1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * coupler.h -- SoC Regulator support, coupler API.
4  *
5  * Regulator Coupler Interface.
6  */
7 
8 #ifndef __LINUX_REGULATOR_COUPLER_H_
9 #define __LINUX_REGULATOR_COUPLER_H_
10 
11 #include <linux/kernel.h>
12 #include <linux/suspend.h>
13 
14 struct regulator_coupler;
15 struct regulator_dev;
16 
17 /**
18  * struct regulator_coupler - customized regulator's coupler
19  *
20  * Regulator's coupler allows to customize coupling algorithm.
21  *
22  * @list: couplers list entry
23  * @attach_regulator: Callback invoked on creation of a coupled regulator,
24  *                    couples are unresolved at this point. The callee should
25  *                    check that it could handle the regulator and return 0 on
26  *                    success, -errno on failure and 1 if given regulator is
27  *                    not suitable for this coupler (case of having multiple
28  *                    regulators in a system). Callback shall be implemented.
29  * @detach_regulator: Callback invoked on destruction of a coupled regulator.
30  *                    This callback is optional and could be NULL.
31  * @balance_voltage: Callback invoked when voltage of a coupled regulator is
32  *                   changing. Called with all of the coupled rdev's being held
33  *                   under "consumer lock". The callee should perform voltage
34  *                   balancing, changing voltage of the coupled regulators as
35  *                   needed. It's up to the coupler to verify the voltage
36  *                   before changing it in hardware, i.e. coupler should
37  *                   check consumer's min/max and etc. This callback is
38  *                   optional and could be NULL, in which case a generic
39  *                   voltage balancer will be used.
40  */
41 struct regulator_coupler {
42 	struct list_head list;
43 
44 	int (*attach_regulator)(struct regulator_coupler *coupler,
45 				struct regulator_dev *rdev);
46 	int (*detach_regulator)(struct regulator_coupler *coupler,
47 				struct regulator_dev *rdev);
48 	int (*balance_voltage)(struct regulator_coupler *coupler,
49 			       struct regulator_dev *rdev,
50 			       suspend_state_t state);
51 };
52 
53 #ifdef CONFIG_REGULATOR
54 int regulator_coupler_register(struct regulator_coupler *coupler);
55 int regulator_check_consumers(struct regulator_dev *rdev,
56 			      int *min_uV, int *max_uV,
57 			      suspend_state_t state);
58 int regulator_check_voltage(struct regulator_dev *rdev,
59 			    int *min_uV, int *max_uV);
60 int regulator_get_voltage_rdev(struct regulator_dev *rdev);
61 int regulator_set_voltage_rdev(struct regulator_dev *rdev,
62 			       int min_uV, int max_uV,
63 			       suspend_state_t state);
64 int regulator_do_balance_voltage(struct regulator_dev *rdev,
65 				 suspend_state_t state, bool skip_coupled);
66 #else
regulator_coupler_register(struct regulator_coupler * coupler)67 static inline int regulator_coupler_register(struct regulator_coupler *coupler)
68 {
69 	return 0;
70 }
regulator_check_consumers(struct regulator_dev * rdev,int * min_uV,int * max_uV,suspend_state_t state)71 static inline int regulator_check_consumers(struct regulator_dev *rdev,
72 					    int *min_uV, int *max_uV,
73 					    suspend_state_t state)
74 {
75 	return -EINVAL;
76 }
regulator_check_voltage(struct regulator_dev * rdev,int * min_uV,int * max_uV)77 static inline int regulator_check_voltage(struct regulator_dev *rdev,
78 					  int *min_uV, int *max_uV)
79 {
80 	return -EINVAL;
81 }
regulator_get_voltage_rdev(struct regulator_dev * rdev)82 static inline int regulator_get_voltage_rdev(struct regulator_dev *rdev)
83 {
84 	return -EINVAL;
85 }
regulator_set_voltage_rdev(struct regulator_dev * rdev,int min_uV,int max_uV,suspend_state_t state)86 static inline int regulator_set_voltage_rdev(struct regulator_dev *rdev,
87 					     int min_uV, int max_uV,
88 					     suspend_state_t state)
89 {
90 	return -EINVAL;
91 }
regulator_do_balance_voltage(struct regulator_dev * rdev,suspend_state_t state,bool skip_coupled)92 static inline int regulator_do_balance_voltage(struct regulator_dev *rdev,
93 					       suspend_state_t state,
94 					       bool skip_coupled)
95 {
96 	return -EINVAL;
97 }
98 #endif
99 
100 #endif
101