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
  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 <mach/gpio.h>
  28 #include <plat/fpga.h>
  29
  30 static struct clk * uart1_ck;
  31 static struct clk * uart2_ck;
  32 static struct clk * uart3_ck;
  33
  34 static inline unsigned int omap_serial_in(struct plat_serial8250_port *up,
  35                                           int offset)
  36 {
  37         offset <<= up->regshift;
  38         return (unsigned int)__raw_readb(up->membase + offset);
  39 }
  40
  41 static inline void omap_serial_outp(struct plat_serial8250_port *p, int offset,
  42                                     int value)
  43 {
  44         offset <<= p->regshift;
  45         __raw_writeb(value, p->membase + offset);
  46 }
  47
  48 /*
  49  * Internal UARTs need to be initialized for the 8250 autoconfig to work
  50  * properly. Note that the TX watermark initialization may not be needed
  51  * once the 8250.c watermark handling code is merged.
  52  */
  53 static void __init omap_serial_reset(struct plat_serial8250_port *p)
  54 {
  55         omap_serial_outp(p, UART_OMAP_MDR1, 0x07);      /* disable UART */
  56         omap_serial_outp(p, UART_OMAP_SCR, 0x08);       /* TX watermark */
  57         omap_serial_outp(p, UART_OMAP_MDR1, 0x00);      /* enable UART */
  58
  59         if (!cpu_is_omap15xx()) {
  60                 omap_serial_outp(p, UART_OMAP_SYSC, 0x01);
  61                 while (!(omap_serial_in(p, UART_OMAP_SYSC) & 0x01));
  62         }
  63 }
  64
  65 static struct plat_serial8250_port serial_platform_data[] = {
  66         {
  67                 .mapbase        = OMAP1_UART1_BASE,
  68                 .irq            = INT_UART1,
  69                 .flags          = UPF_BOOT_AUTOCONF,
  70                 .iotype         = UPIO_MEM,
  71                 .regshift       = 2,
  72                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  73         },
  74         {
  75                 .mapbase        = OMAP1_UART2_BASE,
  76                 .irq            = INT_UART2,
  77                 .flags          = UPF_BOOT_AUTOCONF,
  78                 .iotype         = UPIO_MEM,
  79                 .regshift       = 2,
  80                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  81         },
  82         {
  83                 .mapbase        = OMAP1_UART3_BASE,
  84                 .irq            = INT_UART3,
  85                 .flags          = UPF_BOOT_AUTOCONF,
  86                 .iotype         = UPIO_MEM,
  87                 .regshift       = 2,
  88                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  89         },
  90         { },
  91 };
  92
  93 static struct platform_device serial_device = {
  94         .name                   = "serial8250",
  95         .id                     = PLAT8250_DEV_PLATFORM,
  96         .dev                    = {
  97                 .platform_data  = serial_platform_data,
  98         },
  99 };
 100
 101 /*
 102  * Note that on Innovator-1510 UART2 pins conflict with USB2.
 103  * By default UART2 does not work on Innovator-1510 if you have
 104  * USB OHCI enabled. To use UART2, you must disable USB2 first.
 105  */
 106 void __init omap_serial_init(void)
 107 {
 108         int i;
 109
 110         if (cpu_is_omap7xx()) {
 111                 serial_platform_data[0].regshift = 0;
 112                 serial_platform_data[1].regshift = 0;
 113                 serial_platform_data[0].irq = INT_7XX_UART_MODEM_1;
 114                 serial_platform_data[1].irq = INT_7XX_UART_MODEM_IRDA_2;
 115         }
 116
 117         if (cpu_is_omap15xx()) {
 118                 serial_platform_data[0].uartclk = OMAP1510_BASE_BAUD * 16;
 119                 serial_platform_data[1].uartclk = OMAP1510_BASE_BAUD * 16;
 120                 serial_platform_data[2].uartclk = OMAP1510_BASE_BAUD * 16;
 121         }
 122
 123         for (i = 0; i < ARRAY_SIZE(serial_platform_data) - 1; i++) {
 124
 125                 /* Static mapping, never released */
 126                 serial_platform_data[i].membase =
 127                         ioremap(serial_platform_data[i].mapbase, SZ_2K);
 128                 if (!serial_platform_data[i].membase) {
 129                         printk(KERN_ERR "Could not ioremap uart%i\n", i);
 130                         continue;
 131                 }
 132                 switch (i) {
 133                 case 0:
 134                         uart1_ck = clk_get(NULL, "uart1_ck");
 135                         if (IS_ERR(uart1_ck))
 136                                 printk("Could not get uart1_ck\n");
 137                         else {
 138                                 clk_enable(uart1_ck);
 139                                 if (cpu_is_omap15xx())
 140                                         clk_set_rate(uart1_ck, 12000000);
 141                         }
 142                         break;
 143                 case 1:
 144                         uart2_ck = clk_get(NULL, "uart2_ck");
 145                         if (IS_ERR(uart2_ck))
 146                                 printk("Could not get uart2_ck\n");
 147                         else {
 148                                 clk_enable(uart2_ck);
 149                                 if (cpu_is_omap15xx())
 150                                         clk_set_rate(uart2_ck, 12000000);
 151                                 else
 152                                         clk_set_rate(uart2_ck, 48000000);
 153                         }
 154                         break;
 155                 case 2:
 156                         uart3_ck = clk_get(NULL, "uart3_ck");
 157                         if (IS_ERR(uart3_ck))
 158                                 printk("Could not get uart3_ck\n");
 159                         else {
 160                                 clk_enable(uart3_ck);
 161                                 if (cpu_is_omap15xx())
 162                                         clk_set_rate(uart3_ck, 12000000);
 163                         }
 164                         break;
 165                 }
 166                 omap_serial_reset(&serial_platform_data[i]);
 167         }
 168 }
 169
 170 #ifdef CONFIG_OMAP_SERIAL_WAKE
 171
 172 static irqreturn_t omap_serial_wake_interrupt(int irq, void *dev_id)
 173 {
 174         /* Need to do something with serial port right after wake-up? */
 175         return IRQ_HANDLED;
 176 }
 177
 178 /*
 179  * Reroutes serial RX lines to GPIO lines for the duration of
 180  * sleep to allow waking up the device from serial port even
 181  * in deep sleep.
 182  */
 183 void omap_serial_wake_trigger(int enable)
 184 {
 185         if (!cpu_is_omap16xx())
 186                 return;
 187
 188         if (uart1_ck != NULL) {
 189                 if (enable)
 190                         omap_cfg_reg(V14_16XX_GPIO37);
 191                 else
 192                         omap_cfg_reg(V14_16XX_UART1_RX);
 193         }
 194         if (uart2_ck != NULL) {
 195                 if (enable)
 196                         omap_cfg_reg(R9_16XX_GPIO18);
 197                 else
 198                         omap_cfg_reg(R9_16XX_UART2_RX);
 199         }
 200         if (uart3_ck != NULL) {
 201                 if (enable)
 202                         omap_cfg_reg(L14_16XX_GPIO49);
 203                 else
 204                         omap_cfg_reg(L14_16XX_UART3_RX);
 205         }
 206 }
 207
 208 static void __init omap_serial_set_port_wakeup(int gpio_nr)
 209 {
 210         int ret;
 211
 212         ret = gpio_request(gpio_nr, "UART wake");
 213         if (ret < 0) {
 214                 printk(KERN_ERR "Could not request UART wake GPIO: %i\n",
 215                        gpio_nr);
 216                 return;
 217         }
 218         gpio_direction_input(gpio_nr);
 219         ret = request_irq(gpio_to_irq(gpio_nr), &omap_serial_wake_interrupt,
 220                           IRQF_TRIGGER_RISING, "serial wakeup", NULL);
 221         if (ret) {
 222                 gpio_free(gpio_nr);
 223                 printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n",
 224                        gpio_nr);
 225                 return;
 226         }
 227         enable_irq_wake(gpio_to_irq(gpio_nr));
 228 }
 229
 230 static int __init omap_serial_wakeup_init(void)
 231 {
 232         if (!cpu_is_omap16xx())
 233                 return 0;
 234
 235         if (uart1_ck != NULL)
 236                 omap_serial_set_port_wakeup(37);
 237         if (uart2_ck != NULL)
 238                 omap_serial_set_port_wakeup(18);
 239         if (uart3_ck != NULL)
 240                 omap_serial_set_port_wakeup(49);
 241
 242         return 0;
 243 }
 244 late_initcall(omap_serial_wakeup_init);
 245
 246 #endif  /* CONFIG_OMAP_SERIAL_WAKE */
 247
 248 static int __init omap_init(void)
 249 {
 250         return platform_device_register(&serial_device);
 251 }
 252 arch_initcall(omap_init);