1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
4 * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
5 */
6
7 #include <dm.h>
8 #include <dm/pinctrl.h>
9 #include <dt-bindings/pinctrl/sandbox-pinmux.h>
10 #include <log.h>
11 #include <linux/bitops.h>
12
13 /*
14 * This driver emulates a pin controller with the following rules:
15 * - The pinctrl config for each pin must be set individually
16 * - The first three pins (P0-P2) must be muxed as a group
17 * - The next two pins (P3-P4) must be muxed as a group
18 * - The last four pins (P5-P8) must be muxed individually
19 */
20
21 static const char * const sandbox_pins[] = {
22 #define PIN(x) \
23 [x] = "P" #x
24 PIN(0),
25 PIN(1),
26 PIN(2),
27 PIN(3),
28 PIN(4),
29 PIN(5),
30 PIN(6),
31 PIN(7),
32 PIN(8),
33 #undef PIN
34 };
35
36 static const char * const sandbox_pins_muxing[][2] = {
37 { "UART TX", "I2C SCL" },
38 { "UART RX", "I2C SDA" },
39 { "SPI SCLK", "I2S SCK" },
40 { "SPI MOSI", "I2S SD" },
41 { "SPI MISO", "I2S WS" },
42 { "GPIO0", "SPI CS0" },
43 { "GPIO1", "SPI CS1" },
44 { "GPIO2", "PWM0" },
45 { "GPIO3", "ONEWIRE" },
46 };
47
48 #define SANDBOX_GROUP_I2C_UART 0
49 #define SANDBOX_GROUP_SPI_I2S 1
50
51 static const char * const sandbox_groups[] = {
52 [SANDBOX_GROUP_I2C_UART] = "I2C_UART",
53 [SANDBOX_GROUP_SPI_I2S] = "SPI_I2S",
54 };
55
56 static const char * const sandbox_functions[] = {
57 #define FUNC(id) \
58 [SANDBOX_PINMUX_##id] = #id
59 FUNC(UART),
60 FUNC(I2C),
61 FUNC(SPI),
62 FUNC(I2S),
63 FUNC(GPIO),
64 FUNC(CS),
65 FUNC(PWM),
66 FUNC(ONEWIRE),
67 #undef FUNC
68 };
69
70 static const struct pinconf_param sandbox_conf_params[] = {
71 { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
72 { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 },
73 { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 },
74 { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 },
75 { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 },
76 { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 },
77 { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 },
78 { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 },
79 { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 },
80 { "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 },
81 { "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 },
82 };
83
84 /* Bitfield used to save param and value of each pin/selector */
85 struct sandbox_pinctrl_priv {
86 unsigned int mux;
87 unsigned int pins_param[ARRAY_SIZE(sandbox_pins)];
88 unsigned int pins_value[ARRAY_SIZE(sandbox_pins)];
89 };
90
sandbox_get_pins_count(struct udevice * dev)91 static int sandbox_get_pins_count(struct udevice *dev)
92 {
93 return ARRAY_SIZE(sandbox_pins);
94 }
95
sandbox_get_pin_name(struct udevice * dev,unsigned selector)96 static const char *sandbox_get_pin_name(struct udevice *dev, unsigned selector)
97 {
98 return sandbox_pins[selector];
99 }
100
sandbox_get_pin_muxing(struct udevice * dev,unsigned int selector,char * buf,int size)101 static int sandbox_get_pin_muxing(struct udevice *dev,
102 unsigned int selector,
103 char *buf, int size)
104 {
105 const struct pinconf_param *p;
106 struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
107 int i;
108
109 snprintf(buf, size, "%s",
110 sandbox_pins_muxing[selector][!!(priv->mux & BIT(selector))]);
111
112 if (priv->pins_param[selector]) {
113 for (i = 0, p = sandbox_conf_params;
114 i < ARRAY_SIZE(sandbox_conf_params);
115 i++, p++) {
116 if ((priv->pins_param[selector] & BIT(p->param)) &&
117 (!!(priv->pins_value[selector] & BIT(p->param)) ==
118 p->default_value)) {
119 strncat(buf, " ", size);
120 strncat(buf, p->property, size);
121 }
122 }
123 }
124 strncat(buf, ".", size);
125
126 return 0;
127 }
128
sandbox_get_groups_count(struct udevice * dev)129 static int sandbox_get_groups_count(struct udevice *dev)
130 {
131 return ARRAY_SIZE(sandbox_groups);
132 }
133
sandbox_get_group_name(struct udevice * dev,unsigned selector)134 static const char *sandbox_get_group_name(struct udevice *dev,
135 unsigned selector)
136 {
137 return sandbox_groups[selector];
138 }
139
sandbox_get_functions_count(struct udevice * dev)140 static int sandbox_get_functions_count(struct udevice *dev)
141 {
142 return ARRAY_SIZE(sandbox_functions);
143 }
144
sandbox_get_function_name(struct udevice * dev,unsigned selector)145 static const char *sandbox_get_function_name(struct udevice *dev,
146 unsigned selector)
147 {
148 return sandbox_functions[selector];
149 }
150
sandbox_pinmux_set(struct udevice * dev,unsigned pin_selector,unsigned func_selector)151 static int sandbox_pinmux_set(struct udevice *dev, unsigned pin_selector,
152 unsigned func_selector)
153 {
154 int mux;
155 struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
156
157 debug("sandbox pinmux: pin = %d (%s), function = %d (%s)\n",
158 pin_selector, sandbox_get_pin_name(dev, pin_selector),
159 func_selector, sandbox_get_function_name(dev, func_selector));
160
161 if (pin_selector < 5)
162 return -EINVAL;
163
164 switch (func_selector) {
165 case SANDBOX_PINMUX_GPIO:
166 mux = 0;
167 break;
168 case SANDBOX_PINMUX_CS:
169 case SANDBOX_PINMUX_PWM:
170 case SANDBOX_PINMUX_ONEWIRE:
171 mux = BIT(pin_selector);
172 break;
173 default:
174 return -EINVAL;
175 }
176
177 priv->mux &= ~BIT(pin_selector);
178 priv->mux |= mux;
179 priv->pins_param[pin_selector] = 0;
180 priv->pins_value[pin_selector] = 0;
181
182 return 0;
183 }
184
sandbox_pinmux_group_set(struct udevice * dev,unsigned group_selector,unsigned func_selector)185 static int sandbox_pinmux_group_set(struct udevice *dev,
186 unsigned group_selector,
187 unsigned func_selector)
188 {
189 bool mux;
190 int i, group_start, group_end;
191 struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
192 unsigned int mask;
193
194 debug("sandbox pinmux: group = %d (%s), function = %d (%s)\n",
195 group_selector, sandbox_get_group_name(dev, group_selector),
196 func_selector, sandbox_get_function_name(dev, func_selector));
197
198 if (group_selector == SANDBOX_GROUP_I2C_UART) {
199 group_start = 0;
200 group_end = 1;
201
202 if (func_selector == SANDBOX_PINMUX_UART)
203 mux = false;
204 else if (func_selector == SANDBOX_PINMUX_I2C)
205 mux = true;
206 else
207 return -EINVAL;
208 } else if (group_selector == SANDBOX_GROUP_SPI_I2S) {
209 group_start = 2;
210 group_end = 4;
211
212 if (func_selector == SANDBOX_PINMUX_SPI)
213 mux = false;
214 else if (func_selector == SANDBOX_PINMUX_I2S)
215 mux = true;
216 else
217 return -EINVAL;
218 } else {
219 return -EINVAL;
220 }
221
222 mask = GENMASK(group_end, group_start);
223 priv->mux &= ~mask;
224 priv->mux |= mux ? mask : 0;
225
226 for (i = group_start; i < group_end; i++) {
227 priv->pins_param[i] = 0;
228 priv->pins_value[i] = 0;
229 }
230
231 return 0;
232 }
233
sandbox_pinmux_property_set(struct udevice * dev,u32 pinmux_group)234 static int sandbox_pinmux_property_set(struct udevice *dev, u32 pinmux_group)
235 {
236 int ret;
237 unsigned pin_selector = pinmux_group & 0xFFFF;
238 unsigned func_selector = pinmux_group >> 16;
239
240 ret = sandbox_pinmux_set(dev, pin_selector, func_selector);
241 return ret ? ret : pin_selector;
242 }
243
sandbox_pinconf_set(struct udevice * dev,unsigned pin_selector,unsigned param,unsigned argument)244 static int sandbox_pinconf_set(struct udevice *dev, unsigned pin_selector,
245 unsigned param, unsigned argument)
246 {
247 struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
248
249 debug("sandbox pinconf: pin = %d (%s), param = %d, arg = %d\n",
250 pin_selector, sandbox_get_pin_name(dev, pin_selector),
251 param, argument);
252
253 priv->pins_param[pin_selector] |= BIT(param);
254 if (argument)
255 priv->pins_value[pin_selector] |= BIT(param);
256 else
257 priv->pins_value[pin_selector] &= ~BIT(param);
258
259 return 0;
260 }
261
sandbox_pinconf_group_set(struct udevice * dev,unsigned group_selector,unsigned param,unsigned argument)262 static int sandbox_pinconf_group_set(struct udevice *dev,
263 unsigned group_selector,
264 unsigned param, unsigned argument)
265 {
266 debug("sandbox pinconf: group = %d (%s), param = %d, arg = %d\n",
267 group_selector, sandbox_get_group_name(dev, group_selector),
268 param, argument);
269
270 return 0;
271 }
272
273 const struct pinctrl_ops sandbox_pinctrl_ops = {
274 .get_pins_count = sandbox_get_pins_count,
275 .get_pin_name = sandbox_get_pin_name,
276 .get_pin_muxing = sandbox_get_pin_muxing,
277 .get_groups_count = sandbox_get_groups_count,
278 .get_group_name = sandbox_get_group_name,
279 .get_functions_count = sandbox_get_functions_count,
280 .get_function_name = sandbox_get_function_name,
281 .pinmux_set = sandbox_pinmux_set,
282 .pinmux_group_set = sandbox_pinmux_group_set,
283 .pinmux_property_set = sandbox_pinmux_property_set,
284 .pinconf_num_params = ARRAY_SIZE(sandbox_conf_params),
285 .pinconf_params = sandbox_conf_params,
286 .pinconf_set = sandbox_pinconf_set,
287 .pinconf_group_set = sandbox_pinconf_group_set,
288 .set_state = pinctrl_generic_set_state,
289 };
290
291 static const struct udevice_id sandbox_pinctrl_match[] = {
292 { .compatible = "sandbox,pinctrl" },
293 { /* sentinel */ }
294 };
295
296 U_BOOT_DRIVER(sandbox_pinctrl) = {
297 .name = "sandbox_pinctrl",
298 .id = UCLASS_PINCTRL,
299 .of_match = sandbox_pinctrl_match,
300 .priv_auto = sizeof(struct sandbox_pinctrl_priv),
301 .ops = &sandbox_pinctrl_ops,
302 };
303