diff --git a/drivers/regulator/qcom-labibb-regulator.c b/drivers/regulator/qcom-labibb-regulator.c
index 4d68b69b5a524..dbb4511c3c6d9 100644
--- a/drivers/regulator/qcom-labibb-regulator.c
+++ b/drivers/regulator/qcom-labibb-regulator.c
@@ -17,8 +17,20 @@
#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)
@@ -26,8 +38,7 @@
#define IBB_VOLTAGE_SET_MASK GENMASK(5, 0)
#define REG_LABIBB_ENABLE_CTL 0x46
-#define LABIBB_STATUS1_VREG_OK_BIT BIT(7)
-#define LABIBB_CONTROL_ENABLE BIT(7)
+ #define LABIBB_CONTROL_ENABLE BIT(7)
#define REG_LABIBB_PD_CTL 0x47
#define LAB_PD_CTL_MASK GENMASK(1, 0)
@@ -56,6 +67,11 @@
#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;
@@ -69,10 +85,17 @@ struct labibb_regulator {
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 {
@@ -82,6 +105,450 @@ struct labibb_regulator_data {
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 0;
+
+ /* 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(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)
+{
+ struct labibb_regulator *vreg = rdev_get_drvdata(rdev);
+ char *ocp_irq_name;
+ u32 irq_flags = IRQF_ONESHOT;
+ int irq_trig_low, ret;
+
+ /* 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(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)
{
@@ -210,6 +677,7 @@ static const struct regulator_ops qcom_labibb_ops = {
.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 = {
@@ -287,7 +755,7 @@ 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 of_device_id *match;
const struct labibb_regulator_data *reg_data;
struct regmap *reg_regmap;
@@ -305,6 +773,8 @@ static int qcom_labibb_regulator_probe(struct platform_device *pdev)
return -ENODEV;
for (reg_data = match->data; 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.
@@ -327,10 +797,44 @@ static int qcom_labibb_regulator_probe(struct platform_device *pdev)
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;
+
+ 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:
@@ -365,6 +869,14 @@ static int qcom_labibb_regulator_probe(struct platform_device *pdev)
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;