xref: /linux/drivers/pinctrl/freescale/pinctrl-imx1-core.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Core driver for the imx pin controller in imx1/21/27
4 //
5 // Copyright (C) 2013 Pengutronix
6 // Author: Markus Pargmann <mpa@pengutronix.de>
7 //
8 // Based on pinctrl-imx.c:
9 //	Author: Dong Aisheng <dong.aisheng@linaro.org>
10 //	Copyright (C) 2012 Freescale Semiconductor, Inc.
11 //	Copyright (C) 2012 Linaro Ltd.
12 
13 #include <linux/bitops.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17 #include <linux/of.h>
18 #include <linux/of_platform.h>
19 #include <linux/platform_device.h>
20 #include <linux/seq_file.h>
21 #include <linux/slab.h>
22 
23 #include <linux/pinctrl/machine.h>
24 #include <linux/pinctrl/pinconf.h>
25 #include <linux/pinctrl/pinctrl.h>
26 #include <linux/pinctrl/pinmux.h>
27 
28 #include "../core.h"
29 #include "pinctrl-imx1.h"
30 
31 struct imx1_pinctrl {
32 	struct device *dev;
33 	struct pinctrl_dev *pctl;
34 	void __iomem *base;
35 	const struct imx1_pinctrl_soc_info *info;
36 };
37 
38 /*
39  * MX1 register offsets
40  */
41 
42 #define MX1_DDIR 0x00
43 #define MX1_OCR 0x04
44 #define MX1_ICONFA 0x0c
45 #define MX1_ICONFB 0x14
46 #define MX1_GIUS 0x20
47 #define MX1_GPR 0x38
48 #define MX1_PUEN 0x40
49 
50 #define MX1_PORT_STRIDE 0x100
51 
52 
53 /*
54  * MUX_ID format defines
55  */
56 #define MX1_MUX_FUNCTION(val) (BIT(0) & val)
57 #define MX1_MUX_GPIO(val) ((BIT(1) & val) >> 1)
58 #define MX1_MUX_DIR(val) ((BIT(2) & val) >> 2)
59 #define MX1_MUX_OCONF(val) (((BIT(4) | BIT(5)) & val) >> 4)
60 #define MX1_MUX_ICONFA(val) (((BIT(8) | BIT(9)) & val) >> 8)
61 #define MX1_MUX_ICONFB(val) (((BIT(10) | BIT(11)) & val) >> 10)
62 
63 
64 /*
65  * IMX1 IOMUXC manages the pins based on ports. Each port has 32 pins. IOMUX
66  * control registers are separated into function, output configuration, input
67  * configuration A, input configuration B, GPIO in use and data direction.
68  *
69  * Those controls that are represented by 1 bit have a direct mapping between
70  * bit position and pin id. If they are represented by 2 bit, the lower 16 pins
71  * are in the first register and the upper 16 pins in the second (next)
72  * register. pin_id is stored in bit (pin_id%16)*2 and the bit above.
73  */
74 
75 /*
76  * Calculates the register offset from a pin_id
77  */
78 static void __iomem *imx1_mem(struct imx1_pinctrl *ipctl, unsigned int pin_id)
79 {
80 	unsigned int port = pin_id / 32;
81 	return ipctl->base + port * MX1_PORT_STRIDE;
82 }
83 
84 /*
85  * Write to a register with 2 bits per pin. The function will automatically
86  * use the next register if the pin is managed in the second register.
87  */
88 static void imx1_write_2bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
89 		u32 value, u32 reg_offset)
90 {
91 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
92 	int offset = (pin_id % 16) * 2; /* offset, regardless of register used */
93 	int mask = ~(0x3 << offset); /* Mask for 2 bits at offset */
94 	u32 old_val;
95 	u32 new_val;
96 
97 	/* Use the next register if the pin's port pin number is >=16 */
98 	if (pin_id % 32 >= 16)
99 		reg += 0x04;
100 
101 	dev_dbg(ipctl->dev, "write: register 0x%p offset %d value 0x%x\n",
102 			reg, offset, value);
103 
104 	/* Get current state of pins */
105 	old_val = readl(reg);
106 	old_val &= mask;
107 
108 	new_val = value & 0x3; /* Make sure value is really 2 bit */
109 	new_val <<= offset;
110 	new_val |= old_val;/* Set new state for pin_id */
111 
112 	writel(new_val, reg);
113 }
114 
115 static void imx1_write_bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
116 		u32 value, u32 reg_offset)
117 {
118 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
119 	int offset = pin_id % 32;
120 	int mask = ~BIT_MASK(offset);
121 	u32 old_val;
122 	u32 new_val;
123 
124 	/* Get current state of pins */
125 	old_val = readl(reg);
126 	old_val &= mask;
127 
128 	new_val = value & 0x1; /* Make sure value is really 1 bit */
129 	new_val <<= offset;
130 	new_val |= old_val;/* Set new state for pin_id */
131 
132 	writel(new_val, reg);
133 }
134 
135 static int imx1_read_2bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
136 		u32 reg_offset)
137 {
138 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
139 	int offset = (pin_id % 16) * 2;
140 
141 	/* Use the next register if the pin's port pin number is >=16 */
142 	if (pin_id % 32 >= 16)
143 		reg += 0x04;
144 
145 	return (readl(reg) & (BIT(offset) | BIT(offset+1))) >> offset;
146 }
147 
148 static int imx1_read_bit(struct imx1_pinctrl *ipctl, unsigned int pin_id,
149 		u32 reg_offset)
150 {
151 	void __iomem *reg = imx1_mem(ipctl, pin_id) + reg_offset;
152 	int offset = pin_id % 32;
153 
154 	return !!(readl(reg) & BIT(offset));
155 }
156 
157 static inline const struct imx1_pin_group *imx1_pinctrl_find_group_by_name(
158 				const struct imx1_pinctrl_soc_info *info,
159 				const char *name)
160 {
161 	const struct imx1_pin_group *grp = NULL;
162 	int i;
163 
164 	for (i = 0; i < info->ngroups; i++) {
165 		if (!strcmp(info->groups[i].name, name)) {
166 			grp = &info->groups[i];
167 			break;
168 		}
169 	}
170 
171 	return grp;
172 }
173 
174 static int imx1_get_groups_count(struct pinctrl_dev *pctldev)
175 {
176 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
177 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
178 
179 	return info->ngroups;
180 }
181 
182 static const char *imx1_get_group_name(struct pinctrl_dev *pctldev,
183 				       unsigned selector)
184 {
185 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
186 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
187 
188 	return info->groups[selector].name;
189 }
190 
191 static int imx1_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
192 			       const unsigned int **pins,
193 			       unsigned *npins)
194 {
195 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
196 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
197 
198 	if (selector >= info->ngroups)
199 		return -EINVAL;
200 
201 	*pins = info->groups[selector].pin_ids;
202 	*npins = info->groups[selector].npins;
203 
204 	return 0;
205 }
206 
207 static void imx1_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
208 		   unsigned offset)
209 {
210 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
211 
212 	seq_printf(s, "GPIO %d, function %d, direction %d, oconf %d, iconfa %d, iconfb %d",
213 			imx1_read_bit(ipctl, offset, MX1_GIUS),
214 			imx1_read_bit(ipctl, offset, MX1_GPR),
215 			imx1_read_bit(ipctl, offset, MX1_DDIR),
216 			imx1_read_2bit(ipctl, offset, MX1_OCR),
217 			imx1_read_2bit(ipctl, offset, MX1_ICONFA),
218 			imx1_read_2bit(ipctl, offset, MX1_ICONFB));
219 }
220 
221 static int imx1_dt_node_to_map(struct pinctrl_dev *pctldev,
222 			struct device_node *np,
223 			struct pinctrl_map **map, unsigned *num_maps)
224 {
225 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
226 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
227 	const struct imx1_pin_group *grp;
228 	struct pinctrl_map *new_map;
229 	struct device_node *parent;
230 	int map_num = 1;
231 	int i, j;
232 
233 	/*
234 	 * first find the group of this node and check if we need create
235 	 * config maps for pins
236 	 */
237 	grp = imx1_pinctrl_find_group_by_name(info, np->name);
238 	if (!grp) {
239 		dev_err(info->dev, "unable to find group for node %pOFn\n",
240 			np);
241 		return -EINVAL;
242 	}
243 
244 	for (i = 0; i < grp->npins; i++)
245 		map_num++;
246 
247 	new_map = kmalloc_array(map_num, sizeof(struct pinctrl_map),
248 				GFP_KERNEL);
249 	if (!new_map)
250 		return -ENOMEM;
251 
252 	*map = new_map;
253 	*num_maps = map_num;
254 
255 	/* create mux map */
256 	parent = of_get_parent(np);
257 	if (!parent) {
258 		kfree(new_map);
259 		return -EINVAL;
260 	}
261 	new_map[0].type = PIN_MAP_TYPE_MUX_GROUP;
262 	new_map[0].data.mux.function = parent->name;
263 	new_map[0].data.mux.group = np->name;
264 	of_node_put(parent);
265 
266 	/* create config map */
267 	new_map++;
268 	for (i = j = 0; i < grp->npins; i++) {
269 		new_map[j].type = PIN_MAP_TYPE_CONFIGS_PIN;
270 		new_map[j].data.configs.group_or_pin =
271 				pin_get_name(pctldev, grp->pins[i].pin_id);
272 		new_map[j].data.configs.configs = &grp->pins[i].config;
273 		new_map[j].data.configs.num_configs = 1;
274 		j++;
275 	}
276 
277 	dev_dbg(pctldev->dev, "maps: function %s group %s num %d\n",
278 		(*map)->data.mux.function, (*map)->data.mux.group, map_num);
279 
280 	return 0;
281 }
282 
283 static void imx1_dt_free_map(struct pinctrl_dev *pctldev,
284 				struct pinctrl_map *map, unsigned num_maps)
285 {
286 	kfree(map);
287 }
288 
289 static const struct pinctrl_ops imx1_pctrl_ops = {
290 	.get_groups_count = imx1_get_groups_count,
291 	.get_group_name = imx1_get_group_name,
292 	.get_group_pins = imx1_get_group_pins,
293 	.pin_dbg_show = imx1_pin_dbg_show,
294 	.dt_node_to_map = imx1_dt_node_to_map,
295 	.dt_free_map = imx1_dt_free_map,
296 };
297 
298 static int imx1_pmx_set(struct pinctrl_dev *pctldev, unsigned selector,
299 			unsigned group)
300 {
301 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
302 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
303 	const struct imx1_pin *pins;
304 	unsigned int npins;
305 	int i;
306 
307 	/*
308 	 * Configure the mux mode for each pin in the group for a specific
309 	 * function.
310 	 */
311 	pins = info->groups[group].pins;
312 	npins = info->groups[group].npins;
313 
314 	WARN_ON(!pins || !npins);
315 
316 	dev_dbg(ipctl->dev, "enable function %s group %s\n",
317 		info->functions[selector].name, info->groups[group].name);
318 
319 	for (i = 0; i < npins; i++) {
320 		unsigned int mux = pins[i].mux_id;
321 		unsigned int pin_id = pins[i].pin_id;
322 		unsigned int afunction = MX1_MUX_FUNCTION(mux);
323 		unsigned int gpio_in_use = MX1_MUX_GPIO(mux);
324 		unsigned int direction = MX1_MUX_DIR(mux);
325 		unsigned int gpio_oconf = MX1_MUX_OCONF(mux);
326 		unsigned int gpio_iconfa = MX1_MUX_ICONFA(mux);
327 		unsigned int gpio_iconfb = MX1_MUX_ICONFB(mux);
328 
329 		dev_dbg(pctldev->dev, "%s, pin 0x%x, function %d, gpio %d, direction %d, oconf %d, iconfa %d, iconfb %d\n",
330 				__func__, pin_id, afunction, gpio_in_use,
331 				direction, gpio_oconf, gpio_iconfa,
332 				gpio_iconfb);
333 
334 		imx1_write_bit(ipctl, pin_id, gpio_in_use, MX1_GIUS);
335 		imx1_write_bit(ipctl, pin_id, direction, MX1_DDIR);
336 
337 		if (gpio_in_use) {
338 			imx1_write_2bit(ipctl, pin_id, gpio_oconf, MX1_OCR);
339 			imx1_write_2bit(ipctl, pin_id, gpio_iconfa,
340 					MX1_ICONFA);
341 			imx1_write_2bit(ipctl, pin_id, gpio_iconfb,
342 					MX1_ICONFB);
343 		} else {
344 			imx1_write_bit(ipctl, pin_id, afunction, MX1_GPR);
345 		}
346 	}
347 
348 	return 0;
349 }
350 
351 static int imx1_pmx_get_funcs_count(struct pinctrl_dev *pctldev)
352 {
353 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
354 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
355 
356 	return info->nfunctions;
357 }
358 
359 static const char *imx1_pmx_get_func_name(struct pinctrl_dev *pctldev,
360 					  unsigned selector)
361 {
362 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
363 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
364 
365 	return info->functions[selector].name;
366 }
367 
368 static int imx1_pmx_get_groups(struct pinctrl_dev *pctldev, unsigned selector,
369 			       const char * const **groups,
370 			       unsigned * const num_groups)
371 {
372 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
373 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
374 
375 	*groups = info->functions[selector].groups;
376 	*num_groups = info->functions[selector].num_groups;
377 
378 	return 0;
379 }
380 
381 static const struct pinmux_ops imx1_pmx_ops = {
382 	.get_functions_count = imx1_pmx_get_funcs_count,
383 	.get_function_name = imx1_pmx_get_func_name,
384 	.get_function_groups = imx1_pmx_get_groups,
385 	.set_mux = imx1_pmx_set,
386 };
387 
388 static int imx1_pinconf_get(struct pinctrl_dev *pctldev,
389 			     unsigned pin_id, unsigned long *config)
390 {
391 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
392 
393 	*config = imx1_read_bit(ipctl, pin_id, MX1_PUEN);
394 
395 	return 0;
396 }
397 
398 static int imx1_pinconf_set(struct pinctrl_dev *pctldev,
399 			     unsigned pin_id, unsigned long *configs,
400 			     unsigned num_configs)
401 {
402 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
403 	int i;
404 
405 	for (i = 0; i != num_configs; ++i) {
406 		imx1_write_bit(ipctl, pin_id, configs[i] & 0x01, MX1_PUEN);
407 
408 		dev_dbg(ipctl->dev, "pinconf set pullup pin %s\n",
409 			pin_desc_get(pctldev, pin_id)->name);
410 	}
411 
412 	return 0;
413 }
414 
415 static void imx1_pinconf_dbg_show(struct pinctrl_dev *pctldev,
416 				   struct seq_file *s, unsigned pin_id)
417 {
418 	unsigned long config;
419 
420 	imx1_pinconf_get(pctldev, pin_id, &config);
421 	seq_printf(s, "0x%lx", config);
422 }
423 
424 static void imx1_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
425 					 struct seq_file *s, unsigned group)
426 {
427 	struct imx1_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
428 	const struct imx1_pinctrl_soc_info *info = ipctl->info;
429 	struct imx1_pin_group *grp;
430 	unsigned long config;
431 	const char *name;
432 	int i, ret;
433 
434 	if (group >= info->ngroups)
435 		return;
436 
437 	seq_puts(s, "\n");
438 	grp = &info->groups[group];
439 	for (i = 0; i < grp->npins; i++) {
440 		name = pin_get_name(pctldev, grp->pins[i].pin_id);
441 		ret = imx1_pinconf_get(pctldev, grp->pins[i].pin_id, &config);
442 		if (ret)
443 			return;
444 		seq_printf(s, "%s: 0x%lx", name, config);
445 	}
446 }
447 
448 static const struct pinconf_ops imx1_pinconf_ops = {
449 	.pin_config_get = imx1_pinconf_get,
450 	.pin_config_set = imx1_pinconf_set,
451 	.pin_config_dbg_show = imx1_pinconf_dbg_show,
452 	.pin_config_group_dbg_show = imx1_pinconf_group_dbg_show,
453 };
454 
455 static struct pinctrl_desc imx1_pinctrl_desc = {
456 	.pctlops = &imx1_pctrl_ops,
457 	.pmxops = &imx1_pmx_ops,
458 	.confops = &imx1_pinconf_ops,
459 	.owner = THIS_MODULE,
460 };
461 
462 static int imx1_pinctrl_parse_groups(struct device_node *np,
463 				    struct imx1_pin_group *grp,
464 				    struct imx1_pinctrl_soc_info *info,
465 				    u32 index)
466 {
467 	int size;
468 	const __be32 *list;
469 	int i;
470 
471 	dev_dbg(info->dev, "group(%d): %pOFn\n", index, np);
472 
473 	/* Initialise group */
474 	grp->name = np->name;
475 
476 	/*
477 	 * the binding format is fsl,pins = <PIN MUX_ID CONFIG>
478 	 */
479 	list = of_get_property(np, "fsl,pins", &size);
480 	/* we do not check return since it's safe node passed down */
481 	if (!size || size % 12) {
482 		dev_notice(info->dev, "Not a valid fsl,pins property (%pOFn)\n",
483 				np);
484 		return -EINVAL;
485 	}
486 
487 	grp->npins = size / 12;
488 	grp->pins = devm_kcalloc(info->dev,
489 			grp->npins, sizeof(struct imx1_pin), GFP_KERNEL);
490 	grp->pin_ids = devm_kcalloc(info->dev,
491 			grp->npins, sizeof(unsigned int), GFP_KERNEL);
492 
493 	if (!grp->pins || !grp->pin_ids)
494 		return -ENOMEM;
495 
496 	for (i = 0; i < grp->npins; i++) {
497 		grp->pins[i].pin_id = be32_to_cpu(*list++);
498 		grp->pins[i].mux_id = be32_to_cpu(*list++);
499 		grp->pins[i].config = be32_to_cpu(*list++);
500 
501 		grp->pin_ids[i] = grp->pins[i].pin_id;
502 	}
503 
504 	return 0;
505 }
506 
507 static int imx1_pinctrl_parse_functions(struct device_node *np,
508 				       struct imx1_pinctrl_soc_info *info,
509 				       u32 index)
510 {
511 	struct imx1_pmx_func *func;
512 	struct imx1_pin_group *grp;
513 	int ret;
514 	static u32 grp_index;
515 	u32 i = 0;
516 
517 	dev_dbg(info->dev, "parse function(%d): %pOFn\n", index, np);
518 
519 	func = &info->functions[index];
520 
521 	/* Initialise function */
522 	func->name = np->name;
523 	func->num_groups = of_get_child_count(np);
524 	if (func->num_groups == 0)
525 		return -EINVAL;
526 
527 	func->groups = devm_kcalloc(info->dev,
528 			func->num_groups, sizeof(char *), GFP_KERNEL);
529 
530 	if (!func->groups)
531 		return -ENOMEM;
532 
533 	for_each_child_of_node_scoped(np, child) {
534 		func->groups[i] = child->name;
535 		grp = &info->groups[grp_index++];
536 		ret = imx1_pinctrl_parse_groups(child, grp, info, i++);
537 		if (ret == -ENOMEM)
538 			return ret;
539 	}
540 
541 	return 0;
542 }
543 
544 static int imx1_pinctrl_parse_dt(struct platform_device *pdev,
545 		struct imx1_pinctrl *pctl, struct imx1_pinctrl_soc_info *info)
546 {
547 	struct device_node *np = pdev->dev.of_node;
548 	int ret;
549 	u32 nfuncs = 0;
550 	u32 ngroups = 0;
551 	u32 ifunc = 0;
552 
553 	if (!np)
554 		return -ENODEV;
555 
556 	for_each_child_of_node_scoped(np, child) {
557 		++nfuncs;
558 		ngroups += of_get_child_count(child);
559 	}
560 
561 	if (!nfuncs) {
562 		dev_err(&pdev->dev, "No pin functions defined\n");
563 		return -EINVAL;
564 	}
565 
566 	info->nfunctions = nfuncs;
567 	info->functions = devm_kcalloc(&pdev->dev,
568 			nfuncs, sizeof(struct imx1_pmx_func), GFP_KERNEL);
569 
570 	info->ngroups = ngroups;
571 	info->groups = devm_kcalloc(&pdev->dev,
572 			ngroups, sizeof(struct imx1_pin_group), GFP_KERNEL);
573 
574 
575 	if (!info->functions || !info->groups)
576 		return -ENOMEM;
577 
578 	for_each_child_of_node_scoped(np, child) {
579 		ret = imx1_pinctrl_parse_functions(child, info, ifunc++);
580 		if (ret == -ENOMEM)
581 			return -ENOMEM;
582 	}
583 
584 	return 0;
585 }
586 
587 int imx1_pinctrl_core_probe(struct platform_device *pdev,
588 		      struct imx1_pinctrl_soc_info *info)
589 {
590 	struct imx1_pinctrl *ipctl;
591 	struct resource *res;
592 	struct pinctrl_desc *pctl_desc;
593 	int ret;
594 
595 	if (!info || !info->pins || !info->npins) {
596 		dev_err(&pdev->dev, "wrong pinctrl info\n");
597 		return -EINVAL;
598 	}
599 	info->dev = &pdev->dev;
600 
601 	/* Create state holders etc for this driver */
602 	ipctl = devm_kzalloc(&pdev->dev, sizeof(*ipctl), GFP_KERNEL);
603 	if (!ipctl)
604 		return -ENOMEM;
605 
606 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
607 	if (!res)
608 		return -ENOENT;
609 
610 	ipctl->base = devm_ioremap(&pdev->dev, res->start,
611 			resource_size(res));
612 	if (!ipctl->base)
613 		return -ENOMEM;
614 
615 	pctl_desc = &imx1_pinctrl_desc;
616 	pctl_desc->name = dev_name(&pdev->dev);
617 	pctl_desc->pins = info->pins;
618 	pctl_desc->npins = info->npins;
619 
620 	ret = imx1_pinctrl_parse_dt(pdev, ipctl, info);
621 	if (ret) {
622 		dev_err(&pdev->dev, "fail to probe dt properties\n");
623 		return ret;
624 	}
625 
626 	ipctl->info = info;
627 	ipctl->dev = info->dev;
628 	platform_set_drvdata(pdev, ipctl);
629 	ipctl->pctl = devm_pinctrl_register(&pdev->dev, pctl_desc, ipctl);
630 	if (IS_ERR(ipctl->pctl)) {
631 		dev_err(&pdev->dev, "could not register IMX pinctrl driver\n");
632 		return PTR_ERR(ipctl->pctl);
633 	}
634 
635 	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
636 	if (ret) {
637 		dev_err(&pdev->dev, "Failed to populate subdevices\n");
638 		return ret;
639 	}
640 
641 	dev_info(&pdev->dev, "initialized IMX pinctrl driver\n");
642 
643 	return 0;
644 }
645