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  1. /*
  2.  * Copyright (c) 2009 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup genarch
  30.  * @{
  31.  */
  32. /**
  33.  * @file
  34.  * @brief NS 16550 serial controller driver.
  35.  */
  36.  
  37. #include <genarch/drivers/ns16550/ns16550.h>
  38. #include <ddi/irq.h>
  39. #include <arch/asm.h>
  40. #include <console/chardev.h>
  41. #include <mm/slab.h>
  42. #include <ddi/device.h>
  43.  
  44. #define LSR_DATA_READY  0x01
  45.  
  46. static indev_operations_t kbrdin_ops = {
  47.     .poll = NULL
  48. };
  49.  
  50. static irq_ownership_t ns16550_claim(irq_t *irq)
  51. {
  52.     ns16550_instance_t *instance = irq->instance;
  53.     ns16550_t *dev = instance->ns16550;
  54.    
  55.     if (pio_read_8(&dev->lsr) & LSR_DATA_READY)
  56.         return IRQ_ACCEPT;
  57.     else
  58.         return IRQ_DECLINE;
  59. }
  60.  
  61. static void ns16550_irq_handler(irq_t *irq)
  62. {
  63.     ns16550_instance_t *instance = irq->instance;
  64.     ns16550_t *dev = instance->ns16550;
  65.    
  66.     if (pio_read_8(&dev->lsr) & LSR_DATA_READY) {
  67.         uint8_t x = pio_read_8(&dev->rbr);
  68.         indev_push_character(&instance->kbrdin, x);
  69.     }
  70. }
  71.  
  72. /** Initialize ns16550.
  73.  *
  74.  * @param dev      Addrress of the beginning of the device in I/O space.
  75.  * @param devno    Device number.
  76.  * @param inr      Interrupt number.
  77.  * @param cir      Clear interrupt function.
  78.  * @param cir_arg  First argument to cir.
  79.  *
  80.  * @return Keyboard device pointer or NULL on failure.
  81.  *
  82.  */
  83. indev_t *ns16550_init(ns16550_t *dev, inr_t inr, cir_t cir, void *cir_arg)
  84. {
  85.     ns16550_instance_t *instance
  86.         = malloc(sizeof(ns16550_instance_t), FRAME_ATOMIC);
  87.     if (!instance)
  88.         return NULL;
  89.    
  90.     indev_initialize("ns16550", &instance->kbrdin, &kbrdin_ops);
  91.    
  92.     instance->ns16550 = dev;
  93.    
  94.     irq_initialize(&instance->irq);
  95.     instance->irq.devno = device_assign_devno();
  96.     instance->irq.inr = inr;
  97.     instance->irq.claim = ns16550_claim;
  98.     instance->irq.handler = ns16550_irq_handler;
  99.     instance->irq.instance = instance;
  100.     instance->irq.cir = cir;
  101.     instance->irq.cir_arg = cir_arg;
  102.     irq_register(&instance->irq);
  103.    
  104.     while ((pio_read_8(&dev->lsr) & LSR_DATA_READY))
  105.         (void) pio_read_8(&dev->rbr);
  106.    
  107.     /* Enable interrupts */
  108.     pio_write_8(&dev->ier, IER_ERBFI);
  109.     pio_write_8(&dev->mcr, MCR_OUT2);
  110.    
  111.     return &instance->kbrdin;
  112. }
  113.  
  114. /** @}
  115.  */
  116.