[PATCH net-next v2 0/2] net: phy: aquantia: add hwmon support

[PATCH net-next v2 0/2] net: phy: aquantia: add hwmon support

[Heiner Kallweit]

This series adds HWMON support for the temperature sensor and the
related alarms on the 107/108/109 chips.

v2:
- remove struct aqr_priv
- rename header file to aquantia.h

Heiner Kallweit (2):
  net: phy: aquantia: rename aquantia.c to aquantia_main.c
  net: phy: aquantia: add hwmon support

 drivers/net/phy/Makefile                      |   1 +
 drivers/net/phy/aquantia.h                    |  16 ++
 drivers/net/phy/aquantia_hwmon.c              | 245 ++++++++++++++++++
 .../net/phy/{aquantia.c => aquantia_main.c}   |   4 +
 4 files changed, 266 insertions(+)
 create mode 100644 drivers/net/phy/aquantia.h
 create mode 100644 drivers/net/phy/aquantia_hwmon.c
 rename drivers/net/phy/{aquantia.c => aquantia_main.c} (99%)

-- 
2.20.1

[PATCH net-next v2 1/2] net: phy: aquantia: rename aquantia.c to aquantia_main.c

[Heiner Kallweit]

Rename aquantia.c to aquantia_main.c to be prepared for adding new
functionality to separate source code files.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/Makefile                        | 1 +
 drivers/net/phy/{aquantia.c => aquantia_main.c} | 0
 2 files changed, 1 insertion(+)
 rename drivers/net/phy/{aquantia.c => aquantia_main.c} (100%)

diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 5805c0b7d..b0845adaf 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -45,6 +45,7 @@ sfp-obj-$(CONFIG_SFP)		+= sfp-bus.o
 obj-y				+= $(sfp-obj-y) $(sfp-obj-m)
 
 obj-$(CONFIG_AMD_PHY)		+= amd.o
+aquantia-objs			+= aquantia_main.o
 obj-$(CONFIG_AQUANTIA_PHY)	+= aquantia.o
 obj-$(CONFIG_ASIX_PHY)		+= asix.o
 obj-$(CONFIG_AT803X_PHY)	+= at803x.o
diff --git a/drivers/net/phy/aquantia.c b/drivers/net/phy/aquantia_main.c
similarity index 100%
rename from drivers/net/phy/aquantia.c
rename to drivers/net/phy/aquantia_main.c
-- 
2.20.1

[PATCH net-next v2 2/2] net: phy: aquantia: add hwmon support

[Heiner Kallweit]

This adds HWMON support for the temperature sensor and the related
alarms on the 107/108/109 chips. This patch is based on work from
Nikita and Andrew. I added:
- support for changing alarm thresholds via sysfs
- move HWMON code to a separate source file to improve maintainability
- smaller changes like using IS_REACHABLE instead of ifdef
  (avoids problems if PHY driver is built in and HWMON is a module)

v2:
- remove struct aqr_priv
- rename header file to aquantia.h

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/Makefile         |   2 +-
 drivers/net/phy/aquantia.h       |  16 ++
 drivers/net/phy/aquantia_hwmon.c | 245 +++++++++++++++++++++++++++++++
 drivers/net/phy/aquantia_main.c  |   4 +
 4 files changed, 266 insertions(+), 1 deletion(-)
 create mode 100644 drivers/net/phy/aquantia.h
 create mode 100644 drivers/net/phy/aquantia_hwmon.c

diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index b0845adaf..c48596626 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -45,7 +45,7 @@ sfp-obj-$(CONFIG_SFP)		+= sfp-bus.o
 obj-y				+= $(sfp-obj-y) $(sfp-obj-m)
 
 obj-$(CONFIG_AMD_PHY)		+= amd.o
-aquantia-objs			+= aquantia_main.o
+aquantia-objs			+= aquantia_main.o aquantia_hwmon.o
 obj-$(CONFIG_AQUANTIA_PHY)	+= aquantia.o
 obj-$(CONFIG_ASIX_PHY)		+= asix.o
 obj-$(CONFIG_AT803X_PHY)	+= at803x.o
diff --git a/drivers/net/phy/aquantia.h b/drivers/net/phy/aquantia.h
new file mode 100644
index 000000000..5a16caab7
--- /dev/null
+++ b/drivers/net/phy/aquantia.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0
+ * HWMON driver for Aquantia PHY
+ *
+ * Author: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
+ * Author: Andrew Lunn <andrew@lunn.ch>
+ * Author: Heiner Kallweit <hkallweit1@gmail.com>
+ */
+
+#include <linux/device.h>
+#include <linux/phy.h>
+
+#if IS_REACHABLE(CONFIG_HWMON)
+int aqr_hwmon_probe(struct phy_device *phydev);
+#else
+static inline int aqr_hwmon_probe(struct phy_device *phydev) { return 0; }
+#endif
diff --git a/drivers/net/phy/aquantia_hwmon.c b/drivers/net/phy/aquantia_hwmon.c
new file mode 100644
index 000000000..9c77d149e
--- /dev/null
+++ b/drivers/net/phy/aquantia_hwmon.c
@@ -0,0 +1,245 @@
+// SPDX-License-Identifier: GPL-2.0
+/* HWMON driver for Aquantia PHY
+ *
+ * Author: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
+ * Author: Andrew Lunn <andrew@lunn.ch>
+ * Author: Heiner Kallweit <hkallweit1@gmail.com>
+ */
+
+#include <linux/phy.h>
+#include <linux/device.h>
+#include <linux/ctype.h>
+#include <linux/hwmon.h>
+
+#include "aquantia.h"
+
+/* Vendor specific 1, MDIO_MMD_VEND2 */
+#define VEND1_THERMAL_PROV_HIGH_TEMP_FAIL	0xc421
+#define VEND1_THERMAL_PROV_LOW_TEMP_FAIL	0xc422
+#define VEND1_THERMAL_PROV_HIGH_TEMP_WARN	0xc423
+#define VEND1_THERMAL_PROV_LOW_TEMP_WARN	0xc424
+#define VEND1_THERMAL_STAT1			0xc820
+#define VEND1_THERMAL_STAT2			0xc821
+#define VEND1_THERMAL_STAT2_VALID		BIT(0)
+#define VEND1_GENERAL_STAT1			0xc830
+#define VEND1_GENERAL_STAT1_HIGH_TEMP_FAIL	BIT(14)
+#define VEND1_GENERAL_STAT1_LOW_TEMP_FAIL	BIT(13)
+#define VEND1_GENERAL_STAT1_HIGH_TEMP_WARN	BIT(12)
+#define VEND1_GENERAL_STAT1_LOW_TEMP_WARN	BIT(11)
+
+#if IS_REACHABLE(CONFIG_HWMON)
+
+static umode_t aqr_hwmon_is_visible(const void *data,
+				    enum hwmon_sensor_types type,
+				    u32 attr, int channel)
+{
+	if (type != hwmon_temp)
+		return 0;
+
+	switch (attr) {
+	case hwmon_temp_input:
+	case hwmon_temp_min_alarm:
+	case hwmon_temp_max_alarm:
+	case hwmon_temp_lcrit_alarm:
+	case hwmon_temp_crit_alarm:
+		return 0444;
+	case hwmon_temp_min:
+	case hwmon_temp_max:
+	case hwmon_temp_lcrit:
+	case hwmon_temp_crit:
+		return 0644;
+	default:
+		return 0;
+	}
+}
+
+static int aqr_hwmon_get(struct phy_device *phydev, int reg, long *value)
+{
+	int temp = phy_read_mmd(phydev, MDIO_MMD_VEND1, reg);
+
+	if (temp < 0)
+		return temp;
+
+	/* register value is 2's complement with LSB = 1/256th degree Celsius */
+	if (temp > 0x8000)
+		temp -= 0x10000;
+
+	*value = temp * 1000 / 256;
+
+	return 0;
+}
+
+static int aqr_hwmon_set(struct phy_device *phydev, int reg, long value)
+{
+	int temp;
+
+	if (value >= 128000 || value < -128000)
+		return -ERANGE;
+
+	temp = value * 256 / 1000;
+
+	if (temp < 0)
+		temp += 0x10000;
+
+	return phy_write_mmd(phydev, MDIO_MMD_VEND1, reg, temp);
+}
+
+static int aqr_hwmon_status1(struct phy_device *phydev, int bit, long *value)
+{
+	int reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, VEND1_GENERAL_STAT1);
+
+	if (reg < 0)
+		return reg;
+
+	*value = !!(reg & bit);
+
+	return 0;
+}
+
+static int aqr_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			  u32 attr, int channel, long *value)
+{
+	struct phy_device *phydev = dev_get_drvdata(dev);
+	int reg;
+
+	if (type != hwmon_temp)
+		return -EOPNOTSUPP;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		reg = phy_read_mmd(phydev, MDIO_MMD_VEND1,
+				   VEND1_THERMAL_STAT2);
+		if (reg < 0)
+			return reg;
+		if (!(reg & VEND1_THERMAL_STAT2_VALID))
+			return -EIO;
+
+		return aqr_hwmon_get(phydev, VEND1_THERMAL_STAT1, value);
+
+	case hwmon_temp_lcrit:
+		return aqr_hwmon_get(phydev, VEND1_THERMAL_PROV_LOW_TEMP_FAIL,
+				     value);
+	case hwmon_temp_min:
+		return aqr_hwmon_get(phydev, VEND1_THERMAL_PROV_LOW_TEMP_WARN,
+				     value);
+	case hwmon_temp_max:
+		return aqr_hwmon_get(phydev, VEND1_THERMAL_PROV_HIGH_TEMP_WARN,
+				     value);
+	case hwmon_temp_crit:
+		return aqr_hwmon_get(phydev, VEND1_THERMAL_PROV_HIGH_TEMP_FAIL,
+				     value);
+	case hwmon_temp_lcrit_alarm:
+		return aqr_hwmon_status1(phydev,
+					 VEND1_GENERAL_STAT1_LOW_TEMP_FAIL,
+					 value);
+	case hwmon_temp_min_alarm:
+		return aqr_hwmon_status1(phydev,
+					 VEND1_GENERAL_STAT1_LOW_TEMP_WARN,
+					 value);
+	case hwmon_temp_max_alarm:
+		return aqr_hwmon_status1(phydev,
+					 VEND1_GENERAL_STAT1_HIGH_TEMP_WARN,
+					 value);
+	case hwmon_temp_crit_alarm:
+		return aqr_hwmon_status1(phydev,
+					 VEND1_GENERAL_STAT1_HIGH_TEMP_FAIL,
+					 value);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int aqr_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
+			   u32 attr, int channel, long value)
+{
+	struct phy_device *phydev = dev_get_drvdata(dev);
+
+	if (type != hwmon_temp)
+		return -EOPNOTSUPP;
+
+	switch (attr) {
+	case hwmon_temp_lcrit:
+		return aqr_hwmon_set(phydev, VEND1_THERMAL_PROV_LOW_TEMP_FAIL,
+				     value);
+	case hwmon_temp_min:
+		return aqr_hwmon_set(phydev, VEND1_THERMAL_PROV_LOW_TEMP_WARN,
+				     value);
+	case hwmon_temp_max:
+		return aqr_hwmon_set(phydev, VEND1_THERMAL_PROV_HIGH_TEMP_WARN,
+				     value);
+	case hwmon_temp_crit:
+		return aqr_hwmon_set(phydev, VEND1_THERMAL_PROV_HIGH_TEMP_FAIL,
+				     value);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static const struct hwmon_ops aqr_hwmon_ops = {
+	.is_visible = aqr_hwmon_is_visible,
+	.read = aqr_hwmon_read,
+	.write = aqr_hwmon_write,
+};
+
+static u32 aqr_hwmon_chip_config[] = {
+	HWMON_C_REGISTER_TZ,
+	0,
+};
+
+static const struct hwmon_channel_info aqr_hwmon_chip = {
+	.type = hwmon_chip,
+	.config = aqr_hwmon_chip_config,
+};
+
+static u32 aqr_hwmon_temp_config[] = {
+	HWMON_T_INPUT |
+	HWMON_T_MAX | HWMON_T_MIN |
+	HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
+	HWMON_T_CRIT | HWMON_T_LCRIT |
+	HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM,
+	0,
+};
+
+static const struct hwmon_channel_info aqr_hwmon_temp = {
+	.type = hwmon_temp,
+	.config = aqr_hwmon_temp_config,
+};
+
+static const struct hwmon_channel_info *aqr_hwmon_info[] = {
+	&aqr_hwmon_chip,
+	&aqr_hwmon_temp,
+	NULL,
+};
+
+static const struct hwmon_chip_info aqr_hwmon_chip_info = {
+	.ops = &aqr_hwmon_ops,
+	.info = aqr_hwmon_info,
+};
+
+int aqr_hwmon_probe(struct phy_device *phydev)
+{
+	struct device *dev = &phydev->mdio.dev;
+	struct device *hwmon_dev;
+	char *hwmon_name;
+	int i, j;
+
+	hwmon_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+	if (!hwmon_name)
+		return -ENOMEM;
+
+	for (i = j = 0; hwmon_name[i]; i++) {
+		if (isalnum(hwmon_name[i])) {
+			if (i != j)
+				hwmon_name[j] = hwmon_name[i];
+			j++;
+		}
+	}
+	hwmon_name[j] = '\0';
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, hwmon_name,
+					phydev, &aqr_hwmon_chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+#endif
diff --git a/drivers/net/phy/aquantia_main.c b/drivers/net/phy/aquantia_main.c
index 0f0eb5682..37218e5d7 100644
--- a/drivers/net/phy/aquantia_main.c
+++ b/drivers/net/phy/aquantia_main.c
@@ -12,6 +12,8 @@
 #include <linux/delay.h>
 #include <linux/phy.h>
 
+#include "aquantia.h"
+
 #define PHY_ID_AQ1202	0x03a1b445
 #define PHY_ID_AQ2104	0x03a1b460
 #define PHY_ID_AQR105	0x03a1b4a2
@@ -231,6 +233,7 @@ static struct phy_driver aqr_driver[] = {
 	.name		= "Aquantia AQR107",
 	.aneg_done	= genphy_c45_aneg_done,
 	.get_features	= genphy_c45_pma_read_abilities,
+	.probe		= aqr_hwmon_probe,
 	.config_aneg    = aqr_config_aneg,
 	.config_intr	= aqr_config_intr,
 	.ack_interrupt	= aqr_ack_interrupt,
@@ -241,6 +244,7 @@ static struct phy_driver aqr_driver[] = {
 	.name		= "Aquantia AQCS109",
 	.aneg_done	= genphy_c45_aneg_done,
 	.get_features	= genphy_c45_pma_read_abilities,
+	.probe		= aqr_hwmon_probe,
 	.config_init	= aqcs109_config_init,
 	.config_aneg    = aqr_config_aneg,
 	.config_intr	= aqr_config_intr,
-- 
2.20.1

Re: [PATCH net-next v2 2/2] net: phy: aquantia: add hwmon support

[Florian Fainelli]

Le 2/24/19 à 1:36 PM, Heiner Kallweit a écrit :
> This adds HWMON support for the temperature sensor and the related
> alarms on the 107/108/109 chips. This patch is based on work from
> Nikita and Andrew. I added:
> - support for changing alarm thresholds via sysfs
> - move HWMON code to a separate source file to improve maintainability
> - smaller changes like using IS_REACHABLE instead of ifdef
>   (avoids problems if PHY driver is built in and HWMON is a module)
> 
> v2:
> - remove struct aqr_priv
> - rename header file to aquantia.h
> 
> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>

Should not Nikita be the author for that patch? Some minor nits below:

> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
>  drivers/net/phy/Makefile         |   2 +-
>  drivers/net/phy/aquantia.h       |  16 ++
>  drivers/net/phy/aquantia_hwmon.c | 245 +++++++++++++++++++++++++++++++
>  drivers/net/phy/aquantia_main.c  |   4 +
>  4 files changed, 266 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/net/phy/aquantia.h
>  create mode 100644 drivers/net/phy/aquantia_hwmon.c
> 
> diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
> index b0845adaf..c48596626 100644
> --- a/drivers/net/phy/Makefile
> +++ b/drivers/net/phy/Makefile
> @@ -45,7 +45,7 @@ sfp-obj-$(CONFIG_SFP)		+= sfp-bus.o
>  obj-y				+= $(sfp-obj-y) $(sfp-obj-m)
>  
>  obj-$(CONFIG_AMD_PHY)		+= amd.o
> -aquantia-objs			+= aquantia_main.o
> +aquantia-objs			+= aquantia_main.o aquantia_hwmon.o

Since you are adding a stub if CONFIG_HWMON is not reachable, does not
that mean you would want to do something like:

ifdef CONFIG_HWMON
aquanti-objs	+= aquantia_hwmon.o
endif

in this makefile?

[snip]

> +static int aqr_hwmon_get(struct phy_device *phydev, int reg, long *value)
> +{
> +	int temp = phy_read_mmd(phydev, MDIO_MMD_VEND1, reg);
> +
> +	if (temp < 0)
> +		return temp;
> +
> +	/* register value is 2's complement with LSB = 1/256th degree Celsius */
> +	if (temp > 0x8000)
> +		temp -= 0x10000;

Would decimal or BIT() notation be easier to use/read here?

> +
> +	*value = temp * 1000 / 256;
> +
> +	return 0;
> +}
> +
> +static int aqr_hwmon_set(struct phy_device *phydev, int reg, long value)
> +{
> +	int temp;
> +
> +	if (value >= 128000 || value < -128000)
> +		return -ERANGE;
> +
> +	temp = value * 256 / 1000;
> +
> +	if (temp < 0)
> +		temp += 0x10000;

Likewise

> +
> +	return phy_write_mmd(phydev, MDIO_MMD_VEND1, reg, temp);
> +}
> +
> +static int aqr_hwmon_status1(struct phy_device *phydev, int bit, long *value)
> +{
> +	int reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, VEND1_GENERAL_STAT1);
> +
> +	if (reg < 0)
> +		return reg;
> +
> +	*value = !!(reg & bit);
> +
> +	return 0;
> +}

Can you also make this function take a register offset as parameter such
that you can eliminate open coding that in the case hwmon_temp_input below?

> +
> +static int aqr_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
> +			  u32 attr, int channel, long *value)
> +{
> +	struct phy_device *phydev = dev_get_drvdata(dev);
> +	int reg;
> +
> +	if (type != hwmon_temp)
> +		return -EOPNOTSUPP;
> +
> +	switch (attr) {
> +	case hwmon_temp_input:
> +		reg = phy_read_mmd(phydev, MDIO_MMD_VEND1,
> +				   VEND1_THERMAL_STAT2);
> +		if (reg < 0)
> +			return reg;
> +		if (!(reg & VEND1_THERMAL_STAT2_VALID))
> +			return -EIO;

And use that helper here.

> +
> +		return aqr_hwmon_get(phydev, VEND1_THERMAL_STAT1, value);
> +

[snip]

> +	hwmon_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
> +	if (!hwmon_name)
> +		return -ENOMEM;
> +
> +	for (i = j = 0; hwmon_name[i]; i++) {
> +		if (isalnum(hwmon_name[i])) {
> +			if (i != j)
> +				hwmon_name[j] = hwmon_name[i];
> +			j++;
> +		}
> +	}
> +	hwmon_name[j] = '\0';

I am always baffled that drivers need to take care of these details...
but that seems to be the way to go.
-- 
Florian

Re: [PATCH net-next v2 2/2] net: phy: aquantia: add hwmon support

[Andrew Lunn]

On Sun, Feb 24, 2019 at 06:17:49PM -0800, Florian Fainelli wrote:
> Le 2/24/19 à 1:36 PM, Heiner Kallweit a écrit :
> > This adds HWMON support for the temperature sensor and the related
> > alarms on the 107/108/109 chips. This patch is based on work from
> > Nikita and Andrew. I added:
> > - support for changing alarm thresholds via sysfs
> > - move HWMON code to a separate source file to improve maintainability
> > - smaller changes like using IS_REACHABLE instead of ifdef
> >   (avoids problems if PHY driver is built in and HWMON is a module)
> > 
> > v2:
> > - remove struct aqr_priv
> > - rename header file to aquantia.h
> > 
> > Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> 
> Should not Nikita be the author for that patch? Some minor nits below:
> 
> > Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

Hi Florian

The history is convoluted. I did the initial implementation, but at
the time i did not have the hardware. So it got passed to Nikita who
did. He made it actually work, and passed patches back. I then passed
it onto Heiner who has done all the work on the driver and core for
C45.

	Andrew

Re: [PATCH net-next v2 2/2] net: phy: aquantia: add hwmon support

[Heiner Kallweit]

On 25.02.2019 03:17, Florian Fainelli wrote:
> Le 2/24/19 à 1:36 PM, Heiner Kallweit a écrit :
>> This adds HWMON support for the temperature sensor and the related
>> alarms on the 107/108/109 chips. This patch is based on work from
>> Nikita and Andrew. I added:
>> - support for changing alarm thresholds via sysfs
>> - move HWMON code to a separate source file to improve maintainability
>> - smaller changes like using IS_REACHABLE instead of ifdef
>>   (avoids problems if PHY driver is built in and HWMON is a module)
>>
>> v2:
>> - remove struct aqr_priv
>> - rename header file to aquantia.h
>>
>> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> 
> Should not Nikita be the author for that patch? Some minor nits below:
> 
>> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>> ---
>>  drivers/net/phy/Makefile         |   2 +-
>>  drivers/net/phy/aquantia.h       |  16 ++
>>  drivers/net/phy/aquantia_hwmon.c | 245 +++++++++++++++++++++++++++++++
>>  drivers/net/phy/aquantia_main.c  |   4 +
>>  4 files changed, 266 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/net/phy/aquantia.h
>>  create mode 100644 drivers/net/phy/aquantia_hwmon.c
>>
>> diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
>> index b0845adaf..c48596626 100644
>> --- a/drivers/net/phy/Makefile
>> +++ b/drivers/net/phy/Makefile
>> @@ -45,7 +45,7 @@ sfp-obj-$(CONFIG_SFP)		+= sfp-bus.o
>>  obj-y				+= $(sfp-obj-y) $(sfp-obj-m)
>>  
>>  obj-$(CONFIG_AMD_PHY)		+= amd.o
>> -aquantia-objs			+= aquantia_main.o
>> +aquantia-objs			+= aquantia_main.o aquantia_hwmon.o
> 
> Since you are adding a stub if CONFIG_HWMON is not reachable, does not
> that mean you would want to do something like:
> 
> ifdef CONFIG_HWMON
> aquanti-objs	+= aquantia_hwmon.o
> endif
> 
> in this makefile?
> 
Yepp, this should be changed as suggested by you.

> [snip]
> 
>> +static int aqr_hwmon_get(struct phy_device *phydev, int reg, long *value)
>> +{
>> +	int temp = phy_read_mmd(phydev, MDIO_MMD_VEND1, reg);
>> +
>> +	if (temp < 0)
>> +		return temp;
>> +
>> +	/* register value is 2's complement with LSB = 1/256th degree Celsius */
>> +	if (temp > 0x8000)
>> +		temp -= 0x10000;
> 
> Would decimal or BIT() notation be easier to use/read here?
> 
For the comparison I agree, we can write it as: if (temp & BIT(15))
And yes, the offset we could write decimal.

An alternative could be to write: temp = (s16)temp;
I tested it and it works, but I'm not sure whether this is covered
by C standard and works with all supported compilers.

>> +
>> +	*value = temp * 1000 / 256;
>> +
>> +	return 0;
>> +}
>> +
>> +static int aqr_hwmon_set(struct phy_device *phydev, int reg, long value)
>> +{
>> +	int temp;
>> +
>> +	if (value >= 128000 || value < -128000)
>> +		return -ERANGE;
>> +
>> +	temp = value * 256 / 1000;
>> +
>> +	if (temp < 0)
>> +		temp += 0x10000;
> 
> Likewise
> 
>> +
>> +	return phy_write_mmd(phydev, MDIO_MMD_VEND1, reg, temp);
>> +}
>> +
>> +static int aqr_hwmon_status1(struct phy_device *phydev, int bit, long *value)
>> +{
>> +	int reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, VEND1_GENERAL_STAT1);
>> +
>> +	if (reg < 0)
>> +		return reg;
>> +
>> +	*value = !!(reg & bit);
>> +
>> +	return 0;
>> +}
> 
> Can you also make this function take a register offset as parameter such
> that you can eliminate open coding that in the case hwmon_temp_input below?
> 
OK

>> +
>> +static int aqr_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
>> +			  u32 attr, int channel, long *value)
>> +{
>> +	struct phy_device *phydev = dev_get_drvdata(dev);
>> +	int reg;
>> +
>> +	if (type != hwmon_temp)
>> +		return -EOPNOTSUPP;
>> +
>> +	switch (attr) {
>> +	case hwmon_temp_input:
>> +		reg = phy_read_mmd(phydev, MDIO_MMD_VEND1,
>> +				   VEND1_THERMAL_STAT2);
>> +		if (reg < 0)
>> +			return reg;
>> +		if (!(reg & VEND1_THERMAL_STAT2_VALID))
>> +			return -EIO;
> 
> And use that helper here.
> 
>> +
>> +		return aqr_hwmon_get(phydev, VEND1_THERMAL_STAT1, value);
>> +
> 
> [snip]
> 
>> +	hwmon_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
>> +	if (!hwmon_name)
>> +		return -ENOMEM;
>> +
>> +	for (i = j = 0; hwmon_name[i]; i++) {
>> +		if (isalnum(hwmon_name[i])) {
>> +			if (i != j)
>> +				hwmon_name[j] = hwmon_name[i];
>> +			j++;
>> +		}
>> +	}
>> +	hwmon_name[j] = '\0';
> 
> I am always baffled that drivers need to take care of these details...
> but that seems to be the way to go.
> 
IIRC we still have a similar construction site in phylib.
If a PHY driver name includes e.g. a slash then sysfs is broken.
There should be a general helper e.g. in lib/string.c, because we have
this across subsystems wherever a device name is used in a sysfs path.