drivers/tty/serial/s5pv210.c

   1 /*
   2  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   3  *              http://www.samsung.com/
   4  *
   5  * Based on drivers/serial/s3c6400.c
   6  *
   7  * Driver for Samsung S5PV210 SoC UARTs.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12 */
  13
  14 #include <linux/module.h>
  15 #include <linux/ioport.h>
  16 #include <linux/io.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/init.h>
  19 #include <linux/serial_core.h>
  20 #include <linux/serial.h>
  21 #include <linux/delay.h>
  22
  23 #include <asm/irq.h>
  24 #include <mach/hardware.h>
  25 #include <plat/regs-serial.h>
  26 #include "samsung.h"
  27
  28 static int s5pv210_serial_setsource(struct uart_port *port,
  29                                         struct s3c24xx_uart_clksrc *clk)
  30 {
  31         struct s3c2410_uartcfg *cfg = port->dev->platform_data;
  32         unsigned long ucon = rd_regl(port, S3C2410_UCON);
  33
  34         if (cfg->flags & NO_NEED_CHECK_CLKSRC)
  35                 return 0;
  36
  37         if (strcmp(clk->name, "pclk") == 0)
  38                 ucon &= ~S5PV210_UCON_CLKMASK;
  39         else if (strcmp(clk->name, "uclk1") == 0)
  40                 ucon |= S5PV210_UCON_CLKMASK;
  41         else {
  42                 printk(KERN_ERR "unknown clock source %s\n", clk->name);
  43                 return -EINVAL;
  44         }
  45
  46         wr_regl(port, S3C2410_UCON, ucon);
  47         return 0;
  48 }
  49
  50
  51 static int s5pv210_serial_getsource(struct uart_port *port,
  52                                         struct s3c24xx_uart_clksrc *clk)
  53 {
  54         struct s3c2410_uartcfg *cfg = port->dev->platform_data;
  55         u32 ucon = rd_regl(port, S3C2410_UCON);
  56
  57         clk->divisor = 1;
  58
  59         if (cfg->flags & NO_NEED_CHECK_CLKSRC)
  60                 return 0;
  61
  62         switch (ucon & S5PV210_UCON_CLKMASK) {
  63         case S5PV210_UCON_PCLK:
  64                 clk->name = "pclk";
  65                 break;
  66         case S5PV210_UCON_UCLK:
  67                 clk->name = "uclk1";
  68                 break;
  69         }
  70
  71         return 0;
  72 }
  73
  74 static int s5pv210_serial_resetport(struct uart_port *port,
  75                                         struct s3c2410_uartcfg *cfg)
  76 {
  77         unsigned long ucon = rd_regl(port, S3C2410_UCON);
  78
  79         ucon &= S5PV210_UCON_CLKMASK;
  80         wr_regl(port, S3C2410_UCON,  ucon | cfg->ucon);
  81         wr_regl(port, S3C2410_ULCON, cfg->ulcon);
  82
  83         /* reset both fifos */
  84         wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
  85         wr_regl(port, S3C2410_UFCON, cfg->ufcon);
  86
  87         wr_regl(port, S3C64XX_UINTM, 0xf);
  88         wr_regl(port, S3C64XX_UINTP, 0xf);
  89
  90         /* It is need to delay when reset FIFO register */
  91         udelay(1);
  92
  93         return 0;
  94 }
  95
  96 #define S5PV210_UART_DEFAULT_INFO(fifo_size)                    \
  97                 .name           = "Samsung S5PV210 UART0",      \
  98                 .type           = PORT_S3C6400,                 \
  99                 .fifosize       = fifo_size,                    \
 100                 .has_divslot    = 1,                            \
 101                 .rx_fifomask    = S5PV210_UFSTAT_RXMASK,        \
 102                 .rx_fifoshift   = S5PV210_UFSTAT_RXSHIFT,       \
 103                 .rx_fifofull    = S5PV210_UFSTAT_RXFULL,        \
 104                 .tx_fifofull    = S5PV210_UFSTAT_TXFULL,        \
 105                 .tx_fifomask    = S5PV210_UFSTAT_TXMASK,        \
 106                 .tx_fifoshift   = S5PV210_UFSTAT_TXSHIFT,       \
 107                 .get_clksrc     = s5pv210_serial_getsource,     \
 108                 .set_clksrc     = s5pv210_serial_setsource,     \
 109                 .reset_port     = s5pv210_serial_resetport
 110
 111 static struct s3c24xx_uart_info s5p_port_fifo256 = {
 112         S5PV210_UART_DEFAULT_INFO(256),
 113 };
 114
 115 static struct s3c24xx_uart_info s5p_port_fifo64 = {
 116         S5PV210_UART_DEFAULT_INFO(64),
 117 };
 118
 119 static struct s3c24xx_uart_info s5p_port_fifo16 = {
 120         S5PV210_UART_DEFAULT_INFO(16),
 121 };
 122
 123 static struct s3c24xx_uart_info *s5p_uart_inf[] = {
 124         [0] = &s5p_port_fifo256,
 125         [1] = &s5p_port_fifo64,
 126         [2] = &s5p_port_fifo16,
 127         [3] = &s5p_port_fifo16,
 128 };
 129
 130 /* device management */
 131 static int s5p_serial_probe(struct platform_device *pdev)
 132 {
 133         return s3c24xx_serial_probe(pdev, s5p_uart_inf[pdev->id]);
 134 }
 135
 136 static struct platform_driver s5p_serial_driver = {
 137         .probe          = s5p_serial_probe,
 138         .remove         = __devexit_p(s3c24xx_serial_remove),
 139         .driver         = {
 140                 .name   = "s5pv210-uart",
 141                 .owner  = THIS_MODULE,
 142         },
 143 };
 144
 145 static int __init s5p_serial_init(void)
 146 {
 147         return s3c24xx_serial_init(&s5p_serial_driver, *s5p_uart_inf);
 148 }
 149
 150 static void __exit s5p_serial_exit(void)
 151 {
 152         platform_driver_unregister(&s5p_serial_driver);
 153 }
 154
 155 module_init(s5p_serial_init);
 156 module_exit(s5p_serial_exit);
 157
 158 MODULE_LICENSE("GPL");
 159 MODULE_ALIAS("platform:s5pv210-uart");
 160 MODULE_DESCRIPTION("Samsung S5PV210 UART Driver support");
 161 MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com>");