Re: [PATCH v3 3/4] hwmon: (pmbus/core): Implement irq support

[Naresh Solanki <naresh.solanki@9elements.com>]

Hi,

On 30-11-2022 11:54 pm, Guenter Roeck wrote:
> On Wed, Nov 30, 2022 at 05:59:53PM +0100, Naresh Solanki wrote:
>> From: Patrick Rudolph <patrick.rudolph@9elements.com>
>>
>> Implement PMBUS irq handler to notify regulator events.
>>
> 
> There should be separate patches for adding irq support, adding
> hwmon notifications, and adding regulator notifications. The order
> should be:
> 
> - Add interrupt support
> - Add hwmon notifications
> - Add events to regulator flag map
> - Add regulator notifications
Yes. Will do that as part of next revision. Thanks.

Naresh
> 
> Guenter
> 
>> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
>> Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
>> ---
>>   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 9a9e380acc23..613e2e484a0f 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 */
>>   
>> @@ -2804,7 +2805,8 @@ 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;
>> @@ -2815,7 +2817,8 @@ 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);
>>   
>> @@ -2831,8 +2834,10 @@ 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;
>> +			}
>>   		}
>>   	}
>>   
>> @@ -2851,11 +2856,15 @@ 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;
>> +		}
>>   	}
>>   
>>   	/*
>> @@ -2863,13 +2872,22 @@ 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);
>> @@ -3060,14 +3078,61 @@ 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 = { };
>>   
>> @@ -3077,21 +3142,71 @@ 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 */
>> @@ -3456,6 +3571,12 @@ 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
>>