2 * Core driver for the pin muxing portions of the pin control subsystem
4 * Copyright (C) 2011-2012 ST-Ericsson SA
5 * Written on behalf of Linaro for ST-Ericsson
6 * Based on bits of regulator core, gpio core and clk core
8 * Author: Linus Walleij <linus.walleij@linaro.org>
10 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
12 * License terms: GNU General Public License (GPL) version 2
14 #define pr_fmt(fmt) "pinmux core: " fmt
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/device.h>
20 #include <linux/slab.h>
21 #include <linux/radix-tree.h>
22 #include <linux/err.h>
23 #include <linux/list.h>
24 #include <linux/string.h>
25 #include <linux/sysfs.h>
26 #include <linux/debugfs.h>
27 #include <linux/seq_file.h>
28 #include <linux/pinctrl/machine.h>
29 #include <linux/pinctrl/pinmux.h>
33 int pinmux_check_ops(struct pinctrl_dev *pctldev)
35 const struct pinmux_ops *ops = pctldev->desc->pmxops;
37 unsigned selector = 0;
39 /* Check that we implement required operations */
41 !ops->get_functions_count ||
42 !ops->get_function_name ||
43 !ops->get_function_groups ||
45 dev_err(pctldev->dev, "pinmux ops lacks necessary functions\n");
48 /* Check that all functions registered have names */
49 nfuncs = ops->get_functions_count(pctldev);
50 while (selector < nfuncs) {
51 const char *fname = ops->get_function_name(pctldev,
54 dev_err(pctldev->dev, "pinmux ops has no name for function%u\n",
64 int pinmux_validate_map(struct pinctrl_map const *map, int i)
66 if (!map->data.mux.function) {
67 pr_err("failed to register map %s (%d): no function given\n",
76 * pin_request() - request a single pin to be muxed in, typically for GPIO
77 * @pin: the pin number in the global pin space
78 * @owner: a representation of the owner of this pin; typically the device
79 * name that controls its mux function, or the requested GPIO name
80 * @gpio_range: the range matching the GPIO pin if this is a request for a
83 static int pin_request(struct pinctrl_dev *pctldev,
84 int pin, const char *owner,
85 struct pinctrl_gpio_range *gpio_range)
87 struct pin_desc *desc;
88 const struct pinmux_ops *ops = pctldev->desc->pmxops;
91 desc = pin_desc_get(pctldev, pin);
94 "pin %d is not registered so it cannot be requested\n",
99 dev_dbg(pctldev->dev, "request pin %d (%s) for %s\n",
100 pin, desc->name, owner);
103 /* There's no need to support multiple GPIO requests */
104 if (desc->gpio_owner) {
105 dev_err(pctldev->dev,
106 "pin %s already requested by %s; cannot claim for %s\n",
107 desc->name, desc->gpio_owner, owner);
111 desc->gpio_owner = owner;
113 if (desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
114 dev_err(pctldev->dev,
115 "pin %s already requested by %s; cannot claim for %s\n",
116 desc->name, desc->mux_owner, owner);
120 desc->mux_usecount++;
121 if (desc->mux_usecount > 1)
124 desc->mux_owner = owner;
127 /* Let each pin increase references to this module */
128 if (!try_module_get(pctldev->owner)) {
129 dev_err(pctldev->dev,
130 "could not increase module refcount for pin %d\n",
137 * If there is no kind of request function for the pin we just assume
138 * we got it by default and proceed.
140 if (gpio_range && ops->gpio_request_enable)
141 /* This requests and enables a single GPIO pin */
142 status = ops->gpio_request_enable(pctldev, gpio_range, pin);
143 else if (ops->request)
144 status = ops->request(pctldev, pin);
149 dev_err(pctldev->dev, "request() failed for pin %d\n", pin);
150 module_put(pctldev->owner);
156 desc->gpio_owner = NULL;
158 desc->mux_usecount--;
159 if (!desc->mux_usecount)
160 desc->mux_owner = NULL;
165 dev_err(pctldev->dev, "pin-%d (%s) status %d\n",
172 * pin_free() - release a single muxed in pin so something else can be muxed
173 * @pctldev: pin controller device handling this pin
174 * @pin: the pin to free
175 * @gpio_range: the range matching the GPIO pin if this is a request for a
178 * This function returns a pointer to the previous owner. This is used
179 * for callers that dynamically allocate an owner name so it can be freed
180 * once the pin is free. This is done for GPIO request functions.
182 static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
183 struct pinctrl_gpio_range *gpio_range)
185 const struct pinmux_ops *ops = pctldev->desc->pmxops;
186 struct pin_desc *desc;
189 desc = pin_desc_get(pctldev, pin);
191 dev_err(pctldev->dev,
192 "pin is not registered so it cannot be freed\n");
197 desc->mux_usecount--;
198 if (desc->mux_usecount)
203 * If there is no kind of request function for the pin we just assume
204 * we got it by default and proceed.
206 if (gpio_range && ops->gpio_disable_free)
207 ops->gpio_disable_free(pctldev, gpio_range, pin);
209 ops->free(pctldev, pin);
212 owner = desc->gpio_owner;
213 desc->gpio_owner = NULL;
215 owner = desc->mux_owner;
216 desc->mux_owner = NULL;
217 desc->mux_setting = NULL;
220 module_put(pctldev->owner);
226 * pinmux_request_gpio() - request pinmuxing for a GPIO pin
227 * @pctldev: pin controller device affected
228 * @pin: the pin to mux in for GPIO
229 * @range: the applicable GPIO range
231 int pinmux_request_gpio(struct pinctrl_dev *pctldev,
232 struct pinctrl_gpio_range *range,
233 unsigned pin, unsigned gpio)
238 /* Conjure some name stating what chip and pin this is taken by */
239 owner = kasprintf(GFP_KERNEL, "%s:%d", range->name, gpio);
243 ret = pin_request(pctldev, pin, owner, range);
251 * pinmux_free_gpio() - release a pin from GPIO muxing
252 * @pctldev: the pin controller device for the pin
253 * @pin: the affected currently GPIO-muxed in pin
254 * @range: applicable GPIO range
256 void pinmux_free_gpio(struct pinctrl_dev *pctldev, unsigned pin,
257 struct pinctrl_gpio_range *range)
261 owner = pin_free(pctldev, pin, range);
266 * pinmux_gpio_direction() - set the direction of a single muxed-in GPIO pin
267 * @pctldev: the pin controller handling this pin
268 * @range: applicable GPIO range
269 * @pin: the affected GPIO pin in this controller
270 * @input: true if we set the pin as input, false for output
272 int pinmux_gpio_direction(struct pinctrl_dev *pctldev,
273 struct pinctrl_gpio_range *range,
274 unsigned pin, bool input)
276 const struct pinmux_ops *ops;
279 ops = pctldev->desc->pmxops;
281 if (ops->gpio_set_direction)
282 ret = ops->gpio_set_direction(pctldev, range, pin, input);
289 static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
290 const char *function)
292 const struct pinmux_ops *ops = pctldev->desc->pmxops;
293 unsigned nfuncs = ops->get_functions_count(pctldev);
294 unsigned selector = 0;
296 /* See if this pctldev has this function */
297 while (selector < nfuncs) {
298 const char *fname = ops->get_function_name(pctldev,
301 if (!strcmp(function, fname))
307 pr_err("%s does not support function %s\n",
308 pinctrl_dev_get_name(pctldev), function);
312 int pinmux_map_to_setting(struct pinctrl_map const *map,
313 struct pinctrl_setting *setting)
315 struct pinctrl_dev *pctldev = setting->pctldev;
316 const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
317 const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
318 char const * const *groups;
323 const unsigned *pins;
327 dev_err(pctldev->dev, "does not support mux function\n");
331 ret = pinmux_func_name_to_selector(pctldev, map->data.mux.function);
333 dev_err(pctldev->dev, "invalid function %s in map table\n",
334 map->data.mux.function);
337 setting->data.mux.func = ret;
339 ret = pmxops->get_function_groups(pctldev, setting->data.mux.func,
340 &groups, &num_groups);
342 dev_err(pctldev->dev, "can't query groups for function %s\n",
343 map->data.mux.function);
347 dev_err(pctldev->dev,
348 "function %s can't be selected on any group\n",
349 map->data.mux.function);
352 if (map->data.mux.group) {
354 group = map->data.mux.group;
355 for (i = 0; i < num_groups; i++) {
356 if (!strcmp(group, groups[i])) {
362 dev_err(pctldev->dev,
363 "invalid group \"%s\" for function \"%s\"\n",
364 group, map->data.mux.function);
371 ret = pinctrl_get_group_selector(pctldev, group);
373 dev_err(pctldev->dev, "invalid group %s in map table\n",
374 map->data.mux.group);
377 setting->data.mux.group = ret;
379 ret = pctlops->get_group_pins(pctldev, setting->data.mux.group, &pins,
382 dev_err(pctldev->dev,
383 "could not get pins for device %s group selector %d\n",
384 pinctrl_dev_get_name(pctldev), setting->data.mux.group);
388 /* Try to allocate all pins in this group, one by one */
389 for (i = 0; i < num_pins; i++) {
390 ret = pin_request(pctldev, pins[i], map->dev_name, NULL);
392 dev_err(pctldev->dev,
393 "could not request pin %d on device %s\n",
394 pins[i], pinctrl_dev_get_name(pctldev));
395 /* On error release all taken pins */
396 i--; /* this pin just failed */
398 pin_free(pctldev, pins[i], NULL);
406 void pinmux_free_setting(struct pinctrl_setting const *setting)
408 struct pinctrl_dev *pctldev = setting->pctldev;
409 const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
410 const unsigned *pins;
415 ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
418 dev_err(pctldev->dev,
419 "could not get pins for device %s group selector %d\n",
420 pinctrl_dev_get_name(pctldev), setting->data.mux.group);
424 for (i = 0; i < num_pins; i++)
425 pin_free(pctldev, pins[i], NULL);
428 int pinmux_enable_setting(struct pinctrl_setting const *setting)
430 struct pinctrl_dev *pctldev = setting->pctldev;
431 const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
432 const struct pinmux_ops *ops = pctldev->desc->pmxops;
434 const unsigned *pins;
437 struct pin_desc *desc;
439 ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
442 /* errors only affect debug data, so just warn */
443 dev_warn(pctldev->dev,
444 "could not get pins for group selector %d\n",
445 setting->data.mux.group);
449 for (i = 0; i < num_pins; i++) {
450 desc = pin_desc_get(pctldev, pins[i]);
452 dev_warn(pctldev->dev,
453 "could not get pin desc for pin %d\n",
457 desc->mux_setting = &(setting->data.mux);
460 return ops->enable(pctldev, setting->data.mux.func,
461 setting->data.mux.group);
464 void pinmux_disable_setting(struct pinctrl_setting const *setting)
466 struct pinctrl_dev *pctldev = setting->pctldev;
467 const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
468 const struct pinmux_ops *ops = pctldev->desc->pmxops;
470 const unsigned *pins;
473 struct pin_desc *desc;
475 ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
478 /* errors only affect debug data, so just warn */
479 dev_warn(pctldev->dev,
480 "could not get pins for group selector %d\n",
481 setting->data.mux.group);
485 for (i = 0; i < num_pins; i++) {
486 desc = pin_desc_get(pctldev, pins[i]);
488 dev_warn(pctldev->dev,
489 "could not get pin desc for pin %d\n",
493 desc->mux_setting = NULL;
497 ops->disable(pctldev, setting->data.mux.func, setting->data.mux.group);
500 #ifdef CONFIG_DEBUG_FS
502 /* Called from pincontrol core */
503 static int pinmux_functions_show(struct seq_file *s, void *what)
505 struct pinctrl_dev *pctldev = s->private;
506 const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
508 unsigned func_selector = 0;
513 mutex_lock(&pinctrl_mutex);
514 nfuncs = pmxops->get_functions_count(pctldev);
515 while (func_selector < nfuncs) {
516 const char *func = pmxops->get_function_name(pctldev,
518 const char * const *groups;
523 ret = pmxops->get_function_groups(pctldev, func_selector,
524 &groups, &num_groups);
526 seq_printf(s, "function %s: COULD NOT GET GROUPS\n",
529 seq_printf(s, "function: %s, groups = [ ", func);
530 for (i = 0; i < num_groups; i++)
531 seq_printf(s, "%s ", groups[i]);
537 mutex_unlock(&pinctrl_mutex);
542 static int pinmux_pins_show(struct seq_file *s, void *what)
544 struct pinctrl_dev *pctldev = s->private;
545 const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
546 const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
552 seq_puts(s, "Pinmux settings per pin\n");
553 seq_puts(s, "Format: pin (name): mux_owner gpio_owner hog?\n");
555 mutex_lock(&pinctrl_mutex);
557 /* The pin number can be retrived from the pin controller descriptor */
558 for (i = 0; i < pctldev->desc->npins; i++) {
559 struct pin_desc *desc;
562 pin = pctldev->desc->pins[i].number;
563 desc = pin_desc_get(pctldev, pin);
564 /* Skip if we cannot search the pin */
568 if (desc->mux_owner &&
569 !strcmp(desc->mux_owner, pinctrl_dev_get_name(pctldev)))
572 seq_printf(s, "pin %d (%s): %s %s%s", pin,
573 desc->name ? desc->name : "unnamed",
574 desc->mux_owner ? desc->mux_owner
576 desc->gpio_owner ? desc->gpio_owner
577 : "(GPIO UNCLAIMED)",
578 is_hog ? " (HOG)" : "");
580 if (desc->mux_setting)
581 seq_printf(s, " function %s group %s\n",
582 pmxops->get_function_name(pctldev,
583 desc->mux_setting->func),
584 pctlops->get_group_name(pctldev,
585 desc->mux_setting->group));
590 mutex_unlock(&pinctrl_mutex);
595 void pinmux_show_map(struct seq_file *s, struct pinctrl_map const *map)
597 seq_printf(s, "group %s\nfunction %s\n",
598 map->data.mux.group ? map->data.mux.group : "(default)",
599 map->data.mux.function);
602 void pinmux_show_setting(struct seq_file *s,
603 struct pinctrl_setting const *setting)
605 struct pinctrl_dev *pctldev = setting->pctldev;
606 const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
607 const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
609 seq_printf(s, "group: %s (%u) function: %s (%u)\n",
610 pctlops->get_group_name(pctldev, setting->data.mux.group),
611 setting->data.mux.group,
612 pmxops->get_function_name(pctldev, setting->data.mux.func),
613 setting->data.mux.func);
616 static int pinmux_functions_open(struct inode *inode, struct file *file)
618 return single_open(file, pinmux_functions_show, inode->i_private);
621 static int pinmux_pins_open(struct inode *inode, struct file *file)
623 return single_open(file, pinmux_pins_show, inode->i_private);
626 static const struct file_operations pinmux_functions_ops = {
627 .open = pinmux_functions_open,
630 .release = single_release,
633 static const struct file_operations pinmux_pins_ops = {
634 .open = pinmux_pins_open,
637 .release = single_release,
640 void pinmux_init_device_debugfs(struct dentry *devroot,
641 struct pinctrl_dev *pctldev)
643 debugfs_create_file("pinmux-functions", S_IFREG | S_IRUGO,
644 devroot, pctldev, &pinmux_functions_ops);
645 debugfs_create_file("pinmux-pins", S_IFREG | S_IRUGO,
646 devroot, pctldev, &pinmux_pins_ops);
649 #endif /* CONFIG_DEBUG_FS */