xref: /linux/drivers/pinctrl/spear/pinctrl-spear.c (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04) 
1 /*
2  * Driver for the ST Microelectronics SPEAr pinmux
3  *
4  * Copyright (C) 2012 ST Microelectronics
5  * Viresh Kumar <vireshk@kernel.org>
6  *
7  * Inspired from:
8  * - U300 Pinctl drivers
9  * - Tegra Pinctl drivers
10  *
11  * This file is licensed under the terms of the GNU General Public
12  * License version 2. This program is licensed "as is" without any
13  * warranty of any kind, whether express or implied.
14  */
15 
16 #include <linux/err.h>
17 #include <linux/mfd/syscon.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 #include <linux/of_gpio.h>
22 #include <linux/pinctrl/machine.h>
23 #include <linux/pinctrl/pinctrl.h>
24 #include <linux/pinctrl/pinmux.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
27 
28 #include "pinctrl-spear.h"
29 
30 #define DRIVER_NAME "spear-pinmux"
31 
32 static void muxregs_endisable(struct spear_pmx *pmx,
33 		struct spear_muxreg *muxregs, u8 count, bool enable)
34 {
35 	struct spear_muxreg *muxreg;
36 	u32 val, temp, j;
37 
38 	for (j = 0; j < count; j++) {
39 		muxreg = &muxregs[j];
40 
41 		val = pmx_readl(pmx, muxreg->reg);
42 		val &= ~muxreg->mask;
43 
44 		if (enable)
45 			temp = muxreg->val;
46 		else
47 			temp = ~muxreg->val;
48 
49 		val |= muxreg->mask & temp;
50 		pmx_writel(pmx, val, muxreg->reg);
51 	}
52 }
53 
54 static int set_mode(struct spear_pmx *pmx, int mode)
55 {
56 	struct spear_pmx_mode *pmx_mode = NULL;
57 	int i;
58 	u32 val;
59 
60 	if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
61 		return -EINVAL;
62 
63 	for (i = 0; i < pmx->machdata->npmx_modes; i++) {
64 		if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
65 			pmx_mode = pmx->machdata->pmx_modes[i];
66 			break;
67 		}
68 	}
69 
70 	if (!pmx_mode)
71 		return -EINVAL;
72 
73 	val = pmx_readl(pmx, pmx_mode->reg);
74 	val &= ~pmx_mode->mask;
75 	val |= pmx_mode->val;
76 	pmx_writel(pmx, val, pmx_mode->reg);
77 
78 	pmx->machdata->mode = pmx_mode->mode;
79 	dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
80 			pmx_mode->name ? pmx_mode->name : "no_name",
81 			pmx_mode->reg);
82 
83 	return 0;
84 }
85 
86 void pmx_init_gpio_pingroup_addr(struct spear_gpio_pingroup *gpio_pingroup,
87 				 unsigned count, u16 reg)
88 {
89 	int i, j;
90 
91 	for (i = 0; i < count; i++)
92 		for (j = 0; j < gpio_pingroup[i].nmuxregs; j++)
93 			gpio_pingroup[i].muxregs[j].reg = reg;
94 }
95 
96 void pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
97 {
98 	struct spear_pingroup *pgroup;
99 	struct spear_modemux *modemux;
100 	int i, j, group;
101 
102 	for (group = 0; group < machdata->ngroups; group++) {
103 		pgroup = machdata->groups[group];
104 
105 		for (i = 0; i < pgroup->nmodemuxs; i++) {
106 			modemux = &pgroup->modemuxs[i];
107 
108 			for (j = 0; j < modemux->nmuxregs; j++)
109 				if (modemux->muxregs[j].reg == 0xFFFF)
110 					modemux->muxregs[j].reg = reg;
111 		}
112 	}
113 }
114 
115 static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
116 {
117 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
118 
119 	return pmx->machdata->ngroups;
120 }
121 
122 static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
123 		unsigned group)
124 {
125 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
126 
127 	return pmx->machdata->groups[group]->name;
128 }
129 
130 static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
131 		unsigned group, const unsigned **pins, unsigned *num_pins)
132 {
133 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
134 
135 	*pins = pmx->machdata->groups[group]->pins;
136 	*num_pins = pmx->machdata->groups[group]->npins;
137 
138 	return 0;
139 }
140 
141 static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
142 		struct seq_file *s, unsigned offset)
143 {
144 	seq_printf(s, " " DRIVER_NAME);
145 }
146 
147 static int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
148 					struct device_node *np_config,
149 					struct pinctrl_map **map,
150 					unsigned *num_maps)
151 {
152 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
153 	struct device_node *np;
154 	struct property *prop;
155 	const char *function, *group;
156 	int ret, index = 0, count = 0;
157 
158 	/* calculate number of maps required */
159 	for_each_child_of_node(np_config, np) {
160 		ret = of_property_read_string(np, "st,function", &function);
161 		if (ret < 0) {
162 			of_node_put(np);
163 			return ret;
164 		}
165 
166 		ret = of_property_count_strings(np, "st,pins");
167 		if (ret < 0) {
168 			of_node_put(np);
169 			return ret;
170 		}
171 
172 		count += ret;
173 	}
174 
175 	if (!count) {
176 		dev_err(pmx->dev, "No child nodes passed via DT\n");
177 		return -ENODEV;
178 	}
179 
180 	*map = kcalloc(count, sizeof(**map), GFP_KERNEL);
181 	if (!*map)
182 		return -ENOMEM;
183 
184 	for_each_child_of_node(np_config, np) {
185 		of_property_read_string(np, "st,function", &function);
186 		of_property_for_each_string(np, "st,pins", prop, group) {
187 			(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
188 			(*map)[index].data.mux.group = group;
189 			(*map)[index].data.mux.function = function;
190 			index++;
191 		}
192 	}
193 
194 	*num_maps = count;
195 
196 	return 0;
197 }
198 
199 static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
200 				      struct pinctrl_map *map,
201 				      unsigned num_maps)
202 {
203 	kfree(map);
204 }
205 
206 static const struct pinctrl_ops spear_pinctrl_ops = {
207 	.get_groups_count = spear_pinctrl_get_groups_cnt,
208 	.get_group_name = spear_pinctrl_get_group_name,
209 	.get_group_pins = spear_pinctrl_get_group_pins,
210 	.pin_dbg_show = spear_pinctrl_pin_dbg_show,
211 	.dt_node_to_map = spear_pinctrl_dt_node_to_map,
212 	.dt_free_map = spear_pinctrl_dt_free_map,
213 };
214 
215 static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
216 {
217 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
218 
219 	return pmx->machdata->nfunctions;
220 }
221 
222 static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
223 		unsigned function)
224 {
225 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
226 
227 	return pmx->machdata->functions[function]->name;
228 }
229 
230 static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
231 		unsigned function, const char *const **groups,
232 		unsigned * const ngroups)
233 {
234 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
235 
236 	*groups = pmx->machdata->functions[function]->groups;
237 	*ngroups = pmx->machdata->functions[function]->ngroups;
238 
239 	return 0;
240 }
241 
242 static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
243 		unsigned function, unsigned group, bool enable)
244 {
245 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
246 	const struct spear_pingroup *pgroup;
247 	const struct spear_modemux *modemux;
248 	int i;
249 	bool found = false;
250 
251 	pgroup = pmx->machdata->groups[group];
252 
253 	for (i = 0; i < pgroup->nmodemuxs; i++) {
254 		modemux = &pgroup->modemuxs[i];
255 
256 		/* SoC have any modes */
257 		if (pmx->machdata->modes_supported) {
258 			if (!(pmx->machdata->mode & modemux->modes))
259 				continue;
260 		}
261 
262 		found = true;
263 		muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
264 				enable);
265 	}
266 
267 	if (!found) {
268 		dev_err(pmx->dev, "pinmux group: %s not supported\n",
269 				pgroup->name);
270 		return -ENODEV;
271 	}
272 
273 	return 0;
274 }
275 
276 static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
277 		unsigned group)
278 {
279 	return spear_pinctrl_endisable(pctldev, function, group, true);
280 }
281 
282 /* gpio with pinmux */
283 static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
284 		unsigned pin)
285 {
286 	struct spear_gpio_pingroup *gpio_pingroup;
287 	int i, j;
288 
289 	if (!pmx->machdata->gpio_pingroups)
290 		return NULL;
291 
292 	for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
293 		gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
294 
295 		for (j = 0; j < gpio_pingroup->npins; j++) {
296 			if (gpio_pingroup->pins[j] == pin)
297 				return gpio_pingroup;
298 		}
299 	}
300 
301 	return NULL;
302 }
303 
304 static int gpio_request_endisable(struct pinctrl_dev *pctldev,
305 		struct pinctrl_gpio_range *range, unsigned offset, bool enable)
306 {
307 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
308 	struct spear_pinctrl_machdata *machdata = pmx->machdata;
309 	struct spear_gpio_pingroup *gpio_pingroup;
310 
311 	/*
312 	 * Some SoC have configuration options applicable to group of pins,
313 	 * rather than a single pin.
314 	 */
315 	gpio_pingroup = get_gpio_pingroup(pmx, offset);
316 	if (gpio_pingroup)
317 		muxregs_endisable(pmx, gpio_pingroup->muxregs,
318 				gpio_pingroup->nmuxregs, enable);
319 
320 	/*
321 	 * SoC may need some extra configurations, or configurations for single
322 	 * pin
323 	 */
324 	if (machdata->gpio_request_endisable)
325 		machdata->gpio_request_endisable(pmx, offset, enable);
326 
327 	return 0;
328 }
329 
330 static int gpio_request_enable(struct pinctrl_dev *pctldev,
331 		struct pinctrl_gpio_range *range, unsigned offset)
332 {
333 	return gpio_request_endisable(pctldev, range, offset, true);
334 }
335 
336 static void gpio_disable_free(struct pinctrl_dev *pctldev,
337 		struct pinctrl_gpio_range *range, unsigned offset)
338 {
339 	gpio_request_endisable(pctldev, range, offset, false);
340 }
341 
342 static const struct pinmux_ops spear_pinmux_ops = {
343 	.get_functions_count = spear_pinctrl_get_funcs_count,
344 	.get_function_name = spear_pinctrl_get_func_name,
345 	.get_function_groups = spear_pinctrl_get_func_groups,
346 	.set_mux = spear_pinctrl_set_mux,
347 	.gpio_request_enable = gpio_request_enable,
348 	.gpio_disable_free = gpio_disable_free,
349 };
350 
351 static struct pinctrl_desc spear_pinctrl_desc = {
352 	.name = DRIVER_NAME,
353 	.pctlops = &spear_pinctrl_ops,
354 	.pmxops = &spear_pinmux_ops,
355 	.owner = THIS_MODULE,
356 };
357 
358 int spear_pinctrl_probe(struct platform_device *pdev,
359 			struct spear_pinctrl_machdata *machdata)
360 {
361 	struct device_node *np = pdev->dev.of_node;
362 	struct spear_pmx *pmx;
363 
364 	if (!machdata)
365 		return -ENODEV;
366 
367 	pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
368 	if (!pmx)
369 		return -ENOMEM;
370 
371 	pmx->regmap = device_node_to_regmap(np);
372 	if (IS_ERR(pmx->regmap)) {
373 		dev_err(&pdev->dev, "Init regmap failed (%pe).\n",
374 			pmx->regmap);
375 		return PTR_ERR(pmx->regmap);
376 	}
377 
378 	pmx->dev = &pdev->dev;
379 	pmx->machdata = machdata;
380 
381 	/* configure mode, if supported by SoC */
382 	if (machdata->modes_supported) {
383 		int mode = 0;
384 
385 		if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
386 			dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
387 			return -EINVAL;
388 		}
389 
390 		if (set_mode(pmx, mode)) {
391 			dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
392 					mode);
393 			return -EINVAL;
394 		}
395 	}
396 
397 	platform_set_drvdata(pdev, pmx);
398 
399 	spear_pinctrl_desc.pins = machdata->pins;
400 	spear_pinctrl_desc.npins = machdata->npins;
401 
402 	pmx->pctl = devm_pinctrl_register(&pdev->dev, &spear_pinctrl_desc, pmx);
403 	if (IS_ERR(pmx->pctl)) {
404 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
405 		return PTR_ERR(pmx->pctl);
406 	}
407 
408 	return 0;
409 }
410