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  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #include <linux/module.h>
  24 #include "cx25821.h"
  25
  26 /********************* GPIO stuffs *********************/
  27 void cx25821_set_gpiopin_direction(struct cx25821_dev *dev,
  28                                    int pin_number, int pin_logic_value)
  29 {
  30         int bit = pin_number;
  31         u32 gpio_oe_reg = GPIO_LO_OE;
  32         u32 gpio_register = 0;
  33         u32 value = 0;
  34
  35         /* Check for valid pinNumber */
  36         if (pin_number >= 47)
  37                 return;
  38
  39         if (pin_number > 31) {
  40                 bit = pin_number - 31;
  41                 gpio_oe_reg = GPIO_HI_OE;
  42         }
  43         /* Here we will make sure that the GPIOs 0 and 1 are output. keep the
  44          * rest as is */
  45         gpio_register = cx_read(gpio_oe_reg);
  46
  47         if (pin_logic_value == 1)
  48                 value = gpio_register | Set_GPIO_Bit(bit);
  49         else
  50                 value = gpio_register & Clear_GPIO_Bit(bit);
  51
  52         cx_write(gpio_oe_reg, value);
  53 }
  54 EXPORT_SYMBOL(cx25821_set_gpiopin_direction);
  55
  56 static void cx25821_set_gpiopin_logicvalue(struct cx25821_dev *dev,
  57                                            int pin_number, int pin_logic_value)
  58 {
  59         int bit = pin_number;
  60         u32 gpio_reg = GPIO_LO;
  61         u32 value = 0;
  62
  63         /* Check for valid pinNumber */
  64         if (pin_number >= 47)
  65                 return;
  66
  67         /* change to output direction */
  68         cx25821_set_gpiopin_direction(dev, pin_number, 0);
  69
  70         if (pin_number > 31) {
  71                 bit = pin_number - 31;
  72                 gpio_reg = GPIO_HI;
  73         }
  74
  75         value = cx_read(gpio_reg);
  76
  77         if (pin_logic_value == 0)
  78                 value &= Clear_GPIO_Bit(bit);
  79         else
  80                 value |= Set_GPIO_Bit(bit);
  81
  82         cx_write(gpio_reg, value);
  83 }
  84
  85 void cx25821_gpio_init(struct cx25821_dev *dev)
  86 {
  87         if (dev == NULL)
  88                 return;
  89
  90         switch (dev->board) {
  91         case CX25821_BOARD_CONEXANT_ATHENA10:
  92         default:
  93                 /* set GPIO 5 to select the path for Medusa/Athena */
  94                 cx25821_set_gpiopin_logicvalue(dev, 5, 1);
  95                 mdelay(20);
  96                 break;
  97         }
  98
  99 }