[PATCH v4 5/5] regulator: qcom: labibb: Add SC interrupt handling
From: Sumit Semwal
Date: Tue Jun 02 2020 - 06:10:13 EST
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