1 /*
2  * Driver for the ST Microelectronics SPEAr pinmux
3  *
4  * Copyright (C) 2012 ST Microelectronics
5  * Viresh Kumar <viresh.linux@gmail.com>
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 			return ret;
162 
163 		ret = of_property_count_strings(np, "st,pins");
164 		if (ret < 0)
165 			return ret;
166 
167 		count += ret;
168 	}
169 
170 	if (!count) {
171 		dev_err(pmx->dev, "No child nodes passed via DT\n");
172 		return -ENODEV;
173 	}
174 
175 	*map = kzalloc(sizeof(**map) * count, GFP_KERNEL);
176 	if (!*map)
177 		return -ENOMEM;
178 
179 	for_each_child_of_node(np_config, np) {
180 		of_property_read_string(np, "st,function", &function);
181 		of_property_for_each_string(np, "st,pins", prop, group) {
182 			(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
183 			(*map)[index].data.mux.group = group;
184 			(*map)[index].data.mux.function = function;
185 			index++;
186 		}
187 	}
188 
189 	*num_maps = count;
190 
191 	return 0;
192 }
193 
194 static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
195 				      struct pinctrl_map *map,
196 				      unsigned num_maps)
197 {
198 	kfree(map);
199 }
200 
201 static const struct pinctrl_ops spear_pinctrl_ops = {
202 	.get_groups_count = spear_pinctrl_get_groups_cnt,
203 	.get_group_name = spear_pinctrl_get_group_name,
204 	.get_group_pins = spear_pinctrl_get_group_pins,
205 	.pin_dbg_show = spear_pinctrl_pin_dbg_show,
206 	.dt_node_to_map = spear_pinctrl_dt_node_to_map,
207 	.dt_free_map = spear_pinctrl_dt_free_map,
208 };
209 
210 static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
211 {
212 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
213 
214 	return pmx->machdata->nfunctions;
215 }
216 
217 static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
218 		unsigned function)
219 {
220 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
221 
222 	return pmx->machdata->functions[function]->name;
223 }
224 
225 static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
226 		unsigned function, const char *const **groups,
227 		unsigned * const ngroups)
228 {
229 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
230 
231 	*groups = pmx->machdata->functions[function]->groups;
232 	*ngroups = pmx->machdata->functions[function]->ngroups;
233 
234 	return 0;
235 }
236 
237 static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
238 		unsigned function, unsigned group, bool enable)
239 {
240 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
241 	const struct spear_pingroup *pgroup;
242 	const struct spear_modemux *modemux;
243 	int i;
244 	bool found = false;
245 
246 	pgroup = pmx->machdata->groups[group];
247 
248 	for (i = 0; i < pgroup->nmodemuxs; i++) {
249 		modemux = &pgroup->modemuxs[i];
250 
251 		/* SoC have any modes */
252 		if (pmx->machdata->modes_supported) {
253 			if (!(pmx->machdata->mode & modemux->modes))
254 				continue;
255 		}
256 
257 		found = true;
258 		muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
259 				enable);
260 	}
261 
262 	if (!found) {
263 		dev_err(pmx->dev, "pinmux group: %s not supported\n",
264 				pgroup->name);
265 		return -ENODEV;
266 	}
267 
268 	return 0;
269 }
270 
271 static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
272 		unsigned group)
273 {
274 	return spear_pinctrl_endisable(pctldev, function, group, true);
275 }
276 
277 /* gpio with pinmux */
278 static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
279 		unsigned pin)
280 {
281 	struct spear_gpio_pingroup *gpio_pingroup;
282 	int i, j;
283 
284 	if (!pmx->machdata->gpio_pingroups)
285 		return NULL;
286 
287 	for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
288 		gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
289 
290 		for (j = 0; j < gpio_pingroup->npins; j++) {
291 			if (gpio_pingroup->pins[j] == pin)
292 				return gpio_pingroup;
293 		}
294 	}
295 
296 	return NULL;
297 }
298 
299 static int gpio_request_endisable(struct pinctrl_dev *pctldev,
300 		struct pinctrl_gpio_range *range, unsigned offset, bool enable)
301 {
302 	struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
303 	struct spear_pinctrl_machdata *machdata = pmx->machdata;
304 	struct spear_gpio_pingroup *gpio_pingroup;
305 
306 	/*
307 	 * Some SoC have configuration options applicable to group of pins,
308 	 * rather than a single pin.
309 	 */
310 	gpio_pingroup = get_gpio_pingroup(pmx, offset);
311 	if (gpio_pingroup)
312 		muxregs_endisable(pmx, gpio_pingroup->muxregs,
313 				gpio_pingroup->nmuxregs, enable);
314 
315 	/*
316 	 * SoC may need some extra configurations, or configurations for single
317 	 * pin
318 	 */
319 	if (machdata->gpio_request_endisable)
320 		machdata->gpio_request_endisable(pmx, offset, enable);
321 
322 	return 0;
323 }
324 
325 static int gpio_request_enable(struct pinctrl_dev *pctldev,
326 		struct pinctrl_gpio_range *range, unsigned offset)
327 {
328 	return gpio_request_endisable(pctldev, range, offset, true);
329 }
330 
331 static void gpio_disable_free(struct pinctrl_dev *pctldev,
332 		struct pinctrl_gpio_range *range, unsigned offset)
333 {
334 	gpio_request_endisable(pctldev, range, offset, false);
335 }
336 
337 static const struct pinmux_ops spear_pinmux_ops = {
338 	.get_functions_count = spear_pinctrl_get_funcs_count,
339 	.get_function_name = spear_pinctrl_get_func_name,
340 	.get_function_groups = spear_pinctrl_get_func_groups,
341 	.set_mux = spear_pinctrl_set_mux,
342 	.gpio_request_enable = gpio_request_enable,
343 	.gpio_disable_free = gpio_disable_free,
344 };
345 
346 static struct pinctrl_desc spear_pinctrl_desc = {
347 	.name = DRIVER_NAME,
348 	.pctlops = &spear_pinctrl_ops,
349 	.pmxops = &spear_pinmux_ops,
350 	.owner = THIS_MODULE,
351 };
352 
353 int spear_pinctrl_probe(struct platform_device *pdev,
354 			struct spear_pinctrl_machdata *machdata)
355 {
356 	struct device_node *np = pdev->dev.of_node;
357 	struct resource *res;
358 	struct spear_pmx *pmx;
359 
360 	if (!machdata)
361 		return -ENODEV;
362 
363 	pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
364 	if (!pmx) {
365 		dev_err(&pdev->dev, "Can't alloc spear_pmx\n");
366 		return -ENOMEM;
367 	}
368 
369 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
370 	pmx->vbase = devm_ioremap_resource(&pdev->dev, res);
371 	if (IS_ERR(pmx->vbase))
372 		return PTR_ERR(pmx->vbase);
373 
374 	pmx->dev = &pdev->dev;
375 	pmx->machdata = machdata;
376 
377 	/* configure mode, if supported by SoC */
378 	if (machdata->modes_supported) {
379 		int mode = 0;
380 
381 		if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
382 			dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
383 			return -EINVAL;
384 		}
385 
386 		if (set_mode(pmx, mode)) {
387 			dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
388 					mode);
389 			return -EINVAL;
390 		}
391 	}
392 
393 	platform_set_drvdata(pdev, pmx);
394 
395 	spear_pinctrl_desc.pins = machdata->pins;
396 	spear_pinctrl_desc.npins = machdata->npins;
397 
398 	pmx->pctl = pinctrl_register(&spear_pinctrl_desc, &pdev->dev, pmx);
399 	if (!pmx->pctl) {
400 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
401 		return -ENODEV;
402 	}
403 
404 	return 0;
405 }
406 
407 int spear_pinctrl_remove(struct platform_device *pdev)
408 {
409 	struct spear_pmx *pmx = platform_get_drvdata(pdev);
410 
411 	pinctrl_unregister(pmx->pctl);
412 
413 	return 0;
414 }
415