1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
4 */
5
6 #include <linux/module.h>
7 #include <linux/device.h>
8 #include <linux/io.h>
9 #include <linux/platform_device.h>
10 #include <linux/slab.h>
11 #include <linux/of.h>
12 #include <linux/pinctrl/pinctrl.h>
13 #include <linux/pinctrl/pinconf.h>
14 #include <linux/pinctrl/pinconf-generic.h>
15 #include <linux/pinctrl/pinmux.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/pinctrl/machine.h>
18
19 #include <asm/mach-ralink/ralink_regs.h>
20 #include <asm/mach-ralink/pinmux.h>
21 #include <asm/mach-ralink/mt7620.h>
22
23 #include "../core.h"
24 #include "../pinctrl-utils.h"
25
26 #define SYSC_REG_GPIO_MODE 0x60
27 #define SYSC_REG_GPIO_MODE2 0x64
28
29 struct rt2880_priv {
30 struct device *dev;
31
32 struct pinctrl_pin_desc *pads;
33 struct pinctrl_desc *desc;
34
35 struct rt2880_pmx_func **func;
36 int func_count;
37
38 struct rt2880_pmx_group *groups;
39 const char **group_names;
40 int group_count;
41
42 u8 *gpio;
43 int max_pins;
44 };
45
rt2880_get_group_count(struct pinctrl_dev * pctrldev)46 static int rt2880_get_group_count(struct pinctrl_dev *pctrldev)
47 {
48 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
49
50 return p->group_count;
51 }
52
rt2880_get_group_name(struct pinctrl_dev * pctrldev,unsigned int group)53 static const char *rt2880_get_group_name(struct pinctrl_dev *pctrldev,
54 unsigned int group)
55 {
56 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
57
58 return (group >= p->group_count) ? NULL : p->group_names[group];
59 }
60
rt2880_get_group_pins(struct pinctrl_dev * pctrldev,unsigned int group,const unsigned int ** pins,unsigned int * num_pins)61 static int rt2880_get_group_pins(struct pinctrl_dev *pctrldev,
62 unsigned int group,
63 const unsigned int **pins,
64 unsigned int *num_pins)
65 {
66 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
67
68 if (group >= p->group_count)
69 return -EINVAL;
70
71 *pins = p->groups[group].func[0].pins;
72 *num_pins = p->groups[group].func[0].pin_count;
73
74 return 0;
75 }
76
77 static const struct pinctrl_ops rt2880_pctrl_ops = {
78 .get_groups_count = rt2880_get_group_count,
79 .get_group_name = rt2880_get_group_name,
80 .get_group_pins = rt2880_get_group_pins,
81 .dt_node_to_map = pinconf_generic_dt_node_to_map_all,
82 .dt_free_map = pinconf_generic_dt_free_map,
83 };
84
rt2880_pmx_func_count(struct pinctrl_dev * pctrldev)85 static int rt2880_pmx_func_count(struct pinctrl_dev *pctrldev)
86 {
87 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
88
89 return p->func_count;
90 }
91
rt2880_pmx_func_name(struct pinctrl_dev * pctrldev,unsigned int func)92 static const char *rt2880_pmx_func_name(struct pinctrl_dev *pctrldev,
93 unsigned int func)
94 {
95 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
96
97 return p->func[func]->name;
98 }
99
rt2880_pmx_group_get_groups(struct pinctrl_dev * pctrldev,unsigned int func,const char * const ** groups,unsigned int * const num_groups)100 static int rt2880_pmx_group_get_groups(struct pinctrl_dev *pctrldev,
101 unsigned int func,
102 const char * const **groups,
103 unsigned int * const num_groups)
104 {
105 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
106
107 if (p->func[func]->group_count == 1)
108 *groups = &p->group_names[p->func[func]->groups[0]];
109 else
110 *groups = p->group_names;
111
112 *num_groups = p->func[func]->group_count;
113
114 return 0;
115 }
116
rt2880_pmx_group_enable(struct pinctrl_dev * pctrldev,unsigned int func,unsigned int group)117 static int rt2880_pmx_group_enable(struct pinctrl_dev *pctrldev,
118 unsigned int func, unsigned int group)
119 {
120 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
121 u32 mode = 0;
122 u32 reg = SYSC_REG_GPIO_MODE;
123 int i;
124 int shift;
125
126 /* dont allow double use */
127 if (p->groups[group].enabled) {
128 dev_err(p->dev, "%s is already enabled\n",
129 p->groups[group].name);
130 return -EBUSY;
131 }
132
133 p->groups[group].enabled = 1;
134 p->func[func]->enabled = 1;
135
136 shift = p->groups[group].shift;
137 if (shift >= 32) {
138 shift -= 32;
139 reg = SYSC_REG_GPIO_MODE2;
140 }
141 mode = rt_sysc_r32(reg);
142 mode &= ~(p->groups[group].mask << shift);
143
144 /* mark the pins as gpio */
145 for (i = 0; i < p->groups[group].func[0].pin_count; i++)
146 p->gpio[p->groups[group].func[0].pins[i]] = 1;
147
148 /* function 0 is gpio and needs special handling */
149 if (func == 0) {
150 mode |= p->groups[group].gpio << shift;
151 } else {
152 for (i = 0; i < p->func[func]->pin_count; i++)
153 p->gpio[p->func[func]->pins[i]] = 0;
154 mode |= p->func[func]->value << shift;
155 }
156 rt_sysc_w32(mode, reg);
157
158 return 0;
159 }
160
rt2880_pmx_group_gpio_request_enable(struct pinctrl_dev * pctrldev,struct pinctrl_gpio_range * range,unsigned int pin)161 static int rt2880_pmx_group_gpio_request_enable(struct pinctrl_dev *pctrldev,
162 struct pinctrl_gpio_range *range,
163 unsigned int pin)
164 {
165 struct rt2880_priv *p = pinctrl_dev_get_drvdata(pctrldev);
166
167 if (!p->gpio[pin]) {
168 dev_err(p->dev, "pin %d is not set to gpio mux\n", pin);
169 return -EINVAL;
170 }
171
172 return 0;
173 }
174
175 static const struct pinmux_ops rt2880_pmx_group_ops = {
176 .get_functions_count = rt2880_pmx_func_count,
177 .get_function_name = rt2880_pmx_func_name,
178 .get_function_groups = rt2880_pmx_group_get_groups,
179 .set_mux = rt2880_pmx_group_enable,
180 .gpio_request_enable = rt2880_pmx_group_gpio_request_enable,
181 };
182
183 static struct pinctrl_desc rt2880_pctrl_desc = {
184 .owner = THIS_MODULE,
185 .name = "rt2880-pinmux",
186 .pctlops = &rt2880_pctrl_ops,
187 .pmxops = &rt2880_pmx_group_ops,
188 };
189
190 static struct rt2880_pmx_func gpio_func = {
191 .name = "gpio",
192 };
193
rt2880_pinmux_index(struct rt2880_priv * p)194 static int rt2880_pinmux_index(struct rt2880_priv *p)
195 {
196 struct rt2880_pmx_group *mux = p->groups;
197 int i, j, c = 0;
198
199 /* count the mux functions */
200 while (mux->name) {
201 p->group_count++;
202 mux++;
203 }
204
205 /* allocate the group names array needed by the gpio function */
206 p->group_names = devm_kcalloc(p->dev, p->group_count,
207 sizeof(char *), GFP_KERNEL);
208 if (!p->group_names)
209 return -ENOMEM;
210
211 for (i = 0; i < p->group_count; i++) {
212 p->group_names[i] = p->groups[i].name;
213 p->func_count += p->groups[i].func_count;
214 }
215
216 /* we have a dummy function[0] for gpio */
217 p->func_count++;
218
219 /* allocate our function and group mapping index buffers */
220 p->func = devm_kcalloc(p->dev, p->func_count,
221 sizeof(*p->func), GFP_KERNEL);
222 gpio_func.groups = devm_kcalloc(p->dev, p->group_count, sizeof(int),
223 GFP_KERNEL);
224 if (!p->func || !gpio_func.groups)
225 return -ENOMEM;
226
227 /* add a backpointer to the function so it knows its group */
228 gpio_func.group_count = p->group_count;
229 for (i = 0; i < gpio_func.group_count; i++)
230 gpio_func.groups[i] = i;
231
232 p->func[c] = &gpio_func;
233 c++;
234
235 /* add remaining functions */
236 for (i = 0; i < p->group_count; i++) {
237 for (j = 0; j < p->groups[i].func_count; j++) {
238 p->func[c] = &p->groups[i].func[j];
239 p->func[c]->groups = devm_kzalloc(p->dev, sizeof(int),
240 GFP_KERNEL);
241 if (!p->func[c]->groups)
242 return -ENOMEM;
243 p->func[c]->groups[0] = i;
244 p->func[c]->group_count = 1;
245 c++;
246 }
247 }
248 return 0;
249 }
250
rt2880_pinmux_pins(struct rt2880_priv * p)251 static int rt2880_pinmux_pins(struct rt2880_priv *p)
252 {
253 int i, j;
254
255 /*
256 * loop over the functions and initialize the pins array.
257 * also work out the highest pin used.
258 */
259 for (i = 0; i < p->func_count; i++) {
260 int pin;
261
262 if (!p->func[i]->pin_count)
263 continue;
264
265 p->func[i]->pins = devm_kcalloc(p->dev,
266 p->func[i]->pin_count,
267 sizeof(int),
268 GFP_KERNEL);
269 for (j = 0; j < p->func[i]->pin_count; j++)
270 p->func[i]->pins[j] = p->func[i]->pin_first + j;
271
272 pin = p->func[i]->pin_first + p->func[i]->pin_count;
273 if (pin > p->max_pins)
274 p->max_pins = pin;
275 }
276
277 /* the buffer that tells us which pins are gpio */
278 p->gpio = devm_kcalloc(p->dev, p->max_pins, sizeof(u8), GFP_KERNEL);
279 /* the pads needed to tell pinctrl about our pins */
280 p->pads = devm_kcalloc(p->dev, p->max_pins,
281 sizeof(struct pinctrl_pin_desc), GFP_KERNEL);
282 if (!p->pads || !p->gpio)
283 return -ENOMEM;
284
285 memset(p->gpio, 1, sizeof(u8) * p->max_pins);
286 for (i = 0; i < p->func_count; i++) {
287 if (!p->func[i]->pin_count)
288 continue;
289
290 for (j = 0; j < p->func[i]->pin_count; j++)
291 p->gpio[p->func[i]->pins[j]] = 0;
292 }
293
294 /* pin 0 is always a gpio */
295 p->gpio[0] = 1;
296
297 /* set the pads */
298 for (i = 0; i < p->max_pins; i++) {
299 /* strlen("ioXY") + 1 = 5 */
300 char *name = devm_kzalloc(p->dev, 5, GFP_KERNEL);
301
302 if (!name)
303 return -ENOMEM;
304 snprintf(name, 5, "io%d", i);
305 p->pads[i].number = i;
306 p->pads[i].name = name;
307 }
308 p->desc->pins = p->pads;
309 p->desc->npins = p->max_pins;
310
311 return 0;
312 }
313
rt2880_pinmux_probe(struct platform_device * pdev)314 static int rt2880_pinmux_probe(struct platform_device *pdev)
315 {
316 struct rt2880_priv *p;
317 struct pinctrl_dev *dev;
318 int err;
319
320 if (!rt2880_pinmux_data)
321 return -ENOTSUPP;
322
323 /* setup the private data */
324 p = devm_kzalloc(&pdev->dev, sizeof(struct rt2880_priv), GFP_KERNEL);
325 if (!p)
326 return -ENOMEM;
327
328 p->dev = &pdev->dev;
329 p->desc = &rt2880_pctrl_desc;
330 p->groups = rt2880_pinmux_data;
331 platform_set_drvdata(pdev, p);
332
333 /* init the device */
334 err = rt2880_pinmux_index(p);
335 if (err) {
336 dev_err(&pdev->dev, "failed to load index\n");
337 return err;
338 }
339
340 err = rt2880_pinmux_pins(p);
341 if (err) {
342 dev_err(&pdev->dev, "failed to load pins\n");
343 return err;
344 }
345 dev = pinctrl_register(p->desc, &pdev->dev, p);
346
347 return PTR_ERR_OR_ZERO(dev);
348 }
349
350 static const struct of_device_id rt2880_pinmux_match[] = {
351 { .compatible = "ralink,rt2880-pinmux" },
352 {},
353 };
354 MODULE_DEVICE_TABLE(of, rt2880_pinmux_match);
355
356 static struct platform_driver rt2880_pinmux_driver = {
357 .probe = rt2880_pinmux_probe,
358 .driver = {
359 .name = "rt2880-pinmux",
360 .of_match_table = rt2880_pinmux_match,
361 },
362 };
363
rt2880_pinmux_init(void)364 static int __init rt2880_pinmux_init(void)
365 {
366 return platform_driver_register(&rt2880_pinmux_driver);
367 }
368
369 core_initcall_sync(rt2880_pinmux_init);
370