xref: /linux/drivers/pinctrl/spear/pinctrl-spear.c (revision 52338415) 
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/module.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 #include <linux/of_gpio.h>
21 #include <linux/pinctrl/machine.h>
22 #include <linux/pinctrl/pinctrl.h>
23 #include <linux/pinctrl/pinmux.h>
24 #include <linux/platform_device.h>
25 #include <linux/slab.h>
26 
27 #include "pinctrl-spear.h"
28 
29 #define DRIVER_NAME "spear-pinmux"
30 
31 static void muxregs_endisable(struct spear_pmx *pmx,
32 		struct spear_muxreg *muxregs, u8 count, bool enable)
33 {
34 	struct spear_muxreg *muxreg;
35 	u32 val, temp, j;
36 
37 	for (j = 0; j < count; j++) {
38 		muxreg = &muxregs[j];
39 
40 		val = pmx_readl(pmx, muxreg->reg);
41 		val &= ~muxreg->mask;
42 
43 		if (enable)
44 			temp = muxreg->val;
45 		else
46 			temp = ~muxreg->val;
47 
48 		val |= muxreg->mask & temp;
49 		pmx_writel(pmx, val, muxreg->reg);
50 	}
51 }
52 
53 static int set_mode(struct spear_pmx *pmx, int mode)
54 {
55 	struct spear_pmx_mode *pmx_mode = NULL;
56 	int i;
57 	u32 val;
58 
59 	if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
60 		return -EINVAL;
61 
62 	for (i = 0; i < pmx->machdata->npmx_modes; i++) {
63 		if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
64 			pmx_mode = pmx->machdata->pmx_modes[i];
65 			break;
66 		}
67 	}
68 
69 	if (!pmx_mode)
70 		return -EINVAL;
71 
72 	val = pmx_readl(pmx, pmx_mode->reg);
73 	val &= ~pmx_mode->mask;
74 	val |= pmx_mode->val;
75 	pmx_writel(pmx, val, pmx_mode->reg);
76 
77 	pmx->machdata->mode = pmx_mode->mode;
78 	dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
79 			pmx_mode->name ? pmx_mode->name : "no_name",
80 			pmx_mode->reg);
81 
82 	return 0;
83 }
84 
85 void pmx_init_gpio_pingroup_addr(struct spear_gpio_pingroup *gpio_pingroup,
86 				 unsigned count, u16 reg)
87 {
88 	int i, j;
89 
90 	for (i = 0; i < count; i++)
91 		for (j = 0; j < gpio_pingroup[i].nmuxregs; j++)
92 			gpio_pingroup[i].muxregs[j].reg = reg;
93 }
94 
95 void pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
96 {
97 	struct spear_pingroup *pgroup;
98 	struct spear_modemux *modemux;
99 	int i, j, group;
100 
101 	for (group = 0; group < machdata->ngroups; group++) {
102 		pgroup = machdata->groups[group];
103 
104 		for (i = 0; i < pgroup->nmodemuxs; i++) {
105 			modemux = &pgroup->modemuxs[i];
106 
107 			for (j = 0; j < modemux->nmuxregs; j++)
108 				if (modemux->muxregs[j].reg == 0xFFFF)
109 					modemux->muxregs[j].reg = reg;
110 		}
111 	}
112 }
113 
114 static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
115 {
116 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
117 
118 	return pmx->machdata->ngroups;
119 }
120 
121 static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
122 		unsigned group)
123 {
124 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
125 
126 	return pmx->machdata->groups[group]->name;
127 }
128 
129 static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
130 		unsigned group, const unsigned **pins, unsigned *num_pins)
131 {
132 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
133 
134 	*pins = pmx->machdata->groups[group]->pins;
135 	*num_pins = pmx->machdata->groups[group]->npins;
136 
137 	return 0;
138 }
139 
140 static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
141 		struct seq_file *s, unsigned offset)
142 {
143 	seq_printf(s, " " DRIVER_NAME);
144 }
145 
146 static int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
147 					struct device_node *np_config,
148 					struct pinctrl_map **map,
149 					unsigned *num_maps)
150 {
151 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
152 	struct device_node *np;
153 	struct property *prop;
154 	const char *function, *group;
155 	int ret, index = 0, count = 0;
156 
157 	/* calculate number of maps required */
158 	for_each_child_of_node(np_config, np) {
159 		ret = of_property_read_string(np, "st,function", &function);
160 		if (ret < 0) {
161 			of_node_put(np);
162 			return ret;
163 		}
164 
165 		ret = of_property_count_strings(np, "st,pins");
166 		if (ret < 0) {
167 			of_node_put(np);
168 			return ret;
169 		}
170 
171 		count += ret;
172 	}
173 
174 	if (!count) {
175 		dev_err(pmx->dev, "No child nodes passed via DT\n");
176 		return -ENODEV;
177 	}
178 
179 	*map = kcalloc(count, sizeof(**map), GFP_KERNEL);
180 	if (!*map)
181 		return -ENOMEM;
182 
183 	for_each_child_of_node(np_config, np) {
184 		of_property_read_string(np, "st,function", &function);
185 		of_property_for_each_string(np, "st,pins", prop, group) {
186 			(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
187 			(*map)[index].data.mux.group = group;
188 			(*map)[index].data.mux.function = function;
189 			index++;
190 		}
191 	}
192 
193 	*num_maps = count;
194 
195 	return 0;
196 }
197 
198 static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
199 				      struct pinctrl_map *map,
200 				      unsigned num_maps)
201 {
202 	kfree(map);
203 }
204 
205 static const struct pinctrl_ops spear_pinctrl_ops = {
206 	.get_groups_count = spear_pinctrl_get_groups_cnt,
207 	.get_group_name = spear_pinctrl_get_group_name,
208 	.get_group_pins = spear_pinctrl_get_group_pins,
209 	.pin_dbg_show = spear_pinctrl_pin_dbg_show,
210 	.dt_node_to_map = spear_pinctrl_dt_node_to_map,
211 	.dt_free_map = spear_pinctrl_dt_free_map,
212 };
213 
214 static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
215 {
216 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
217 
218 	return pmx->machdata->nfunctions;
219 }
220 
221 static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
222 		unsigned function)
223 {
224 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
225 
226 	return pmx->machdata->functions[function]->name;
227 }
228 
229 static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
230 		unsigned function, const char *const **groups,
231 		unsigned * const ngroups)
232 {
233 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
234 
235 	*groups = pmx->machdata->functions[function]->groups;
236 	*ngroups = pmx->machdata->functions[function]->ngroups;
237 
238 	return 0;
239 }
240 
241 static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
242 		unsigned function, unsigned group, bool enable)
243 {
244 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
245 	const struct spear_pingroup *pgroup;
246 	const struct spear_modemux *modemux;
247 	int i;
248 	bool found = false;
249 
250 	pgroup = pmx->machdata->groups[group];
251 
252 	for (i = 0; i < pgroup->nmodemuxs; i++) {
253 		modemux = &pgroup->modemuxs[i];
254 
255 		/* SoC have any modes */
256 		if (pmx->machdata->modes_supported) {
257 			if (!(pmx->machdata->mode & modemux->modes))
258 				continue;
259 		}
260 
261 		found = true;
262 		muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
263 				enable);
264 	}
265 
266 	if (!found) {
267 		dev_err(pmx->dev, "pinmux group: %s not supported\n",
268 				pgroup->name);
269 		return -ENODEV;
270 	}
271 
272 	return 0;
273 }
274 
275 static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
276 		unsigned group)
277 {
278 	return spear_pinctrl_endisable(pctldev, function, group, true);
279 }
280 
281 /* gpio with pinmux */
282 static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
283 		unsigned pin)
284 {
285 	struct spear_gpio_pingroup *gpio_pingroup;
286 	int i, j;
287 
288 	if (!pmx->machdata->gpio_pingroups)
289 		return NULL;
290 
291 	for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
292 		gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
293 
294 		for (j = 0; j < gpio_pingroup->npins; j++) {
295 			if (gpio_pingroup->pins[j] == pin)
296 				return gpio_pingroup;
297 		}
298 	}
299 
300 	return NULL;
301 }
302 
303 static int gpio_request_endisable(struct pinctrl_dev *pctldev,
304 		struct pinctrl_gpio_range *range, unsigned offset, bool enable)
305 {
306 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
307 	struct spear_pinctrl_machdata *machdata = pmx->machdata;
308 	struct spear_gpio_pingroup *gpio_pingroup;
309 
310 	/*
311 	 * Some SoC have configuration options applicable to group of pins,
312 	 * rather than a single pin.
313 	 */
314 	gpio_pingroup = get_gpio_pingroup(pmx, offset);
315 	if (gpio_pingroup)
316 		muxregs_endisable(pmx, gpio_pingroup->muxregs,
317 				gpio_pingroup->nmuxregs, enable);
318 
319 	/*
320 	 * SoC may need some extra configurations, or configurations for single
321 	 * pin
322 	 */
323 	if (machdata->gpio_request_endisable)
324 		machdata->gpio_request_endisable(pmx, offset, enable);
325 
326 	return 0;
327 }
328 
329 static int gpio_request_enable(struct pinctrl_dev *pctldev,
330 		struct pinctrl_gpio_range *range, unsigned offset)
331 {
332 	return gpio_request_endisable(pctldev, range, offset, true);
333 }
334 
335 static void gpio_disable_free(struct pinctrl_dev *pctldev,
336 		struct pinctrl_gpio_range *range, unsigned offset)
337 {
338 	gpio_request_endisable(pctldev, range, offset, false);
339 }
340 
341 static const struct pinmux_ops spear_pinmux_ops = {
342 	.get_functions_count = spear_pinctrl_get_funcs_count,
343 	.get_function_name = spear_pinctrl_get_func_name,
344 	.get_function_groups = spear_pinctrl_get_func_groups,
345 	.set_mux = spear_pinctrl_set_mux,
346 	.gpio_request_enable = gpio_request_enable,
347 	.gpio_disable_free = gpio_disable_free,
348 };
349 
350 static struct pinctrl_desc spear_pinctrl_desc = {
351 	.name = DRIVER_NAME,
352 	.pctlops = &spear_pinctrl_ops,
353 	.pmxops = &spear_pinmux_ops,
354 	.owner = THIS_MODULE,
355 };
356 
357 int spear_pinctrl_probe(struct platform_device *pdev,
358 			struct spear_pinctrl_machdata *machdata)
359 {
360 	struct device_node *np = pdev->dev.of_node;
361 	struct resource *res;
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 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
372 	pmx->vbase = devm_ioremap_resource(&pdev->dev, res);
373 	if (IS_ERR(pmx->vbase))
374 		return PTR_ERR(pmx->vbase);
375 
376 	pmx->dev = &pdev->dev;
377 	pmx->machdata = machdata;
378 
379 	/* configure mode, if supported by SoC */
380 	if (machdata->modes_supported) {
381 		int mode = 0;
382 
383 		if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
384 			dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
385 			return -EINVAL;
386 		}
387 
388 		if (set_mode(pmx, mode)) {
389 			dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
390 					mode);
391 			return -EINVAL;
392 		}
393 	}
394 
395 	platform_set_drvdata(pdev, pmx);
396 
397 	spear_pinctrl_desc.pins = machdata->pins;
398 	spear_pinctrl_desc.npins = machdata->npins;
399 
400 	pmx->pctl = devm_pinctrl_register(&pdev->dev, &spear_pinctrl_desc, pmx);
401 	if (IS_ERR(pmx->pctl)) {
402 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
403 		return PTR_ERR(pmx->pctl);
404 	}
405 
406 	return 0;
407 }
408