Right now regulator core supports only one type of regulators coupling, the "voltage max-spread" which keeps voltages of coupled regulators in a given range. A more sophisticated coupling may be required in practice, one example is the NVIDIA Tegra SoC's which besides the max-spreading have other restrictions that must be adhered. Introduce API that allow platforms to provide their own custom coupling algorithms.
Signed-off-by: Dmitry Osipenko <[email protected]> --- drivers/regulator/core.c | 18 ++++++++++++++++++ include/linux/regulator/machine.h | 19 +++++++++++++++++++ 2 files changed, 37 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 186a37675b50..a98af47e0feb 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -59,6 +59,8 @@ static bool has_full_constraints; static struct dentry *debugfs_root; +static struct regulators_coupler *machine_regulators_coupler; + /* * struct regulator_map * @@ -3596,6 +3598,12 @@ static int regulator_balance_voltage(struct regulator_dev *rdev, return -EPERM; } + if (n_coupled > 1 && + machine_regulators_coupler && + machine_regulators_coupler->balance_voltage) + return machine_regulators_coupler->balance_voltage( + machine_regulators_coupler, rdev, state); + for (i = 0; i < n_coupled; i++) c_rdev_done[i] = false; @@ -4706,6 +4714,16 @@ static int regulator_register_resolve_supply(struct device *dev, void *data) return 0; } +int regulators_coupler_register(struct regulators_coupler *coupler) +{ + if (WARN_ON(machine_regulators_coupler)) + return -EBUSY; + + machine_regulators_coupler = coupler; + + return 0; +} + static void regulator_resolve_coupling(struct regulator_dev *rdev) { struct coupling_desc *c_desc = &rdev->coupling_desc; diff --git a/include/linux/regulator/machine.h b/include/linux/regulator/machine.h index 1d34a70ffda2..f15c8c5f7f6c 100644 --- a/include/linux/regulator/machine.h +++ b/include/linux/regulator/machine.h @@ -19,6 +19,7 @@ #include <linux/suspend.h> struct regulator; +struct regulator_dev; /* * Regulator operation constraint flags. These flags are used to enable @@ -265,4 +266,22 @@ static inline int regulator_suspend_finish(void) return 0; } +/** + * struct regulators_coupler - machine-specific regulators coupler + * + * A custom regulators coupler allows platform to customize coupling + * algorithm. + * + * @balance_voltage: Callback invoked when voltage of a coupled regulator is + * changing. The callee should perform voltage balancing + * and change voltage of the coupled regulators. + */ +struct regulators_coupler { + int (*balance_voltage)(struct regulators_coupler *coupler, + struct regulator_dev *rdev, + suspend_state_t state); +}; + +int regulators_coupler_register(struct regulators_coupler *coupler); + #endif -- 2.21.0
