66         /* reset both fifos */
  67
  68         wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
  69         wr_regl(port, S3C2410_UFCON, cfg->ufcon);
  70
  71         return 0;
  72 }
  73
  74 static struct s3c24xx_uart_info s3c24a0_uart_inf = {
  75         .name           = "Samsung S3C24A0 UART",
  76         .type           = PORT_S3C2410,
  77         .fifosize       = 16,
  78         .rx_fifomask    = S3C24A0_UFSTAT_RXMASK,
  79         .rx_fifoshift   = S3C24A0_UFSTAT_RXSHIFT,
  80         .rx_fifofull    = S3C24A0_UFSTAT_RXFULL,
  81         .tx_fifofull    = S3C24A0_UFSTAT_TXFULL,
  82         .tx_fifomask    = S3C24A0_UFSTAT_TXMASK,
  83         .tx_fifoshift   = S3C24A0_UFSTAT_TXSHIFT,
  84         .get_clksrc     = s3c24a0_serial_getsource,
  85         .set_clksrc     = s3c24a0_serial_setsource,
  86         .reset_port     = s3c24a0_serial_resetport,
  87 };
  88
  89 static int s3c24a0_serial_probe(struct platform_device *dev)
  90 {
  91         return s3c24xx_serial_probe(dev, &s3c24a0_uart_inf);
  92 }
  93
  94 static struct platform_driver s3c24a0_serial_driver = {
  95         .probe          = s3c24a0_serial_probe,
  96         .remove         = __devexit_p(s3c24xx_serial_remove),
  97         .driver         = {
  98                 .name   = "s3c24a0-uart",
  99                 .owner  = THIS_MODULE,
 100         },
 101 };
 102
 103 s3c24xx_console_init(&s3c24a0_serial_driver, &s3c24a0_uart_inf);
 104
 105 static int __init s3c24a0_serial_init(void)
 106 {
 107         return s3c24xx_serial_init(&s3c24a0_serial_driver, &s3c24a0_uart_inf);
 108 }
 109
 110 static void __exit s3c24a0_serial_exit(void)
 111 {
 112         platform_driver_unregister(&s3c24a0_serial_driver);
 113 }
 114
 115 module_init(s3c24a0_serial_init);
 116 module_exit(s3c24a0_serial_exit);
 117