1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * First generation of pinmux driver for Amlogic Meson SoCs 4 * 5 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> 6 * Copyright (C) 2017 Jerome Brunet <jbrunet@baylibre.com> 7 */ 8 9 /* For this first generation of pinctrl driver every pinmux group can be 10 * enabled by a specific bit in the first register range. When all groups for 11 * a given pin are disabled the pin acts as a GPIO. 12 */ 13 #include <linux/device.h> 14 #include <linux/regmap.h> 15 #include <linux/pinctrl/pinctrl.h> 16 #include <linux/pinctrl/pinmux.h> 17 18 #include "pinctrl-meson.h" 19 #include "pinctrl-meson8-pmx.h" 20 21 /** 22 * meson8_pmx_disable_other_groups() - disable other groups using a given pin 23 * 24 * @pc: meson pin controller device 25 * @pin: number of the pin 26 * @sel_group: index of the selected group, or -1 if none 27 * 28 * The function disables all pinmux groups using a pin except the 29 * selected one. If @sel_group is -1 all groups are disabled, leaving 30 * the pin in GPIO mode. 31 */ 32 static void meson8_pmx_disable_other_groups(struct meson_pinctrl *pc, 33 unsigned int pin, int sel_group) 34 { 35 struct meson_pmx_group *group; 36 struct meson8_pmx_data *pmx_data; 37 int i, j; 38 39 for (i = 0; i < pc->data->num_groups; i++) { 40 group = &pc->data->groups[i]; 41 pmx_data = (struct meson8_pmx_data *)group->data; 42 if (pmx_data->is_gpio || i == sel_group) 43 continue; 44 45 for (j = 0; j < group->num_pins; j++) { 46 if (group->pins[j] == pin) { 47 /* We have found a group using the pin */ 48 regmap_update_bits(pc->reg_mux, 49 pmx_data->reg * 4, 50 BIT(pmx_data->bit), 0); 51 } 52 } 53 } 54 } 55 56 static int meson8_pmx_set_mux(struct pinctrl_dev *pcdev, unsigned func_num, 57 unsigned group_num) 58 { 59 struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); 60 struct meson_pmx_func *func = &pc->data->funcs[func_num]; 61 struct meson_pmx_group *group = &pc->data->groups[group_num]; 62 struct meson8_pmx_data *pmx_data = 63 (struct meson8_pmx_data *)group->data; 64 int i, ret = 0; 65 66 dev_dbg(pc->dev, "enable function %s, group %s\n", func->name, 67 group->name); 68 69 /* 70 * Disable groups using the same pin. 71 * The selected group is not disabled to avoid glitches. 72 */ 73 for (i = 0; i < group->num_pins; i++) 74 meson8_pmx_disable_other_groups(pc, group->pins[i], group_num); 75 76 /* Function 0 (GPIO) doesn't need any additional setting */ 77 if (func_num) 78 ret = regmap_update_bits(pc->reg_mux, pmx_data->reg * 4, 79 BIT(pmx_data->bit), 80 BIT(pmx_data->bit)); 81 82 return ret; 83 } 84 85 static int meson8_pmx_request_gpio(struct pinctrl_dev *pcdev, 86 struct pinctrl_gpio_range *range, 87 unsigned offset) 88 { 89 struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev); 90 91 meson8_pmx_disable_other_groups(pc, offset, -1); 92 93 return 0; 94 } 95 96 const struct pinmux_ops meson8_pmx_ops = { 97 .set_mux = meson8_pmx_set_mux, 98 .get_functions_count = meson_pmx_get_funcs_count, 99 .get_function_name = meson_pmx_get_func_name, 100 .get_function_groups = meson_pmx_get_groups, 101 .gpio_request_enable = meson8_pmx_request_gpio, 102 }; 103 EXPORT_SYMBOL_GPL(meson8_pmx_ops); 104 MODULE_LICENSE("GPL v2"); 105