drivers/media/pci/cx25821/cx25821-gpio.c

   1 /*
   2  *  Driver for the Conexant CX25821 PCIe bridge
   3  *
   4  *  Copyright (C) 2009 Conexant Systems Inc.
   5  *  Authors  <shu.lin@conexant.com>, <hiep.huynh@conexant.com>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *
  16  *  GNU General Public License for more details.
  17  */
  18
  19 #include <linux/module.h>
  20 #include "cx25821.h"
  21
  22 /********************* GPIO stuffs *********************/
  23 void cx25821_set_gpiopin_direction(struct cx25821_dev *dev,
  24                                    int pin_number, int pin_logic_value)
  25 {
  26         int bit = pin_number;
  27         u32 gpio_oe_reg = GPIO_LO_OE;
  28         u32 gpio_register = 0;
  29         u32 value = 0;
  30
  31         /* Check for valid pinNumber */
  32         if (pin_number >= 47)
  33                 return;
  34
  35         if (pin_number > 31) {
  36                 bit = pin_number - 31;
  37                 gpio_oe_reg = GPIO_HI_OE;
  38         }
  39         /* Here we will make sure that the GPIOs 0 and 1 are output. keep the
  40          * rest as is */
  41         gpio_register = cx_read(gpio_oe_reg);
  42
  43         if (pin_logic_value == 1)
  44                 value = gpio_register | Set_GPIO_Bit(bit);
  45         else
  46                 value = gpio_register & Clear_GPIO_Bit(bit);
  47
  48         cx_write(gpio_oe_reg, value);
  49 }
  50 EXPORT_SYMBOL(cx25821_set_gpiopin_direction);
  51
  52 static void cx25821_set_gpiopin_logicvalue(struct cx25821_dev *dev,
  53                                            int pin_number, int pin_logic_value)
  54 {
  55         int bit = pin_number;
  56         u32 gpio_reg = GPIO_LO;
  57         u32 value = 0;
  58
  59         /* Check for valid pinNumber */
  60         if (pin_number >= 47)
  61                 return;
  62
  63         /* change to output direction */
  64         cx25821_set_gpiopin_direction(dev, pin_number, 0);
  65
  66         if (pin_number > 31) {
  67                 bit = pin_number - 31;
  68                 gpio_reg = GPIO_HI;
  69         }
  70
  71         value = cx_read(gpio_reg);
  72
  73         if (pin_logic_value == 0)
  74                 value &= Clear_GPIO_Bit(bit);
  75         else
  76                 value |= Set_GPIO_Bit(bit);
  77
  78         cx_write(gpio_reg, value);
  79 }
  80
  81 void cx25821_gpio_init(struct cx25821_dev *dev)
  82 {
  83         if (dev == NULL)
  84                 return;
  85
  86         switch (dev->board) {
  87         case CX25821_BOARD_CONEXANT_ATHENA10:
  88         default:
  89                 /* set GPIO 5 to select the path for Medusa/Athena */
  90                 cx25821_set_gpiopin_logicvalue(dev, 5, 1);
  91                 msleep(20);
  92                 break;
  93         }
  94
  95 }