Merge branch 'HWMON-support-for-SFP-modules'

Andrew Lunn says:

====================
HWMON support for SFP modules

This patchset adds HWMON support to SFP modules. The two patches add
some attributes for temperature and power sensors which are currently
missing from the hwmon core. The third patch adds a helper for
filtering out characters in hwmon names which are invalid. The last
patch then extends the core SFP code to export the sensors found in
SFP modules.

This code has been tested with two SFP modules:

module OEM SFP-7000-85 rev 11.0 sn M1512220075 dc 160221
module FINISAR CORP. FTLF8524E2GNL rev A sn PW40MNN dc 160725

The anonymous module uses external calibration, while the FINISAR uses
internal calibration. Thus both code paths have been tested.

Due to the cross subsystem nature of these patches, as discussed with
the RFC, it is hoped Guenter Roeck will ACK the patches, and then Dave
Miller will merge them all via net-next.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/hwmon/hwmon.c

@@ -394,12 +394,16 @@ static const char * const hwmon_power_attr_templates[] = {
 	[hwmon_power_cap_hyst] = "power%d_cap_hyst",
 	[hwmon_power_cap_max] = "power%d_cap_max",
 	[hwmon_power_cap_min] = "power%d_cap_min",
+	[hwmon_power_min] = "power%d_min",
 	[hwmon_power_max] = "power%d_max",
+	[hwmon_power_lcrit] = "power%d_lcrit",
 	[hwmon_power_crit] = "power%d_crit",
 	[hwmon_power_label] = "power%d_label",
 	[hwmon_power_alarm] = "power%d_alarm",
 	[hwmon_power_cap_alarm] = "power%d_cap_alarm",
+	[hwmon_power_min_alarm] = "power%d_min_alarm",
 	[hwmon_power_max_alarm] = "power%d_max_alarm",
+	[hwmon_power_lcrit_alarm] = "power%d_lcrit_alarm",
 	[hwmon_power_crit_alarm] = "power%d_crit_alarm",
 };
 

drivers/net/phy/Kconfig

@@ -215,6 +215,7 @@ config SFP
 	tristate "SFP cage support"
 	depends on I2C && PHYLINK
 	select MDIO_I2C
+	imply HWMON
 
 config AMD_PHY
 	tristate "AMD PHYs"

drivers/net/phy/sfp.c

+#include <linux/ctype.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
+#include <linux/hwmon.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/jiffies.h>
@@ -131,6 +133,12 @@ struct sfp {
 	unsigned int sm_retries;
 
 	struct sfp_eeprom_id id;
+#if IS_ENABLED(CONFIG_HWMON)
+	struct sfp_diag diag;
+	struct device *hwmon_dev;
+	char *hwmon_name;
+#endif
+
 };
 
 static bool sff_module_supported(const struct sfp_eeprom_id *id)
@@ -316,6 +324,719 @@ static unsigned int sfp_check(void *buf, size_t len)
 	return check;
 }
 
+/* hwmon */
+#if IS_ENABLED(CONFIG_HWMON)
+static umode_t sfp_hwmon_is_visible(const void *data,
+				    enum hwmon_sensor_types type,
+				    u32 attr, int channel)
+{
+	const struct sfp *sfp = data;
+
+	switch (type) {
+	case hwmon_temp:
+		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:
+		case hwmon_temp_min:
+		case hwmon_temp_max:
+		case hwmon_temp_lcrit:
+		case hwmon_temp_crit:
+			return 0444;
+		default:
+			return 0;
+		}
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_input:
+		case hwmon_in_min_alarm:
+		case hwmon_in_max_alarm:
+		case hwmon_in_lcrit_alarm:
+		case hwmon_in_crit_alarm:
+		case hwmon_in_min:
+		case hwmon_in_max:
+		case hwmon_in_lcrit:
+		case hwmon_in_crit:
+			return 0444;
+		default:
+			return 0;
+		}
+	case hwmon_curr:
+		switch (attr) {
+		case hwmon_curr_input:
+		case hwmon_curr_min_alarm:
+		case hwmon_curr_max_alarm:
+		case hwmon_curr_lcrit_alarm:
+		case hwmon_curr_crit_alarm:
+		case hwmon_curr_min:
+		case hwmon_curr_max:
+		case hwmon_curr_lcrit:
+		case hwmon_curr_crit:
+			return 0444;
+		default:
+			return 0;
+		}
+	case hwmon_power:
+		/* External calibration of receive power requires
+		 * floating point arithmetic. Doing that in the kernel
+		 * is not easy, so just skip it. If the module does
+		 * not require external calibration, we can however
+		 * show receiver power, since FP is then not needed.
+		 */
+		if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
+		    channel == 1)
+			return 0;
+		switch (attr) {
+		case hwmon_power_input:
+		case hwmon_power_min_alarm:
+		case hwmon_power_max_alarm:
+		case hwmon_power_lcrit_alarm:
+		case hwmon_power_crit_alarm:
+		case hwmon_power_min:
+		case hwmon_power_max:
+		case hwmon_power_lcrit:
+		case hwmon_power_crit:
+			return 0444;
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
+{
+	__be16 val;
+	int err;
+
+	err = sfp_read(sfp, true, reg, &val, sizeof(val));
+	if (err < 0)
+		return err;
+
+	*value = be16_to_cpu(val);
+
+	return 0;
+}
+
+static void sfp_hwmon_to_rx_power(long *value)
+{
+	*value = DIV_ROUND_CLOSEST(*value, 100);
+}
+
+static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
+				long *value)
+{
+	if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
+		*value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
+}
+
+static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
+{
+	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
+			    be16_to_cpu(sfp->diag.cal_t_offset), value);
+
+	if (*value >= 0x8000)
+		*value -= 0x10000;
+
+	*value = DIV_ROUND_CLOSEST(*value * 1000, 256);
+}
+
+static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
+{
+	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
+			    be16_to_cpu(sfp->diag.cal_v_offset), value);
+
+	*value = DIV_ROUND_CLOSEST(*value, 10);
+}
+
+static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
+{
+	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
+			    be16_to_cpu(sfp->diag.cal_txi_offset), value);
+
+	*value = DIV_ROUND_CLOSEST(*value, 500);
+}
+
+static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
+{
+	sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
+			    be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
+
+	*value = DIV_ROUND_CLOSEST(*value, 10);
+}
+
+static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
+{
+	int err;
+
+	err = sfp_hwmon_read_sensor(sfp, reg, value);
+	if (err < 0)
+		return err;
+
+	sfp_hwmon_calibrate_temp(sfp, value);
+
+	return 0;
+}
+
+static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
+{
+	int err;
+
+	err = sfp_hwmon_read_sensor(sfp, reg, value);
+	if (err < 0)
+		return err;
+
+	sfp_hwmon_calibrate_vcc(sfp, value);
+
+	return 0;
+}
+
+static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
+{
+	int err;
+
+	err = sfp_hwmon_read_sensor(sfp, reg, value);
+	if (err < 0)
+		return err;
+
+	sfp_hwmon_calibrate_bias(sfp, value);
+
+	return 0;
+}
+
+static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
+{
+	int err;
+
+	err = sfp_hwmon_read_sensor(sfp, reg, value);
+	if (err < 0)
+		return err;
+
+	sfp_hwmon_calibrate_tx_power(sfp, value);
+
+	return 0;
+}
+
+static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
+{
+	int err;
+
+	err = sfp_hwmon_read_sensor(sfp, reg, value);
+	if (err < 0)
+		return err;
+
+	sfp_hwmon_to_rx_power(value);
+
+	return 0;
+}
+
+static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
+{
+	u8 status;
+	int err;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
+
+	case hwmon_temp_lcrit:
+		*value = be16_to_cpu(sfp->diag.temp_low_alarm);
+		sfp_hwmon_calibrate_temp(sfp, value);
+		return 0;
+
+	case hwmon_temp_min:
+		*value = be16_to_cpu(sfp->diag.temp_low_warn);
+		sfp_hwmon_calibrate_temp(sfp, value);
+		return 0;
+	case hwmon_temp_max:
+		*value = be16_to_cpu(sfp->diag.temp_high_warn);
+		sfp_hwmon_calibrate_temp(sfp, value);
+		return 0;
+
+	case hwmon_temp_crit:
+		*value = be16_to_cpu(sfp->diag.temp_high_alarm);
+		sfp_hwmon_calibrate_temp(sfp, value);
+		return 0;
+
+	case hwmon_temp_lcrit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_TEMP_LOW);
+		return 0;
+
+	case hwmon_temp_min_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_TEMP_LOW);
+		return 0;
+
+	case hwmon_temp_max_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_TEMP_HIGH);
+		return 0;
+
+	case hwmon_temp_crit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_TEMP_HIGH);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
+{
+	u8 status;
+	int err;
+
+	switch (attr) {
+	case hwmon_in_input:
+		return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
+
+	case hwmon_in_lcrit:
+		*value = be16_to_cpu(sfp->diag.volt_low_alarm);
+		sfp_hwmon_calibrate_vcc(sfp, value);
+		return 0;
+
+	case hwmon_in_min:
+		*value = be16_to_cpu(sfp->diag.volt_low_warn);
+		sfp_hwmon_calibrate_vcc(sfp, value);
+		return 0;
+
+	case hwmon_in_max:
+		*value = be16_to_cpu(sfp->diag.volt_high_warn);
+		sfp_hwmon_calibrate_vcc(sfp, value);
+		return 0;
+
+	case hwmon_in_crit:
+		*value = be16_to_cpu(sfp->diag.volt_high_alarm);
+		sfp_hwmon_calibrate_vcc(sfp, value);
+		return 0;
+
+	case hwmon_in_lcrit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_VCC_LOW);
+		return 0;
+
+	case hwmon_in_min_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_VCC_LOW);
+		return 0;
+
+	case hwmon_in_max_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_VCC_HIGH);
+		return 0;
+
+	case hwmon_in_crit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_VCC_HIGH);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
+{
+	u8 status;
+	int err;
+
+	switch (attr) {
+	case hwmon_curr_input:
+		return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
+
+	case hwmon_curr_lcrit:
+		*value = be16_to_cpu(sfp->diag.bias_low_alarm);
+		sfp_hwmon_calibrate_bias(sfp, value);
+		return 0;
+
+	case hwmon_curr_min:
+		*value = be16_to_cpu(sfp->diag.bias_low_warn);
+		sfp_hwmon_calibrate_bias(sfp, value);
+		return 0;
+
+	case hwmon_curr_max:
+		*value = be16_to_cpu(sfp->diag.bias_high_warn);
+		sfp_hwmon_calibrate_bias(sfp, value);
+		return 0;
+
+	case hwmon_curr_crit:
+		*value = be16_to_cpu(sfp->diag.bias_high_alarm);
+		sfp_hwmon_calibrate_bias(sfp, value);
+		return 0;
+
+	case hwmon_curr_lcrit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
+		return 0;
+
+	case hwmon_curr_min_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_TX_BIAS_LOW);
+		return 0;
+
+	case hwmon_curr_max_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
+		return 0;
+
+	case hwmon_curr_crit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
+{
+	u8 status;
+	int err;
+
+	switch (attr) {
+	case hwmon_power_input:
+		return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
+
+	case hwmon_power_lcrit:
+		*value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
+		sfp_hwmon_calibrate_tx_power(sfp, value);
+		return 0;
+
+	case hwmon_power_min:
+		*value = be16_to_cpu(sfp->diag.txpwr_low_warn);
+		sfp_hwmon_calibrate_tx_power(sfp, value);
+		return 0;
+
+	case hwmon_power_max:
+		*value = be16_to_cpu(sfp->diag.txpwr_high_warn);
+		sfp_hwmon_calibrate_tx_power(sfp, value);
+		return 0;
+
+	case hwmon_power_crit:
+		*value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
+		sfp_hwmon_calibrate_tx_power(sfp, value);
+		return 0;
+
+	case hwmon_power_lcrit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_TXPWR_LOW);
+		return 0;
+
+	case hwmon_power_min_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_TXPWR_LOW);
+		return 0;
+
+	case hwmon_power_max_alarm:
+		err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN0_TXPWR_HIGH);
+		return 0;
+
+	case hwmon_power_crit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM0_TXPWR_HIGH);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
+{
+	u8 status;
+	int err;
+
+	switch (attr) {
+	case hwmon_power_input:
+		return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
+
+	case hwmon_power_lcrit:
+		*value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
+		sfp_hwmon_to_rx_power(value);
+		return 0;
+
+	case hwmon_power_min:
+		*value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
+		sfp_hwmon_to_rx_power(value);
+		return 0;
+
+	case hwmon_power_max:
+		*value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
+		sfp_hwmon_to_rx_power(value);
+		return 0;
+
+	case hwmon_power_crit:
+		*value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
+		sfp_hwmon_to_rx_power(value);
+		return 0;
+
+	case hwmon_power_lcrit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM1_RXPWR_LOW);
+		return 0;
+
+	case hwmon_power_min_alarm:
+		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN1_RXPWR_LOW);
+		return 0;
+
+	case hwmon_power_max_alarm:
+		err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_WARN1_RXPWR_HIGH);
+		return 0;
+
+	case hwmon_power_crit_alarm:
+		err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
+		if (err < 0)
+			return err;
+
+		*value = !!(status & SFP_ALARM1_RXPWR_HIGH);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			  u32 attr, int channel, long *value)
+{
+	struct sfp *sfp = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_temp:
+		return sfp_hwmon_temp(sfp, attr, value);
+	case hwmon_in:
+		return sfp_hwmon_vcc(sfp, attr, value);
+	case hwmon_curr:
+		return sfp_hwmon_bias(sfp, attr, value);
+	case hwmon_power:
+		switch (channel) {
+		case 0:
+			return sfp_hwmon_tx_power(sfp, attr, value);
+		case 1:
+			return sfp_hwmon_rx_power(sfp, attr, value);
+		default:
+			return -EOPNOTSUPP;
+		}
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static const struct hwmon_ops sfp_hwmon_ops = {
+	.is_visible = sfp_hwmon_is_visible,
+	.read = sfp_hwmon_read,
+};
+
+static u32 sfp_hwmon_chip_config[] = {
+	HWMON_C_REGISTER_TZ,
+	0,
+};
+
+static const struct hwmon_channel_info sfp_hwmon_chip = {
+	.type = hwmon_chip,
+	.config = sfp_hwmon_chip_config,
+};
+
+static u32 sfp_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 sfp_hwmon_temp_channel_info = {
+	.type = hwmon_temp,
+	.config = sfp_hwmon_temp_config,
+};
+
+static u32 sfp_hwmon_vcc_config[] = {
+	HWMON_I_INPUT |
+	HWMON_I_MAX | HWMON_I_MIN |
+	HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
+	HWMON_I_CRIT | HWMON_I_LCRIT |
+	HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM,
+	0,
+};
+
+static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
+	.type = hwmon_in,
+	.config = sfp_hwmon_vcc_config,
+};
+
+static u32 sfp_hwmon_bias_config[] = {
+	HWMON_C_INPUT |
+	HWMON_C_MAX | HWMON_C_MIN |
+	HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
+	HWMON_C_CRIT | HWMON_C_LCRIT |
+	HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM,
+	0,
+};
+
+static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
+	.type = hwmon_curr,
+	.config = sfp_hwmon_bias_config,
+};
+
+static u32 sfp_hwmon_power_config[] = {
+	/* Transmit power */
+	HWMON_P_INPUT |
+	HWMON_P_MAX | HWMON_P_MIN |
+	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
+	HWMON_P_CRIT | HWMON_P_LCRIT |
+	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM,
+	/* Receive power */
+	HWMON_P_INPUT |
+	HWMON_P_MAX | HWMON_P_MIN |
+	HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
+	HWMON_P_CRIT | HWMON_P_LCRIT |
+	HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM,
+	0,
+};
+
+static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
+	.type = hwmon_power,
+	.config = sfp_hwmon_power_config,
+};
+
+static const struct hwmon_channel_info *sfp_hwmon_info[] = {
+	&sfp_hwmon_chip,
+	&sfp_hwmon_vcc_channel_info,
+	&sfp_hwmon_temp_channel_info,
+	&sfp_hwmon_bias_channel_info,
+	&sfp_hwmon_power_channel_info,
+	NULL,
+};
+
+static const struct hwmon_chip_info sfp_hwmon_chip_info = {
+	.ops = &sfp_hwmon_ops,
+	.info = sfp_hwmon_info,
+};
+
+static int sfp_hwmon_insert(struct sfp *sfp)
+{
+	int err, i;
+
+	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
+		return 0;
+
+	if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
+		return 0;
+
+	if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
+		/* This driver in general does not support address
+		 * change.
+		 */
+		return 0;
+
+	err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
+	if (err < 0)
+		return err;
+
+	sfp->hwmon_name = kstrdup(dev_name(sfp->dev), GFP_KERNEL);
+	if (!sfp->hwmon_name)
+		return -ENODEV;
+
+	for (i = 0; sfp->hwmon_name[i]; i++)
+		if (hwmon_is_bad_char(sfp->hwmon_name[i]))
+			sfp->hwmon_name[i] = '_';
+
+	sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
+							 sfp->hwmon_name, sfp,
+							 &sfp_hwmon_chip_info,
+							 NULL);
+
+	return PTR_ERR_OR_ZERO(sfp->hwmon_dev);
+}
+
+static void sfp_hwmon_remove(struct sfp *sfp)
+{
+	hwmon_device_unregister(sfp->hwmon_dev);
+	kfree(sfp->hwmon_name);
+}
+#else
+static int sfp_hwmon_insert(struct sfp *sfp)
+{
+	return 0;
+}
+
+static void sfp_hwmon_remove(struct sfp *sfp)
+{
+}
+#endif
+
 /* Helpers */
 static void sfp_module_tx_disable(struct sfp *sfp)
 {
@@ -636,6 +1357,10 @@ static int sfp_sm_mod_probe(struct sfp *sfp)
 		dev_warn(sfp->dev,
 			 "module address swap to access page 0xA2 is not supported.\n");
 
+	ret = sfp_hwmon_insert(sfp);
+	if (ret < 0)
+		return ret;
+
 	ret = sfp_module_insert(sfp->sfp_bus, &sfp->id);
 	if (ret < 0)
 		return ret;
@@ -647,6 +1372,8 @@ static void sfp_sm_mod_remove(struct sfp *sfp)
 {
 	sfp_module_remove(sfp->sfp_bus);
 
+	sfp_hwmon_remove(sfp);
+
 	if (sfp->mod_phy)
 		sfp_sm_phy_detach(sfp);
 

include/linux/hwmon.h

@@ -93,6 +93,7 @@ enum hwmon_temp_attributes {
 #define HWMON_T_MIN_ALARM	BIT(hwmon_temp_min_alarm)
 #define HWMON_T_MAX_ALARM	BIT(hwmon_temp_max_alarm)
 #define HWMON_T_CRIT_ALARM	BIT(hwmon_temp_crit_alarm)
+#define HWMON_T_LCRIT_ALARM	BIT(hwmon_temp_lcrit_alarm)
 #define HWMON_T_EMERGENCY_ALARM	BIT(hwmon_temp_emergency_alarm)
 #define HWMON_T_FAULT		BIT(hwmon_temp_fault)
 #define HWMON_T_OFFSET		BIT(hwmon_temp_offset)
@@ -187,12 +188,16 @@ enum hwmon_power_attributes {
 	hwmon_power_cap_hyst,
 	hwmon_power_cap_max,
 	hwmon_power_cap_min,
+	hwmon_power_min,
 	hwmon_power_max,
 	hwmon_power_crit,
+	hwmon_power_lcrit,
 	hwmon_power_label,
 	hwmon_power_alarm,
 	hwmon_power_cap_alarm,
+	hwmon_power_min_alarm,
 	hwmon_power_max_alarm,
+	hwmon_power_lcrit_alarm,
 	hwmon_power_crit_alarm,
 };
 
@@ -213,12 +218,16 @@ enum hwmon_power_attributes {
 #define HWMON_P_CAP_HYST		BIT(hwmon_power_cap_hyst)
 #define HWMON_P_CAP_MAX			BIT(hwmon_power_cap_max)
 #define HWMON_P_CAP_MIN			BIT(hwmon_power_cap_min)
+#define HWMON_P_MIN			BIT(hwmon_power_min)
 #define HWMON_P_MAX			BIT(hwmon_power_max)
+#define HWMON_P_LCRIT			BIT(hwmon_power_lcrit)
 #define HWMON_P_CRIT			BIT(hwmon_power_crit)
 #define HWMON_P_LABEL			BIT(hwmon_power_label)
 #define HWMON_P_ALARM			BIT(hwmon_power_alarm)
 #define HWMON_P_CAP_ALARM		BIT(hwmon_power_cap_alarm)
+#define HWMON_P_MIN_ALARM		BIT(hwmon_power_max_alarm)
 #define HWMON_P_MAX_ALARM		BIT(hwmon_power_max_alarm)
+#define HWMON_P_LCRIT_ALARM		BIT(hwmon_power_lcrit_alarm)
 #define HWMON_P_CRIT_ALARM		BIT(hwmon_power_crit_alarm)
 
 enum hwmon_energy_attributes {
@@ -389,4 +398,27 @@ devm_hwmon_device_register_with_info(struct device *dev,
 void hwmon_device_unregister(struct device *dev);
 void devm_hwmon_device_unregister(struct device *dev);
 
+/**
+ * hwmon_is_bad_char - Is the char invalid in a hwmon name
+ * @ch: the char to be considered
+ *
+ * hwmon_is_bad_char() can be used to determine if the given character
+ * may not be used in a hwmon name.
+ *
+ * Returns true if the char is invalid, false otherwise.
+ */
+static inline bool hwmon_is_bad_char(const char ch)
+{
+	switch (ch) {
+	case '-':
+	case '*':
+	case ' ':
+	case '\t':
+	case '\n':
+		return true;
+	default:
+		return false;
+	}
+}
+
 #endif

include/linux/sfp.h

@@ -231,6 +231,50 @@ struct sfp_eeprom_id {
 	struct sfp_eeprom_ext ext;
 } __packed;
 
+struct sfp_diag {
+	__be16 temp_high_alarm;
+	__be16 temp_low_alarm;
+	__be16 temp_high_warn;
+	__be16 temp_low_warn;
+	__be16 volt_high_alarm;
+	__be16 volt_low_alarm;
+	__be16 volt_high_warn;
+	__be16 volt_low_warn;
+	__be16 bias_high_alarm;
+	__be16 bias_low_alarm;
+	__be16 bias_high_warn;
+	__be16 bias_low_warn;
+	__be16 txpwr_high_alarm;
+	__be16 txpwr_low_alarm;
+	__be16 txpwr_high_warn;
+	__be16 txpwr_low_warn;
+	__be16 rxpwr_high_alarm;
+	__be16 rxpwr_low_alarm;
+	__be16 rxpwr_high_warn;
+	__be16 rxpwr_low_warn;
+	__be16 laser_temp_high_alarm;
+	__be16 laser_temp_low_alarm;
+	__be16 laser_temp_high_warn;
+	__be16 laser_temp_low_warn;
+	__be16 tec_cur_high_alarm;
+	__be16 tec_cur_low_alarm;
+	__be16 tec_cur_high_warn;
+	__be16 tec_cur_low_warn;
+	__be32 cal_rxpwr4;
+	__be32 cal_rxpwr3;
+	__be32 cal_rxpwr2;
+	__be32 cal_rxpwr1;
+	__be32 cal_rxpwr0;
+	__be16 cal_txi_slope;
+	__be16 cal_txi_offset;
+	__be16 cal_txpwr_slope;
+	__be16 cal_txpwr_offset;
+	__be16 cal_t_slope;
+	__be16 cal_t_offset;
+	__be16 cal_v_slope;
+	__be16 cal_v_offset;
+} __packed;
+
 /* SFP EEPROM registers */
 enum {
 	SFP_PHYS_ID			= 0x00,
@@ -384,7 +428,33 @@ enum {
 	SFP_TEC_CUR			= 0x6c,
 
 	SFP_STATUS			= 0x6e,
-	SFP_ALARM			= 0x70,
+	SFP_ALARM0			= 0x70,
+	SFP_ALARM0_TEMP_HIGH		= BIT(7),
+	SFP_ALARM0_TEMP_LOW		= BIT(6),
+	SFP_ALARM0_VCC_HIGH		= BIT(5),
+	SFP_ALARM0_VCC_LOW		= BIT(4),
+	SFP_ALARM0_TX_BIAS_HIGH		= BIT(3),
+	SFP_ALARM0_TX_BIAS_LOW		= BIT(2),
+	SFP_ALARM0_TXPWR_HIGH		= BIT(1),
+	SFP_ALARM0_TXPWR_LOW		= BIT(0),
+
+	SFP_ALARM1			= 0x71,
+	SFP_ALARM1_RXPWR_HIGH		= BIT(7),
+	SFP_ALARM1_RXPWR_LOW		= BIT(6),
+
+	SFP_WARN0			= 0x74,
+	SFP_WARN0_TEMP_HIGH		= BIT(7),
+	SFP_WARN0_TEMP_LOW		= BIT(6),
+	SFP_WARN0_VCC_HIGH		= BIT(5),
+	SFP_WARN0_VCC_LOW		= BIT(4),
+	SFP_WARN0_TX_BIAS_HIGH		= BIT(3),
+	SFP_WARN0_TX_BIAS_LOW		= BIT(2),
+	SFP_WARN0_TXPWR_HIGH		= BIT(1),
+	SFP_WARN0_TXPWR_LOW		= BIT(0),
+
+	SFP_WARN1			= 0x75,
+	SFP_WARN1_RXPWR_HIGH		= BIT(7),
+	SFP_WARN1_RXPWR_LOW		= BIT(6),
 
 	SFP_EXT_STATUS			= 0x76,
 	SFP_VSL				= 0x78,