1 // SPDX-License-Identifier: GPL-2.0-only
3 * Core driver for the pin muxing portions of the pin control subsystem
5 * Copyright (C) 2011-2012 ST-Ericsson SA
6 * Written on behalf of Linaro for ST-Ericsson
7 * Based on bits of regulator core, gpio core and clk core
9 * Author: Linus Walleij <linus.walleij@linaro.org>
11 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
13 #define pr_fmt(fmt) "pinmux core: " fmt
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/device.h>
19 #include <linux/slab.h>
20 #include <linux/radix-tree.h>
21 #include <linux/err.h>
22 #include <linux/list.h>
23 #include <linux/string.h>
24 #include <linux/debugfs.h>
25 #include <linux/seq_file.h>
26 #include <linux/pinctrl/machine.h>
27 #include <linux/pinctrl/pinmux.h>
31 int pinmux_check_ops(struct pinctrl_dev
*pctldev
)
33 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
35 unsigned selector
= 0;
37 /* Check that we implement required operations */
39 !ops
->get_functions_count
||
40 !ops
->get_function_name
||
41 !ops
->get_function_groups
||
43 dev_err(pctldev
->dev
, "pinmux ops lacks necessary functions\n");
46 /* Check that all functions registered have names */
47 nfuncs
= ops
->get_functions_count(pctldev
);
48 while (selector
< nfuncs
) {
49 const char *fname
= ops
->get_function_name(pctldev
,
52 dev_err(pctldev
->dev
, "pinmux ops has no name for function%u\n",
62 int pinmux_validate_map(const struct pinctrl_map
*map
, int i
)
64 if (!map
->data
.mux
.function
) {
65 pr_err("failed to register map %s (%d): no function given\n",
74 * pinmux_can_be_used_for_gpio() - check if a specific pin
75 * is either muxed to a different function or used as gpio.
77 * @pctldev: the associated pin controller device
78 * @pin: the pin number in the global pin space
80 * Controllers not defined as strict will always return true,
81 * menaning that the gpio can be used.
83 bool pinmux_can_be_used_for_gpio(struct pinctrl_dev
*pctldev
, unsigned pin
)
85 struct pin_desc
*desc
= pin_desc_get(pctldev
, pin
);
86 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
88 /* Can't inspect pin, assume it can be used */
92 if (ops
->strict
&& desc
->mux_usecount
)
95 return !(ops
->strict
&& !!desc
->gpio_owner
);
99 * pin_request() - request a single pin to be muxed in, typically for GPIO
100 * @pctldev: the associated pin controller device
101 * @pin: the pin number in the global pin space
102 * @owner: a representation of the owner of this pin; typically the device
103 * name that controls its mux function, or the requested GPIO name
104 * @gpio_range: the range matching the GPIO pin if this is a request for a
107 static int pin_request(struct pinctrl_dev
*pctldev
,
108 int pin
, const char *owner
,
109 struct pinctrl_gpio_range
*gpio_range
)
111 struct pin_desc
*desc
;
112 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
113 int status
= -EINVAL
;
115 desc
= pin_desc_get(pctldev
, pin
);
117 dev_err(pctldev
->dev
,
118 "pin %d is not registered so it cannot be requested\n",
123 dev_dbg(pctldev
->dev
, "request pin %d (%s) for %s\n",
124 pin
, desc
->name
, owner
);
126 if ((!gpio_range
|| ops
->strict
) &&
127 desc
->mux_usecount
&& strcmp(desc
->mux_owner
, owner
)) {
128 dev_err(pctldev
->dev
,
129 "pin %s already requested by %s; cannot claim for %s\n",
130 desc
->name
, desc
->mux_owner
, owner
);
134 if ((gpio_range
|| ops
->strict
) && desc
->gpio_owner
) {
135 dev_err(pctldev
->dev
,
136 "pin %s already requested by %s; cannot claim for %s\n",
137 desc
->name
, desc
->gpio_owner
, owner
);
142 desc
->gpio_owner
= owner
;
144 desc
->mux_usecount
++;
145 if (desc
->mux_usecount
> 1)
148 desc
->mux_owner
= owner
;
151 /* Let each pin increase references to this module */
152 if (!try_module_get(pctldev
->owner
)) {
153 dev_err(pctldev
->dev
,
154 "could not increase module refcount for pin %d\n",
161 * If there is no kind of request function for the pin we just assume
162 * we got it by default and proceed.
164 if (gpio_range
&& ops
->gpio_request_enable
)
165 /* This requests and enables a single GPIO pin */
166 status
= ops
->gpio_request_enable(pctldev
, gpio_range
, pin
);
167 else if (ops
->request
)
168 status
= ops
->request(pctldev
, pin
);
173 dev_err(pctldev
->dev
, "request() failed for pin %d\n", pin
);
174 module_put(pctldev
->owner
);
180 desc
->gpio_owner
= NULL
;
182 desc
->mux_usecount
--;
183 if (!desc
->mux_usecount
)
184 desc
->mux_owner
= NULL
;
189 dev_err(pctldev
->dev
, "pin-%d (%s) status %d\n",
196 * pin_free() - release a single muxed in pin so something else can be muxed
197 * @pctldev: pin controller device handling this pin
198 * @pin: the pin to free
199 * @gpio_range: the range matching the GPIO pin if this is a request for a
202 * This function returns a pointer to the previous owner. This is used
203 * for callers that dynamically allocate an owner name so it can be freed
204 * once the pin is free. This is done for GPIO request functions.
206 static const char *pin_free(struct pinctrl_dev
*pctldev
, int pin
,
207 struct pinctrl_gpio_range
*gpio_range
)
209 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
210 struct pin_desc
*desc
;
213 desc
= pin_desc_get(pctldev
, pin
);
215 dev_err(pctldev
->dev
,
216 "pin is not registered so it cannot be freed\n");
222 * A pin should not be freed more times than allocated.
224 if (WARN_ON(!desc
->mux_usecount
))
226 desc
->mux_usecount
--;
227 if (desc
->mux_usecount
)
232 * If there is no kind of request function for the pin we just assume
233 * we got it by default and proceed.
235 if (gpio_range
&& ops
->gpio_disable_free
)
236 ops
->gpio_disable_free(pctldev
, gpio_range
, pin
);
238 ops
->free(pctldev
, pin
);
241 owner
= desc
->gpio_owner
;
242 desc
->gpio_owner
= NULL
;
244 owner
= desc
->mux_owner
;
245 desc
->mux_owner
= NULL
;
246 desc
->mux_setting
= NULL
;
249 module_put(pctldev
->owner
);
255 * pinmux_request_gpio() - request pinmuxing for a GPIO pin
256 * @pctldev: pin controller device affected
257 * @pin: the pin to mux in for GPIO
258 * @range: the applicable GPIO range
259 * @gpio: number of requested GPIO
261 int pinmux_request_gpio(struct pinctrl_dev
*pctldev
,
262 struct pinctrl_gpio_range
*range
,
263 unsigned pin
, unsigned gpio
)
268 /* Conjure some name stating what chip and pin this is taken by */
269 owner
= kasprintf(GFP_KERNEL
, "%s:%d", range
->name
, gpio
);
273 ret
= pin_request(pctldev
, pin
, owner
, range
);
281 * pinmux_free_gpio() - release a pin from GPIO muxing
282 * @pctldev: the pin controller device for the pin
283 * @pin: the affected currently GPIO-muxed in pin
284 * @range: applicable GPIO range
286 void pinmux_free_gpio(struct pinctrl_dev
*pctldev
, unsigned pin
,
287 struct pinctrl_gpio_range
*range
)
291 owner
= pin_free(pctldev
, pin
, range
);
296 * pinmux_gpio_direction() - set the direction of a single muxed-in GPIO pin
297 * @pctldev: the pin controller handling this pin
298 * @range: applicable GPIO range
299 * @pin: the affected GPIO pin in this controller
300 * @input: true if we set the pin as input, false for output
302 int pinmux_gpio_direction(struct pinctrl_dev
*pctldev
,
303 struct pinctrl_gpio_range
*range
,
304 unsigned pin
, bool input
)
306 const struct pinmux_ops
*ops
;
309 ops
= pctldev
->desc
->pmxops
;
311 if (ops
->gpio_set_direction
)
312 ret
= ops
->gpio_set_direction(pctldev
, range
, pin
, input
);
319 static int pinmux_func_name_to_selector(struct pinctrl_dev
*pctldev
,
320 const char *function
)
322 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
323 unsigned nfuncs
= ops
->get_functions_count(pctldev
);
324 unsigned selector
= 0;
326 /* See if this pctldev has this function */
327 while (selector
< nfuncs
) {
328 const char *fname
= ops
->get_function_name(pctldev
, selector
);
330 if (!strcmp(function
, fname
))
339 int pinmux_map_to_setting(const struct pinctrl_map
*map
,
340 struct pinctrl_setting
*setting
)
342 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
343 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
344 char const * const *groups
;
350 dev_err(pctldev
->dev
, "does not support mux function\n");
354 ret
= pinmux_func_name_to_selector(pctldev
, map
->data
.mux
.function
);
356 dev_err(pctldev
->dev
, "invalid function %s in map table\n",
357 map
->data
.mux
.function
);
360 setting
->data
.mux
.func
= ret
;
362 ret
= pmxops
->get_function_groups(pctldev
, setting
->data
.mux
.func
,
363 &groups
, &num_groups
);
365 dev_err(pctldev
->dev
, "can't query groups for function %s\n",
366 map
->data
.mux
.function
);
370 dev_err(pctldev
->dev
,
371 "function %s can't be selected on any group\n",
372 map
->data
.mux
.function
);
375 if (map
->data
.mux
.group
) {
376 group
= map
->data
.mux
.group
;
377 ret
= match_string(groups
, num_groups
, group
);
379 dev_err(pctldev
->dev
,
380 "invalid group \"%s\" for function \"%s\"\n",
381 group
, map
->data
.mux
.function
);
388 ret
= pinctrl_get_group_selector(pctldev
, group
);
390 dev_err(pctldev
->dev
, "invalid group %s in map table\n",
391 map
->data
.mux
.group
);
394 setting
->data
.mux
.group
= ret
;
399 void pinmux_free_setting(const struct pinctrl_setting
*setting
)
401 /* This function is currently unused */
404 int pinmux_enable_setting(const struct pinctrl_setting
*setting
)
406 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
407 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
408 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
410 const unsigned *pins
= NULL
;
411 unsigned num_pins
= 0;
413 struct pin_desc
*desc
;
415 if (pctlops
->get_group_pins
)
416 ret
= pctlops
->get_group_pins(pctldev
, setting
->data
.mux
.group
,
422 /* errors only affect debug data, so just warn */
423 gname
= pctlops
->get_group_name(pctldev
,
424 setting
->data
.mux
.group
);
425 dev_warn(pctldev
->dev
,
426 "could not get pins for group %s\n",
431 /* Try to allocate all pins in this group, one by one */
432 for (i
= 0; i
< num_pins
; i
++) {
433 ret
= pin_request(pctldev
, pins
[i
], setting
->dev_name
, NULL
);
438 desc
= pin_desc_get(pctldev
, pins
[i
]);
439 pname
= desc
? desc
->name
: "non-existing";
440 gname
= pctlops
->get_group_name(pctldev
,
441 setting
->data
.mux
.group
);
442 dev_err(pctldev
->dev
,
443 "could not request pin %d (%s) from group %s "
445 pins
[i
], pname
, gname
,
446 pinctrl_dev_get_name(pctldev
));
447 goto err_pin_request
;
451 /* Now that we have acquired the pins, encode the mux setting */
452 for (i
= 0; i
< num_pins
; i
++) {
453 desc
= pin_desc_get(pctldev
, pins
[i
]);
455 dev_warn(pctldev
->dev
,
456 "could not get pin desc for pin %d\n",
460 desc
->mux_setting
= &(setting
->data
.mux
);
463 ret
= ops
->set_mux(pctldev
, setting
->data
.mux
.func
,
464 setting
->data
.mux
.group
);
472 for (i
= 0; i
< num_pins
; i
++) {
473 desc
= pin_desc_get(pctldev
, pins
[i
]);
475 desc
->mux_setting
= NULL
;
478 /* On error release all taken pins */
480 pin_free(pctldev
, pins
[i
], NULL
);
485 void pinmux_disable_setting(const struct pinctrl_setting
*setting
)
487 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
488 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
490 const unsigned *pins
= NULL
;
491 unsigned num_pins
= 0;
493 struct pin_desc
*desc
;
495 if (pctlops
->get_group_pins
)
496 ret
= pctlops
->get_group_pins(pctldev
, setting
->data
.mux
.group
,
501 /* errors only affect debug data, so just warn */
502 gname
= pctlops
->get_group_name(pctldev
,
503 setting
->data
.mux
.group
);
504 dev_warn(pctldev
->dev
,
505 "could not get pins for group %s\n",
510 /* Flag the descs that no setting is active */
511 for (i
= 0; i
< num_pins
; i
++) {
512 desc
= pin_desc_get(pctldev
, pins
[i
]);
514 dev_warn(pctldev
->dev
,
515 "could not get pin desc for pin %d\n",
519 if (desc
->mux_setting
== &(setting
->data
.mux
)) {
520 pin_free(pctldev
, pins
[i
], NULL
);
524 gname
= pctlops
->get_group_name(pctldev
,
525 setting
->data
.mux
.group
);
526 dev_warn(pctldev
->dev
,
527 "not freeing pin %d (%s) as part of "
528 "deactivating group %s - it is already "
529 "used for some other setting",
530 pins
[i
], desc
->name
, gname
);
535 #ifdef CONFIG_DEBUG_FS
537 /* Called from pincontrol core */
538 static int pinmux_functions_show(struct seq_file
*s
, void *what
)
540 struct pinctrl_dev
*pctldev
= s
->private;
541 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
543 unsigned func_selector
= 0;
548 mutex_lock(&pctldev
->mutex
);
549 nfuncs
= pmxops
->get_functions_count(pctldev
);
550 while (func_selector
< nfuncs
) {
551 const char *func
= pmxops
->get_function_name(pctldev
,
553 const char * const *groups
;
558 ret
= pmxops
->get_function_groups(pctldev
, func_selector
,
559 &groups
, &num_groups
);
561 seq_printf(s
, "function %s: COULD NOT GET GROUPS\n",
567 seq_printf(s
, "function: %s, groups = [ ", func
);
568 for (i
= 0; i
< num_groups
; i
++)
569 seq_printf(s
, "%s ", groups
[i
]);
575 mutex_unlock(&pctldev
->mutex
);
580 static int pinmux_pins_show(struct seq_file
*s
, void *what
)
582 struct pinctrl_dev
*pctldev
= s
->private;
583 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
584 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
590 seq_puts(s
, "Pinmux settings per pin\n");
593 "Format: pin (name): mux_owner|gpio_owner (strict) hog?\n");
596 "Format: pin (name): mux_owner gpio_owner hog?\n");
598 mutex_lock(&pctldev
->mutex
);
600 /* The pin number can be retrived from the pin controller descriptor */
601 for (i
= 0; i
< pctldev
->desc
->npins
; i
++) {
602 struct pin_desc
*desc
;
605 pin
= pctldev
->desc
->pins
[i
].number
;
606 desc
= pin_desc_get(pctldev
, pin
);
607 /* Skip if we cannot search the pin */
611 if (desc
->mux_owner
&&
612 !strcmp(desc
->mux_owner
, pinctrl_dev_get_name(pctldev
)))
615 if (pmxops
->strict
) {
617 seq_printf(s
, "pin %d (%s): device %s%s",
618 pin
, desc
->name
, desc
->mux_owner
,
619 is_hog
? " (HOG)" : "");
620 else if (desc
->gpio_owner
)
621 seq_printf(s
, "pin %d (%s): GPIO %s",
622 pin
, desc
->name
, desc
->gpio_owner
);
624 seq_printf(s
, "pin %d (%s): UNCLAIMED",
627 /* For non-strict controllers */
628 seq_printf(s
, "pin %d (%s): %s %s%s", pin
, desc
->name
,
629 desc
->mux_owner
? desc
->mux_owner
631 desc
->gpio_owner
? desc
->gpio_owner
632 : "(GPIO UNCLAIMED)",
633 is_hog
? " (HOG)" : "");
636 /* If mux: print function+group claiming the pin */
637 if (desc
->mux_setting
)
638 seq_printf(s
, " function %s group %s\n",
639 pmxops
->get_function_name(pctldev
,
640 desc
->mux_setting
->func
),
641 pctlops
->get_group_name(pctldev
,
642 desc
->mux_setting
->group
));
647 mutex_unlock(&pctldev
->mutex
);
652 void pinmux_show_map(struct seq_file
*s
, const struct pinctrl_map
*map
)
654 seq_printf(s
, "group %s\nfunction %s\n",
655 map
->data
.mux
.group
? map
->data
.mux
.group
: "(default)",
656 map
->data
.mux
.function
);
659 void pinmux_show_setting(struct seq_file
*s
,
660 const struct pinctrl_setting
*setting
)
662 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
663 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
664 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
666 seq_printf(s
, "group: %s (%u) function: %s (%u)\n",
667 pctlops
->get_group_name(pctldev
, setting
->data
.mux
.group
),
668 setting
->data
.mux
.group
,
669 pmxops
->get_function_name(pctldev
, setting
->data
.mux
.func
),
670 setting
->data
.mux
.func
);
673 DEFINE_SHOW_ATTRIBUTE(pinmux_functions
);
674 DEFINE_SHOW_ATTRIBUTE(pinmux_pins
);
676 void pinmux_init_device_debugfs(struct dentry
*devroot
,
677 struct pinctrl_dev
*pctldev
)
679 debugfs_create_file("pinmux-functions", S_IFREG
| S_IRUGO
,
680 devroot
, pctldev
, &pinmux_functions_fops
);
681 debugfs_create_file("pinmux-pins", S_IFREG
| S_IRUGO
,
682 devroot
, pctldev
, &pinmux_pins_fops
);
685 #endif /* CONFIG_DEBUG_FS */
687 #ifdef CONFIG_GENERIC_PINMUX_FUNCTIONS
690 * pinmux_generic_get_function_count() - returns number of functions
691 * @pctldev: pin controller device
693 int pinmux_generic_get_function_count(struct pinctrl_dev
*pctldev
)
695 return pctldev
->num_functions
;
697 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_count
);
700 * pinmux_generic_get_function_name() - returns the function name
701 * @pctldev: pin controller device
702 * @selector: function number
705 pinmux_generic_get_function_name(struct pinctrl_dev
*pctldev
,
706 unsigned int selector
)
708 struct function_desc
*function
;
710 function
= radix_tree_lookup(&pctldev
->pin_function_tree
,
715 return function
->name
;
717 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_name
);
720 * pinmux_generic_get_function_groups() - gets the function groups
721 * @pctldev: pin controller device
722 * @selector: function number
723 * @groups: array of pin groups
724 * @num_groups: number of pin groups
726 int pinmux_generic_get_function_groups(struct pinctrl_dev
*pctldev
,
727 unsigned int selector
,
728 const char * const **groups
,
729 unsigned * const num_groups
)
731 struct function_desc
*function
;
733 function
= radix_tree_lookup(&pctldev
->pin_function_tree
,
736 dev_err(pctldev
->dev
, "%s could not find function%i\n",
740 *groups
= function
->group_names
;
741 *num_groups
= function
->num_group_names
;
745 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_groups
);
748 * pinmux_generic_get_function() - returns a function based on the number
749 * @pctldev: pin controller device
750 * @selector: function number
752 struct function_desc
*pinmux_generic_get_function(struct pinctrl_dev
*pctldev
,
753 unsigned int selector
)
755 struct function_desc
*function
;
757 function
= radix_tree_lookup(&pctldev
->pin_function_tree
,
764 EXPORT_SYMBOL_GPL(pinmux_generic_get_function
);
767 * pinmux_generic_add_function() - adds a function group
768 * @pctldev: pin controller device
769 * @name: name of the function
770 * @groups: array of pin groups
771 * @num_groups: number of pin groups
772 * @data: pin controller driver specific data
774 int pinmux_generic_add_function(struct pinctrl_dev
*pctldev
,
777 const unsigned int num_groups
,
780 struct function_desc
*function
;
786 selector
= pinmux_func_name_to_selector(pctldev
, name
);
790 selector
= pctldev
->num_functions
;
792 function
= devm_kzalloc(pctldev
->dev
, sizeof(*function
), GFP_KERNEL
);
796 function
->name
= name
;
797 function
->group_names
= groups
;
798 function
->num_group_names
= num_groups
;
799 function
->data
= data
;
801 radix_tree_insert(&pctldev
->pin_function_tree
, selector
, function
);
803 pctldev
->num_functions
++;
807 EXPORT_SYMBOL_GPL(pinmux_generic_add_function
);
810 * pinmux_generic_remove_function() - removes a numbered function
811 * @pctldev: pin controller device
812 * @selector: function number
814 * Note that the caller must take care of locking.
816 int pinmux_generic_remove_function(struct pinctrl_dev
*pctldev
,
817 unsigned int selector
)
819 struct function_desc
*function
;
821 function
= radix_tree_lookup(&pctldev
->pin_function_tree
,
826 radix_tree_delete(&pctldev
->pin_function_tree
, selector
);
827 devm_kfree(pctldev
->dev
, function
);
829 pctldev
->num_functions
--;
833 EXPORT_SYMBOL_GPL(pinmux_generic_remove_function
);
836 * pinmux_generic_free_functions() - removes all functions
837 * @pctldev: pin controller device
839 * Note that the caller must take care of locking. The pinctrl
840 * functions are allocated with devm_kzalloc() so no need to free
843 void pinmux_generic_free_functions(struct pinctrl_dev
*pctldev
)
845 struct radix_tree_iter iter
;
848 radix_tree_for_each_slot(slot
, &pctldev
->pin_function_tree
, &iter
, 0)
849 radix_tree_delete(&pctldev
->pin_function_tree
, iter
.index
);
851 pctldev
->num_functions
= 0;
854 #endif /* CONFIG_GENERIC_PINMUX_FUNCTIONS */