From: Matti Vaittinen matti.vaittinen@fi.rohmeurope.com
[ Upstream commit fb8fee9efdcf084d9e31ba14cc4734d97e5dd972 ]
Quite a few regulator ICs do support setting ramp-delay by writing a value matching the delay to a ramp-delay register.
Provide a simple helper for table-based delay setting.
Signed-off-by: Matti Vaittinen matti.vaittinen@fi.rohmeurope.com Link: https://lore.kernel.org/r/f101f1db564cf32cb58719c77af0b00d7236bb89.161702071... Signed-off-by: Mark Brown broonie@kernel.org Stable-dep-of: d67dada3e252 ("regulator: pca9450: Fix BUCK2 enable_mask") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/regulator/helpers.c | 65 ++++++++++++++++++++++++++++++++ include/linux/regulator/driver.h | 5 +++ 2 files changed, 70 insertions(+)
diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c index e4bb09bbd3fa6..a356f84b1285b 100644 --- a/drivers/regulator/helpers.c +++ b/drivers/regulator/helpers.c @@ -879,3 +879,68 @@ bool regulator_is_equal(struct regulator *reg1, struct regulator *reg2) return reg1->rdev == reg2->rdev; } EXPORT_SYMBOL_GPL(regulator_is_equal); + +static int find_closest_bigger(unsigned int target, const unsigned int *table, + unsigned int num_sel, unsigned int *sel) +{ + unsigned int s, tmp, max, maxsel = 0; + bool found = false; + + max = table[0]; + + for (s = 0; s < num_sel; s++) { + if (table[s] > max) { + max = table[s]; + maxsel = s; + } + if (table[s] >= target) { + if (!found || table[s] - target < tmp - target) { + tmp = table[s]; + *sel = s; + found = true; + if (tmp == target) + break; + } + } + } + + if (!found) { + *sel = maxsel; + return -EINVAL; + } + + return 0; +} + +/** + * regulator_set_ramp_delay_regmap - set_ramp_delay() helper + * + * @rdev: regulator to operate on + * + * Regulators that use regmap for their register I/O can set the ramp_reg + * and ramp_mask fields in their descriptor and then use this as their + * set_ramp_delay operation, saving some code. + */ +int regulator_set_ramp_delay_regmap(struct regulator_dev *rdev, int ramp_delay) +{ + int ret; + unsigned int sel; + + if (!rdev->desc->n_ramp_values) + return -EINVAL; + + ret = find_closest_bigger(ramp_delay, rdev->desc->ramp_delay_table, + rdev->desc->n_ramp_values, &sel); + + if (ret) { + dev_warn(rdev_get_dev(rdev), + "Can't set ramp-delay %u, setting %u\n", ramp_delay, + rdev->desc->ramp_delay_table[sel]); + } + + sel <<= ffs(rdev->desc->ramp_mask) - 1; + + return regmap_update_bits(rdev->regmap, rdev->desc->ramp_reg, + rdev->desc->ramp_mask, sel); +} +EXPORT_SYMBOL_GPL(regulator_set_ramp_delay_regmap); diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h index 11cade73726ce..633e7a2ab01d0 100644 --- a/include/linux/regulator/driver.h +++ b/include/linux/regulator/driver.h @@ -370,6 +370,10 @@ struct regulator_desc { unsigned int pull_down_reg; unsigned int pull_down_mask; unsigned int pull_down_val_on; + unsigned int ramp_reg; + unsigned int ramp_mask; + const unsigned int *ramp_delay_table; + unsigned int n_ramp_values;
unsigned int enable_time;
@@ -532,6 +536,7 @@ int regulator_set_current_limit_regmap(struct regulator_dev *rdev, int min_uA, int max_uA); int regulator_get_current_limit_regmap(struct regulator_dev *rdev); void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data); +int regulator_set_ramp_delay_regmap(struct regulator_dev *rdev, int ramp_delay);
/* * Helper functions intended to be used by regulator drivers prior registering