From: Nisha Kumari <nishakum...@codeaurora.org>
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 <nishakum...@codeaurora.org>
Signed-off-by: Sumit Semwal <sumit.sem...@linaro.org>
--
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.
---
drivers/regulator/qcom-labibb-regulator.c | 92 +++++++++++++++++++++++
1 file changed, 92 insertions(+)
diff --git a/drivers/regulator/qcom-labibb-regulator.c
b/drivers/regulator/qcom-labibb-regulator.c
index 634d08461c6e..695ffac71e81 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 +29,17 @@
#define IBB_POLL_ENABLED_TIME (LABIBB_ENABLE_TIME * 10)
#define LABIBB_OFF_ON_DELAY (8200)
+#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;
+ int sc_irq;
+ int vreg_enabled;
u8 type;
};
@@ -65,6 +72,8 @@ static int qcom_labibb_regulator_enable(struct regulator_dev
*rdev)
if (ret < 0)
dev_err(reg->dev, "Write failed: enable %s regulator\n",
reg->desc.name);
+ else
+ reg->vreg_enabled = 1;
return ret;
}
@@ -78,6 +87,8 @@ static int qcom_labibb_regulator_disable(struct regulator_dev
*rdev)
if (ret < 0)
dev_err(reg->dev, "Disable failed: disable %s\n",
reg->desc.name);
+ else
+ reg->vreg_enabled = 0;
return ret;
}
@@ -88,11 +99,70 @@ 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->vreg_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 int 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;
reg->base = reg_data->base;
reg->type = reg_data->type;
@@ -108,6 +178,28 @@ static int register_labibb_regulator(struct
labibb_regulator *reg,
reg->desc.poll_enabled_time = reg_data->poll_enabled_time;
reg->desc.off_on_delay = LABIBB_OFF_ON_DELAY;
+ reg->sc_irq = -EINVAL;
+ ret = of_irq_get_byname(of_node, "sc-err");
+ if (ret < 0) {
+ dev_err(reg->dev, "Unable to get sc-err, ret = %d\n",
+ ret);
+ return ret;
+ } else
+ reg->sc_irq = ret;
+
+ if (reg->sc_irq > 0) {
+ ret = devm_request_threaded_irq(reg->dev,
+ reg->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 ret;
+ }
+ }
+
cfg.dev = reg->dev;
cfg.driver_data = reg;
cfg.regmap = reg->regmap;
--
2.26.2
