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
);
110 if (ops
->strict
&& desc
->mux_usecount
&&
111 strcmp(desc
->mux_owner
, owner
)) {
112 dev_err(pctldev
->dev
,
113 "pin %s already requested by %s; cannot claim for %s\n",
114 desc
->name
, desc
->mux_owner
, owner
);
118 desc
->gpio_owner
= owner
;
120 if (desc
->mux_usecount
&& strcmp(desc
->mux_owner
, owner
)) {
121 dev_err(pctldev
->dev
,
122 "pin %s already requested by %s; cannot claim for %s\n",
123 desc
->name
, desc
->mux_owner
, owner
);
126 if (ops
->strict
&& desc
->gpio_owner
) {
127 dev_err(pctldev
->dev
,
128 "pin %s already requested by %s; cannot claim for %s\n",
129 desc
->name
, desc
->gpio_owner
, owner
);
133 desc
->mux_usecount
++;
134 if (desc
->mux_usecount
> 1)
137 desc
->mux_owner
= owner
;
140 /* Let each pin increase references to this module */
141 if (!try_module_get(pctldev
->owner
)) {
142 dev_err(pctldev
->dev
,
143 "could not increase module refcount for pin %d\n",
150 * If there is no kind of request function for the pin we just assume
151 * we got it by default and proceed.
153 if (gpio_range
&& ops
->gpio_request_enable
)
154 /* This requests and enables a single GPIO pin */
155 status
= ops
->gpio_request_enable(pctldev
, gpio_range
, pin
);
156 else if (ops
->request
)
157 status
= ops
->request(pctldev
, pin
);
162 dev_err(pctldev
->dev
, "request() failed for pin %d\n", pin
);
163 module_put(pctldev
->owner
);
169 desc
->gpio_owner
= NULL
;
171 desc
->mux_usecount
--;
172 if (!desc
->mux_usecount
)
173 desc
->mux_owner
= NULL
;
178 dev_err(pctldev
->dev
, "pin-%d (%s) status %d\n",
185 * pin_free() - release a single muxed in pin so something else can be muxed
186 * @pctldev: pin controller device handling this pin
187 * @pin: the pin to free
188 * @gpio_range: the range matching the GPIO pin if this is a request for a
191 * This function returns a pointer to the previous owner. This is used
192 * for callers that dynamically allocate an owner name so it can be freed
193 * once the pin is free. This is done for GPIO request functions.
195 static const char *pin_free(struct pinctrl_dev
*pctldev
, int pin
,
196 struct pinctrl_gpio_range
*gpio_range
)
198 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
199 struct pin_desc
*desc
;
202 desc
= pin_desc_get(pctldev
, pin
);
204 dev_err(pctldev
->dev
,
205 "pin is not registered so it cannot be freed\n");
211 * A pin should not be freed more times than allocated.
213 if (WARN_ON(!desc
->mux_usecount
))
215 desc
->mux_usecount
--;
216 if (desc
->mux_usecount
)
221 * If there is no kind of request function for the pin we just assume
222 * we got it by default and proceed.
224 if (gpio_range
&& ops
->gpio_disable_free
)
225 ops
->gpio_disable_free(pctldev
, gpio_range
, pin
);
227 ops
->free(pctldev
, pin
);
230 owner
= desc
->gpio_owner
;
231 desc
->gpio_owner
= NULL
;
233 owner
= desc
->mux_owner
;
234 desc
->mux_owner
= NULL
;
235 desc
->mux_setting
= NULL
;
238 module_put(pctldev
->owner
);
244 * pinmux_request_gpio() - request pinmuxing for a GPIO pin
245 * @pctldev: pin controller device affected
246 * @pin: the pin to mux in for GPIO
247 * @range: the applicable GPIO range
249 int pinmux_request_gpio(struct pinctrl_dev
*pctldev
,
250 struct pinctrl_gpio_range
*range
,
251 unsigned pin
, unsigned gpio
)
256 /* Conjure some name stating what chip and pin this is taken by */
257 owner
= kasprintf(GFP_KERNEL
, "%s:%d", range
->name
, gpio
);
261 ret
= pin_request(pctldev
, pin
, owner
, range
);
269 * pinmux_free_gpio() - release a pin from GPIO muxing
270 * @pctldev: the pin controller device for the pin
271 * @pin: the affected currently GPIO-muxed in pin
272 * @range: applicable GPIO range
274 void pinmux_free_gpio(struct pinctrl_dev
*pctldev
, unsigned pin
,
275 struct pinctrl_gpio_range
*range
)
279 owner
= pin_free(pctldev
, pin
, range
);
284 * pinmux_gpio_direction() - set the direction of a single muxed-in GPIO pin
285 * @pctldev: the pin controller handling this pin
286 * @range: applicable GPIO range
287 * @pin: the affected GPIO pin in this controller
288 * @input: true if we set the pin as input, false for output
290 int pinmux_gpio_direction(struct pinctrl_dev
*pctldev
,
291 struct pinctrl_gpio_range
*range
,
292 unsigned pin
, bool input
)
294 const struct pinmux_ops
*ops
;
297 ops
= pctldev
->desc
->pmxops
;
299 if (ops
->gpio_set_direction
)
300 ret
= ops
->gpio_set_direction(pctldev
, range
, pin
, input
);
307 static int pinmux_func_name_to_selector(struct pinctrl_dev
*pctldev
,
308 const char *function
)
310 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
311 unsigned nfuncs
= ops
->get_functions_count(pctldev
);
312 unsigned selector
= 0;
314 /* See if this pctldev has this function */
315 while (selector
< nfuncs
) {
316 const char *fname
= ops
->get_function_name(pctldev
, selector
);
318 if (!strcmp(function
, fname
))
324 dev_err(pctldev
->dev
, "function '%s' not supported\n", function
);
328 int pinmux_map_to_setting(struct pinctrl_map
const *map
,
329 struct pinctrl_setting
*setting
)
331 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
332 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
333 char const * const *groups
;
339 dev_err(pctldev
->dev
, "does not support mux function\n");
343 ret
= pinmux_func_name_to_selector(pctldev
, map
->data
.mux
.function
);
345 dev_err(pctldev
->dev
, "invalid function %s in map table\n",
346 map
->data
.mux
.function
);
349 setting
->data
.mux
.func
= ret
;
351 ret
= pmxops
->get_function_groups(pctldev
, setting
->data
.mux
.func
,
352 &groups
, &num_groups
);
354 dev_err(pctldev
->dev
, "can't query groups for function %s\n",
355 map
->data
.mux
.function
);
359 dev_err(pctldev
->dev
,
360 "function %s can't be selected on any group\n",
361 map
->data
.mux
.function
);
364 if (map
->data
.mux
.group
) {
365 group
= map
->data
.mux
.group
;
366 ret
= match_string(groups
, num_groups
, group
);
368 dev_err(pctldev
->dev
,
369 "invalid group \"%s\" for function \"%s\"\n",
370 group
, map
->data
.mux
.function
);
377 ret
= pinctrl_get_group_selector(pctldev
, group
);
379 dev_err(pctldev
->dev
, "invalid group %s in map table\n",
380 map
->data
.mux
.group
);
383 setting
->data
.mux
.group
= ret
;
388 void pinmux_free_setting(struct pinctrl_setting
const *setting
)
390 /* This function is currently unused */
393 int pinmux_enable_setting(struct pinctrl_setting
const *setting
)
395 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
396 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
397 const struct pinmux_ops
*ops
= pctldev
->desc
->pmxops
;
399 const unsigned *pins
= NULL
;
400 unsigned num_pins
= 0;
402 struct pin_desc
*desc
;
404 if (pctlops
->get_group_pins
)
405 ret
= pctlops
->get_group_pins(pctldev
, setting
->data
.mux
.group
,
411 /* errors only affect debug data, so just warn */
412 gname
= pctlops
->get_group_name(pctldev
,
413 setting
->data
.mux
.group
);
414 dev_warn(pctldev
->dev
,
415 "could not get pins for group %s\n",
420 /* Try to allocate all pins in this group, one by one */
421 for (i
= 0; i
< num_pins
; i
++) {
422 ret
= pin_request(pctldev
, pins
[i
], setting
->dev_name
, NULL
);
427 desc
= pin_desc_get(pctldev
, pins
[i
]);
428 pname
= desc
? desc
->name
: "non-existing";
429 gname
= pctlops
->get_group_name(pctldev
,
430 setting
->data
.mux
.group
);
431 dev_err(pctldev
->dev
,
432 "could not request pin %d (%s) from group %s "
434 pins
[i
], pname
, gname
,
435 pinctrl_dev_get_name(pctldev
));
436 goto err_pin_request
;
440 /* Now that we have acquired the pins, encode the mux setting */
441 for (i
= 0; i
< num_pins
; i
++) {
442 desc
= pin_desc_get(pctldev
, pins
[i
]);
444 dev_warn(pctldev
->dev
,
445 "could not get pin desc for pin %d\n",
449 desc
->mux_setting
= &(setting
->data
.mux
);
452 ret
= ops
->set_mux(pctldev
, setting
->data
.mux
.func
,
453 setting
->data
.mux
.group
);
461 for (i
= 0; i
< num_pins
; i
++) {
462 desc
= pin_desc_get(pctldev
, pins
[i
]);
464 desc
->mux_setting
= NULL
;
467 /* On error release all taken pins */
469 pin_free(pctldev
, pins
[i
], NULL
);
474 void pinmux_disable_setting(struct pinctrl_setting
const *setting
)
476 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
477 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
479 const unsigned *pins
= NULL
;
480 unsigned num_pins
= 0;
482 struct pin_desc
*desc
;
484 if (pctlops
->get_group_pins
)
485 ret
= pctlops
->get_group_pins(pctldev
, setting
->data
.mux
.group
,
490 /* errors only affect debug data, so just warn */
491 gname
= pctlops
->get_group_name(pctldev
,
492 setting
->data
.mux
.group
);
493 dev_warn(pctldev
->dev
,
494 "could not get pins for group %s\n",
499 /* Flag the descs that no setting is active */
500 for (i
= 0; i
< num_pins
; i
++) {
501 desc
= pin_desc_get(pctldev
, pins
[i
]);
503 dev_warn(pctldev
->dev
,
504 "could not get pin desc for pin %d\n",
508 if (desc
->mux_setting
== &(setting
->data
.mux
)) {
509 desc
->mux_setting
= NULL
;
510 /* And release the pin */
511 pin_free(pctldev
, pins
[i
], NULL
);
515 gname
= pctlops
->get_group_name(pctldev
,
516 setting
->data
.mux
.group
);
517 dev_warn(pctldev
->dev
,
518 "not freeing pin %d (%s) as part of "
519 "deactivating group %s - it is already "
520 "used for some other setting",
521 pins
[i
], desc
->name
, gname
);
526 #ifdef CONFIG_DEBUG_FS
528 /* Called from pincontrol core */
529 static int pinmux_functions_show(struct seq_file
*s
, void *what
)
531 struct pinctrl_dev
*pctldev
= s
->private;
532 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
534 unsigned func_selector
= 0;
539 mutex_lock(&pctldev
->mutex
);
540 nfuncs
= pmxops
->get_functions_count(pctldev
);
541 while (func_selector
< nfuncs
) {
542 const char *func
= pmxops
->get_function_name(pctldev
,
544 const char * const *groups
;
549 ret
= pmxops
->get_function_groups(pctldev
, func_selector
,
550 &groups
, &num_groups
);
552 seq_printf(s
, "function %s: COULD NOT GET GROUPS\n",
558 seq_printf(s
, "function: %s, groups = [ ", func
);
559 for (i
= 0; i
< num_groups
; i
++)
560 seq_printf(s
, "%s ", groups
[i
]);
566 mutex_unlock(&pctldev
->mutex
);
571 static int pinmux_pins_show(struct seq_file
*s
, void *what
)
573 struct pinctrl_dev
*pctldev
= s
->private;
574 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
575 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
581 seq_puts(s
, "Pinmux settings per pin\n");
584 "Format: pin (name): mux_owner|gpio_owner (strict) hog?\n");
587 "Format: pin (name): mux_owner gpio_owner hog?\n");
589 mutex_lock(&pctldev
->mutex
);
591 /* The pin number can be retrived from the pin controller descriptor */
592 for (i
= 0; i
< pctldev
->desc
->npins
; i
++) {
593 struct pin_desc
*desc
;
596 pin
= pctldev
->desc
->pins
[i
].number
;
597 desc
= pin_desc_get(pctldev
, pin
);
598 /* Skip if we cannot search the pin */
602 if (desc
->mux_owner
&&
603 !strcmp(desc
->mux_owner
, pinctrl_dev_get_name(pctldev
)))
606 if (pmxops
->strict
) {
608 seq_printf(s
, "pin %d (%s): device %s%s",
609 pin
, desc
->name
, desc
->mux_owner
,
610 is_hog
? " (HOG)" : "");
611 else if (desc
->gpio_owner
)
612 seq_printf(s
, "pin %d (%s): GPIO %s",
613 pin
, desc
->name
, desc
->gpio_owner
);
615 seq_printf(s
, "pin %d (%s): UNCLAIMED",
618 /* For non-strict controllers */
619 seq_printf(s
, "pin %d (%s): %s %s%s", pin
, desc
->name
,
620 desc
->mux_owner
? desc
->mux_owner
622 desc
->gpio_owner
? desc
->gpio_owner
623 : "(GPIO UNCLAIMED)",
624 is_hog
? " (HOG)" : "");
627 /* If mux: print function+group claiming the pin */
628 if (desc
->mux_setting
)
629 seq_printf(s
, " function %s group %s\n",
630 pmxops
->get_function_name(pctldev
,
631 desc
->mux_setting
->func
),
632 pctlops
->get_group_name(pctldev
,
633 desc
->mux_setting
->group
));
638 mutex_unlock(&pctldev
->mutex
);
643 void pinmux_show_map(struct seq_file
*s
, struct pinctrl_map
const *map
)
645 seq_printf(s
, "group %s\nfunction %s\n",
646 map
->data
.mux
.group
? map
->data
.mux
.group
: "(default)",
647 map
->data
.mux
.function
);
650 void pinmux_show_setting(struct seq_file
*s
,
651 struct pinctrl_setting
const *setting
)
653 struct pinctrl_dev
*pctldev
= setting
->pctldev
;
654 const struct pinmux_ops
*pmxops
= pctldev
->desc
->pmxops
;
655 const struct pinctrl_ops
*pctlops
= pctldev
->desc
->pctlops
;
657 seq_printf(s
, "group: %s (%u) function: %s (%u)\n",
658 pctlops
->get_group_name(pctldev
, setting
->data
.mux
.group
),
659 setting
->data
.mux
.group
,
660 pmxops
->get_function_name(pctldev
, setting
->data
.mux
.func
),
661 setting
->data
.mux
.func
);
664 static int pinmux_functions_open(struct inode
*inode
, struct file
*file
)
666 return single_open(file
, pinmux_functions_show
, inode
->i_private
);
669 static int pinmux_pins_open(struct inode
*inode
, struct file
*file
)
671 return single_open(file
, pinmux_pins_show
, inode
->i_private
);
674 static const struct file_operations pinmux_functions_ops
= {
675 .open
= pinmux_functions_open
,
678 .release
= single_release
,
681 static const struct file_operations pinmux_pins_ops
= {
682 .open
= pinmux_pins_open
,
685 .release
= single_release
,
688 void pinmux_init_device_debugfs(struct dentry
*devroot
,
689 struct pinctrl_dev
*pctldev
)
691 debugfs_create_file("pinmux-functions", S_IFREG
| S_IRUGO
,
692 devroot
, pctldev
, &pinmux_functions_ops
);
693 debugfs_create_file("pinmux-pins", S_IFREG
| S_IRUGO
,
694 devroot
, pctldev
, &pinmux_pins_ops
);
697 #endif /* CONFIG_DEBUG_FS */