LXR uboot/arch/arm/mach-davinci/pinmux.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * DaVinci pinmux functions.
   4 *
   5 * Copyright (C) 2009 Nick Thompson, GE Fanuc Ltd, <nick.thompson@gefanuc.com>
   6 * Copyright (C) 2007 Sergey Kubushyn <ksi@koi8.net>
   7 * Copyright (C) 2008 Lyrtech <www.lyrtech.com>
   8 * Copyright (C) 2004 Texas Instruments.
   9 */
  10
  11#include <common.h>
  12#include <asm/arch/hardware.h>
  13#include <asm/io.h>
  14#include <asm/arch/davinci_misc.h>
  15
  16/*
  17 * Change the setting of a pin multiplexer field.
  18 *
  19 * Takes an array of pinmux settings similar to:
  20 *
  21 * struct pinmux_config uart_pins[] = {
  22 *      { &davinci_syscfg_regs->pinmux[8], 2, 7 },
  23 *      { &davinci_syscfg_regs->pinmux[9], 2, 0 }
  24 * };
  25 *
  26 * Stepping through the array, each pinmux[n] register has the given value
  27 * set in the pin mux field specified.
  28 *
  29 * The number of pins in the array must be passed (ARRAY_SIZE can provide
  30 * this value conveniently).
  31 *
  32 * Returns 0 if all field numbers and values are in the correct range,
  33 * else returns -1.
  34 */
  35int davinci_configure_pin_mux(const struct pinmux_config *pins,
  36                              const int n_pins)
  37{
  38        int i;
  39
  40        /* check for invalid pinmux values */
  41        for (i = 0; i < n_pins; i++) {
  42                if (pins[i].field >= PIN_MUX_NUM_FIELDS ||
  43                    (pins[i].value & ~PIN_MUX_FIELD_MASK) != 0)
  44                        return -1;
  45        }
  46
  47        /* configure the pinmuxes */
  48        for (i = 0; i < n_pins; i++) {
  49                const int offset = pins[i].field * PIN_MUX_FIELD_SIZE;
  50                const unsigned int value = pins[i].value << offset;
  51                const unsigned int mask = PIN_MUX_FIELD_MASK << offset;
  52                const dv_reg *mux = pins[i].mux;
  53
  54                writel(value | (readl(mux) & (~mask)), mux);
  55        }
  56
  57        return 0;
  58}
  59
  60/*
  61 * Configure multiple pinmux resources.
  62 *
  63 * Takes an pinmux_resource array of pinmux_config and pin counts:
  64 *
  65 * const struct pinmux_resource pinmuxes[] = {
  66 *      PINMUX_ITEM(uart_pins),
  67 *      PINMUX_ITEM(i2c_pins),
  68 * };
  69 *
  70 * The number of items in the array must be passed (ARRAY_SIZE can provide
  71 * this value conveniently).
  72 *
  73 * Each item entry is configured in the defined order. If configuration
  74 * of any item fails, -1 is returned and none of the following items are
  75 * configured. On success, 0 is returned.
  76 */
  77int davinci_configure_pin_mux_items(const struct pinmux_resource *item,
  78                                    const int n_items)
  79{
  80        int i;
  81
  82        for (i = 0; i < n_items; i++) {
  83                if (davinci_configure_pin_mux(item[i].pins,
  84                                              item[i].n_pins) != 0)
  85                        return -1;
  86        }
  87
  88        return 0;
  89}
  90