From: Nisha Kumari <nishakumari@xxxxxxxxxxxxxx> Add Short circuit interrupt handling and recovery for the lab and ibb regulators on qcom platforms. The client panel drivers need to register for REGULATOR_EVENT_OVER_CURRENT notification which will be triggered on short circuit. They should try to enable the regulator once, and if it doesn't get enabled, handle shutting down the panel accordingly. Signed-off-by: Nisha Kumari <nishakumari@xxxxxxxxxxxxxx> Signed-off-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx> [sumits: updated to rework to use regmap_read_poll_timeout, handle it per regulator, add REGULATOR_EVENT_OVER_CURRENT handling and notification to clients and other cleanup] -- v2: sumits: reworked handling to user regmap_read_poll_timeout, and handle it per-regulator instead of clearing both lab and ibb errors on either irq triggering. Also added REGULATOR_EVENT_OVER_CURRENT handling and notification to clients. v3: sumits: updated as per review comments of v2: removed spurious check for irq in handler and some unused variables; inlined some of the code, omitted IRQF_TRIGGER_RISING as it's coming from DT. v4: sumits: updated 'int vreg_enabled' to 'boot enabled', made sc_irq a local var and other review comments from v3. --- drivers/regulator/qcom-labibb-regulator.c | 102 +++++++++++++++++++++- 1 file changed, 99 insertions(+), 3 deletions(-) diff --git a/drivers/regulator/qcom-labibb-regulator.c b/drivers/regulator/qcom-labibb-regulator.c index 33b764ac69d1..bca0308b26dd 100644 --- a/drivers/regulator/qcom-labibb-regulator.c +++ b/drivers/regulator/qcom-labibb-regulator.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-only // Copyright (c) 2020, The Linux Foundation. All rights reserved. +#include <linux/interrupt.h> #include <linux/module.h> #include <linux/of_irq.h> #include <linux/of.h> @@ -18,6 +19,7 @@ #define REG_LABIBB_ENABLE_CTL 0x46 #define LABIBB_STATUS1_VREG_OK_BIT BIT(7) #define LABIBB_CONTROL_ENABLE BIT(7) +#define LABIBB_STATUS1_SC_DETECT_BIT BIT(6) #define LAB_ENABLE_CTL_MASK BIT(7) #define IBB_ENABLE_CTL_MASK (BIT(7) | BIT(6)) @@ -27,12 +29,16 @@ #define IBB_ENABLE_TIME (LABIBB_OFF_ON_DELAY * 10) #define LABIBB_POLL_ENABLED_TIME 1000 +#define POLLING_SCP_DONE_INTERVAL_US 5000 +#define POLLING_SCP_TIMEOUT 16000 + struct labibb_regulator { struct regulator_desc desc; struct device *dev; struct regmap *regmap; struct regulator_dev *rdev; u16 base; + bool enabled; u8 type; }; @@ -59,12 +65,26 @@ static int qcom_labibb_regulator_is_enabled(struct regulator_dev *rdev) static int qcom_labibb_regulator_enable(struct regulator_dev *rdev) { - return regulator_enable_regmap(rdev); + int ret; + struct labibb_regulator *reg = rdev_get_drvdata(rdev); + + ret = regulator_enable_regmap(rdev); + if (ret >= 0) + reg->enabled = true; + + return ret; } static int qcom_labibb_regulator_disable(struct regulator_dev *rdev) { - return regulator_disable_regmap(rdev); + int ret = 0; + struct labibb_regulator *reg = rdev_get_drvdata(rdev); + + ret = regulator_disable_regmap(rdev); + if (ret >= 0) + reg->enabled = false; + + return ret; } static struct regulator_ops qcom_labibb_ops = { @@ -73,12 +93,70 @@ static struct regulator_ops qcom_labibb_ops = { .is_enabled = qcom_labibb_regulator_is_enabled, }; +static irqreturn_t labibb_sc_err_handler(int irq, void *_reg) +{ + int ret; + u16 reg; + unsigned int val; + struct labibb_regulator *labibb_reg = _reg; + bool in_sc_err, scp_done = false; + + ret = regmap_read(labibb_reg->regmap, + labibb_reg->base + REG_LABIBB_STATUS1, &val); + if (ret < 0) { + dev_err(labibb_reg->dev, "sc_err_irq: Read failed, ret=%d\n", + ret); + return IRQ_HANDLED; + } + + dev_dbg(labibb_reg->dev, "%s SC error triggered! STATUS1 = %d\n", + labibb_reg->desc.name, val); + + in_sc_err = !!(val & LABIBB_STATUS1_SC_DETECT_BIT); + + /* + * The SC(short circuit) fault would trigger PBS(Portable Batch + * System) to disable regulators for protection. This would + * cause the SC_DETECT status being cleared so that it's not + * able to get the SC fault status. + * Check if the regulator is enabled in the driver but + * disabled in hardware, this means a SC fault had happened + * and SCP handling is completed by PBS. + */ + if (!in_sc_err) { + + reg = labibb_reg->base + REG_LABIBB_ENABLE_CTL; + + ret = regmap_read_poll_timeout(labibb_reg->regmap, + reg, val, + !(val & LABIBB_CONTROL_ENABLE), + POLLING_SCP_DONE_INTERVAL_US, + POLLING_SCP_TIMEOUT); + + if (!ret && labibb_reg->enabled) { + dev_dbg(labibb_reg->dev, + "%s has been disabled by SCP\n", + labibb_reg->desc.name); + scp_done = true; + } + } + + if (in_sc_err || scp_done) { + regulator_lock(labibb_reg->rdev); + regulator_notifier_call_chain(labibb_reg->rdev, + REGULATOR_EVENT_OVER_CURRENT, + NULL); + regulator_unlock(labibb_reg->rdev); + } + return IRQ_HANDLED; +} + static struct regulator_dev *register_labibb_regulator(struct labibb_regulator *reg, const struct labibb_regulator_data *reg_data, struct device_node *of_node) { struct regulator_config cfg = {}; - int ret; + int ret, sc_irq; reg->base = reg_data->base; reg->type = reg_data->type; @@ -95,6 +173,24 @@ static struct regulator_dev *register_labibb_regulator(struct labibb_regulator * reg->desc.poll_enabled_time = LABIBB_POLL_ENABLED_TIME; reg->desc.off_on_delay = LABIBB_OFF_ON_DELAY; + sc_irq = of_irq_get_byname(of_node, "sc-err"); + if (sc_irq < 0) { + dev_err(reg->dev, "Unable to get sc-err, ret = %d\n", + sc_irq); + return ERR_PTR(sc_irq); + } else { + ret = devm_request_threaded_irq(reg->dev, + sc_irq, + NULL, labibb_sc_err_handler, + IRQF_ONESHOT, + "sc-err", reg); + if (ret) { + dev_err(reg->dev, "Failed to register sc-err irq ret=%d\n", + ret); + return ERR_PTR(ret); + } + } + cfg.dev = reg->dev; cfg.driver_data = reg; cfg.regmap = reg->regmap; -- 2.26.2