[PATCH v2 3/3] hwmon: (pmbus/core): Implement irq support

From: Naresh Solanki
Date: Mon Nov 28 2022 - 13:00:48 EST


From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>

Implement PMBUS irq handler to notify regulator events.

Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
---
drivers/hwmon/pmbus/pmbus.h | 2 +-
drivers/hwmon/pmbus/pmbus_core.c | 151 ++++++++++++++++++++++++++++---
2 files changed, 137 insertions(+), 16 deletions(-)

diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
index 10fb17879f8e..6b2e6cf93b19 100644
--- a/drivers/hwmon/pmbus/pmbus.h
+++ b/drivers/hwmon/pmbus/pmbus.h
@@ -26,7 +26,7 @@ enum pmbus_regs {

PMBUS_CAPABILITY = 0x19,
PMBUS_QUERY = 0x1A,
-
+ PMBUS_SMBALERT_MASK = 0x1B,
PMBUS_VOUT_MODE = 0x20,
PMBUS_VOUT_COMMAND = 0x21,
PMBUS_VOUT_TRIM = 0x22,
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 060e9d0a55bd..e1f84fa127ba 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -81,6 +81,7 @@ struct pmbus_label {
struct pmbus_data {
struct device *dev;
struct device *hwmon_dev;
+ struct regulator_dev **rdevs;

u32 flags; /* from platform data */

@@ -2823,7 +2824,8 @@ static const struct pmbus_regulator_status_category pmbus_regulator_flag_map[] =
},
};

-static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags)
+static int pmbus_regulator_get_flags(struct regulator_dev *rdev, unsigned int *error,
+ unsigned int *event)
{
int i, status;
const struct pmbus_regulator_status_category *cat;
@@ -2834,7 +2836,8 @@ static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned
u8 page = rdev_get_id(rdev);
int func = data->info->func[page];

- *flags = 0;
+ *error = 0;
+ *event = 0;

mutex_lock(&data->update_lock);

@@ -2850,8 +2853,10 @@ static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned
}

for (bit = cat->bits; bit->pflag; bit++) {
- if (status & bit->pflag)
- *flags |= bit->rflag;
+ if (status & bit->pflag) {
+ *error |= bit->rflag;
+ *event |= bit->eflag;
+ }
}
}

@@ -2870,11 +2875,15 @@ static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned
return status;

if (pmbus_regulator_is_enabled(rdev)) {
- if (status & PB_STATUS_OFF)
- *flags |= REGULATOR_ERROR_FAIL;
+ if (status & PB_STATUS_OFF) {
+ *error |= REGULATOR_ERROR_FAIL;
+ *event |= REGULATOR_EVENT_FAIL;
+ }

- if (status & PB_STATUS_POWER_GOOD_N)
- *flags |= REGULATOR_ERROR_REGULATION_OUT;
+ if (status & PB_STATUS_POWER_GOOD_N) {
+ *error |= REGULATOR_ERROR_REGULATION_OUT;
+ *event |= REGULATOR_EVENT_REGULATION_OUT;
+ }
}

/*
@@ -2882,13 +2891,22 @@ static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned
* PMBUS_STATUS_TEMPERATURE, map PB_STATUS_TEMPERATURE to a warning as
* a (conservative) best-effort interpretation.
*/
- if (!(*flags & (REGULATOR_ERROR_OVER_TEMP | REGULATOR_ERROR_OVER_TEMP_WARN)) &&
- (status & PB_STATUS_TEMPERATURE))
- *flags |= REGULATOR_ERROR_OVER_TEMP_WARN;
+ if (!(*error & (REGULATOR_ERROR_OVER_TEMP | REGULATOR_ERROR_OVER_TEMP_WARN)) &&
+ (status & PB_STATUS_TEMPERATURE)) {
+ *error |= REGULATOR_ERROR_OVER_TEMP_WARN;
+ *event |= REGULATOR_EVENT_OVER_TEMP_WARN;
+ }

return 0;
}

+static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags)
+{
+ unsigned int event;
+
+ return pmbus_regulator_get_flags(rdev, flags, &event);
+}
+
static int pmbus_regulator_get_status(struct regulator_dev *rdev)
{
struct device *dev = rdev_get_dev(rdev);
@@ -3079,14 +3097,61 @@ const struct regulator_ops pmbus_regulator_ops = {
};
EXPORT_SYMBOL_NS_GPL(pmbus_regulator_ops, PMBUS);

+static int pmbus_write_smbalert_mask(struct i2c_client *client, u8 page, u8 reg, u8 val)
+{
+ return pmbus_write_word_data(client, page, PMBUS_SMBALERT_MASK, reg | (val << 8));
+}
+
+static irqreturn_t pmbus_fault_handler(int irq, void *pdata)
+{
+ struct pmbus_data *data = pdata;
+ struct i2c_client *client = to_i2c_client(data->dev);
+ int i, ret = IRQ_NONE, status, event;
+ u8 page;
+
+ for (i = 0; i < data->info->num_regulators; i++) {
+
+ if (!data->rdevs[i])
+ continue;
+
+ ret = pmbus_regulator_get_flags(data->rdevs[i], &status, &event);
+ if (ret)
+ return ret;
+
+ if (event) {
+ regulator_notifier_call_chain(data->rdevs[i], event, NULL);
+ ret = IRQ_HANDLED;
+ }
+
+ page = rdev_get_id(data->rdevs[i]);
+ mutex_lock(&data->update_lock);
+ status = pmbus_read_status_word(client, page);
+ if (status < 0) {
+ mutex_unlock(&data->update_lock);
+ return status;
+ }
+
+ if (status & ~(PB_STATUS_OFF | PB_STATUS_BUSY | PB_STATUS_POWER_GOOD_N))
+ pmbus_clear_fault_page(client, page);
+
+ mutex_unlock(&data->update_lock);
+ }
+
+ return ret;
+}
+
static int pmbus_regulator_register(struct pmbus_data *data)
{
struct device *dev = data->dev;
const struct pmbus_driver_info *info = data->info;
const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
- struct regulator_dev *rdev;
int i;

+ data->rdevs = devm_kzalloc(dev, sizeof(struct regulator_dev *) * info->num_regulators,
+ GFP_KERNEL);
+ if (!data->rdevs)
+ return -ENOMEM;
+
for (i = 0; i < info->num_regulators; i++) {
struct regulator_config config = { };

@@ -3096,21 +3161,71 @@ static int pmbus_regulator_register(struct pmbus_data *data)
if (pdata && pdata->reg_init_data)
config.init_data = &pdata->reg_init_data[i];

- rdev = devm_regulator_register(dev, &info->reg_desc[i],
+ data->rdevs[i] = devm_regulator_register(dev, &info->reg_desc[i],
&config);
- if (IS_ERR(rdev))
- return dev_err_probe(dev, PTR_ERR(rdev),
+ if (IS_ERR(data->rdevs[i]))
+ return dev_err_probe(dev, PTR_ERR(data->rdevs[i]),
"Failed to register %s regulator\n",
info->reg_desc[i].name);
}

return 0;
}
+
+static int pmbus_irq_setup(struct i2c_client *client, struct pmbus_data *data)
+{
+ struct device *dev = &client->dev;
+ const struct pmbus_regulator_status_category *cat;
+ const struct pmbus_regulator_status_assoc *bit;
+ int i, j, err, ret;
+ u8 mask;
+ int func;
+
+ for (i = 0; i < data->info->pages; i++) {
+ func = data->info->func[i];
+
+ for (j = 0; j < ARRAY_SIZE(pmbus_regulator_flag_map); j++) {
+ cat = &pmbus_regulator_flag_map[i];
+ if (!(func & cat->func))
+ continue;
+ mask = 0;
+ for (bit = cat->bits; bit->pflag; bit++)
+ mask |= bit->pflag;
+
+ err = pmbus_write_smbalert_mask(client, i, cat->reg, ~mask);
+ if (err)
+ dev_err(dev, "Failed to set smbalert for reg 0x%02x\n", cat->reg);
+ }
+
+ pmbus_write_smbalert_mask(client, i, PMBUS_STATUS_CML, 0xff);
+ pmbus_write_smbalert_mask(client, i, PMBUS_STATUS_OTHER, 0xff);
+ pmbus_write_smbalert_mask(client, i, PMBUS_STATUS_MFR_SPECIFIC, 0xff);
+ if (data->info->func[i] & PMBUS_HAVE_FAN12)
+ pmbus_write_smbalert_mask(client, i, PMBUS_STATUS_FAN_12, 0xff);
+ if (data->info->func[i] & PMBUS_HAVE_FAN34)
+ pmbus_write_smbalert_mask(client, i, PMBUS_STATUS_FAN_34, 0xff);
+
+ }
+
+ /* Register notifiers - can fail if IRQ is not given */
+ ret = devm_request_threaded_irq(dev, client->irq, NULL, pmbus_fault_handler,
+ 0, "pmbus-irq", data);
+ if (ret) {
+ dev_warn(dev, "IRQ disabled %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
#else
static int pmbus_regulator_register(struct pmbus_data *data)
{
return 0;
}
+static int pmbus_irq_setup(struct i2c_client *client, struct pmbus_data *data)
+{
+ return 0;
+}
#endif

static struct dentry *pmbus_debugfs_dir; /* pmbus debugfs directory */
@@ -3475,6 +3590,12 @@ int pmbus_do_probe(struct i2c_client *client, struct pmbus_driver_info *info)
if (ret)
return ret;

+ if (client->irq > 0) {
+ ret = pmbus_irq_setup(client, data);
+ if (ret)
+ return ret;
+ }
+
ret = pmbus_init_debugfs(client, data);
if (ret)
dev_warn(dev, "Failed to register debugfs\n");
--
2.37.3