From a3d70dacc727ada212aecb8d131a3910622763d6 Mon Sep 17 00:00:00 2001 From: Lucas Stach Date: Tue, 19 Nov 2019 18:00:04 +0100 Subject: [PATCH] power: suppy: ucs1002: disable power when max current is 0 For some devices userspace needs the ability to completely cut the power to the USB devices connected to the charge controller. An easy way to achieve this is by allowing 0 as a valid max current and forcibly disable the output in that case, as well as enable it again if the regulator is in use and a non-0 max current is set. Signed-off-by: Lucas Stach Tested-by: Chris Healy Signed-off-by: Sebastian Reichel --- drivers/power/supply/ucs1002_power.c | 42 +++++++++++++++++++++++++--- 1 file changed, 38 insertions(+), 4 deletions(-) diff --git a/drivers/power/supply/ucs1002_power.c b/drivers/power/supply/ucs1002_power.c index 1b80ae479e7d..0ca80d00b80a 100644 --- a/drivers/power/supply/ucs1002_power.c +++ b/drivers/power/supply/ucs1002_power.c @@ -100,7 +100,9 @@ struct ucs1002_info { struct i2c_client *client; struct regmap *regmap; struct regulator_desc *regulator_descriptor; + struct regulator_dev *rdev; bool present; + bool output_disable; }; static enum power_supply_property ucs1002_props[] = { @@ -233,6 +235,11 @@ static int ucs1002_get_max_current(struct ucs1002_info *info, unsigned int reg; int ret; + if (info->output_disable) { + val->intval = 0; + return 0; + } + ret = regmap_read(info->regmap, UCS1002_REG_ILIMIT, ®); if (ret) return ret; @@ -247,6 +254,12 @@ static int ucs1002_set_max_current(struct ucs1002_info *info, u32 val) unsigned int reg; int ret, idx; + if (val == 0) { + info->output_disable = true; + regulator_disable_regmap(info->rdev); + return 0; + } + for (idx = 0; idx < ARRAY_SIZE(ucs1002_current_limit_uA); idx++) { if (val == ucs1002_current_limit_uA[idx]) break; @@ -270,6 +283,12 @@ static int ucs1002_set_max_current(struct ucs1002_info *info, u32 val) if (reg != idx) return -EINVAL; + info->output_disable = false; + + if (info->rdev && info->rdev->use_count && + !regulator_is_enabled_regmap(info->rdev)) + regulator_enable_regmap(info->rdev); + return 0; } @@ -470,9 +489,24 @@ static irqreturn_t ucs1002_alert_irq(int irq, void *data) return IRQ_HANDLED; } +int ucs1002_regulator_enable(struct regulator_dev *rdev) +{ + struct ucs1002_info *info = rdev_get_drvdata(rdev); + + /* + * If the output is disabled due to 0 maximum current, just pretend the + * enable did work. The regulator will be enabled as soon as we get a + * a non-zero maximum current budget. + */ + if (info->output_disable) + return 0; + + return regulator_enable_regmap(rdev); +} + static const struct regulator_ops ucs1002_regulator_ops = { .is_enabled = regulator_is_enabled_regmap, - .enable = regulator_enable_regmap, + .enable = ucs1002_regulator_enable, .disable = regulator_disable_regmap, }; @@ -499,7 +533,6 @@ static int ucs1002_probe(struct i2c_client *client, }; struct regulator_config regulator_config = {}; int irq_a_det, irq_alert, ret; - struct regulator_dev *rdev; struct ucs1002_info *info; unsigned int regval; @@ -589,10 +622,11 @@ static int ucs1002_probe(struct i2c_client *client, regulator_config.dev = dev; regulator_config.of_node = dev->of_node; regulator_config.regmap = info->regmap; + regulator_config.driver_data = info; - rdev = devm_regulator_register(dev, info->regulator_descriptor, + info->rdev = devm_regulator_register(dev, info->regulator_descriptor, ®ulator_config); - ret = PTR_ERR_OR_ZERO(rdev); + ret = PTR_ERR_OR_ZERO(info->rdev); if (ret) { dev_err(dev, "Failed to register VBUS regulator: %d\n", ret); return ret;