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