1 /*
2  * Core driver for the imx pin controller in imx1/21/27
3  *
4  * Copyright (C) 2013 Pengutronix
5  * Author: Markus Pargmann <mpa@pengutronix.de>
6  *
7  * Based on pinctrl-imx.c:
8  *	Author: Dong Aisheng <dong.aisheng@linaro.org>
9  *	Copyright (C) 2012 Freescale Semiconductor, Inc.
10  *	Copyright (C) 2012 Linaro Ltd.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  */
17 
18 #include <linux/bitops.h>
19 #include <linux/err.h>
20 #include <linux/init.h>
21 #include <linux/io.h>
22 #include <linux/module.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/pinctrl/machine.h>
26 #include <linux/pinctrl/pinconf.h>
27 #include <linux/pinctrl/pinctrl.h>
28 #include <linux/pinctrl/pinmux.h>
29 #include <linux/slab.h>
30 
31 #include "../core.h"
32 #include "pinctrl-imx1.h"
33 
34 struct imx1_pinctrl {
35 	struct device *dev;
36 	struct pinctrl_dev *pctl;
37 	void __iomem *base;
38 	const struct imx1_pinctrl_soc_info *info;
39 };
40 
41 /*
42  * MX1 register offsets
43  */
44 
45 #define MX1_DDIR 0x00
46 #define MX1_OCR 0x04
47 #define MX1_ICONFA 0x0c
48 #define MX1_ICONFB 0x14
49 #define MX1_GIUS 0x20
50 #define MX1_GPR 0x38
51 #define MX1_PUEN 0x40
52 
53 #define MX1_PORT_STRIDE 0x100
54 
55 
56 /*
57  * MUX_ID format defines
58  */
59 #define MX1_MUX_FUNCTION(val) (BIT(0) & val)
60 #define MX1_MUX_GPIO(val) ((BIT(1) & val) >> 1)
61 #define MX1_MUX_DIR(val) ((BIT(2) & val) >> 2)
62 #define MX1_MUX_OCONF(val) (((BIT(4) | BIT(5)) & val) >> 4)
63 #define MX1_MUX_ICONFA(val) (((BIT(8) | BIT(9)) & val) >> 8)
64 #define MX1_MUX_ICONFB(val) (((BIT(10) | BIT(11)) & val) >> 10)
65 
66 
67 /*
68  * IMX1 IOMUXC manages the pins based on ports. Each port has 32 pins. IOMUX
69  * control register are seperated into function, output configuration, input
70  * configuration A, input configuration B, GPIO in use and data direction.
71  *
72  * Those controls that are represented by 1 bit have a direct mapping between
73  * bit position and pin id. If they are represented by 2 bit, the lower 16 pins
74  * are in the first register and the upper 16 pins in the second (next)
75  * register. pin_id is stored in bit (pin_id%16)*2 and the bit above.
76  */
77 
78 /*
79  * Calculates the register offset from a pin_id
80  */
81 static void __iomem *imx1_mem(struct imx1_pinctrl *ipctl, unsigned int pin_id)
82 {
83 	unsigned int port = pin_id / 32;
84 	return ipctl->base + port * MX1_PORT_STRIDE;
85 }
86 
87 /*
88  * Write to a register with 2 bits per pin. The function will automatically
89  * use the next register if the pin is managed in the second register.
90  */
91 static void imx1_write_2bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
92 		u32 value, u32 reg_offset)
93 {
94 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
95 	int offset = (pin_id % 16) * 2; /* offset, regardless of register used */
96 	int mask = ~(0x3 << offset); /* Mask for 2 bits at offset */
97 	u32 old_val;
98 	u32 new_val;
99 
100 	/* Use the next register if the pin's port pin number is >=16 */
101 	if (pin_id % 32 >= 16)
102 		reg += 0x04;
103 
104 	dev_dbg(ipctl->dev, "write: register 0x%p offset %d value 0x%x\n",
105 			reg, offset, value);
106 
107 	/* Get current state of pins */
108 	old_val = readl(reg);
109 	old_val &= mask;
110 
111 	new_val = value & 0x3; /* Make sure value is really 2 bit */
112 	new_val <<= offset;
113 	new_val |= old_val;/* Set new state for pin_id */
114 
115 	writel(new_val, reg);
116 }
117 
118 static void imx1_write_bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
119 		u32 value, u32 reg_offset)
120 {
121 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
122 	int offset = pin_id % 32;
123 	int mask = ~BIT_MASK(offset);
124 	u32 old_val;
125 	u32 new_val;
126 
127 	/* Get current state of pins */
128 	old_val = readl(reg);
129 	old_val &= mask;
130 
131 	new_val = value & 0x1; /* Make sure value is really 1 bit */
132 	new_val <<= offset;
133 	new_val |= old_val;/* Set new state for pin_id */
134 
135 	writel(new_val, reg);
136 }
137 
138 static int imx1_read_2bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
139 		u32 reg_offset)
140 {
141 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
142 	int offset = (pin_id % 16) * 2;
143 
144 	/* Use the next register if the pin's port pin number is >=16 */
145 	if (pin_id % 32 >= 16)
146 		reg += 0x04;
147 
148 	return (readl(reg) & (BIT(offset) | BIT(offset+1))) >> offset;
149 }
150 
151 static int imx1_read_bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
152 		u32 reg_offset)
153 {
154 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
155 	int offset = pin_id % 32;
156 
157 	return !!(readl(reg) & BIT(offset));
158 }
159 
160 static const inline struct imx1_pin_group *imx1_pinctrl_find_group_by_name(
161 				const struct imx1_pinctrl_soc_info *info,
162 				const char *name)
163 {
164 	const struct imx1_pin_group *grp = NULL;
165 	int i;
166 
167 	for (i = 0; i < info->ngroups; i++) {
168 		if (!strcmp(info->groups[i].name, name)) {
169 			grp = &info->groups[i];
170 			break;
171 		}
172 	}
173 
174 	return grp;
175 }
176 
177 static int imx1_get_groups_count(struct pinctrl_dev *pctldev)
178 {
179 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
180 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
181 
182 	return info->ngroups;
183 }
184 
185 static const char *imx1_get_group_name(struct pinctrl_dev *pctldev,
186 				       unsigned selector)
187 {
188 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
189 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
190 
191 	return info->groups[selector].name;
192 }
193 
194 static int imx1_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
195 			       const unsigned int **pins,
196 			       unsigned *npins)
197 {
198 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
199 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
200 
201 	if (selector >= info->ngroups)
202 		return -EINVAL;
203 
204 	*pins = info->groups[selector].pin_ids;
205 	*npins = info->groups[selector].npins;
206 
207 	return 0;
208 }
209 
210 static void imx1_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
211 		   unsigned offset)
212 {
213 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
214 
215 	seq_printf(s, "GPIO %d, function %d, direction %d, oconf %d, iconfa %d, iconfb %d",
216 			imx1_read_bit(ipctl, offset, MX1_GIUS),
217 			imx1_read_bit(ipctl, offset, MX1_GPR),
218 			imx1_read_bit(ipctl, offset, MX1_DDIR),
219 			imx1_read_2bit(ipctl, offset, MX1_OCR),
220 			imx1_read_2bit(ipctl, offset, MX1_ICONFA),
221 			imx1_read_2bit(ipctl, offset, MX1_ICONFB));
222 }
223 
224 static int imx1_dt_node_to_map(struct pinctrl_dev *pctldev,
225 			struct device_node *np,
226 			struct pinctrl_map **map, unsigned *num_maps)
227 {
228 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
229 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
230 	const struct imx1_pin_group *grp;
231 	struct pinctrl_map *new_map;
232 	struct device_node *parent;
233 	int map_num = 1;
234 	int i, j;
235 
236 	/*
237 	 * first find the group of this node and check if we need create
238 	 * config maps for pins
239 	 */
240 	grp = imx1_pinctrl_find_group_by_name(info, np->name);
241 	if (!grp) {
242 		dev_err(info->dev, "unable to find group for node %s\n",
243 			np->name);
244 		return -EINVAL;
245 	}
246 
247 	for (i = 0; i < grp->npins; i++)
248 		map_num++;
249 
250 	new_map = kmalloc(sizeof(struct pinctrl_map) * map_num, GFP_KERNEL);
251 	if (!new_map)
252 		return -ENOMEM;
253 
254 	*map = new_map;
255 	*num_maps = map_num;
256 
257 	/* create mux map */
258 	parent = of_get_parent(np);
259 	if (!parent) {
260 		kfree(new_map);
261 		return -EINVAL;
262 	}
263 	new_map[0].type = PIN_MAP_TYPE_MUX_GROUP;
264 	new_map[0].data.mux.function = parent->name;
265 	new_map[0].data.mux.group = np->name;
266 	of_node_put(parent);
267 
268 	/* create config map */
269 	new_map++;
270 	for (i = j = 0; i < grp->npins; i++) {
271 		new_map[j].type = PIN_MAP_TYPE_CONFIGS_PIN;
272 		new_map[j].data.configs.group_or_pin =
273 				pin_get_name(pctldev, grp->pins[i].pin_id);
274 		new_map[j].data.configs.configs = &grp->pins[i].config;
275 		new_map[j].data.configs.num_configs = 1;
276 		j++;
277 	}
278 
279 	dev_dbg(pctldev->dev, "maps: function %s group %s num %d\n",
280 		(*map)->data.mux.function, (*map)->data.mux.group, map_num);
281 
282 	return 0;
283 }
284 
285 static void imx1_dt_free_map(struct pinctrl_dev *pctldev,
286 				struct pinctrl_map *map, unsigned num_maps)
287 {
288 	kfree(map);
289 }
290 
291 static const struct pinctrl_ops imx1_pctrl_ops = {
292 	.get_groups_count = imx1_get_groups_count,
293 	.get_group_name = imx1_get_group_name,
294 	.get_group_pins = imx1_get_group_pins,
295 	.pin_dbg_show = imx1_pin_dbg_show,
296 	.dt_node_to_map = imx1_dt_node_to_map,
297 	.dt_free_map = imx1_dt_free_map,
298 
299 };
300 
301 static int imx1_pmx_set(struct pinctrl_dev *pctldev, unsigned selector,
302 			unsigned group)
303 {
304 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
305 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
306 	const struct imx1_pin *pins;
307 	unsigned int npins;
308 	int i;
309 
310 	/*
311 	 * Configure the mux mode for each pin in the group for a specific
312 	 * function.
313 	 */
314 	pins = info->groups[group].pins;
315 	npins = info->groups[group].npins;
316 
317 	WARN_ON(!pins || !npins);
318 
319 	dev_dbg(ipctl->dev, "enable function %s group %s\n",
320 		info->functions[selector].name, info->groups[group].name);
321 
322 	for (i = 0; i < npins; i++) {
323 		unsigned int mux = pins[i].mux_id;
324 		unsigned int pin_id = pins[i].pin_id;
325 		unsigned int afunction = MX1_MUX_FUNCTION(mux);
326 		unsigned int gpio_in_use = MX1_MUX_GPIO(mux);
327 		unsigned int direction = MX1_MUX_DIR(mux);
328 		unsigned int gpio_oconf = MX1_MUX_OCONF(mux);
329 		unsigned int gpio_iconfa = MX1_MUX_ICONFA(mux);
330 		unsigned int gpio_iconfb = MX1_MUX_ICONFB(mux);
331 
332 		dev_dbg(pctldev->dev, "%s, pin 0x%x, function %d, gpio %d, direction %d, oconf %d, iconfa %d, iconfb %d\n",
333 				__func__, pin_id, afunction, gpio_in_use,
334 				direction, gpio_oconf, gpio_iconfa,
335 				gpio_iconfb);
336 
337 		imx1_write_bit(ipctl, pin_id, gpio_in_use, MX1_GIUS);
338 		imx1_write_bit(ipctl, pin_id, direction, MX1_DDIR);
339 
340 		if (gpio_in_use) {
341 			imx1_write_2bit(ipctl, pin_id, gpio_oconf, MX1_OCR);
342 			imx1_write_2bit(ipctl, pin_id, gpio_iconfa,
343 					MX1_ICONFA);
344 			imx1_write_2bit(ipctl, pin_id, gpio_iconfb,
345 					MX1_ICONFB);
346 		} else {
347 			imx1_write_bit(ipctl, pin_id, afunction, MX1_GPR);
348 		}
349 	}
350 
351 	return 0;
352 }
353 
354 static int imx1_pmx_get_funcs_count(struct pinctrl_dev *pctldev)
355 {
356 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
357 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
358 
359 	return info->nfunctions;
360 }
361 
362 static const char *imx1_pmx_get_func_name(struct pinctrl_dev *pctldev,
363 					  unsigned selector)
364 {
365 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
366 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
367 
368 	return info->functions[selector].name;
369 }
370 
371 static int imx1_pmx_get_groups(struct pinctrl_dev *pctldev, unsigned selector,
372 			       const char * const **groups,
373 			       unsigned * const num_groups)
374 {
375 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
376 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
377 
378 	*groups = info->functions[selector].groups;
379 	*num_groups = info->functions[selector].num_groups;
380 
381 	return 0;
382 }
383 
384 static const struct pinmux_ops imx1_pmx_ops = {
385 	.get_functions_count = imx1_pmx_get_funcs_count,
386 	.get_function_name = imx1_pmx_get_func_name,
387 	.get_function_groups = imx1_pmx_get_groups,
388 	.set_mux = imx1_pmx_set,
389 };
390 
391 static int imx1_pinconf_get(struct pinctrl_dev *pctldev,
392 			     unsigned pin_id, unsigned long *config)
393 {
394 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
395 
396 	*config = imx1_read_bit(ipctl, pin_id, MX1_PUEN);
397 
398 	return 0;
399 }
400 
401 static int imx1_pinconf_set(struct pinctrl_dev *pctldev,
402 			     unsigned pin_id, unsigned long *configs,
403 			     unsigned num_configs)
404 {
405 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
406 	int i;
407 
408 	for (i = 0; i != num_configs; ++i) {
409 		imx1_write_bit(ipctl, pin_id, configs[i] & 0x01, MX1_PUEN);
410 
411 		dev_dbg(ipctl->dev, "pinconf set pullup pin %s\n",
412 			pin_desc_get(pctldev, pin_id)->name);
413 	}
414 
415 	return 0;
416 }
417 
418 static void imx1_pinconf_dbg_show(struct pinctrl_dev *pctldev,
419 				   struct seq_file *s, unsigned pin_id)
420 {
421 	unsigned long config;
422 
423 	imx1_pinconf_get(pctldev, pin_id, &config);
424 	seq_printf(s, "0x%lx", config);
425 }
426 
427 static void imx1_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
428 					 struct seq_file *s, unsigned group)
429 {
430 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
431 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
432 	struct imx1_pin_group *grp;
433 	unsigned long config;
434 	const char *name;
435 	int i, ret;
436 
437 	if (group > info->ngroups)
438 		return;
439 
440 	seq_puts(s, "\n");
441 	grp = &info->groups[group];
442 	for (i = 0; i < grp->npins; i++) {
443 		name = pin_get_name(pctldev, grp->pins[i].pin_id);
444 		ret = imx1_pinconf_get(pctldev, grp->pins[i].pin_id, &config);
445 		if (ret)
446 			return;
447 		seq_printf(s, "%s: 0x%lx", name, config);
448 	}
449 }
450 
451 static const struct pinconf_ops imx1_pinconf_ops = {
452 	.pin_config_get = imx1_pinconf_get,
453 	.pin_config_set = imx1_pinconf_set,
454 	.pin_config_dbg_show = imx1_pinconf_dbg_show,
455 	.pin_config_group_dbg_show = imx1_pinconf_group_dbg_show,
456 };
457 
458 static struct pinctrl_desc imx1_pinctrl_desc = {
459 	.pctlops = &imx1_pctrl_ops,
460 	.pmxops = &imx1_pmx_ops,
461 	.confops = &imx1_pinconf_ops,
462 	.owner = THIS_MODULE,
463 };
464 
465 static int imx1_pinctrl_parse_groups(struct device_node *np,
466 				    struct imx1_pin_group *grp,
467 				    struct imx1_pinctrl_soc_info *info,
468 				    u32 index)
469 {
470 	int size;
471 	const __be32 *list;
472 	int i;
473 
474 	dev_dbg(info->dev, "group(%d): %s\n", index, np->name);
475 
476 	/* Initialise group */
477 	grp->name = np->name;
478 
479 	/*
480 	 * the binding format is fsl,pins = <PIN MUX_ID CONFIG>
481 	 */
482 	list = of_get_property(np, "fsl,pins", &size);
483 	/* we do not check return since it's safe node passed down */
484 	if (!size || size % 12) {
485 		dev_notice(info->dev, "Not a valid fsl,pins property (%s)\n",
486 				np->name);
487 		return -EINVAL;
488 	}
489 
490 	grp->npins = size / 12;
491 	grp->pins = devm_kzalloc(info->dev,
492 			grp->npins * sizeof(struct imx1_pin), GFP_KERNEL);
493 	grp->pin_ids = devm_kzalloc(info->dev,
494 			grp->npins * sizeof(unsigned int), GFP_KERNEL);
495 
496 	if (!grp->pins || !grp->pin_ids)
497 		return -ENOMEM;
498 
499 	for (i = 0; i < grp->npins; i++) {
500 		grp->pins[i].pin_id = be32_to_cpu(*list++);
501 		grp->pins[i].mux_id = be32_to_cpu(*list++);
502 		grp->pins[i].config = be32_to_cpu(*list++);
503 
504 		grp->pin_ids[i] = grp->pins[i].pin_id;
505 	}
506 
507 	return 0;
508 }
509 
510 static int imx1_pinctrl_parse_functions(struct device_node *np,
511 				       struct imx1_pinctrl_soc_info *info,
512 				       u32 index)
513 {
514 	struct device_node *child;
515 	struct imx1_pmx_func *func;
516 	struct imx1_pin_group *grp;
517 	int ret;
518 	static u32 grp_index;
519 	u32 i = 0;
520 
521 	dev_dbg(info->dev, "parse function(%d): %s\n", index, np->name);
522 
523 	func = &info->functions[index];
524 
525 	/* Initialise function */
526 	func->name = np->name;
527 	func->num_groups = of_get_child_count(np);
528 	if (func->num_groups == 0)
529 		return -EINVAL;
530 
531 	func->groups = devm_kzalloc(info->dev,
532 			func->num_groups * sizeof(char *), GFP_KERNEL);
533 
534 	if (!func->groups)
535 		return -ENOMEM;
536 
537 	for_each_child_of_node(np, child) {
538 		func->groups[i] = child->name;
539 		grp = &info->groups[grp_index++];
540 		ret = imx1_pinctrl_parse_groups(child, grp, info, i++);
541 		if (ret == -ENOMEM) {
542 			of_node_put(child);
543 			return ret;
544 		}
545 	}
546 
547 	return 0;
548 }
549 
550 static int imx1_pinctrl_parse_dt(struct platform_device *pdev,
551 		struct imx1_pinctrl *pctl, struct imx1_pinctrl_soc_info *info)
552 {
553 	struct device_node *np = pdev->dev.of_node;
554 	struct device_node *child;
555 	int ret;
556 	u32 nfuncs = 0;
557 	u32 ngroups = 0;
558 	u32 ifunc = 0;
559 
560 	if (!np)
561 		return -ENODEV;
562 
563 	for_each_child_of_node(np, child) {
564 		++nfuncs;
565 		ngroups += of_get_child_count(child);
566 	}
567 
568 	if (!nfuncs) {
569 		dev_err(&pdev->dev, "No pin functions defined\n");
570 		return -EINVAL;
571 	}
572 
573 	info->nfunctions = nfuncs;
574 	info->functions = devm_kzalloc(&pdev->dev,
575 			nfuncs * sizeof(struct imx1_pmx_func), GFP_KERNEL);
576 
577 	info->ngroups = ngroups;
578 	info->groups = devm_kzalloc(&pdev->dev,
579 			ngroups * sizeof(struct imx1_pin_group), GFP_KERNEL);
580 
581 
582 	if (!info->functions || !info->groups)
583 		return -ENOMEM;
584 
585 	for_each_child_of_node(np, child) {
586 		ret = imx1_pinctrl_parse_functions(child, info, ifunc++);
587 		if (ret == -ENOMEM) {
588 			of_node_put(child);
589 			return -ENOMEM;
590 		}
591 	}
592 
593 	return 0;
594 }
595 
596 int imx1_pinctrl_core_probe(struct platform_device *pdev,
597 		      struct imx1_pinctrl_soc_info *info)
598 {
599 	struct imx1_pinctrl *ipctl;
600 	struct resource *res;
601 	struct pinctrl_desc *pctl_desc;
602 	int ret;
603 
604 	if (!info || !info->pins || !info->npins) {
605 		dev_err(&pdev->dev, "wrong pinctrl info\n");
606 		return -EINVAL;
607 	}
608 	info->dev = &pdev->dev;
609 
610 	/* Create state holders etc for this driver */
611 	ipctl = devm_kzalloc(&pdev->dev, sizeof(*ipctl), GFP_KERNEL);
612 	if (!ipctl)
613 		return -ENOMEM;
614 
615 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
616 	if (!res)
617 		return -ENOENT;
618 
619 	ipctl->base = devm_ioremap_nocache(&pdev->dev, res->start,
620 			resource_size(res));
621 	if (!ipctl->base)
622 		return -ENOMEM;
623 
624 	pctl_desc = &imx1_pinctrl_desc;
625 	pctl_desc->name = dev_name(&pdev->dev);
626 	pctl_desc->pins = info->pins;
627 	pctl_desc->npins = info->npins;
628 
629 	ret = imx1_pinctrl_parse_dt(pdev, ipctl, info);
630 	if (ret) {
631 		dev_err(&pdev->dev, "fail to probe dt properties\n");
632 		return ret;
633 	}
634 
635 	ipctl->info = info;
636 	ipctl->dev = info->dev;
637 	platform_set_drvdata(pdev, ipctl);
638 	ipctl->pctl = devm_pinctrl_register(&pdev->dev, pctl_desc, ipctl);
639 	if (IS_ERR(ipctl->pctl)) {
640 		dev_err(&pdev->dev, "could not register IMX pinctrl driver\n");
641 		return PTR_ERR(ipctl->pctl);
642 	}
643 
644 	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
645 	if (ret) {
646 		pinctrl_unregister(ipctl->pctl);
647 		dev_err(&pdev->dev, "Failed to populate subdevices\n");
648 		return ret;
649 	}
650 
651 	dev_info(&pdev->dev, "initialized IMX pinctrl driver\n");
652 
653 	return 0;
654 }
655