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(map: pc->reg_mux, |
49 | reg: pmx_data->reg * 4, |
50 | BIT(pmx_data->bit), val: 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(pctldev: 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, pin: group->pins[i], sel_group: group_num); |
75 | |
76 | /* Function 0 (GPIO) doesn't need any additional setting */ |
77 | if (func_num) |
78 | ret = regmap_update_bits(map: pc->reg_mux, reg: 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(pctldev: pcdev); |
90 | |
91 | meson8_pmx_disable_other_groups(pc, pin: offset, sel_group: -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 | |