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/mt7620.h>
21
22#include "pinctrl-mtmips.h"
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
29struct mtmips_priv {
30	struct device *dev;
31
32	struct pinctrl_pin_desc *pads;
33	struct pinctrl_desc *desc;
34
35	struct mtmips_pmx_func **func;
36	int func_count;
37
38	struct mtmips_pmx_group *groups;
39	const char **group_names;
40	int group_count;
41
42	u8 *gpio;
43	int max_pins;
44};
45
46static int mtmips_get_group_count(struct pinctrl_dev *pctrldev)
47{
48	struct mtmips_priv *p = pinctrl_dev_get_drvdata(pctrldev);
49
50	return p->group_count;
51}
52
53static const char *mtmips_get_group_name(struct pinctrl_dev *pctrldev,
54					 unsigned int group)
55{
56	struct mtmips_priv *p = pinctrl_dev_get_drvdata(pctrldev);
57
58	return (group >= p->group_count) ? NULL : p->group_names[group];
59}
60
61static int mtmips_get_group_pins(struct pinctrl_dev *pctrldev,
62				 unsigned int group,
63				 const unsigned int **pins,
64				 unsigned int *num_pins)
65{
66	struct mtmips_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
77static const struct pinctrl_ops mtmips_pctrl_ops = {
78	.get_groups_count	= mtmips_get_group_count,
79	.get_group_name		= mtmips_get_group_name,
80	.get_group_pins		= mtmips_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
85static int mtmips_pmx_func_count(struct pinctrl_dev *pctrldev)
86{
87	struct mtmips_priv *p = pinctrl_dev_get_drvdata(pctrldev);
88
89	return p->func_count;
90}
91
92static const char *mtmips_pmx_func_name(struct pinctrl_dev *pctrldev,
93					unsigned int func)
94{
95	struct mtmips_priv *p = pinctrl_dev_get_drvdata(pctrldev);
96
97	return p->func[func]->name;
98}
99
100static int mtmips_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 mtmips_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
117static int mtmips_pmx_group_enable(struct pinctrl_dev *pctrldev,
118				   unsigned int func, unsigned int group)
119{
120	struct mtmips_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 0;
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
161static int mtmips_pmx_group_gpio_request_enable(struct pinctrl_dev *pctrldev,
162						struct pinctrl_gpio_range *range,
163						unsigned int pin)
164{
165	struct mtmips_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
175static const struct pinmux_ops mtmips_pmx_group_ops = {
176	.get_functions_count	= mtmips_pmx_func_count,
177	.get_function_name	= mtmips_pmx_func_name,
178	.get_function_groups	= mtmips_pmx_group_get_groups,
179	.set_mux		= mtmips_pmx_group_enable,
180	.gpio_request_enable	= mtmips_pmx_group_gpio_request_enable,
181};
182
183static struct pinctrl_desc mtmips_pctrl_desc = {
184	.owner		= THIS_MODULE,
185	.name		= "mtmips-pinctrl",
186	.pctlops	= &mtmips_pctrl_ops,
187	.pmxops		= &mtmips_pmx_group_ops,
188};
189
190static struct mtmips_pmx_func gpio_func = {
191	.name = "gpio",
192};
193
194static int mtmips_pinctrl_index(struct mtmips_priv *p)
195{
196	struct mtmips_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
251static int mtmips_pinctrl_pins(struct mtmips_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		if (!p->func[i]->pins)
270			return -ENOMEM;
271		for (j = 0; j < p->func[i]->pin_count; j++)
272			p->func[i]->pins[j] = p->func[i]->pin_first + j;
273
274		pin = p->func[i]->pin_first + p->func[i]->pin_count;
275		if (pin > p->max_pins)
276			p->max_pins = pin;
277	}
278
279	/* the buffer that tells us which pins are gpio */
280	p->gpio = devm_kcalloc(p->dev, p->max_pins, sizeof(u8), GFP_KERNEL);
281	/* the pads needed to tell pinctrl about our pins */
282	p->pads = devm_kcalloc(p->dev, p->max_pins,
283			       sizeof(struct pinctrl_pin_desc), GFP_KERNEL);
284	if (!p->pads || !p->gpio)
285		return -ENOMEM;
286
287	memset(p->gpio, 1, sizeof(u8) * p->max_pins);
288	for (i = 0; i < p->func_count; i++) {
289		if (!p->func[i]->pin_count)
290			continue;
291
292		for (j = 0; j < p->func[i]->pin_count; j++)
293			p->gpio[p->func[i]->pins[j]] = 0;
294	}
295
296	/* pin 0 is always a gpio */
297	p->gpio[0] = 1;
298
299	/* set the pads */
300	for (i = 0; i < p->max_pins; i++) {
301		/* strlen("ioXY") + 1 = 5 */
302		char *name = devm_kzalloc(p->dev, 5, GFP_KERNEL);
303
304		if (!name)
305			return -ENOMEM;
306		snprintf(name, 5, "io%d", i);
307		p->pads[i].number = i;
308		p->pads[i].name = name;
309	}
310	p->desc->pins = p->pads;
311	p->desc->npins = p->max_pins;
312
313	return 0;
314}
315
316int mtmips_pinctrl_init(struct platform_device *pdev,
317			struct mtmips_pmx_group *data)
318{
319	struct mtmips_priv *p;
320	struct pinctrl_dev *dev;
321	int err;
322
323	if (!data)
324		return -ENOTSUPP;
325
326	/* setup the private data */
327	p = devm_kzalloc(&pdev->dev, sizeof(struct mtmips_priv), GFP_KERNEL);
328	if (!p)
329		return -ENOMEM;
330
331	p->dev = &pdev->dev;
332	p->desc = &mtmips_pctrl_desc;
333	p->groups = data;
334	platform_set_drvdata(pdev, p);
335
336	/* init the device */
337	err = mtmips_pinctrl_index(p);
338	if (err) {
339		dev_err(&pdev->dev, "failed to load index\n");
340		return err;
341	}
342
343	err = mtmips_pinctrl_pins(p);
344	if (err) {
345		dev_err(&pdev->dev, "failed to load pins\n");
346		return err;
347	}
348	dev = pinctrl_register(p->desc, &pdev->dev, p);
349
350	return PTR_ERR_OR_ZERO(dev);
351}
352