|  | // SPDX-License-Identifier: GPL-2.0-only | 
|  | // Copyright (c) 2020, The Linux Foundation. All rights reserved. | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/of_irq.h> | 
|  | #include <linux/of.h> | 
|  | #include <linux/of_device.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/regmap.h> | 
|  | #include <linux/regulator/driver.h> | 
|  | #include <linux/regulator/of_regulator.h> | 
|  |  | 
|  | #define REG_PERPH_TYPE                  0x04 | 
|  |  | 
|  | #define QCOM_LAB_TYPE			0x24 | 
|  | #define QCOM_IBB_TYPE			0x20 | 
|  |  | 
|  | #define PMI8998_LAB_REG_BASE		0xde00 | 
|  | #define PMI8998_IBB_REG_BASE		0xdc00 | 
|  | #define PMI8998_IBB_LAB_REG_OFFSET	0x200 | 
|  |  | 
|  | #define REG_LABIBB_STATUS1		0x08 | 
|  | #define LABIBB_STATUS1_SC_BIT		BIT(6) | 
|  | #define LABIBB_STATUS1_VREG_OK_BIT	BIT(7) | 
|  |  | 
|  | #define REG_LABIBB_INT_SET_TYPE		0x11 | 
|  | #define REG_LABIBB_INT_POLARITY_HIGH	0x12 | 
|  | #define REG_LABIBB_INT_POLARITY_LOW	0x13 | 
|  | #define REG_LABIBB_INT_LATCHED_CLR	0x14 | 
|  | #define REG_LABIBB_INT_EN_SET		0x15 | 
|  | #define REG_LABIBB_INT_EN_CLR		0x16 | 
|  | #define LABIBB_INT_VREG_OK		BIT(0) | 
|  | #define LABIBB_INT_VREG_TYPE_LEVEL	0 | 
|  |  | 
|  | #define REG_LABIBB_VOLTAGE		0x41 | 
|  | #define LABIBB_VOLTAGE_OVERRIDE_EN	BIT(7) | 
|  | #define LAB_VOLTAGE_SET_MASK		GENMASK(3, 0) | 
|  | #define IBB_VOLTAGE_SET_MASK		GENMASK(5, 0) | 
|  |  | 
|  | #define REG_LABIBB_ENABLE_CTL		0x46 | 
|  | #define LABIBB_CONTROL_ENABLE		BIT(7) | 
|  |  | 
|  | #define REG_LABIBB_PD_CTL		0x47 | 
|  | #define LAB_PD_CTL_MASK		GENMASK(1, 0) | 
|  | #define IBB_PD_CTL_MASK		(BIT(0) | BIT(7)) | 
|  | #define LAB_PD_CTL_STRONG_PULL		BIT(0) | 
|  | #define IBB_PD_CTL_HALF_STRENGTH	BIT(0) | 
|  | #define IBB_PD_CTL_EN			BIT(7) | 
|  |  | 
|  | #define REG_LABIBB_CURRENT_LIMIT	0x4b | 
|  | #define LAB_CURRENT_LIMIT_MASK		GENMASK(2, 0) | 
|  | #define IBB_CURRENT_LIMIT_MASK		GENMASK(4, 0) | 
|  | #define LAB_CURRENT_LIMIT_OVERRIDE_EN	BIT(3) | 
|  | #define LABIBB_CURRENT_LIMIT_EN	BIT(7) | 
|  |  | 
|  | #define REG_IBB_PWRUP_PWRDN_CTL_1	0x58 | 
|  | #define IBB_CTL_1_DISCHARGE_EN		BIT(2) | 
|  |  | 
|  | #define REG_LABIBB_SOFT_START_CTL	0x5f | 
|  | #define REG_LABIBB_SEC_ACCESS		0xd0 | 
|  | #define LABIBB_SEC_UNLOCK_CODE		0xa5 | 
|  |  | 
|  | #define LAB_ENABLE_CTL_MASK		BIT(7) | 
|  | #define IBB_ENABLE_CTL_MASK		(BIT(7) | BIT(6)) | 
|  |  | 
|  | #define LABIBB_OFF_ON_DELAY		1000 | 
|  | #define LAB_ENABLE_TIME			(LABIBB_OFF_ON_DELAY * 2) | 
|  | #define IBB_ENABLE_TIME			(LABIBB_OFF_ON_DELAY * 10) | 
|  | #define LABIBB_POLL_ENABLED_TIME	1000 | 
|  | #define OCP_RECOVERY_INTERVAL_MS	500 | 
|  | #define SC_RECOVERY_INTERVAL_MS		250 | 
|  | #define LABIBB_MAX_OCP_COUNT		4 | 
|  | #define LABIBB_MAX_SC_COUNT		3 | 
|  | #define LABIBB_MAX_FATAL_COUNT		2 | 
|  |  | 
|  | struct labibb_current_limits { | 
|  | u32				uA_min; | 
|  | u32				uA_step; | 
|  | u8				ovr_val; | 
|  | }; | 
|  |  | 
|  | struct labibb_regulator { | 
|  | struct regulator_desc		desc; | 
|  | struct device			*dev; | 
|  | struct regmap			*regmap; | 
|  | struct regulator_dev		*rdev; | 
|  | struct labibb_current_limits	uA_limits; | 
|  | struct delayed_work		ocp_recovery_work; | 
|  | struct delayed_work		sc_recovery_work; | 
|  | u16				base; | 
|  | u8				type; | 
|  | u8				dischg_sel; | 
|  | u8				soft_start_sel; | 
|  | int				sc_irq; | 
|  | int				sc_count; | 
|  | int				ocp_irq; | 
|  | int				ocp_irq_count; | 
|  | int				fatal_count; | 
|  | }; | 
|  |  | 
|  | struct labibb_regulator_data { | 
|  | const char			*name; | 
|  | u8				type; | 
|  | u16				base; | 
|  | const struct regulator_desc	*desc; | 
|  | }; | 
|  |  | 
|  | static int qcom_labibb_ocp_hw_enable(struct regulator_dev *rdev) | 
|  | { | 
|  | struct labibb_regulator *vreg = rdev_get_drvdata(rdev); | 
|  | int ret; | 
|  |  | 
|  | /* Clear irq latch status to avoid spurious event */ | 
|  | ret = regmap_update_bits(rdev->regmap, | 
|  | vreg->base + REG_LABIBB_INT_LATCHED_CLR, | 
|  | LABIBB_INT_VREG_OK, 1); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | /* Enable OCP HW interrupt */ | 
|  | return regmap_update_bits(rdev->regmap, | 
|  | vreg->base + REG_LABIBB_INT_EN_SET, | 
|  | LABIBB_INT_VREG_OK, 1); | 
|  | } | 
|  |  | 
|  | static int qcom_labibb_ocp_hw_disable(struct regulator_dev *rdev) | 
|  | { | 
|  | struct labibb_regulator *vreg = rdev_get_drvdata(rdev); | 
|  |  | 
|  | return regmap_update_bits(rdev->regmap, | 
|  | vreg->base + REG_LABIBB_INT_EN_CLR, | 
|  | LABIBB_INT_VREG_OK, 1); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * qcom_labibb_check_ocp_status - Check the Over-Current Protection status | 
|  | * @vreg: Main driver structure | 
|  | * | 
|  | * This function checks the STATUS1 register for the VREG_OK bit: if it is | 
|  | * set, then there is no Over-Current event. | 
|  | * | 
|  | * Returns: Zero if there is no over-current, 1 if in over-current or | 
|  | *          negative number for error | 
|  | */ | 
|  | static int qcom_labibb_check_ocp_status(struct labibb_regulator *vreg) | 
|  | { | 
|  | u32 cur_status; | 
|  | int ret; | 
|  |  | 
|  | ret = regmap_read(vreg->rdev->regmap, vreg->base + REG_LABIBB_STATUS1, | 
|  | &cur_status); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | return !(cur_status & LABIBB_STATUS1_VREG_OK_BIT); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * qcom_labibb_ocp_recovery_worker - Handle OCP event | 
|  | * @work: OCP work structure | 
|  | * | 
|  | * This is the worker function to handle the Over Current Protection | 
|  | * hardware event; This will check if the hardware is still | 
|  | * signaling an over-current condition and will eventually stop | 
|  | * the regulator if such condition is still signaled after | 
|  | * LABIBB_MAX_OCP_COUNT times. | 
|  | * | 
|  | * If the driver that is consuming the regulator did not take action | 
|  | * for the OCP condition, or the hardware did not stabilize, a cut | 
|  | * of the LAB and IBB regulators will be forced (regulators will be | 
|  | * disabled). | 
|  | * | 
|  | * As last, if the writes to shut down the LAB/IBB regulators fail | 
|  | * for more than LABIBB_MAX_FATAL_COUNT, then a kernel panic will be | 
|  | * triggered, as a last resort to protect the hardware from burning; | 
|  | * this, however, is expected to never happen, but this is kept to | 
|  | * try to further ensure that we protect the hardware at all costs. | 
|  | */ | 
|  | static void qcom_labibb_ocp_recovery_worker(struct work_struct *work) | 
|  | { | 
|  | struct labibb_regulator *vreg; | 
|  | const struct regulator_ops *ops; | 
|  | int ret; | 
|  |  | 
|  | vreg = container_of(work, struct labibb_regulator, | 
|  | ocp_recovery_work.work); | 
|  | ops = vreg->rdev->desc->ops; | 
|  |  | 
|  | if (vreg->ocp_irq_count >= LABIBB_MAX_OCP_COUNT) { | 
|  | /* | 
|  | * If we tried to disable the regulator multiple times but | 
|  | * we kept failing, there's only one last hope to save our | 
|  | * hardware from the death: raise a kernel bug, reboot and | 
|  | * hope that the bootloader kindly saves us. This, though | 
|  | * is done only as paranoid checking, because failing the | 
|  | * regmap write to disable the vreg is almost impossible, | 
|  | * since we got here after multiple regmap R/W. | 
|  | */ | 
|  | BUG_ON(vreg->fatal_count > LABIBB_MAX_FATAL_COUNT); | 
|  | dev_err(&vreg->rdev->dev, "LABIBB: CRITICAL: Disabling regulator\n"); | 
|  |  | 
|  | /* Disable the regulator immediately to avoid damage */ | 
|  | ret = ops->disable(vreg->rdev); | 
|  | if (ret) { | 
|  | vreg->fatal_count++; | 
|  | goto reschedule; | 
|  | } | 
|  | enable_irq(vreg->ocp_irq); | 
|  | vreg->fatal_count = 0; | 
|  | return; | 
|  | } | 
|  |  | 
|  | ret = qcom_labibb_check_ocp_status(vreg); | 
|  | if (ret != 0) { | 
|  | vreg->ocp_irq_count++; | 
|  | goto reschedule; | 
|  | } | 
|  |  | 
|  | ret = qcom_labibb_ocp_hw_enable(vreg->rdev); | 
|  | if (ret) { | 
|  | /* We cannot trust it without OCP enabled. */ | 
|  | dev_err(vreg->dev, "Cannot enable OCP IRQ\n"); | 
|  | vreg->ocp_irq_count++; | 
|  | goto reschedule; | 
|  | } | 
|  |  | 
|  | enable_irq(vreg->ocp_irq); | 
|  | /* Everything went fine: reset the OCP count! */ | 
|  | vreg->ocp_irq_count = 0; | 
|  | return; | 
|  |  | 
|  | reschedule: | 
|  | mod_delayed_work(system_wq, &vreg->ocp_recovery_work, | 
|  | msecs_to_jiffies(OCP_RECOVERY_INTERVAL_MS)); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * qcom_labibb_ocp_isr - Interrupt routine for OverCurrent Protection | 
|  | * @irq:  Interrupt number | 
|  | * @chip: Main driver structure | 
|  | * | 
|  | * Over Current Protection (OCP) will signal to the client driver | 
|  | * that an over-current event has happened and then will schedule | 
|  | * a recovery worker. | 
|  | * | 
|  | * Disabling and eventually re-enabling the regulator is expected | 
|  | * to be done by the driver, as some hardware may be triggering an | 
|  | * over-current condition only at first initialization or it may | 
|  | * be expected only for a very brief amount of time, after which | 
|  | * the attached hardware may be expected to stabilize its current | 
|  | * draw. | 
|  | * | 
|  | * Returns: IRQ_HANDLED for success or IRQ_NONE for failure. | 
|  | */ | 
|  | static irqreturn_t qcom_labibb_ocp_isr(int irq, void *chip) | 
|  | { | 
|  | struct labibb_regulator *vreg = chip; | 
|  | const struct regulator_ops *ops = vreg->rdev->desc->ops; | 
|  | int ret; | 
|  |  | 
|  | /* If the regulator is not enabled, this is a fake event */ | 
|  | if (!ops->is_enabled(vreg->rdev)) | 
|  | return IRQ_HANDLED; | 
|  |  | 
|  | /* If we tried to recover for too many times it's not getting better */ | 
|  | if (vreg->ocp_irq_count > LABIBB_MAX_OCP_COUNT) | 
|  | return IRQ_NONE; | 
|  |  | 
|  | /* | 
|  | * If we (unlikely) can't read this register, to prevent hardware | 
|  | * damage at all costs, we assume that the overcurrent event was | 
|  | * real; Moreover, if the status register is not signaling OCP, | 
|  | * it was a spurious event, so it's all ok. | 
|  | */ | 
|  | ret = qcom_labibb_check_ocp_status(vreg); | 
|  | if (ret == 0) { | 
|  | vreg->ocp_irq_count = 0; | 
|  | goto end; | 
|  | } | 
|  | vreg->ocp_irq_count++; | 
|  |  | 
|  | /* | 
|  | * Disable the interrupt temporarily, or it will fire continuously; | 
|  | * we will re-enable it in the recovery worker function. | 
|  | */ | 
|  | disable_irq_nosync(irq); | 
|  |  | 
|  | /* Warn the user for overcurrent */ | 
|  | dev_warn(vreg->dev, "Over-Current interrupt fired!\n"); | 
|  |  | 
|  | /* Disable the interrupt to avoid hogging */ | 
|  | ret = qcom_labibb_ocp_hw_disable(vreg->rdev); | 
|  | if (ret) | 
|  | goto end; | 
|  |  | 
|  | /* Signal overcurrent event to drivers */ | 
|  | regulator_notifier_call_chain(vreg->rdev, | 
|  | REGULATOR_EVENT_OVER_CURRENT, NULL); | 
|  |  | 
|  | end: | 
|  | /* Schedule the recovery work */ | 
|  | schedule_delayed_work(&vreg->ocp_recovery_work, | 
|  | msecs_to_jiffies(OCP_RECOVERY_INTERVAL_MS)); | 
|  | if (ret) | 
|  | return IRQ_NONE; | 
|  |  | 
|  | return IRQ_HANDLED; | 
|  | } | 
|  |  | 
|  | static int qcom_labibb_set_ocp(struct regulator_dev *rdev, int lim, | 
|  | int severity, bool enable) | 
|  | { | 
|  | struct labibb_regulator *vreg = rdev_get_drvdata(rdev); | 
|  | char *ocp_irq_name; | 
|  | u32 irq_flags = IRQF_ONESHOT; | 
|  | int irq_trig_low, ret; | 
|  |  | 
|  | /* | 
|  | * labibb supports only protection - and does not support setting | 
|  | * limit. Furthermore, we don't support disabling protection. | 
|  | */ | 
|  | if (lim || severity != REGULATOR_SEVERITY_PROT || !enable) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* If there is no OCP interrupt, there's nothing to set */ | 
|  | if (vreg->ocp_irq <= 0) | 
|  | return -EINVAL; | 
|  |  | 
|  | ocp_irq_name = devm_kasprintf(vreg->dev, GFP_KERNEL, "%s-over-current", | 
|  | vreg->desc.name); | 
|  | if (!ocp_irq_name) | 
|  | return -ENOMEM; | 
|  |  | 
|  | /* IRQ polarities - LAB: trigger-low, IBB: trigger-high */ | 
|  | switch (vreg->type) { | 
|  | case QCOM_LAB_TYPE: | 
|  | irq_flags |= IRQF_TRIGGER_LOW; | 
|  | irq_trig_low = 1; | 
|  | break; | 
|  | case QCOM_IBB_TYPE: | 
|  | irq_flags |= IRQF_TRIGGER_HIGH; | 
|  | irq_trig_low = 0; | 
|  | break; | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | /* Activate OCP HW level interrupt */ | 
|  | ret = regmap_update_bits(rdev->regmap, | 
|  | vreg->base + REG_LABIBB_INT_SET_TYPE, | 
|  | LABIBB_INT_VREG_OK, | 
|  | LABIBB_INT_VREG_TYPE_LEVEL); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | /* Set OCP interrupt polarity */ | 
|  | ret = regmap_update_bits(rdev->regmap, | 
|  | vreg->base + REG_LABIBB_INT_POLARITY_HIGH, | 
|  | LABIBB_INT_VREG_OK, !irq_trig_low); | 
|  | if (ret) | 
|  | return ret; | 
|  | ret = regmap_update_bits(rdev->regmap, | 
|  | vreg->base + REG_LABIBB_INT_POLARITY_LOW, | 
|  | LABIBB_INT_VREG_OK, irq_trig_low); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = qcom_labibb_ocp_hw_enable(rdev); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | return devm_request_threaded_irq(vreg->dev, vreg->ocp_irq, NULL, | 
|  | qcom_labibb_ocp_isr, irq_flags, | 
|  | ocp_irq_name, vreg); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * qcom_labibb_check_sc_status - Check the Short Circuit Protection status | 
|  | * @vreg: Main driver structure | 
|  | * | 
|  | * This function checks the STATUS1 register on both LAB and IBB regulators | 
|  | * for the ShortCircuit bit: if it is set on *any* of them, then we have | 
|  | * experienced a short-circuit event. | 
|  | * | 
|  | * Returns: Zero if there is no short-circuit, 1 if in short-circuit or | 
|  | *          negative number for error | 
|  | */ | 
|  | static int qcom_labibb_check_sc_status(struct labibb_regulator *vreg) | 
|  | { | 
|  | u32 ibb_status, ibb_reg, lab_status, lab_reg; | 
|  | int ret; | 
|  |  | 
|  | /* We have to work on both regulators due to PBS... */ | 
|  | lab_reg = ibb_reg = vreg->base + REG_LABIBB_STATUS1; | 
|  | if (vreg->type == QCOM_LAB_TYPE) | 
|  | ibb_reg -= PMI8998_IBB_LAB_REG_OFFSET; | 
|  | else | 
|  | lab_reg += PMI8998_IBB_LAB_REG_OFFSET; | 
|  |  | 
|  | ret = regmap_read(vreg->rdev->regmap, lab_reg, &lab_status); | 
|  | if (ret) | 
|  | return ret; | 
|  | ret = regmap_read(vreg->rdev->regmap, ibb_reg, &ibb_status); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | return !!(lab_status & LABIBB_STATUS1_SC_BIT) || | 
|  | !!(ibb_status & LABIBB_STATUS1_SC_BIT); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * qcom_labibb_sc_recovery_worker - Handle Short Circuit event | 
|  | * @work: SC work structure | 
|  | * | 
|  | * This is the worker function to handle the Short Circuit Protection | 
|  | * hardware event; This will check if the hardware is still | 
|  | * signaling a short-circuit condition and will eventually never | 
|  | * re-enable the regulator if such condition is still signaled after | 
|  | * LABIBB_MAX_SC_COUNT times. | 
|  | * | 
|  | * If the driver that is consuming the regulator did not take action | 
|  | * for the SC condition, or the hardware did not stabilize, this | 
|  | * worker will stop rescheduling, leaving the regulators disabled | 
|  | * as already done by the Portable Batch System (PBS). | 
|  | * | 
|  | * Returns: IRQ_HANDLED for success or IRQ_NONE for failure. | 
|  | */ | 
|  | static void qcom_labibb_sc_recovery_worker(struct work_struct *work) | 
|  | { | 
|  | struct labibb_regulator *vreg; | 
|  | const struct regulator_ops *ops; | 
|  | u32 lab_reg, ibb_reg, lab_val, ibb_val, val; | 
|  | bool pbs_cut = false; | 
|  | int i, sc, ret; | 
|  |  | 
|  | vreg = container_of(work, struct labibb_regulator, | 
|  | sc_recovery_work.work); | 
|  | ops = vreg->rdev->desc->ops; | 
|  |  | 
|  | /* | 
|  | * If we tried to check the regulator status multiple times but we | 
|  | * kept failing, then just bail out, as the Portable Batch System | 
|  | * (PBS) will disable the vregs for us, preventing hardware damage. | 
|  | */ | 
|  | if (vreg->fatal_count > LABIBB_MAX_FATAL_COUNT) | 
|  | return; | 
|  |  | 
|  | /* Too many short-circuit events. Throw in the towel. */ | 
|  | if (vreg->sc_count > LABIBB_MAX_SC_COUNT) | 
|  | return; | 
|  |  | 
|  | /* | 
|  | * The Portable Batch System (PBS) automatically disables LAB | 
|  | * and IBB when a short-circuit event is detected, so we have to | 
|  | * check and work on both of them at the same time. | 
|  | */ | 
|  | lab_reg = ibb_reg = vreg->base + REG_LABIBB_ENABLE_CTL; | 
|  | if (vreg->type == QCOM_LAB_TYPE) | 
|  | ibb_reg -= PMI8998_IBB_LAB_REG_OFFSET; | 
|  | else | 
|  | lab_reg += PMI8998_IBB_LAB_REG_OFFSET; | 
|  |  | 
|  | sc = qcom_labibb_check_sc_status(vreg); | 
|  | if (sc) | 
|  | goto reschedule; | 
|  |  | 
|  | for (i = 0; i < LABIBB_MAX_SC_COUNT; i++) { | 
|  | ret = regmap_read(vreg->regmap, lab_reg, &lab_val); | 
|  | if (ret) { | 
|  | vreg->fatal_count++; | 
|  | goto reschedule; | 
|  | } | 
|  |  | 
|  | ret = regmap_read(vreg->regmap, ibb_reg, &ibb_val); | 
|  | if (ret) { | 
|  | vreg->fatal_count++; | 
|  | goto reschedule; | 
|  | } | 
|  | val = lab_val & ibb_val; | 
|  |  | 
|  | if (!(val & LABIBB_CONTROL_ENABLE)) { | 
|  | pbs_cut = true; | 
|  | break; | 
|  | } | 
|  | usleep_range(5000, 6000); | 
|  | } | 
|  | if (pbs_cut) | 
|  | goto reschedule; | 
|  |  | 
|  |  | 
|  | /* | 
|  | * If we have reached this point, we either have successfully | 
|  | * recovered from the SC condition or we had a spurious SC IRQ, | 
|  | * which means that we can re-enable the regulators, if they | 
|  | * have ever been disabled by the PBS. | 
|  | */ | 
|  | ret = ops->enable(vreg->rdev); | 
|  | if (ret) | 
|  | goto reschedule; | 
|  |  | 
|  | /* Everything went fine: reset the OCP count! */ | 
|  | vreg->sc_count = 0; | 
|  | enable_irq(vreg->sc_irq); | 
|  | return; | 
|  |  | 
|  | reschedule: | 
|  | /* | 
|  | * Now that we have done basic handling of the short-circuit, | 
|  | * reschedule this worker in the regular system workqueue, as | 
|  | * taking action is not truly urgent anymore. | 
|  | */ | 
|  | vreg->sc_count++; | 
|  | mod_delayed_work(system_wq, &vreg->sc_recovery_work, | 
|  | msecs_to_jiffies(SC_RECOVERY_INTERVAL_MS)); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * qcom_labibb_sc_isr - Interrupt routine for Short Circuit Protection | 
|  | * @irq:  Interrupt number | 
|  | * @chip: Main driver structure | 
|  | * | 
|  | * Short Circuit Protection (SCP) will signal to the client driver | 
|  | * that a regulation-out event has happened and then will schedule | 
|  | * a recovery worker. | 
|  | * | 
|  | * The LAB and IBB regulators will be automatically disabled by the | 
|  | * Portable Batch System (PBS) and they will be enabled again by | 
|  | * the worker function if the hardware stops signaling the short | 
|  | * circuit event. | 
|  | * | 
|  | * Returns: IRQ_HANDLED for success or IRQ_NONE for failure. | 
|  | */ | 
|  | static irqreturn_t qcom_labibb_sc_isr(int irq, void *chip) | 
|  | { | 
|  | struct labibb_regulator *vreg = chip; | 
|  |  | 
|  | if (vreg->sc_count > LABIBB_MAX_SC_COUNT) | 
|  | return IRQ_NONE; | 
|  |  | 
|  | /* Warn the user for short circuit */ | 
|  | dev_warn(vreg->dev, "Short-Circuit interrupt fired!\n"); | 
|  |  | 
|  | /* | 
|  | * Disable the interrupt temporarily, or it will fire continuously; | 
|  | * we will re-enable it in the recovery worker function. | 
|  | */ | 
|  | disable_irq_nosync(irq); | 
|  |  | 
|  | /* Signal out of regulation event to drivers */ | 
|  | regulator_notifier_call_chain(vreg->rdev, | 
|  | REGULATOR_EVENT_REGULATION_OUT, NULL); | 
|  |  | 
|  | /* Schedule the short-circuit handling as high-priority work */ | 
|  | mod_delayed_work(system_highpri_wq, &vreg->sc_recovery_work, | 
|  | msecs_to_jiffies(SC_RECOVERY_INTERVAL_MS)); | 
|  | return IRQ_HANDLED; | 
|  | } | 
|  |  | 
|  |  | 
|  | static int qcom_labibb_set_current_limit(struct regulator_dev *rdev, | 
|  | int min_uA, int max_uA) | 
|  | { | 
|  | struct labibb_regulator *vreg = rdev_get_drvdata(rdev); | 
|  | struct regulator_desc *desc = &vreg->desc; | 
|  | struct labibb_current_limits *lim = &vreg->uA_limits; | 
|  | u32 mask, val; | 
|  | int i, ret, sel = -1; | 
|  |  | 
|  | if (min_uA < lim->uA_min || max_uA < lim->uA_min) | 
|  | return -EINVAL; | 
|  |  | 
|  | for (i = 0; i < desc->n_current_limits; i++) { | 
|  | int uA_limit = (lim->uA_step * i) + lim->uA_min; | 
|  |  | 
|  | if (max_uA >= uA_limit && min_uA <= uA_limit) | 
|  | sel = i; | 
|  | } | 
|  | if (sel < 0) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* Current limit setting needs secure access */ | 
|  | ret = regmap_write(vreg->regmap, vreg->base + REG_LABIBB_SEC_ACCESS, | 
|  | LABIBB_SEC_UNLOCK_CODE); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | mask = desc->csel_mask | lim->ovr_val; | 
|  | mask |= LABIBB_CURRENT_LIMIT_EN; | 
|  | val = (u32)sel | lim->ovr_val; | 
|  | val |= LABIBB_CURRENT_LIMIT_EN; | 
|  |  | 
|  | return regmap_update_bits(vreg->regmap, desc->csel_reg, mask, val); | 
|  | } | 
|  |  | 
|  | static int qcom_labibb_get_current_limit(struct regulator_dev *rdev) | 
|  | { | 
|  | struct labibb_regulator *vreg = rdev_get_drvdata(rdev); | 
|  | struct regulator_desc *desc = &vreg->desc; | 
|  | struct labibb_current_limits *lim = &vreg->uA_limits; | 
|  | unsigned int cur_step; | 
|  | int ret; | 
|  |  | 
|  | ret = regmap_read(vreg->regmap, desc->csel_reg, &cur_step); | 
|  | if (ret) | 
|  | return ret; | 
|  | cur_step &= desc->csel_mask; | 
|  |  | 
|  | return (cur_step * lim->uA_step) + lim->uA_min; | 
|  | } | 
|  |  | 
|  | static int qcom_labibb_set_soft_start(struct regulator_dev *rdev) | 
|  | { | 
|  | struct labibb_regulator *vreg = rdev_get_drvdata(rdev); | 
|  | u32 val = 0; | 
|  |  | 
|  | if (vreg->type == QCOM_IBB_TYPE) | 
|  | val = vreg->dischg_sel; | 
|  | else | 
|  | val = vreg->soft_start_sel; | 
|  |  | 
|  | return regmap_write(rdev->regmap, rdev->desc->soft_start_reg, val); | 
|  | } | 
|  |  | 
|  | static int qcom_labibb_get_table_sel(const int *table, int sz, u32 value) | 
|  | { | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < sz; i++) | 
|  | if (table[i] == value) | 
|  | return i; | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | /* IBB discharge resistor values in KOhms */ | 
|  | static const int dischg_resistor_values[] = { 300, 64, 32, 16 }; | 
|  |  | 
|  | /* Soft start time in microseconds */ | 
|  | static const int soft_start_values[] = { 200, 400, 600, 800 }; | 
|  |  | 
|  | static int qcom_labibb_of_parse_cb(struct device_node *np, | 
|  | const struct regulator_desc *desc, | 
|  | struct regulator_config *config) | 
|  | { | 
|  | struct labibb_regulator *vreg = config->driver_data; | 
|  | u32 dischg_kohms, soft_start_time; | 
|  | int ret; | 
|  |  | 
|  | ret = of_property_read_u32(np, "qcom,discharge-resistor-kohms", | 
|  | &dischg_kohms); | 
|  | if (ret) | 
|  | dischg_kohms = 300; | 
|  |  | 
|  | ret = qcom_labibb_get_table_sel(dischg_resistor_values, | 
|  | ARRAY_SIZE(dischg_resistor_values), | 
|  | dischg_kohms); | 
|  | if (ret < 0) | 
|  | return ret; | 
|  | vreg->dischg_sel = (u8)ret; | 
|  |  | 
|  | ret = of_property_read_u32(np, "qcom,soft-start-us", | 
|  | &soft_start_time); | 
|  | if (ret) | 
|  | soft_start_time = 200; | 
|  |  | 
|  | ret = qcom_labibb_get_table_sel(soft_start_values, | 
|  | ARRAY_SIZE(soft_start_values), | 
|  | soft_start_time); | 
|  | if (ret < 0) | 
|  | return ret; | 
|  | vreg->soft_start_sel = (u8)ret; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct regulator_ops qcom_labibb_ops = { | 
|  | .enable			= regulator_enable_regmap, | 
|  | .disable		= regulator_disable_regmap, | 
|  | .is_enabled		= regulator_is_enabled_regmap, | 
|  | .set_voltage_sel	= regulator_set_voltage_sel_regmap, | 
|  | .get_voltage_sel	= regulator_get_voltage_sel_regmap, | 
|  | .list_voltage		= regulator_list_voltage_linear, | 
|  | .map_voltage		= regulator_map_voltage_linear, | 
|  | .set_active_discharge	= regulator_set_active_discharge_regmap, | 
|  | .set_pull_down		= regulator_set_pull_down_regmap, | 
|  | .set_current_limit	= qcom_labibb_set_current_limit, | 
|  | .get_current_limit	= qcom_labibb_get_current_limit, | 
|  | .set_soft_start		= qcom_labibb_set_soft_start, | 
|  | .set_over_current_protection = qcom_labibb_set_ocp, | 
|  | }; | 
|  |  | 
|  | static const struct regulator_desc pmi8998_lab_desc = { | 
|  | .enable_mask		= LAB_ENABLE_CTL_MASK, | 
|  | .enable_reg		= (PMI8998_LAB_REG_BASE + REG_LABIBB_ENABLE_CTL), | 
|  | .enable_val		= LABIBB_CONTROL_ENABLE, | 
|  | .enable_time		= LAB_ENABLE_TIME, | 
|  | .poll_enabled_time	= LABIBB_POLL_ENABLED_TIME, | 
|  | .soft_start_reg		= (PMI8998_LAB_REG_BASE + REG_LABIBB_SOFT_START_CTL), | 
|  | .pull_down_reg		= (PMI8998_LAB_REG_BASE + REG_LABIBB_PD_CTL), | 
|  | .pull_down_mask		= LAB_PD_CTL_MASK, | 
|  | .pull_down_val_on	= LAB_PD_CTL_STRONG_PULL, | 
|  | .vsel_reg		= (PMI8998_LAB_REG_BASE + REG_LABIBB_VOLTAGE), | 
|  | .vsel_mask		= LAB_VOLTAGE_SET_MASK, | 
|  | .apply_reg		= (PMI8998_LAB_REG_BASE + REG_LABIBB_VOLTAGE), | 
|  | .apply_bit		= LABIBB_VOLTAGE_OVERRIDE_EN, | 
|  | .csel_reg		= (PMI8998_LAB_REG_BASE + REG_LABIBB_CURRENT_LIMIT), | 
|  | .csel_mask		= LAB_CURRENT_LIMIT_MASK, | 
|  | .n_current_limits	= 8, | 
|  | .off_on_delay		= LABIBB_OFF_ON_DELAY, | 
|  | .owner			= THIS_MODULE, | 
|  | .type			= REGULATOR_VOLTAGE, | 
|  | .min_uV			= 4600000, | 
|  | .uV_step		= 100000, | 
|  | .n_voltages		= 16, | 
|  | .ops			= &qcom_labibb_ops, | 
|  | .of_parse_cb		= qcom_labibb_of_parse_cb, | 
|  | }; | 
|  |  | 
|  | static const struct regulator_desc pmi8998_ibb_desc = { | 
|  | .enable_mask		= IBB_ENABLE_CTL_MASK, | 
|  | .enable_reg		= (PMI8998_IBB_REG_BASE + REG_LABIBB_ENABLE_CTL), | 
|  | .enable_val		= LABIBB_CONTROL_ENABLE, | 
|  | .enable_time		= IBB_ENABLE_TIME, | 
|  | .poll_enabled_time	= LABIBB_POLL_ENABLED_TIME, | 
|  | .soft_start_reg		= (PMI8998_IBB_REG_BASE + REG_LABIBB_SOFT_START_CTL), | 
|  | .active_discharge_off	= 0, | 
|  | .active_discharge_on	= IBB_CTL_1_DISCHARGE_EN, | 
|  | .active_discharge_mask	= IBB_CTL_1_DISCHARGE_EN, | 
|  | .active_discharge_reg	= (PMI8998_IBB_REG_BASE + REG_IBB_PWRUP_PWRDN_CTL_1), | 
|  | .pull_down_reg		= (PMI8998_IBB_REG_BASE + REG_LABIBB_PD_CTL), | 
|  | .pull_down_mask		= IBB_PD_CTL_MASK, | 
|  | .pull_down_val_on	= IBB_PD_CTL_HALF_STRENGTH | IBB_PD_CTL_EN, | 
|  | .vsel_reg		= (PMI8998_IBB_REG_BASE + REG_LABIBB_VOLTAGE), | 
|  | .vsel_mask		= IBB_VOLTAGE_SET_MASK, | 
|  | .apply_reg		= (PMI8998_IBB_REG_BASE + REG_LABIBB_VOLTAGE), | 
|  | .apply_bit		= LABIBB_VOLTAGE_OVERRIDE_EN, | 
|  | .csel_reg		= (PMI8998_IBB_REG_BASE + REG_LABIBB_CURRENT_LIMIT), | 
|  | .csel_mask		= IBB_CURRENT_LIMIT_MASK, | 
|  | .n_current_limits	= 32, | 
|  | .off_on_delay		= LABIBB_OFF_ON_DELAY, | 
|  | .owner			= THIS_MODULE, | 
|  | .type			= REGULATOR_VOLTAGE, | 
|  | .min_uV			= 1400000, | 
|  | .uV_step		= 100000, | 
|  | .n_voltages		= 64, | 
|  | .ops			= &qcom_labibb_ops, | 
|  | .of_parse_cb		= qcom_labibb_of_parse_cb, | 
|  | }; | 
|  |  | 
|  | static const struct labibb_regulator_data pmi8998_labibb_data[] = { | 
|  | {"lab", QCOM_LAB_TYPE, PMI8998_LAB_REG_BASE, &pmi8998_lab_desc}, | 
|  | {"ibb", QCOM_IBB_TYPE, PMI8998_IBB_REG_BASE, &pmi8998_ibb_desc}, | 
|  | { }, | 
|  | }; | 
|  |  | 
|  | static const struct of_device_id qcom_labibb_match[] = { | 
|  | { .compatible = "qcom,pmi8998-lab-ibb", .data = &pmi8998_labibb_data}, | 
|  | { }, | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(of, qcom_labibb_match); | 
|  |  | 
|  | static int qcom_labibb_regulator_probe(struct platform_device *pdev) | 
|  | { | 
|  | struct labibb_regulator *vreg; | 
|  | struct device *dev = &pdev->dev; | 
|  | struct regulator_config cfg = {}; | 
|  | struct device_node *reg_node; | 
|  | const struct labibb_regulator_data *reg_data; | 
|  | struct regmap *reg_regmap; | 
|  | unsigned int type; | 
|  | int ret; | 
|  |  | 
|  | reg_regmap = dev_get_regmap(pdev->dev.parent, NULL); | 
|  | if (!reg_regmap) { | 
|  | dev_err(&pdev->dev, "Couldn't get parent's regmap\n"); | 
|  | return -ENODEV; | 
|  | } | 
|  |  | 
|  | reg_data = device_get_match_data(&pdev->dev); | 
|  | if (!reg_data) | 
|  | return -ENODEV; | 
|  |  | 
|  | for (; reg_data->name; reg_data++) { | 
|  | char *sc_irq_name; | 
|  | int irq = 0; | 
|  |  | 
|  | /* Validate if the type of regulator is indeed | 
|  | * what's mentioned in DT. | 
|  | */ | 
|  | ret = regmap_read(reg_regmap, reg_data->base + REG_PERPH_TYPE, | 
|  | &type); | 
|  | if (ret < 0) { | 
|  | dev_err(dev, | 
|  | "Peripheral type read failed ret=%d\n", | 
|  | ret); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | if (WARN_ON((type != QCOM_LAB_TYPE) && (type != QCOM_IBB_TYPE)) || | 
|  | WARN_ON(type != reg_data->type)) | 
|  | return -EINVAL; | 
|  |  | 
|  | vreg  = devm_kzalloc(&pdev->dev, sizeof(*vreg), | 
|  | GFP_KERNEL); | 
|  | if (!vreg) | 
|  | return -ENOMEM; | 
|  |  | 
|  | sc_irq_name = devm_kasprintf(dev, GFP_KERNEL, | 
|  | "%s-short-circuit", | 
|  | reg_data->name); | 
|  | if (!sc_irq_name) | 
|  | return -ENOMEM; | 
|  |  | 
|  | reg_node = of_get_child_by_name(pdev->dev.of_node, | 
|  | reg_data->name); | 
|  | if (!reg_node) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* The Short Circuit interrupt is critical */ | 
|  | irq = of_irq_get_byname(reg_node, "sc-err"); | 
|  | if (irq <= 0) { | 
|  | if (irq == 0) | 
|  | irq = -EINVAL; | 
|  |  | 
|  | of_node_put(reg_node); | 
|  | return dev_err_probe(vreg->dev, irq, | 
|  | "Short-circuit irq not found.\n"); | 
|  | } | 
|  | vreg->sc_irq = irq; | 
|  |  | 
|  | /* OverCurrent Protection IRQ is optional */ | 
|  | irq = of_irq_get_byname(reg_node, "ocp"); | 
|  | vreg->ocp_irq = irq; | 
|  | vreg->ocp_irq_count = 0; | 
|  | of_node_put(reg_node); | 
|  |  | 
|  | vreg->regmap = reg_regmap; | 
|  | vreg->dev = dev; | 
|  | vreg->base = reg_data->base; | 
|  | vreg->type = reg_data->type; | 
|  | INIT_DELAYED_WORK(&vreg->sc_recovery_work, | 
|  | qcom_labibb_sc_recovery_worker); | 
|  |  | 
|  | if (vreg->ocp_irq > 0) | 
|  | INIT_DELAYED_WORK(&vreg->ocp_recovery_work, | 
|  | qcom_labibb_ocp_recovery_worker); | 
|  |  | 
|  | switch (vreg->type) { | 
|  | case QCOM_LAB_TYPE: | 
|  | /* LAB Limits: 200-1600mA */ | 
|  | vreg->uA_limits.uA_min  = 200000; | 
|  | vreg->uA_limits.uA_step = 200000; | 
|  | vreg->uA_limits.ovr_val = LAB_CURRENT_LIMIT_OVERRIDE_EN; | 
|  | break; | 
|  | case QCOM_IBB_TYPE: | 
|  | /* IBB Limits: 0-1550mA */ | 
|  | vreg->uA_limits.uA_min  = 0; | 
|  | vreg->uA_limits.uA_step = 50000; | 
|  | vreg->uA_limits.ovr_val = 0; /* No override bit */ | 
|  | break; | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | memcpy(&vreg->desc, reg_data->desc, sizeof(vreg->desc)); | 
|  | vreg->desc.of_match = reg_data->name; | 
|  | vreg->desc.name = reg_data->name; | 
|  |  | 
|  | cfg.dev = vreg->dev; | 
|  | cfg.driver_data = vreg; | 
|  | cfg.regmap = vreg->regmap; | 
|  |  | 
|  | vreg->rdev = devm_regulator_register(vreg->dev, &vreg->desc, | 
|  | &cfg); | 
|  |  | 
|  | if (IS_ERR(vreg->rdev)) { | 
|  | dev_err(dev, "qcom_labibb: error registering %s : %d\n", | 
|  | reg_data->name, ret); | 
|  | return PTR_ERR(vreg->rdev); | 
|  | } | 
|  |  | 
|  | ret = devm_request_threaded_irq(vreg->dev, vreg->sc_irq, NULL, | 
|  | qcom_labibb_sc_isr, | 
|  | IRQF_ONESHOT | | 
|  | IRQF_TRIGGER_RISING, | 
|  | sc_irq_name, vreg); | 
|  | if (ret) | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct platform_driver qcom_labibb_regulator_driver = { | 
|  | .driver	= { | 
|  | .name = "qcom-lab-ibb-regulator", | 
|  | .probe_type = PROBE_PREFER_ASYNCHRONOUS, | 
|  | .of_match_table	= qcom_labibb_match, | 
|  | }, | 
|  | .probe = qcom_labibb_regulator_probe, | 
|  | }; | 
|  | module_platform_driver(qcom_labibb_regulator_driver); | 
|  |  | 
|  | MODULE_DESCRIPTION("Qualcomm labibb driver"); | 
|  | MODULE_AUTHOR("Nisha Kumari <nishakumari@codeaurora.org>"); | 
|  | MODULE_AUTHOR("Sumit Semwal <sumit.semwal@linaro.org>"); | 
|  | MODULE_LICENSE("GPL v2"); |