xref: /linux/include/linux/gpio/driver.h (revision 0227b49b50276657243e54f5609e65c4f0eaaf4d)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_GPIO_DRIVER_H
3 #define __LINUX_GPIO_DRIVER_H
4 
5 #include <linux/bits.h>
6 #include <linux/cleanup.h>
7 #include <linux/err.h>
8 #include <linux/irqchip/chained_irq.h>
9 #include <linux/irqdomain.h>
10 #include <linux/irqhandler.h>
11 #include <linux/lockdep.h>
12 #include <linux/pinctrl/pinconf-generic.h>
13 #include <linux/pinctrl/pinctrl.h>
14 #include <linux/property.h>
15 #include <linux/spinlock_types.h>
16 #include <linux/types.h>
17 #include <linux/util_macros.h>
18 
19 #ifdef CONFIG_GENERIC_MSI_IRQ
20 #include <asm/msi.h>
21 #endif
22 
23 struct device;
24 struct irq_chip;
25 struct irq_data;
26 struct module;
27 struct of_phandle_args;
28 struct pinctrl_dev;
29 struct seq_file;
30 
31 struct gpio_chip;
32 struct gpio_desc;
33 struct gpio_device;
34 
35 enum gpio_lookup_flags;
36 enum gpiod_flags;
37 
38 union gpio_irq_fwspec {
39 	struct irq_fwspec	fwspec;
40 #ifdef CONFIG_GENERIC_MSI_IRQ
41 	msi_alloc_info_t	msiinfo;
42 #endif
43 };
44 
45 #define GPIO_LINE_DIRECTION_IN	1
46 #define GPIO_LINE_DIRECTION_OUT	0
47 
48 /**
49  * struct gpio_irq_chip - GPIO interrupt controller
50  */
51 struct gpio_irq_chip {
52 	/**
53 	 * @chip:
54 	 *
55 	 * GPIO IRQ chip implementation, provided by GPIO driver.
56 	 */
57 	struct irq_chip *chip;
58 
59 	/**
60 	 * @domain:
61 	 *
62 	 * Interrupt translation domain; responsible for mapping between GPIO
63 	 * hwirq number and Linux IRQ number.
64 	 */
65 	struct irq_domain *domain;
66 
67 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
68 	/**
69 	 * @fwnode:
70 	 *
71 	 * Firmware node corresponding to this gpiochip/irqchip, necessary
72 	 * for hierarchical irqdomain support.
73 	 */
74 	struct fwnode_handle *fwnode;
75 
76 	/**
77 	 * @parent_domain:
78 	 *
79 	 * If non-NULL, will be set as the parent of this GPIO interrupt
80 	 * controller's IRQ domain to establish a hierarchical interrupt
81 	 * domain. The presence of this will activate the hierarchical
82 	 * interrupt support.
83 	 */
84 	struct irq_domain *parent_domain;
85 
86 	/**
87 	 * @child_to_parent_hwirq:
88 	 *
89 	 * This callback translates a child hardware IRQ offset to a parent
90 	 * hardware IRQ offset on a hierarchical interrupt chip. The child
91 	 * hardware IRQs correspond to the GPIO index 0..ngpio-1 (see the
92 	 * ngpio field of struct gpio_chip) and the corresponding parent
93 	 * hardware IRQ and type (such as IRQ_TYPE_*) shall be returned by
94 	 * the driver. The driver can calculate this from an offset or using
95 	 * a lookup table or whatever method is best for this chip. Return
96 	 * 0 on successful translation in the driver.
97 	 *
98 	 * If some ranges of hardware IRQs do not have a corresponding parent
99 	 * HWIRQ, return -EINVAL, but also make sure to fill in @valid_mask and
100 	 * @need_valid_mask to make these GPIO lines unavailable for
101 	 * translation.
102 	 */
103 	int (*child_to_parent_hwirq)(struct gpio_chip *gc,
104 				     unsigned int child_hwirq,
105 				     unsigned int child_type,
106 				     unsigned int *parent_hwirq,
107 				     unsigned int *parent_type);
108 
109 	/**
110 	 * @populate_parent_alloc_arg :
111 	 *
112 	 * This optional callback allocates and populates the specific struct
113 	 * for the parent's IRQ domain. If this is not specified, then
114 	 * &gpiochip_populate_parent_fwspec_twocell will be used. A four-cell
115 	 * variant named &gpiochip_populate_parent_fwspec_fourcell is also
116 	 * available.
117 	 */
118 	int (*populate_parent_alloc_arg)(struct gpio_chip *gc,
119 					 union gpio_irq_fwspec *fwspec,
120 					 unsigned int parent_hwirq,
121 					 unsigned int parent_type);
122 
123 	/**
124 	 * @child_offset_to_irq:
125 	 *
126 	 * This optional callback is used to translate the child's GPIO line
127 	 * offset on the GPIO chip to an IRQ number for the GPIO to_irq()
128 	 * callback. If this is not specified, then a default callback will be
129 	 * provided that returns the line offset.
130 	 */
131 	unsigned int (*child_offset_to_irq)(struct gpio_chip *gc,
132 					    unsigned int pin);
133 
134 	/**
135 	 * @child_irq_domain_ops:
136 	 *
137 	 * The IRQ domain operations that will be used for this GPIO IRQ
138 	 * chip. If no operations are provided, then default callbacks will
139 	 * be populated to setup the IRQ hierarchy. Some drivers need to
140 	 * supply their own translate function.
141 	 */
142 	struct irq_domain_ops child_irq_domain_ops;
143 #endif
144 
145 	/**
146 	 * @handler:
147 	 *
148 	 * The IRQ handler to use (often a predefined IRQ core function) for
149 	 * GPIO IRQs, provided by GPIO driver.
150 	 */
151 	irq_flow_handler_t handler;
152 
153 	/**
154 	 * @default_type:
155 	 *
156 	 * Default IRQ triggering type applied during GPIO driver
157 	 * initialization, provided by GPIO driver.
158 	 */
159 	unsigned int default_type;
160 
161 	/**
162 	 * @lock_key:
163 	 *
164 	 * Per GPIO IRQ chip lockdep class for IRQ lock.
165 	 */
166 	struct lock_class_key *lock_key;
167 
168 	/**
169 	 * @request_key:
170 	 *
171 	 * Per GPIO IRQ chip lockdep class for IRQ request.
172 	 */
173 	struct lock_class_key *request_key;
174 
175 	/**
176 	 * @parent_handler:
177 	 *
178 	 * The interrupt handler for the GPIO chip's parent interrupts, may be
179 	 * NULL if the parent interrupts are nested rather than cascaded.
180 	 */
181 	irq_flow_handler_t parent_handler;
182 
183 	union {
184 		/**
185 		 * @parent_handler_data:
186 		 *
187 		 * If @per_parent_data is false, @parent_handler_data is a
188 		 * single pointer used as the data associated with every
189 		 * parent interrupt.
190 		 */
191 		void *parent_handler_data;
192 
193 		/**
194 		 * @parent_handler_data_array:
195 		 *
196 		 * If @per_parent_data is true, @parent_handler_data_array is
197 		 * an array of @num_parents pointers, and is used to associate
198 		 * different data for each parent. This cannot be NULL if
199 		 * @per_parent_data is true.
200 		 */
201 		void **parent_handler_data_array;
202 	};
203 
204 	/**
205 	 * @num_parents:
206 	 *
207 	 * The number of interrupt parents of a GPIO chip.
208 	 */
209 	unsigned int num_parents;
210 
211 	/**
212 	 * @parents:
213 	 *
214 	 * A list of interrupt parents of a GPIO chip. This is owned by the
215 	 * driver, so the core will only reference this list, not modify it.
216 	 */
217 	unsigned int *parents;
218 
219 	/**
220 	 * @map:
221 	 *
222 	 * A list of interrupt parents for each line of a GPIO chip.
223 	 */
224 	unsigned int *map;
225 
226 	/**
227 	 * @threaded:
228 	 *
229 	 * True if set the interrupt handling uses nested threads.
230 	 */
231 	bool threaded;
232 
233 	/**
234 	 * @per_parent_data:
235 	 *
236 	 * True if parent_handler_data_array describes a @num_parents
237 	 * sized array to be used as parent data.
238 	 */
239 	bool per_parent_data;
240 
241 	/**
242 	 * @initialized:
243 	 *
244 	 * Flag to track GPIO chip irq member's initialization.
245 	 * This flag will make sure GPIO chip irq members are not used
246 	 * before they are initialized.
247 	 */
248 	bool initialized;
249 
250 	/**
251 	 * @domain_is_allocated_externally:
252 	 *
253 	 * True it the irq_domain was allocated outside of gpiolib, in which
254 	 * case gpiolib won't free the irq_domain itself.
255 	 */
256 	bool domain_is_allocated_externally;
257 
258 	/**
259 	 * @init_hw: optional routine to initialize hardware before
260 	 * an IRQ chip will be added. This is quite useful when
261 	 * a particular driver wants to clear IRQ related registers
262 	 * in order to avoid undesired events.
263 	 */
264 	int (*init_hw)(struct gpio_chip *gc);
265 
266 	/**
267 	 * @init_valid_mask: optional routine to initialize @valid_mask, to be
268 	 * used if not all GPIO lines are valid interrupts. Sometimes some
269 	 * lines just cannot fire interrupts, and this routine, when defined,
270 	 * is passed a bitmap in "valid_mask" and it will have ngpios
271 	 * bits from 0..(ngpios-1) set to "1" as in valid. The callback can
272 	 * then directly set some bits to "0" if they cannot be used for
273 	 * interrupts.
274 	 */
275 	void (*init_valid_mask)(struct gpio_chip *gc,
276 				unsigned long *valid_mask,
277 				unsigned int ngpios);
278 
279 	/**
280 	 * @valid_mask:
281 	 *
282 	 * If not %NULL, holds bitmask of GPIOs which are valid to be included
283 	 * in IRQ domain of the chip.
284 	 */
285 	unsigned long *valid_mask;
286 
287 	/**
288 	 * @first:
289 	 *
290 	 * Required for static IRQ allocation. If set,
291 	 * irq_domain_create_simple() will allocate and map all IRQs
292 	 * during initialization.
293 	 */
294 	unsigned int first;
295 
296 	/**
297 	 * @irq_enable:
298 	 *
299 	 * Store old irq_chip irq_enable callback
300 	 */
301 	void		(*irq_enable)(struct irq_data *data);
302 
303 	/**
304 	 * @irq_disable:
305 	 *
306 	 * Store old irq_chip irq_disable callback
307 	 */
308 	void		(*irq_disable)(struct irq_data *data);
309 	/**
310 	 * @irq_unmask:
311 	 *
312 	 * Store old irq_chip irq_unmask callback
313 	 */
314 	void		(*irq_unmask)(struct irq_data *data);
315 
316 	/**
317 	 * @irq_mask:
318 	 *
319 	 * Store old irq_chip irq_mask callback
320 	 */
321 	void		(*irq_mask)(struct irq_data *data);
322 };
323 
324 /**
325  * struct gpio_chip - abstract a GPIO controller
326  * @label: a functional name for the GPIO device, such as a part
327  *	number or the name of the SoC IP-block implementing it.
328  * @gpiodev: the internal state holder, opaque struct
329  * @parent: optional parent device providing the GPIOs
330  * @fwnode: optional fwnode providing this controller's properties
331  * @owner: helps prevent removal of modules exporting active GPIOs
332  * @request: optional hook for chip-specific activation, such as
333  *	enabling module power and clock; may sleep; must return 0 on success
334  *	or negative error number on failure
335  * @free: optional hook for chip-specific deactivation, such as
336  *	disabling module power and clock; may sleep
337  * @get_direction: returns direction for signal "offset", 0=out, 1=in,
338  *	(same as GPIO_LINE_DIRECTION_OUT / GPIO_LINE_DIRECTION_IN),
339  *	or negative error. It is recommended to always implement this
340  *	function, even on input-only or output-only gpio chips.
341  * @direction_input: configures signal "offset" as input, returns 0 on success
342  *	or a negative error number. This can be omitted on input-only or
343  *	output-only gpio chips.
344  * @direction_output: configures signal "offset" as output, returns 0 on
345  *	success or a negative error number. This can be omitted on input-only
346  *	or output-only gpio chips.
347  * @get: returns value for signal "offset", 0=low, 1=high, or negative error
348  * @get_multiple: reads values for multiple signals defined by "mask" and
349  *	stores them in "bits", returns 0 on success or negative error
350  * @set: assigns output value for signal "offset", returns 0 on success or
351  *       negative error value
352  * @set_multiple: assigns output values for multiple signals defined by
353  *                "mask", returns 0 on success or negative error value
354  * @set_config: optional hook for all kinds of settings. Uses the same
355  *	packed config format as generic pinconf. Must return 0 on success and
356  *	a negative error number on failure.
357  * @to_irq: optional hook supporting non-static gpiod_to_irq() mappings;
358  *	implementation may not sleep
359  * @dbg_show: optional routine to show contents in debugfs; default code
360  *	will be used when this is omitted, but custom code can show extra
361  *	state (such as pullup/pulldown configuration).
362  * @init_valid_mask: optional routine to initialize @valid_mask, to be used if
363  *	not all GPIOs are valid.
364  * @add_pin_ranges: optional routine to initialize pin ranges, to be used when
365  *	requires special mapping of the pins that provides GPIO functionality.
366  *	It is called after adding GPIO chip and before adding IRQ chip.
367  * @en_hw_timestamp: Dependent on GPIO chip, an optional routine to
368  *	enable hardware timestamp.
369  * @dis_hw_timestamp: Dependent on GPIO chip, an optional routine to
370  *	disable hardware timestamp.
371  * @base: identifies the first GPIO number handled by this chip;
372  *	or, if negative during registration, requests dynamic ID allocation.
373  *	DEPRECATION: providing anything non-negative and nailing the base
374  *	offset of GPIO chips is deprecated. Please pass -1 as base to
375  *	let gpiolib select the chip base in all possible cases. We want to
376  *	get rid of the static GPIO number space in the long run.
377  * @ngpio: the number of GPIOs handled by this controller; the last GPIO
378  *	handled is (base + ngpio - 1).
379  * @offset: when multiple gpio chips belong to the same device this
380  *	can be used as offset within the device so friendly names can
381  *	be properly assigned.
382  * @names: if set, must be an array of strings to use as alternative
383  *      names for the GPIOs in this chip. Any entry in the array
384  *      may be NULL if there is no alias for the GPIO, however the
385  *      array must be @ngpio entries long.
386  * @can_sleep: flag must be set iff get()/set() methods sleep, as they
387  *	must while accessing GPIO expander chips over I2C or SPI. This
388  *	implies that if the chip supports IRQs, these IRQs need to be threaded
389  *	as the chip access may sleep when e.g. reading out the IRQ status
390  *	registers.
391  * @read_reg: reader function for generic GPIO
392  * @write_reg: writer function for generic GPIO
393  * @be_bits: if the generic GPIO has big endian bit order (bit 31 is representing
394  *	line 0, bit 30 is line 1 ... bit 0 is line 31) this is set to true by the
395  *	generic GPIO core. It is for internal housekeeping only.
396  * @reg_dat: data (in) register for generic GPIO
397  * @reg_set: output set register (out=high) for generic GPIO
398  * @reg_clr: output clear register (out=low) for generic GPIO
399  * @reg_dir_out: direction out setting register for generic GPIO
400  * @reg_dir_in: direction in setting register for generic GPIO
401  * @bgpio_dir_unreadable: indicates that the direction register(s) cannot
402  *	be read and we need to rely on out internal state tracking.
403  * @bgpio_pinctrl: the generic GPIO uses a pin control backend.
404  * @bgpio_bits: number of register bits used for a generic GPIO i.e.
405  *	<register width> * 8
406  * @bgpio_lock: used to lock chip->bgpio_data. Also, this is needed to keep
407  *	shadowed and real data registers writes together.
408  * @bgpio_data:	shadowed data register for generic GPIO to clear/set bits
409  *	safely.
410  * @bgpio_dir: shadowed direction register for generic GPIO to clear/set
411  *	direction safely. A "1" in this word means the line is set as
412  *	output.
413  *
414  * A gpio_chip can help platforms abstract various sources of GPIOs so
415  * they can all be accessed through a common programming interface.
416  * Example sources would be SOC controllers, FPGAs, multifunction
417  * chips, dedicated GPIO expanders, and so on.
418  *
419  * Each chip controls a number of signals, identified in method calls
420  * by "offset" values in the range 0..(@ngpio - 1).  When those signals
421  * are referenced through calls like gpio_get_value(gpio), the offset
422  * is calculated by subtracting @base from the gpio number.
423  */
424 struct gpio_chip {
425 	const char		*label;
426 	struct gpio_device	*gpiodev;
427 	struct device		*parent;
428 	struct fwnode_handle	*fwnode;
429 	struct module		*owner;
430 
431 	int			(*request)(struct gpio_chip *gc,
432 						unsigned int offset);
433 	void			(*free)(struct gpio_chip *gc,
434 						unsigned int offset);
435 	int			(*get_direction)(struct gpio_chip *gc,
436 						unsigned int offset);
437 	int			(*direction_input)(struct gpio_chip *gc,
438 						unsigned int offset);
439 	int			(*direction_output)(struct gpio_chip *gc,
440 						unsigned int offset, int value);
441 	int			(*get)(struct gpio_chip *gc,
442 						unsigned int offset);
443 	int			(*get_multiple)(struct gpio_chip *gc,
444 						unsigned long *mask,
445 						unsigned long *bits);
446 	int			(*set)(struct gpio_chip *gc,
447 				       unsigned int offset, int value);
448 	int			(*set_multiple)(struct gpio_chip *gc,
449 						unsigned long *mask,
450 						unsigned long *bits);
451 	int			(*set_config)(struct gpio_chip *gc,
452 					      unsigned int offset,
453 					      unsigned long config);
454 	int			(*to_irq)(struct gpio_chip *gc,
455 						unsigned int offset);
456 
457 	void			(*dbg_show)(struct seq_file *s,
458 						struct gpio_chip *gc);
459 
460 	int			(*init_valid_mask)(struct gpio_chip *gc,
461 						   unsigned long *valid_mask,
462 						   unsigned int ngpios);
463 
464 	int			(*add_pin_ranges)(struct gpio_chip *gc);
465 
466 	int			(*en_hw_timestamp)(struct gpio_chip *gc,
467 						   u32 offset,
468 						   unsigned long flags);
469 	int			(*dis_hw_timestamp)(struct gpio_chip *gc,
470 						    u32 offset,
471 						    unsigned long flags);
472 	int			base;
473 	u16			ngpio;
474 	u16			offset;
475 	const char		*const *names;
476 	bool			can_sleep;
477 
478 #if IS_ENABLED(CONFIG_GPIO_GENERIC)
479 	unsigned long (*read_reg)(void __iomem *reg);
480 	void (*write_reg)(void __iomem *reg, unsigned long data);
481 	bool be_bits;
482 	void __iomem *reg_dat;
483 	void __iomem *reg_set;
484 	void __iomem *reg_clr;
485 	void __iomem *reg_dir_out;
486 	void __iomem *reg_dir_in;
487 	bool bgpio_dir_unreadable;
488 	bool bgpio_pinctrl;
489 	int bgpio_bits;
490 	raw_spinlock_t bgpio_lock;
491 	unsigned long bgpio_data;
492 	unsigned long bgpio_dir;
493 #endif /* CONFIG_GPIO_GENERIC */
494 
495 #ifdef CONFIG_GPIOLIB_IRQCHIP
496 	/*
497 	 * With CONFIG_GPIOLIB_IRQCHIP we get an irqchip inside the gpiolib
498 	 * to handle IRQs for most practical cases.
499 	 */
500 
501 	/**
502 	 * @irq:
503 	 *
504 	 * Integrates interrupt chip functionality with the GPIO chip. Can be
505 	 * used to handle IRQs for most practical cases.
506 	 */
507 	struct gpio_irq_chip irq;
508 #endif /* CONFIG_GPIOLIB_IRQCHIP */
509 
510 #if defined(CONFIG_OF_GPIO)
511 	/*
512 	 * If CONFIG_OF_GPIO is enabled, then all GPIO controllers described in
513 	 * the device tree automatically may have an OF translation
514 	 */
515 
516 	/**
517 	 * @of_gpio_n_cells:
518 	 *
519 	 * Number of cells used to form the GPIO specifier. The standard is 2
520 	 * cells:
521 	 *
522 	 * gpios = <&gpio offset flags>;
523 	 *
524 	 * some complex GPIO controllers instantiate more than one chip per
525 	 * device tree node and have 3 cells:
526 	 *
527 	 * gpios = <&gpio instance offset flags>;
528 	 *
529 	 * Legacy GPIO controllers may even have 1 cell:
530 	 *
531 	 * gpios = <&gpio offset>;
532 	 */
533 	unsigned int of_gpio_n_cells;
534 
535 	/**
536 	 * @of_node_instance_match:
537 	 *
538 	 * Determine if a chip is the right instance. Must be implemented by
539 	 * any driver using more than one gpio_chip per device tree node.
540 	 * Returns true if gc is the instance indicated by i (which is the
541 	 * first cell in the phandles for GPIO lines and gpio-ranges).
542 	 */
543 	bool (*of_node_instance_match)(struct gpio_chip *gc, unsigned int i);
544 
545 	/**
546 	 * @of_xlate:
547 	 *
548 	 * Callback to translate a device tree GPIO specifier into a chip-
549 	 * relative GPIO number and flags.
550 	 */
551 	int (*of_xlate)(struct gpio_chip *gc,
552 			const struct of_phandle_args *gpiospec, u32 *flags);
553 #endif /* CONFIG_OF_GPIO */
554 };
555 
556 char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset);
557 
558 
559 struct _gpiochip_for_each_data {
560 	const char **label;
561 	unsigned int *i;
562 };
563 
564 DEFINE_CLASS(_gpiochip_for_each_data,
565 	     struct _gpiochip_for_each_data,
566 	     if (*_T.label) kfree(*_T.label),
567 	     ({
568 		struct _gpiochip_for_each_data _data = { label, i };
569 		*_data.i = 0;
570 		_data;
571 	     }),
572 	     const char **label, int *i)
573 
574 /**
575  * for_each_hwgpio_in_range - Iterates over all GPIOs in a given range
576  * @_chip: Chip to iterate over.
577  * @_i: Loop counter.
578  * @_base: First GPIO in the ranger.
579  * @_size: Amount of GPIOs to check starting from @base.
580  * @_label: Place to store the address of the label if the GPIO is requested.
581  *          Set to NULL for unused GPIOs.
582  */
583 #define for_each_hwgpio_in_range(_chip, _i, _base, _size, _label)			\
584 	for (CLASS(_gpiochip_for_each_data, _data)(&_label, &_i);			\
585 	     _i < _size;								\
586 	     _i++, kfree(_label), _label = NULL)					\
587 		for_each_if(!IS_ERR(_label = gpiochip_dup_line_label(_chip, _base + _i)))
588 
589 /**
590  * for_each_hwgpio - Iterates over all GPIOs for given chip.
591  * @_chip: Chip to iterate over.
592  * @_i: Loop counter.
593  * @_label: Place to store the address of the label if the GPIO is requested.
594  *          Set to NULL for unused GPIOs.
595  */
596 #define for_each_hwgpio(_chip, _i, _label)						\
597 	for_each_hwgpio_in_range(_chip, _i, 0, _chip->ngpio, _label)
598 
599 /**
600  * for_each_requested_gpio_in_range - iterates over requested GPIOs in a given range
601  * @_chip:	the chip to query
602  * @_i:		loop variable
603  * @_base:	first GPIO in the range
604  * @_size:	amount of GPIOs to check starting from @base
605  * @_label:	label of current GPIO
606  */
607 #define for_each_requested_gpio_in_range(_chip, _i, _base, _size, _label)		\
608 	for_each_hwgpio_in_range(_chip, _i, _base, _size, _label)			\
609 		for_each_if(_label)
610 
611 /* Iterates over all requested GPIO of the given @chip */
612 #define for_each_requested_gpio(chip, i, label)						\
613 	for_each_requested_gpio_in_range(chip, i, 0, chip->ngpio, label)
614 
615 /* add/remove chips */
616 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
617 			       struct lock_class_key *lock_key,
618 			       struct lock_class_key *request_key);
619 
620 /**
621  * gpiochip_add_data() - register a gpio_chip
622  * @gc: the chip to register, with gc->base initialized
623  * @data: driver-private data associated with this chip
624  *
625  * Context: potentially before irqs will work
626  *
627  * When gpiochip_add_data() is called very early during boot, so that GPIOs
628  * can be freely used, the gc->parent device must be registered before
629  * the gpio framework's arch_initcall().  Otherwise sysfs initialization
630  * for GPIOs will fail rudely.
631  *
632  * gpiochip_add_data() must only be called after gpiolib initialization,
633  * i.e. after core_initcall().
634  *
635  * If gc->base is negative, this requests dynamic assignment of
636  * a range of valid GPIOs.
637  *
638  * Returns:
639  * A negative errno if the chip can't be registered, such as because the
640  * gc->base is invalid or already associated with a different chip.
641  * Otherwise it returns zero as a success code.
642  */
643 #ifdef CONFIG_LOCKDEP
644 #define gpiochip_add_data(gc, data) ({		\
645 		static struct lock_class_key lock_key;	\
646 		static struct lock_class_key request_key;	  \
647 		gpiochip_add_data_with_key(gc, data, &lock_key, \
648 					   &request_key);	  \
649 	})
650 #define devm_gpiochip_add_data(dev, gc, data) ({ \
651 		static struct lock_class_key lock_key;	\
652 		static struct lock_class_key request_key;	  \
653 		devm_gpiochip_add_data_with_key(dev, gc, data, &lock_key, \
654 					   &request_key);	  \
655 	})
656 #else
657 #define gpiochip_add_data(gc, data) gpiochip_add_data_with_key(gc, data, NULL, NULL)
658 #define devm_gpiochip_add_data(dev, gc, data) \
659 	devm_gpiochip_add_data_with_key(dev, gc, data, NULL, NULL)
660 #endif /* CONFIG_LOCKDEP */
661 
662 void gpiochip_remove(struct gpio_chip *gc);
663 int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc,
664 				    void *data, struct lock_class_key *lock_key,
665 				    struct lock_class_key *request_key);
666 
667 struct gpio_device *gpio_device_find(const void *data,
668 				int (*match)(struct gpio_chip *gc,
669 					     const void *data));
670 
671 struct gpio_device *gpio_device_get(struct gpio_device *gdev);
672 void gpio_device_put(struct gpio_device *gdev);
673 
674 DEFINE_FREE(gpio_device_put, struct gpio_device *,
675 	    if (!IS_ERR_OR_NULL(_T)) gpio_device_put(_T))
676 
677 struct device *gpio_device_to_device(struct gpio_device *gdev);
678 
679 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset);
680 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset);
681 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset);
682 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset);
683 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset);
684 
685 /* irq_data versions of the above */
686 int gpiochip_irq_reqres(struct irq_data *data);
687 void gpiochip_irq_relres(struct irq_data *data);
688 
689 /* Paste this in your irq_chip structure  */
690 #define	GPIOCHIP_IRQ_RESOURCE_HELPERS					\
691 		.irq_request_resources  = gpiochip_irq_reqres,		\
692 		.irq_release_resources  = gpiochip_irq_relres
693 
gpio_irq_chip_set_chip(struct gpio_irq_chip * girq,const struct irq_chip * chip)694 static inline void gpio_irq_chip_set_chip(struct gpio_irq_chip *girq,
695 					  const struct irq_chip *chip)
696 {
697 	/* Yes, dropping const is ugly, but it isn't like we have a choice */
698 	girq->chip = (struct irq_chip *)chip;
699 }
700 
701 /* Line status inquiry for drivers */
702 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset);
703 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset);
704 
705 /* Sleep persistence inquiry for drivers */
706 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset);
707 bool gpiochip_line_is_valid(const struct gpio_chip *gc, unsigned int offset);
708 const unsigned long *gpiochip_query_valid_mask(const struct gpio_chip *gc);
709 
710 /* get driver data */
711 void *gpiochip_get_data(struct gpio_chip *gc);
712 
713 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
714 
715 int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
716 					    union gpio_irq_fwspec *gfwspec,
717 					    unsigned int parent_hwirq,
718 					    unsigned int parent_type);
719 int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
720 					     union gpio_irq_fwspec *gfwspec,
721 					     unsigned int parent_hwirq,
722 					     unsigned int parent_type);
723 
724 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
725 
726 int bgpio_init(struct gpio_chip *gc, struct device *dev,
727 	       unsigned long sz, void __iomem *dat, void __iomem *set,
728 	       void __iomem *clr, void __iomem *dirout, void __iomem *dirin,
729 	       unsigned long flags);
730 
731 #define BGPIOF_BIG_ENDIAN		BIT(0)
732 #define BGPIOF_UNREADABLE_REG_SET	BIT(1) /* reg_set is unreadable */
733 #define BGPIOF_UNREADABLE_REG_DIR	BIT(2) /* reg_dir is unreadable */
734 #define BGPIOF_BIG_ENDIAN_BYTE_ORDER	BIT(3)
735 #define BGPIOF_READ_OUTPUT_REG_SET	BIT(4) /* reg_set stores output value */
736 #define BGPIOF_NO_OUTPUT		BIT(5) /* only input */
737 #define BGPIOF_NO_SET_ON_INPUT		BIT(6)
738 #define BGPIOF_PINCTRL_BACKEND		BIT(7) /* Call pinctrl direction setters */
739 #define BGPIOF_NO_INPUT			BIT(8) /* only output */
740 
741 #ifdef CONFIG_GPIOLIB_IRQCHIP
742 int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
743 				struct irq_domain *domain);
744 #else
745 
746 #include <asm/bug.h>
747 
gpiochip_irqchip_add_domain(struct gpio_chip * gc,struct irq_domain * domain)748 static inline int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
749 					      struct irq_domain *domain)
750 {
751 	WARN_ON(1);
752 	return -EINVAL;
753 }
754 #endif
755 
756 int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset);
757 void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset);
758 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
759 			    unsigned long config);
760 
761 /**
762  * struct gpio_pin_range - pin range controlled by a gpio chip
763  * @node: list for maintaining set of pin ranges, used internally
764  * @pctldev: pinctrl device which handles corresponding pins
765  * @range: actual range of pins controlled by a gpio controller
766  */
767 struct gpio_pin_range {
768 	struct list_head node;
769 	struct pinctrl_dev *pctldev;
770 	struct pinctrl_gpio_range range;
771 };
772 
773 #ifdef CONFIG_PINCTRL
774 
775 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
776 			   unsigned int gpio_offset, unsigned int pin_offset,
777 			   unsigned int npins);
778 int gpiochip_add_pingroup_range(struct gpio_chip *gc,
779 			struct pinctrl_dev *pctldev,
780 			unsigned int gpio_offset, const char *pin_group);
781 void gpiochip_remove_pin_ranges(struct gpio_chip *gc);
782 
783 #else /* ! CONFIG_PINCTRL */
784 
785 static inline int
gpiochip_add_pin_range(struct gpio_chip * gc,const char * pinctl_name,unsigned int gpio_offset,unsigned int pin_offset,unsigned int npins)786 gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
787 		       unsigned int gpio_offset, unsigned int pin_offset,
788 		       unsigned int npins)
789 {
790 	return 0;
791 }
792 static inline int
gpiochip_add_pingroup_range(struct gpio_chip * gc,struct pinctrl_dev * pctldev,unsigned int gpio_offset,const char * pin_group)793 gpiochip_add_pingroup_range(struct gpio_chip *gc,
794 			struct pinctrl_dev *pctldev,
795 			unsigned int gpio_offset, const char *pin_group)
796 {
797 	return 0;
798 }
799 
800 static inline void
gpiochip_remove_pin_ranges(struct gpio_chip * gc)801 gpiochip_remove_pin_ranges(struct gpio_chip *gc)
802 {
803 }
804 
805 #endif /* CONFIG_PINCTRL */
806 
807 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
808 					    unsigned int hwnum,
809 					    const char *label,
810 					    enum gpio_lookup_flags lflags,
811 					    enum gpiod_flags dflags);
812 void gpiochip_free_own_desc(struct gpio_desc *desc);
813 
814 struct gpio_desc *
815 gpio_device_get_desc(struct gpio_device *gdev, unsigned int hwnum);
816 
817 struct gpio_chip *gpio_device_get_chip(struct gpio_device *gdev);
818 
819 #ifdef CONFIG_GPIOLIB
820 
821 /* lock/unlock as IRQ */
822 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
823 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);
824 
825 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
826 struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc);
827 
828 /* struct gpio_device getters */
829 int gpio_device_get_base(struct gpio_device *gdev);
830 const char *gpio_device_get_label(struct gpio_device *gdev);
831 
832 struct gpio_device *gpio_device_find_by_label(const char *label);
833 struct gpio_device *gpio_device_find_by_fwnode(const struct fwnode_handle *fwnode);
834 
835 #else /* CONFIG_GPIOLIB */
836 
837 #include <asm/bug.h>
838 
gpiod_to_chip(const struct gpio_desc * desc)839 static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
840 {
841 	/* GPIO can never have been requested */
842 	WARN_ON(1);
843 	return ERR_PTR(-ENODEV);
844 }
845 
gpiod_to_gpio_device(struct gpio_desc * desc)846 static inline struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc)
847 {
848 	WARN_ON(1);
849 	return ERR_PTR(-ENODEV);
850 }
851 
gpio_device_get_base(struct gpio_device * gdev)852 static inline int gpio_device_get_base(struct gpio_device *gdev)
853 {
854 	WARN_ON(1);
855 	return -ENODEV;
856 }
857 
gpio_device_get_label(struct gpio_device * gdev)858 static inline const char *gpio_device_get_label(struct gpio_device *gdev)
859 {
860 	WARN_ON(1);
861 	return NULL;
862 }
863 
gpio_device_find_by_label(const char * label)864 static inline struct gpio_device *gpio_device_find_by_label(const char *label)
865 {
866 	WARN_ON(1);
867 	return NULL;
868 }
869 
gpio_device_find_by_fwnode(const struct fwnode_handle * fwnode)870 static inline struct gpio_device *gpio_device_find_by_fwnode(const struct fwnode_handle *fwnode)
871 {
872 	WARN_ON(1);
873 	return NULL;
874 }
875 
gpiochip_lock_as_irq(struct gpio_chip * gc,unsigned int offset)876 static inline int gpiochip_lock_as_irq(struct gpio_chip *gc,
877 				       unsigned int offset)
878 {
879 	WARN_ON(1);
880 	return -EINVAL;
881 }
882 
gpiochip_unlock_as_irq(struct gpio_chip * gc,unsigned int offset)883 static inline void gpiochip_unlock_as_irq(struct gpio_chip *gc,
884 					  unsigned int offset)
885 {
886 	WARN_ON(1);
887 }
888 #endif /* CONFIG_GPIOLIB */
889 
890 #define for_each_gpiochip_node(dev, child)					\
891 	device_for_each_child_node(dev, child)					\
892 		for_each_if(fwnode_property_present(child, "gpio-controller"))
893 
gpiochip_node_count(struct device * dev)894 static inline unsigned int gpiochip_node_count(struct device *dev)
895 {
896 	struct fwnode_handle *child;
897 	unsigned int count = 0;
898 
899 	for_each_gpiochip_node(dev, child)
900 		count++;
901 
902 	return count;
903 }
904 
gpiochip_node_get_first(struct device * dev)905 static inline struct fwnode_handle *gpiochip_node_get_first(struct device *dev)
906 {
907 	struct fwnode_handle *fwnode;
908 
909 	for_each_gpiochip_node(dev, fwnode)
910 		return fwnode;
911 
912 	return NULL;
913 }
914 
915 #endif /* __LINUX_GPIO_DRIVER_H */
916