arch/arm/plat-stmp3xxx/include/mach/pinmux.h

   1 /*
   2  * Freescale STMP37XX/STMP378X Pin Multiplexing
   3  *
   4  * Author: Vladislav Buzov <vbuzov@embeddedalley.com>
   5  *
   6  * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
   7  * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
   8  */
   9
  10 /*
  11  * The code contained herein is licensed under the GNU General Public
  12  * License. You may obtain a copy of the GNU General Public License
  13  * Version 2 or later at the following locations:
  14  *
  15  * http://www.opensource.org/licenses/gpl-license.html
  16  * http://www.gnu.org/copyleft/gpl.html
  17  */
  18 #ifndef __PINMUX_H
  19 #define __PINMUX_H
  20
  21 #include <linux/spinlock.h>
  22 #include <linux/types.h>
  23 #include <linux/gpio.h>
  24 #include <asm-generic/gpio.h>
  25
  26 /* Pin definitions */
  27 #include "pins.h"
  28 #include <mach/pins.h>
  29
  30 /*
  31  * Each pin may be routed up to four different HW interfaces
  32  * including GPIO
  33  */
  34 enum pin_fun {
  35         PIN_FUN1 = 0,
  36         PIN_FUN2,
  37         PIN_FUN3,
  38         PIN_GPIO,
  39 };
  40
  41 /*
  42  * Each pin may have different output drive strength in range from
  43  * 4mA to 20mA. The most common case is 4, 8 and 12 mA strengths.
  44  */
  45 enum pin_strength {
  46         PIN_4MA = 0,
  47         PIN_8MA,
  48         PIN_12MA,
  49         PIN_16MA,
  50         PIN_20MA,
  51 };
  52
  53 /*
  54  * Each pin can be programmed for 1.8V or 3.3V
  55  */
  56 enum pin_voltage {
  57         PIN_1_8V = 0,
  58         PIN_3_3V,
  59 };
  60
  61 /*
  62  * Structure to define a group of pins and their parameters
  63  */
  64 struct pin_desc {
  65         unsigned id;
  66         enum pin_fun fun;
  67         enum pin_strength strength;
  68         enum pin_voltage voltage;
  69         unsigned pullup:1;
  70 };
  71
  72 struct pin_group {
  73         struct pin_desc *pins;
  74         int nr_pins;
  75 };
  76
  77 /* Set pin drive strength */
  78 void stmp3xxx_pin_strength(unsigned id, enum pin_strength strength,
  79                            const char *label);
  80
  81 /* Set pin voltage */
  82 void stmp3xxx_pin_voltage(unsigned id, enum pin_voltage voltage,
  83                            const char *label);
  84
  85 /* Enable pull-up resistor for a pin */
  86 void stmp3xxx_pin_pullup(unsigned id, int enable, const char *label);
  87
  88 /*
  89  * Request a pin ownership, only one module (identified by @label)
  90  * may own a pin.
  91  */
  92 int stmp3xxx_request_pin(unsigned id, enum pin_fun fun, const char *label);
  93
  94 /* Release pin */
  95 void stmp3xxx_release_pin(unsigned id, const char *label);
  96
  97 void stmp3xxx_set_pin_type(unsigned id, enum pin_fun fun);
  98
  99 /*
 100  * Each bank is associated with a number of registers to control
 101  * pin function, drive strength, voltage and pull-up reigster. The
 102  * number of registers of a given type depends on the number of bits
 103  * describin particular pin.
 104  */
 105 #define HW_MUXSEL_NUM           2       /* registers per bank */
 106 #define HW_MUXSEL_PIN_LEN       2       /* bits per pin */
 107 #define HW_MUXSEL_PIN_NUM       16      /* pins per register */
 108 #define HW_MUXSEL_PINFUN_MASK   0x3     /* pin function mask */
 109 #define HW_MUXSEL_PINFUN_NUM    4       /* four options for a pin */
 110
 111 #define HW_DRIVE_NUM            4       /* registers per bank */
 112 #define HW_DRIVE_PIN_LEN        4       /* bits per pin */
 113 #define HW_DRIVE_PIN_NUM        8       /* pins per register */
 114 #define HW_DRIVE_PINDRV_MASK    0x3     /* pin strength mask - 2 bits */
 115 #define HW_DRIVE_PINDRV_NUM     5       /* five possible strength values */
 116 #define HW_DRIVE_PINV_MASK      0x4     /* pin voltage mask - 1 bit */
 117
 118
 119 struct stmp3xxx_pinmux_bank {
 120         struct gpio_chip chip;
 121
 122         /* Pins allocation map */
 123         unsigned long pin_map;
 124
 125         /* Pin owner names */
 126         const char *pin_labels[32];
 127
 128         /* Bank registers */
 129         void __iomem *hw_muxsel[HW_MUXSEL_NUM];
 130         void __iomem *hw_drive[HW_DRIVE_NUM];
 131         void __iomem *hw_pull;
 132
 133         void __iomem *pin2irq,
 134                 *irqlevel,
 135                 *irqpolarity,
 136                 *irqen,
 137                 *irqstat;
 138
 139         /* HW MUXSEL register function bit values */
 140         u8 functions[HW_MUXSEL_PINFUN_NUM];
 141
 142         /*
 143          * HW DRIVE register strength bit values:
 144          * 0xff - requested strength is not supported for this bank
 145          */
 146         u8 strengths[HW_DRIVE_PINDRV_NUM];
 147
 148         /* GPIO things */
 149         void __iomem *hw_gpio_in,
 150                      *hw_gpio_out,
 151                      *hw_gpio_doe;
 152         int irq, virq;
 153 };
 154
 155 int __init stmp3xxx_pinmux_init(int virtual_irq_start);
 156
 157 #endif /* __PINMUX_H */