[PATCH v4 3/4] hwmon: (pmbus/core): Add interrupt support

From: Naresh Solanki
Date: Wed Mar 01 2023 - 11:45:30 EST


From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>

Implement PMBUS irq handler.

Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
...
Changes in V4:
- Clear fault using pmbus_clear_faults at end of interrupt handler.
- Remove for loop.
Changes in V3:
- Remove pmbus word check for SMBALERT writes
- Remove variable ret & use err instead.
- Use dev_dbg_once instead of error.
- Remove error print when writing to misc_status register.
- Move client irq check to pmbus_irq_setup.
---
drivers/hwmon/pmbus/pmbus.h | 2 +-
drivers/hwmon/pmbus/pmbus_core.c | 70 ++++++++++++++++++++++++++++++++
2 files changed, 71 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
index 713ea7915425..11e84e141126 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 f8ac9016ea0e..dfd227459d8b 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -3105,6 +3105,72 @@ static int pmbus_regulator_register(struct pmbus_data *data)
}
#endif

+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);
+
+ mutex_lock(&data->update_lock);
+ /* TODO: Check status flag & notify hwmon events */
+
+ pmbus_clear_faults(client);
+ mutex_unlock(&data->update_lock);
+
+ return IRQ_HANDLED;
+}
+
+static int pmbus_irq_setup(struct i2c_client *client, struct pmbus_data *data)
+{
+ struct device *dev = &client->dev;
+ const struct pmbus_status_category *cat;
+ const struct pmbus_status_assoc *bit;
+ int i, j, err, func;
+ u8 mask;
+
+ static const u8 misc_status[] = {PMBUS_STATUS_CML, PMBUS_STATUS_OTHER,
+ PMBUS_STATUS_MFR_SPECIFIC, PMBUS_STATUS_FAN_12,
+ PMBUS_STATUS_FAN_34};
+
+ if (!client->irq)
+ return 0;
+
+ for (i = 0; i < data->info->pages; i++) {
+ func = data->info->func[i];
+
+ for (j = 0; j < ARRAY_SIZE(pmbus_status_flag_map); j++) {
+ cat = &pmbus_status_flag_map[j];
+ 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_dbg_once(dev, "Failed to set smbalert for reg 0x%02x\n",
+ cat->reg);
+ }
+
+ for (j = 0; j < ARRAY_SIZE(misc_status); j++)
+ pmbus_write_smbalert_mask(client, i, misc_status[j], 0xff);
+ }
+
+ /* Register notifiers */
+ err = devm_request_threaded_irq(dev, client->irq, NULL, pmbus_fault_handler, 0,
+ "pmbus-irq", data);
+ if (err) {
+ dev_err(dev, "failed to request an irq %d\n", err);
+ return err;
+ }
+
+ return 0;
+}
+
static struct dentry *pmbus_debugfs_dir; /* pmbus debugfs directory */

#if IS_ENABLED(CONFIG_DEBUG_FS)
@@ -3467,6 +3533,10 @@ int pmbus_do_probe(struct i2c_client *client, struct pmbus_driver_info *info)
if (ret)
return ret;

+ 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");
--
2.39.1