drivers/staging/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 "cx25821.h"
  24
  25 /********************* GPIO stuffs *********************/
  26 void cx25821_set_gpiopin_direction(struct cx25821_dev *dev,
  27                                    int pin_number, int pin_logic_value)
  28 {
  29         int bit = pin_number;
  30         u32 gpio_oe_reg = GPIO_LO_OE;
  31         u32 gpio_register = 0;
  32         u32 value = 0;
  33
  34         /* Check for valid pinNumber */
  35         if (pin_number >= 47)
  36                 return;
  37
  38         if (pin_number > 31) {
  39                 bit = pin_number - 31;
  40                 gpio_oe_reg = GPIO_HI_OE;
  41         }
  42         /* Here we will make sure that the GPIOs 0 and 1 are output. keep the
  43          * rest as is */
  44         gpio_register = cx_read(gpio_oe_reg);
  45
  46         if (pin_logic_value == 1)
  47                 value = gpio_register | Set_GPIO_Bit(bit);
  48         else
  49                 value = gpio_register & Clear_GPIO_Bit(bit);
  50
  51         cx_write(gpio_oe_reg, value);
  52 }
  53 EXPORT_SYMBOL(cx25821_set_gpiopin_direction);
  54
  55 static void cx25821_set_gpiopin_logicvalue(struct cx25821_dev *dev,
  56                                            int pin_number, int pin_logic_value)
  57 {
  58         int bit = pin_number;
  59         u32 gpio_reg = GPIO_LO;
  60         u32 value = 0;
  61
  62         /* Check for valid pinNumber */
  63         if (pin_number >= 47)
  64                 return;
  65
  66         /* change to output direction */
  67         cx25821_set_gpiopin_direction(dev, pin_number, 0);
  68
  69         if (pin_number > 31) {
  70                 bit = pin_number - 31;
  71                 gpio_reg = GPIO_HI;
  72         }
  73
  74         value = cx_read(gpio_reg);
  75
  76         if (pin_logic_value == 0)
  77                 value &= Clear_GPIO_Bit(bit);
  78         else
  79                 value |= Set_GPIO_Bit(bit);
  80
  81         cx_write(gpio_reg, value);
  82 }
  83
  84 void cx25821_gpio_init(struct cx25821_dev *dev)
  85 {
  86         if (dev == NULL)
  87                 return;
  88
  89         switch (dev->board) {
  90         case CX25821_BOARD_CONEXANT_ATHENA10:
  91         default:
  92                 /* set GPIO 5 to select the path for Medusa/Athena */
  93                 cx25821_set_gpiopin_logicvalue(dev, 5, 1);
  94                 mdelay(20);
  95                 break;
  96         }
  97
  98 }