[PATCH v2 1/2] hwmon: (pmbus) add a function to check the presence of a block register

[PATCH v2 1/2] hwmon: (pmbus) add a function to check the presence of a block register

[Adam Wujek]

Other functions (like pmbus_check_byte_register) cannot be used to check
the presence of a block register, because it will generate error when PEC
is used.

Signed-off-by: Adam Wujek <dev_public@wujek.eu>
---
Notes:
  Changes in v2:
    - Use Phase 0xff when setting the page

 drivers/hwmon/pmbus/pmbus_core.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index acf78d0829d9..2ff66f133d95 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -421,6 +421,18 @@ static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
 	return pmbus_read_byte_data(client, page, reg);
 }

+static int pmbus_read_block_data(struct i2c_client *client, int page, u8 reg,
+				 char *data_buf)
+{
+	int rv;
+
+	rv = pmbus_set_page(client, page, 0xff);
+	if (rv < 0)
+		return rv;
+
+	return i2c_smbus_read_block_data(client, reg, data_buf);
+}
+
 static struct pmbus_sensor *pmbus_find_sensor(struct pmbus_data *data, int page,
 					      int reg)
 {
@@ -558,6 +570,20 @@ bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
 }
 EXPORT_SYMBOL_NS_GPL(pmbus_check_word_register, PMBUS);

+static bool pmbus_check_block_register(struct i2c_client *client, int page,
+				       int reg)
+{
+	int rv;
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	char data_buf[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
+
+	rv = pmbus_read_block_data(client, page, reg, data_buf);
+	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
+		rv = pmbus_check_status_cml(client);
+	pmbus_clear_fault_page(client, -1);
+	return rv >= 0;
+}
+
 const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
 {
 	struct pmbus_data *data = i2c_get_clientdata(client);
--
2.17.1

[PATCH v2 2/2] hwmon: (pmbus) add MFR_* registers to debugfs

[Adam Wujek]

Add registers to debugfs:
PMBUS_MFR_ID
PMBUS_MFR_MODEL
PMBUS_MFR_REVISION
PMBUS_MFR_LOCATION
PMBUS_MFR_DATE
PMBUS_MFR_SERIAL

Please note that it is assumed that values of these registers are the same
for all pages. To reduce the number of debugfs entries, only values from
page 0 are reported.

Signed-off-by: Adam Wujek <dev_public@wujek.eu>
---
Notes:
- This is a reworked patch to report the registers only once

 drivers/hwmon/pmbus/pmbus_core.c | 100 ++++++++++++++++++++++++++++++-
 1 file changed, 98 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 2ff66f133d95..72411d30dd78 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -2657,6 +2657,34 @@ static int pmbus_debugfs_get_status(void *data, u64 *val)
 DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_status, pmbus_debugfs_get_status,
 			 NULL, "0x%04llx\n");

+static ssize_t pmbus_debugfs_mfr_read(struct file *file, char __user *buf,
+				       size_t count, loff_t *ppos)
+{
+	int rc;
+	struct pmbus_debugfs_entry *entry = file->private_data;
+	char data[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
+
+	rc = pmbus_read_block_data(entry->client, entry->page, entry->reg,
+				   data);
+	if (rc < 0)
+		return rc;
+
+	/* Add newline at the end of a read data */
+	data[rc] = '\n';
+
+	/* Include newline into the length */
+	rc += 1;
+
+	return simple_read_from_buffer(buf, count, ppos, data, rc);
+}
+
+static const struct file_operations pmbus_debugfs_ops_mfr = {
+	.llseek = noop_llseek,
+	.read = pmbus_debugfs_mfr_read,
+	.write = NULL,
+	.open = simple_open,
+};
+
 static int pmbus_debugfs_get_pec(void *data, u64 *val)
 {
 	struct i2c_client *client = data;
@@ -2721,9 +2749,13 @@ static int pmbus_init_debugfs(struct i2c_client *client,
 		return -ENODEV;
 	}

-	/* Allocate the max possible entries we need. */
+	/*
+	 * Allocate the max possible entries we need.
+	 * 6 entries device-specific
+	 * 10 entries page-specific
+	 */
 	entries = devm_kcalloc(data->dev,
-			       data->info->pages * 10, sizeof(*entries),
+			       6 + data->info->pages * 10, sizeof(*entries),
 			       GFP_KERNEL);
 	if (!entries)
 		return -ENOMEM;
@@ -2731,6 +2763,70 @@ static int pmbus_init_debugfs(struct i2c_client *client,
 	debugfs_create_file("pec", 0664, data->debugfs, client,
 			    &pmbus_debugfs_ops_pec);

+	/*
+	 * Add device-specific entries.
+	 * Please note that the PMBUS standard allows all registers to be
+	 * page-specific.
+	 * To reduce the number of debugfs entries for
+	 * devices with many pages assume that values of the following
+	 * registers are the same for all pages and report values only
+	 * for page 0.
+	 */
+	if (pmbus_check_block_register(client, 0, PMBUS_MFR_ID)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_MFR_ID;
+		debugfs_create_file("mfr_id", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops_mfr);
+	}
+
+	if (pmbus_check_block_register(client, 0, PMBUS_MFR_MODEL)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_MFR_MODEL;
+		debugfs_create_file("mfr_model", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops_mfr);
+	}
+
+	if (pmbus_check_block_register(client, 0, PMBUS_MFR_REVISION)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_MFR_REVISION;
+		debugfs_create_file("mfr_revision", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops_mfr);
+	}
+
+	if (pmbus_check_block_register(client, 0, PMBUS_MFR_LOCATION)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_MFR_LOCATION;
+		debugfs_create_file("mfr_location", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops_mfr);
+	}
+
+	if (pmbus_check_block_register(client, 0, PMBUS_MFR_DATE)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_MFR_DATE;
+		debugfs_create_file("mfr_date", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops_mfr);
+	}
+
+	if (pmbus_check_block_register(client, 0, PMBUS_MFR_SERIAL)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_MFR_SERIAL;
+		debugfs_create_file("mfr_serial", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops_mfr);
+	}
+
+	/* Add page specific entries */
 	for (i = 0; i < data->info->pages; ++i) {
 		/* Check accessibility of status register if it's not page 0 */
 		if (!i || pmbus_check_status_register(client, i)) {
--
2.17.1

Re: [PATCH v2 1/2] hwmon: (pmbus) add a function to check the presence of a block register

[Guenter Roeck]

On 5/24/22 03:43, Adam Wujek wrote:
> Other functions (like pmbus_check_byte_register) cannot be used to check
> the presence of a block register, because it will generate error when PEC
> is used.
> 
> Signed-off-by: Adam Wujek <dev_public@wujek.eu>
> ---
> Notes:
>    Changes in v2:
>      - Use Phase 0xff when setting the page
> 
>   drivers/hwmon/pmbus/pmbus_core.c | 26 ++++++++++++++++++++++++++
>   1 file changed, 26 insertions(+)
> 
> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
> index acf78d0829d9..2ff66f133d95 100644
> --- a/drivers/hwmon/pmbus/pmbus_core.c
> +++ b/drivers/hwmon/pmbus/pmbus_core.c
> @@ -421,6 +421,18 @@ static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
>   	return pmbus_read_byte_data(client, page, reg);
>   }
> 
> +static int pmbus_read_block_data(struct i2c_client *client, int page, u8 reg,
> +				 char *data_buf)
> +{
> +	int rv;
> +
> +	rv = pmbus_set_page(client, page, 0xff);
> +	if (rv < 0)
> +		return rv;
> +
> +	return i2c_smbus_read_block_data(client, reg, data_buf);
> +}
> +
>   static struct pmbus_sensor *pmbus_find_sensor(struct pmbus_data *data, int page,
>   					      int reg)
>   {
> @@ -558,6 +570,20 @@ bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
>   }
>   EXPORT_SYMBOL_NS_GPL(pmbus_check_word_register, PMBUS);
> 
> +static bool pmbus_check_block_register(struct i2c_client *client, int page,
> +				       int reg)
> +{
> +	int rv;
> +	struct pmbus_data *data = i2c_get_clientdata(client);
> +	char data_buf[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };

Unnecessary initialization.

> +
> +	rv = pmbus_read_block_data(client, page, reg, data_buf);
> +	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
> +		rv = pmbus_check_status_cml(client);

How about PMBUS_READ_STATUS_AFTER_FAILED_CHECK ?

Thanks,
Guenter

> +	pmbus_clear_fault_page(client, -1);
> +	return rv >= 0;
> +}
> +
>   const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
>   {
>   	struct pmbus_data *data = i2c_get_clientdata(client);
> --
> 2.17.1
> 
> 

Re: [PATCH v2 1/2] hwmon: (pmbus) add a function to check the presence of a block register

[wujek dev]

On Tuesday, May 24th, 2022 at 15:32, Guenter Roeck <linux@roeck-us.net> wrote:


>
>
> On 5/24/22 03:43, Adam Wujek wrote:
>
> > Other functions (like pmbus_check_byte_register) cannot be used to check
> > the presence of a block register, because it will generate error when PEC
> > is used.
> >
> > Signed-off-by: Adam Wujek dev_public@wujek.eu
> > ---
> > Notes:
> > Changes in v2:
> > - Use Phase 0xff when setting the page
> >
> > drivers/hwmon/pmbus/pmbus_core.c | 26 ++++++++++++++++++++++++++
> > 1 file changed, 26 insertions(+)
> >
> > diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
> > index acf78d0829d9..2ff66f133d95 100644
> > --- a/drivers/hwmon/pmbus/pmbus_core.c
> > +++ b/drivers/hwmon/pmbus/pmbus_core.c
> > @@ -421,6 +421,18 @@ static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
> > return pmbus_read_byte_data(client, page, reg);
> > }
> >
> > +static int pmbus_read_block_data(struct i2c_client *client, int page, u8 reg,
> > + char *data_buf)
> > +{
> > + int rv;
> > +
> > + rv = pmbus_set_page(client, page, 0xff);
> > + if (rv < 0)
> > + return rv;
> > +
> > + return i2c_smbus_read_block_data(client, reg, data_buf);
> > +}
> > +
> > static struct pmbus_sensor *pmbus_find_sensor(struct pmbus_data *data, int page,
> > int reg)
> > {
> > @@ -558,6 +570,20 @@ bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
> > }
> > EXPORT_SYMBOL_NS_GPL(pmbus_check_word_register, PMBUS);
> >
> > +static bool pmbus_check_block_register(struct i2c_client *client, int page,
> > + int reg)
> > +{
> > + int rv;
> > + struct pmbus_data *data = i2c_get_clientdata(client);
> > + char data_buf[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
>
>
> Unnecessary initialization.
Agree
>
> > +
> > + rv = pmbus_read_block_data(client, page, reg, data_buf);
> > + if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
> > + rv = pmbus_check_status_cml(client);
>
>
> How about PMBUS_READ_STATUS_AFTER_FAILED_CHECK ?
added in the next version
>
> Thanks,
> Guenter
BR,
Adam
>
> > + pmbus_clear_fault_page(client, -1);
> > + return rv >= 0;
> > +}
> > +
> > const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
> > {
> > struct pmbus_data *data = i2c_get_clientdata(client);
> > --
> > 2.17.1