pinctrl-meson-axg-pmx.c

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