arch/arm/plat-mxc/iomux-v3.c

   1 /*
   2  * Copyright 2004-2006 Freescale Semiconductor, Inc. All Rights Reserved.
   3  * Copyright (C) 2008 by Sascha Hauer <kernel@pengutronix.de>
   4  * Copyright (C) 2009 by Jan Weitzel Phytec Messtechnik GmbH,
   5  *                       <armlinux@phytec.de>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  19  * MA 02110-1301, USA.
  20  */
  21 #include <linux/errno.h>
  22 #include <linux/init.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/string.h>
  26 #include <linux/gpio.h>
  27
  28 #include <mach/hardware.h>
  29 #include <asm/mach/map.h>
  30 #include <mach/iomux-v3.h>
  31
  32 #define IOMUX_BASE      IO_ADDRESS(IOMUXC_BASE_ADDR)
  33
  34 static unsigned long iomux_v3_pad_alloc_map[0x200 / BITS_PER_LONG];
  35
  36 /*
  37  * setups a single pin:
  38  *      - reserves the pin so that it is not claimed by another driver
  39  *      - setups the iomux according to the configuration
  40  */
  41 int mxc_iomux_v3_setup_pad(struct pad_desc *pad)
  42 {
  43         unsigned int pad_ofs = pad->pad_ctrl_ofs;
  44
  45         if (test_and_set_bit(pad_ofs >> 2, iomux_v3_pad_alloc_map))
  46                 return -EBUSY;
  47         if (pad->mux_ctrl_ofs)
  48                 __raw_writel(pad->mux_mode, IOMUX_BASE + pad->mux_ctrl_ofs);
  49
  50         if (pad->select_input_ofs)
  51                 __raw_writel(pad->select_input,
  52                                 IOMUX_BASE + pad->select_input_ofs);
  53
  54         if (!(pad->pad_ctrl & NO_PAD_CTRL))
  55                 __raw_writel(pad->pad_ctrl, IOMUX_BASE + pad->pad_ctrl_ofs);
  56         return 0;
  57 }
  58 EXPORT_SYMBOL(mxc_iomux_v3_setup_pad);
  59
  60 int mxc_iomux_v3_setup_multiple_pads(struct pad_desc *pad_list, unsigned count)
  61 {
  62         struct pad_desc *p = pad_list;
  63         int i;
  64         int ret;
  65
  66         for (i = 0; i < count; i++) {
  67                 ret = mxc_iomux_v3_setup_pad(p);
  68                 if (ret)
  69                         goto setup_error;
  70                 p++;
  71         }
  72         return 0;
  73
  74 setup_error:
  75         mxc_iomux_v3_release_multiple_pads(pad_list, i);
  76         return ret;
  77 }
  78 EXPORT_SYMBOL(mxc_iomux_v3_setup_multiple_pads);
  79
  80 void mxc_iomux_v3_release_pad(struct pad_desc *pad)
  81 {
  82         unsigned int pad_ofs = pad->pad_ctrl_ofs;
  83
  84         clear_bit(pad_ofs >> 2, iomux_v3_pad_alloc_map);
  85 }
  86 EXPORT_SYMBOL(mxc_iomux_v3_release_pad);
  87
  88 void mxc_iomux_v3_release_multiple_pads(struct pad_desc *pad_list, int count)
  89 {
  90         struct pad_desc *p = pad_list;
  91         int i;
  92
  93         for (i = 0; i < count; i++) {
  94                 mxc_iomux_v3_release_pad(p);
  95                 p++;
  96         }
  97 }
  98 EXPORT_SYMBOL(mxc_iomux_v3_release_multiple_pads);