LXR linux/drivers/pinctrl/meson/pinctrl-meson-axg-pmx.c

   1/*
   2 * Second generation of pinmux driver for Amlogic Meson-AXG SoC.
   3 *
   4 * Copyright (c) 2017 Baylibre SAS.
   5 * Author:  Jerome Brunet  <jbrunet@baylibre.com>
   6 *
   7 * Copyright (c) 2017 Amlogic, Inc. All rights reserved.
   8 * Author: Xingyu Chen <xingyu.chen@amlogic.com>
   9 *
  10 * SPDX-License-Identifier: (GPL-2.0+ or MIT)
  11 */
  12
  13/*
  14 * This new generation of pinctrl IP is mainly adopted by the
  15 * Meson-AXG SoC and later series, which use 4-width continuous
  16 * register bit to select the function for each pin.
  17 *
  18 * The value 0 is always selecting the GPIO mode, while other
  19 * values (start from 1) for selecting the function mode.
  20 */
  21#include <linux/device.h>
  22#include <linux/regmap.h>
  23#include <linux/pinctrl/pinctrl.h>
  24#include <linux/pinctrl/pinmux.h>
  25
  26#include "pinctrl-meson.h"
  27#include "pinctrl-meson-axg-pmx.h"
  28
  29static int meson_axg_pmx_get_bank(struct meson_pinctrl *pc,
  30                        unsigned int pin,
  31                        struct meson_pmx_bank **bank)
  32{
  33        int i;
  34        struct meson_axg_pmx_data *pmx = pc->data->pmx_data;
  35
  36        for (i = 0; i < pmx->num_pmx_banks; i++)
  37                if (pin >= pmx->pmx_banks[i].first &&
  38                                pin <= pmx->pmx_banks[i].last) {
  39                        *bank = &pmx->pmx_banks[i];
  40                        return 0;
  41                }
  42
  43        return -EINVAL;
  44}
  45
  46static int meson_pmx_calc_reg_and_offset(struct meson_pmx_bank *bank,
  47                        unsigned int pin, unsigned int *reg,
  48                        unsigned int *offset)
  49{
  50        int shift;
  51
  52        shift = pin - bank->first;
  53
  54        *reg = bank->reg + (bank->offset + (shift << 2)) / 32;
  55        *offset = (bank->offset + (shift << 2)) % 32;
  56
  57        return 0;
  58}
  59
  60static int meson_axg_pmx_update_function(struct meson_pinctrl *pc,
  61                        unsigned int pin, unsigned int func)
  62{
  63        int ret;
  64        int reg;
  65        int offset;
  66        struct meson_pmx_bank *bank;
  67
  68        ret = meson_axg_pmx_get_bank(pc, pin, &bank);
  69        if (ret)
  70                return ret;
  71
  72        meson_pmx_calc_reg_and_offset(bank, pin, &reg, &offset);
  73
  74        ret = regmap_update_bits(pc->reg_mux, reg << 2,
  75                0xf << offset, (func & 0xf) << offset);
  76
  77        return ret;
  78}
  79
  80static int meson_axg_pmx_set_mux(struct pinctrl_dev *pcdev,
  81                        unsigned int func_num, unsigned int group_num)
  82{
  83        int i;
  84        int ret;
  85        struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
  86        struct meson_pmx_func *func = &pc->data->funcs[func_num];
  87        struct meson_pmx_group *group = &pc->data->groups[group_num];
  88        struct meson_pmx_axg_data *pmx_data =
  89                (struct meson_pmx_axg_data *)group->data;
  90
  91        dev_dbg(pc->dev, "enable function %s, group %s\n", func->name,
  92                group->name);
  93
  94        for (i = 0; i < group->num_pins; i++) {
  95                ret = meson_axg_pmx_update_function(pc, group->pins[i],
  96                        pmx_data->func);
  97                if (ret)
  98                        return ret;
  99        }
 100
 101        return 0;
 102}
 103
 104static int meson_axg_pmx_request_gpio(struct pinctrl_dev *pcdev,
 105                        struct pinctrl_gpio_range *range, unsigned int offset)
 106{
 107        struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
 108
 109        return meson_axg_pmx_update_function(pc, offset, 0);
 110}
 111
 112const struct pinmux_ops meson_axg_pmx_ops = {
 113        .set_mux = meson_axg_pmx_set_mux,
 114        .get_functions_count = meson_pmx_get_funcs_count,
 115        .get_function_name = meson_pmx_get_func_name,
 116        .get_function_groups = meson_pmx_get_groups,
 117        .gpio_request_enable = meson_axg_pmx_request_gpio,
 118};
 119EXPORT_SYMBOL_GPL(meson_axg_pmx_ops);
 120
 121MODULE_LICENSE("Dual BSD/GPL");
 122