drivers/staging/solo6x10/gpio.c

   1 /*
   2  * Copyright (C) 2010 Bluecherry, LLC www.bluecherrydvr.com
   3  * Copyright (C) 2010 Ben Collins <bcollins@bluecherry.net>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/fs.h>
  22 #include <asm/uaccess.h>
  23 #include "solo6x10.h"
  24
  25 static void solo_gpio_mode(struct solo_dev *solo_dev,
  26                            unsigned int port_mask, unsigned int mode)
  27 {
  28         int port;
  29         unsigned int ret;
  30
  31         ret = solo_reg_read(solo_dev, SOLO_GPIO_CONFIG_0);
  32
  33         /* To set gpio */
  34         for (port = 0; port < 16; port++) {
  35                 if (!((1 << port) & port_mask))
  36                         continue;
  37
  38                 ret &= (~(3 << (port << 1)));
  39                 ret |= ((mode & 3) << (port << 1));
  40         }
  41
  42         solo_reg_write(solo_dev, SOLO_GPIO_CONFIG_0, ret);
  43
  44         /* To set extended gpio - sensor */
  45         ret = solo_reg_read(solo_dev, SOLO_GPIO_CONFIG_1);
  46
  47         for (port = 0; port < 16; port++) {
  48                 if (!((1 << (port + 16)) & port_mask))
  49                         continue;
  50
  51                 if (!mode)
  52                         ret &= ~(1 << port);
  53                 else
  54                         ret |= 1 << port;
  55         }
  56
  57         solo_reg_write(solo_dev, SOLO_GPIO_CONFIG_1, ret);
  58 }
  59
  60 static void solo_gpio_set(struct solo_dev *solo_dev, unsigned int value)
  61 {
  62         solo_reg_write(solo_dev, SOLO_GPIO_DATA_OUT,
  63                        solo_reg_read(solo_dev, SOLO_GPIO_DATA_OUT) | value);
  64 }
  65
  66 static void solo_gpio_clear(struct solo_dev *solo_dev, unsigned int value)
  67 {
  68         solo_reg_write(solo_dev, SOLO_GPIO_DATA_OUT,
  69                        solo_reg_read(solo_dev, SOLO_GPIO_DATA_OUT) & ~value);
  70 }
  71
  72 static void solo_gpio_config(struct solo_dev *solo_dev)
  73 {
  74         /* Video reset */
  75         solo_gpio_mode(solo_dev, 0x30, 1);
  76         solo_gpio_clear(solo_dev, 0x30);
  77         udelay(100);
  78         solo_gpio_set(solo_dev, 0x30);
  79         udelay(100);
  80
  81         /* Warning: Don't touch the next line unless you're sure of what
  82          * you're doing: first four gpio [0-3] are used for video. */
  83         solo_gpio_mode(solo_dev, 0x0f, 2);
  84
  85         /* We use bit 8-15 of SOLO_GPIO_CONFIG_0 for relay purposes */
  86         solo_gpio_mode(solo_dev, 0xff00, 1);
  87
  88         /* Initially set relay status to 0 */
  89         solo_gpio_clear(solo_dev, 0xff00);
  90 }
  91
  92 int solo_gpio_init(struct solo_dev *solo_dev)
  93 {
  94         solo_gpio_config(solo_dev);
  95         return 0;
  96 }
  97
  98 void solo_gpio_exit(struct solo_dev *solo_dev)
  99 {
 100         solo_gpio_clear(solo_dev, 0x30);
 101         solo_gpio_config(solo_dev);
 102 }