arch/arm/mach-omap1/serial.c

   1 /*
   2  * linux/arch/arm/mach-omap1/serial.c
   3  *
   4  * OMAP1 serial support.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/gpio.h>
  11 #include <linux/module.h>
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/irq.h>
  15 #include <linux/delay.h>
  16 #include <linux/serial.h>
  17 #include <linux/tty.h>
  18 #include <linux/serial_8250.h>
  19 #include <linux/serial_reg.h>
  20 #include <linux/clk.h>
  21 #include <linux/io.h>
  22
  23 #include <asm/mach-types.h>
  24
  25 #include <plat/board.h>
  26 #include <plat/mux.h>
  27 #include <plat/fpga.h>
  28
  29 #include "pm.h"
  30
  31 static struct clk * uart1_ck;
  32 static struct clk * uart2_ck;
  33 static struct clk * uart3_ck;
  34
  35 static inline unsigned int omap_serial_in(struct plat_serial8250_port *up,
  36                                           int offset)
  37 {
  38         offset <<= up->regshift;
  39         return (unsigned int)__raw_readb(up->membase + offset);
  40 }
  41
  42 static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset,
  43                                     int value)
  44 {
  45         offset <<= p->regshift;
  46         __raw_writeb(value, p->membase + offset);
  47 }
  48
  49 /*
  50  * Internal UARTs need to be initialized for the 8250 autoconfig to work
  51  * properly. Note that the TX watermark initialization may not be needed
  52  * once the 8250.c watermark handling code is merged.
  53  */
  54 static void __init omap_serial_reset(struct plat_serial8250_port *p)
  55 {
  56         omap_serial_outp(p, UART_OMAP_MDR1,
  57                         UART_OMAP_MDR1_DISABLE);        /* disable UART */
  58         omap_serial_outp(p, UART_OMAP_SCR, 0x08);       /* TX watermark */
  59         omap_serial_outp(p, UART_OMAP_MDR1,
  60                         UART_OMAP_MDR1_16X_MODE);       /* enable UART */
  61
  62         if (!cpu_is_omap15xx()) {
  63                 omap_serial_outp(p, UART_OMAP_SYSC, 0x01);
  64                 while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01));
  65         }
  66 }
  67
  68 static struct plat_serial8250_port serial_platform_data[] = {
  69         {
  70                 .mapbase        = OMAP1_UART1_BASE,
  71                 .irq            = INT_UART1,
  72                 .flags          = UPF_BOOT_AUTOCONF,
  73                 .iotype         = UPIO_MEM,
  74                 .regshift       = 2,
  75                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  76         },
  77         {
  78                 .mapbase        = OMAP1_UART2_BASE,
  79                 .irq            = INT_UART2,
  80                 .flags          = UPF_BOOT_AUTOCONF,
  81                 .iotype         = UPIO_MEM,
  82                 .regshift       = 2,
  83                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  84         },
  85         {
  86                 .mapbase        = OMAP1_UART3_BASE,
  87                 .irq            = INT_UART3,
  88                 .flags          = UPF_BOOT_AUTOCONF,
  89                 .iotype         = UPIO_MEM,
  90                 .regshift       = 2,
  91                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  92         },
  93         { },
  94 };
  95
  96 static struct platform_device serial_device = {
  97         .name                   = "serial8250",
  98         .id                     = PLAT8250_DEV_PLATFORM,
  99         .dev                    = {
 100                 .platform_data  = serial_platform_data,
 101         },
 102 };
 103
 104 /*
 105  * Note that on Innovator-1510 UART2 pins conflict with USB2.
 106  * By default UART2 does not work on Innovator-1510 if you have
 107  * USB OHCI enabled. To use UART2, you must disable USB2 first.
 108  */
 109 void __init omap_serial_init(void)
 110 {
 111         int i;
 112
 113         if (cpu_is_omap7xx()) {
 114                 serial_platform_data[0].regshift = 0;
 115                 serial_platform_data[1].regshift = 0;
 116                 serial_platform_data[0].irq = INT_7XX_UART_MODEM_1;
 117                 serial_platform_data[1].irq = INT_7XX_UART_MODEM_IRDA_2;
 118         }
 119
 120         if (cpu_is_omap15xx()) {
 121                 serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16;
 122                 serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16;
 123                 serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16;
 124         }
 125
 126         for (i = 0; i < ARRAY_SIZE(serial_platform_data) - 1; i++) {
 127
 128                 /* Don't look at UARTs higher than 2 for omap7xx */
 129                 if (cpu_is_omap7xx() && i > 1) {
 130                         serial_platform_data[i].membase = NULL;
 131                         serial_platform_data[i].mapbase = 0;
 132                         continue;
 133                 }
 134
 135                 /* Static mapping, never released */
 136                 serial_platform_data[i].membase =
 137                         ioremap(serial_platform_data[i].mapbase, SZ_2K);
 138                 if (!serial_platform_data[i].membase) {
 139                         printk(KERN_ERR "Could not ioremap uart%i\n", i);
 140                         continue;
 141                 }
 142                 switch (i) {
 143                 case 0:
 144                         uart1_ck = clk_get(NULL, "uart1_ck");
 145                         if (IS_ERR(uart1_ck))
 146                                 printk("Could not get uart1_ck\n");
 147                         else {
 148                                 clk_enable(uart1_ck);
 149                                 if (cpu_is_omap15xx())
 150                                         clk_set_rate(uart1_ck, 12000000);
 151                         }
 152                         break;
 153                 case 1:
 154                         uart2_ck = clk_get(NULL, "uart2_ck");
 155                         if (IS_ERR(uart2_ck))
 156                                 printk("Could not get uart2_ck\n");
 157                         else {
 158                                 clk_enable(uart2_ck);
 159                                 if (cpu_is_omap15xx())
 160                                         clk_set_rate(uart2_ck, 12000000);
 161                                 else
 162                                         clk_set_rate(uart2_ck, 48000000);
 163                         }
 164                         break;
 165                 case 2:
 166                         uart3_ck = clk_get(NULL, "uart3_ck");
 167                         if (IS_ERR(uart3_ck))
 168                                 printk("Could not get uart3_ck\n");
 169                         else {
 170                                 clk_enable(uart3_ck);
 171                                 if (cpu_is_omap15xx())
 172                                         clk_set_rate(uart3_ck, 12000000);
 173                         }
 174                         break;
 175                 }
 176                 omap_serial_reset(&serial_platform_data[i]);
 177         }
 178 }
 179
 180 #ifdef CONFIG_OMAP_SERIAL_WAKE
 181
 182 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id)
 183 {
 184         /* Need to do something with serial port right after wake-up? */
 185         return IRQ_HANDLED;
 186 }
 187
 188 /*
 189  * Reroutes serial RX lines to GPIO lines for the duration of
 190  * sleep to allow waking up the device from serial port even
 191  * in deep sleep.
 192  */
 193 void omap_serial_wake_trigger(int enable)
 194 {
 195         if (!cpu_is_omap16xx())
 196                 return;
 197
 198         if (uart1_ck != NULL) {
 199                 if (enable)
 200                         omap_cfg_reg(V14_16XX_GPIO37);
 201                 else
 202                         omap_cfg_reg(V14_16XX_UART1_RX);
 203         }
 204         if (uart2_ck != NULL) {
 205                 if (enable)
 206                         omap_cfg_reg(R9_16XX_GPIO18);
 207                 else
 208                         omap_cfg_reg(R9_16XX_UART2_RX);
 209         }
 210         if (uart3_ck != NULL) {
 211                 if (enable)
 212                         omap_cfg_reg(L14_16XX_GPIO49);
 213                 else
 214                         omap_cfg_reg(L14_16XX_UART3_RX);
 215         }
 216 }
 217
 218 static void __init omap_serial_set_port_wakeup(int gpio_nr)
 219 {
 220         int ret;
 221
 222         ret = gpio_request(gpio_nr, "UART wake");
 223         if (ret < 0) {
 224                 printk(KERN_ERR "Could not request UART wake GPIO: %i\n",
 225                        gpio_nr);
 226                 return;
 227         }
 228         gpio_direction_input(gpio_nr);
 229         ret = request_irq(gpio_to_irq(gpio_nr), &omap_serial_wake_interrupt,
 230                           IRQF_TRIGGER_RISING, "serial wakeup", NULL);
 231         if (ret) {
 232                 gpio_free(gpio_nr);
 233                 printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n",
 234                        gpio_nr);
 235                 return;
 236         }
 237         enable_irq_wake(gpio_to_irq(gpio_nr));
 238 }
 239
 240 static int __init omap_serial_wakeup_init(void)
 241 {
 242         if (!cpu_is_omap16xx())
 243                 return 0;
 244
 245         if (uart1_ck != NULL)
 246                 omap_serial_set_port_wakeup(37);
 247         if (uart2_ck != NULL)
 248                 omap_serial_set_port_wakeup(18);
 249         if (uart3_ck != NULL)
 250                 omap_serial_set_port_wakeup(49);
 251
 252         return 0;
 253 }
 254 late_initcall(omap_serial_wakeup_init);
 255
 256 #endif  /* CONFIG_OMAP_SERIAL_WAKE */
 257
 258 static int __init omap_init(void)
 259 {
 260         if (!cpu_class_is_omap1())
 261                 return -ENODEV;
 262
 263         return platform_device_register(&serial_device);
 264 }
 265 arch_initcall(omap_init);