[PATCH net-next 0/4] SFP updates

[PATCH net-next 0/4] SFP updates

[Russell King - ARM Linux]

Included in this series are a further few updates for SFP support:

- Adding support for Fiberstore's non-standard BiDi modules operating
  at 1310nm/1550nm wavelengths rather than the 1000BASE-BX standard of
  1310nm/1490nm.
- Adding support for negotiating the PHY interface mode with the MAC,
  so that modules supporting faster speeds and Gigabit ethernet work
  with Gigabit-only MACs.
- Adding support for high power (>1W) SFP modules.

 Documentation/devicetree/bindings/net/sff,sfp.txt |   5 +
 drivers/net/phy/phylink.c                         |  33 +++--
 drivers/net/phy/sfp-bus.c                         | 162 ++++++++++------------
 drivers/net/phy/sfp.c                             | 150 +++++++++++++++++---
 include/linux/sfp.h                               |  18 +--
 5 files changed, 243 insertions(+), 125 deletions(-)

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
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[PATCH net-next 1/4] sfp: support 1G BiDi (eg, FiberStore SFP-GE-BX) modules

[Russell King]

Some BiDi modules (eg, FiberStore SFP-GE-BX) are not compliant with
1000BASE-BX as they use different wavelengths from the 1000BASE-BX
standard (eg, 1310nm/1550nm rather than 1310nm/1490nm).  These modules
support 1000BASE-X ethernet, so detect them by a failure to find any
other support, the 8B10B encoding and a bit rate that falls within the
1Gbps window.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/sfp-bus.c | 61 +++++++++++++++++++++++++++++------------------
 1 file changed, 38 insertions(+), 23 deletions(-)

diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index 8961209ee949..15749428679e 100644
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -180,10 +180,7 @@ void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 		       unsigned long *support)
 {
 	unsigned int br_min, br_nom, br_max;
-
-	phylink_set(support, Autoneg);
-	phylink_set(support, Pause);
-	phylink_set(support, Asym_Pause);
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(modes) = { 0, };
 
 	/* Decode the bitrate information to MBd */
 	br_min = br_nom = br_max = 0;
@@ -201,20 +198,20 @@ void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 
 	/* Set ethtool support from the compliance fields. */
 	if (id->base.e10g_base_sr)
-		phylink_set(support, 10000baseSR_Full);
+		phylink_set(modes, 10000baseSR_Full);
 	if (id->base.e10g_base_lr)
-		phylink_set(support, 10000baseLR_Full);
+		phylink_set(modes, 10000baseLR_Full);
 	if (id->base.e10g_base_lrm)
-		phylink_set(support, 10000baseLRM_Full);
+		phylink_set(modes, 10000baseLRM_Full);
 	if (id->base.e10g_base_er)
-		phylink_set(support, 10000baseER_Full);
+		phylink_set(modes, 10000baseER_Full);
 	if (id->base.e1000_base_sx ||
 	    id->base.e1000_base_lx ||
 	    id->base.e1000_base_cx)
-		phylink_set(support, 1000baseX_Full);
+		phylink_set(modes, 1000baseX_Full);
 	if (id->base.e1000_base_t) {
-		phylink_set(support, 1000baseT_Half);
-		phylink_set(support, 1000baseT_Full);
+		phylink_set(modes, 1000baseT_Half);
+		phylink_set(modes, 1000baseT_Full);
 	}
 
 	/* 1000Base-PX or 1000Base-BX10 */
@@ -228,20 +225,20 @@ void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 	if ((id->base.sfp_ct_passive || id->base.sfp_ct_active) && br_nom) {
 		/* This may look odd, but some manufacturers use 12000MBd */
 		if (br_min <= 12000 && br_max >= 10300)
-			phylink_set(support, 10000baseCR_Full);
+			phylink_set(modes, 10000baseCR_Full);
 		if (br_min <= 3200 && br_max >= 3100)
-			phylink_set(support, 2500baseX_Full);
+			phylink_set(modes, 2500baseX_Full);
 		if (br_min <= 1300 && br_max >= 1200)
-			phylink_set(support, 1000baseX_Full);
+			phylink_set(modes, 1000baseX_Full);
 	}
 	if (id->base.sfp_ct_passive) {
 		if (id->base.passive.sff8431_app_e)
-			phylink_set(support, 10000baseCR_Full);
+			phylink_set(modes, 10000baseCR_Full);
 	}
 	if (id->base.sfp_ct_active) {
 		if (id->base.active.sff8431_app_e ||
 		    id->base.active.sff8431_lim) {
-			phylink_set(support, 10000baseCR_Full);
+			phylink_set(modes, 10000baseCR_Full);
 		}
 	}
 
@@ -249,18 +246,18 @@ void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 	case 0x00: /* Unspecified */
 		break;
 	case 0x02: /* 100Gbase-SR4 or 25Gbase-SR */
-		phylink_set(support, 100000baseSR4_Full);
-		phylink_set(support, 25000baseSR_Full);
+		phylink_set(modes, 100000baseSR4_Full);
+		phylink_set(modes, 25000baseSR_Full);
 		break;
 	case 0x03: /* 100Gbase-LR4 or 25Gbase-LR */
 	case 0x04: /* 100Gbase-ER4 or 25Gbase-ER */
-		phylink_set(support, 100000baseLR4_ER4_Full);
+		phylink_set(modes, 100000baseLR4_ER4_Full);
 		break;
 	case 0x0b: /* 100Gbase-CR4 or 25Gbase-CR CA-L */
 	case 0x0c: /* 25Gbase-CR CA-S */
 	case 0x0d: /* 25Gbase-CR CA-N */
-		phylink_set(support, 100000baseCR4_Full);
-		phylink_set(support, 25000baseCR_Full);
+		phylink_set(modes, 100000baseCR4_Full);
+		phylink_set(modes, 25000baseCR_Full);
 		break;
 	default:
 		dev_warn(bus->sfp_dev,
@@ -274,10 +271,28 @@ void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 	    id->base.fc_speed_200 ||
 	    id->base.fc_speed_400) {
 		if (id->base.br_nominal >= 31)
-			phylink_set(support, 2500baseX_Full);
+			phylink_set(modes, 2500baseX_Full);
 		if (id->base.br_nominal >= 12)
-			phylink_set(support, 1000baseX_Full);
+			phylink_set(modes, 1000baseX_Full);
 	}
+
+	/* If we haven't discovered any modes that this module supports, try
+	 * the encoding and bitrate to determine supported modes. Some BiDi
+	 * modules (eg, 1310nm/1550nm) are not 1000BASE-BX compliant due to
+	 * the differing wavelengths, so do not set any transceiver bits.
+	 */
+	if (bitmap_empty(modes, __ETHTOOL_LINK_MODE_MASK_NBITS)) {
+		/* If the encoding and bit rate allows 1000baseX */
+		if (id->base.encoding == SFP_ENCODING_8B10B && br_nom &&
+		    br_min <= 1300 && br_max >= 1200)
+			phylink_set(modes, 1000baseX_Full);
+	}
+
+	bitmap_or(support, support, modes, __ETHTOOL_LINK_MODE_MASK_NBITS);
+
+	phylink_set(support, Autoneg);
+	phylink_set(support, Pause);
+	phylink_set(support, Asym_Pause);
 }
 EXPORT_SYMBOL_GPL(sfp_parse_support);
 
-- 
2.7.4

[PATCH net-next 2/4] phylink,sfp: negotiate interface format with MAC

[Russell King]

Negotiate the interface format with the MAC rather than requiring it to
be a fixed type specified solely by the SFP module.  This allows modules
that can work with several different interface signalling formats to
select a format compatible with the MAC - for example, a Fiber module
supporing Gigabit ethernet and faster connected to a Gigabit only MAC
needs to select the 1000BASE-X mode.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c |  33 ++++++++-------
 drivers/net/phy/sfp-bus.c | 101 ++++++++++++++++++----------------------------
 include/linux/sfp.h       |  18 +++++----
 3 files changed, 68 insertions(+), 84 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 6ac8b29b2dc3..27327c917a59 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1584,25 +1584,14 @@ static int phylink_sfp_module_insert(void *upstream,
 	bool changed;
 	u8 port;
 
-	sfp_parse_support(pl->sfp_bus, id, support);
-	port = sfp_parse_port(pl->sfp_bus, id, support);
-	iface = sfp_parse_interface(pl->sfp_bus, id);
-
 	ASSERT_RTNL();
 
-	switch (iface) {
-	case PHY_INTERFACE_MODE_SGMII:
-	case PHY_INTERFACE_MODE_1000BASEX:
-	case PHY_INTERFACE_MODE_2500BASEX:
-	case PHY_INTERFACE_MODE_10GKR:
-		break;
-	default:
-		return -EINVAL;
-	}
+	sfp_parse_support(pl->sfp_bus, id, support);
+	port = sfp_parse_port(pl->sfp_bus, id, support);
 
 	memset(&config, 0, sizeof(config));
 	linkmode_copy(config.advertising, support);
-	config.interface = iface;
+	config.interface = PHY_INTERFACE_MODE_NA;
 	config.speed = SPEED_UNKNOWN;
 	config.duplex = DUPLEX_UNKNOWN;
 	config.pause = MLO_PAUSE_AN;
@@ -1611,6 +1600,22 @@ static int phylink_sfp_module_insert(void *upstream,
 	/* Ignore errors if we're expecting a PHY to attach later */
 	ret = phylink_validate(pl, support, &config);
 	if (ret) {
+		netdev_err(pl->netdev, "validation with support %*pb failed: %d\n",
+			   __ETHTOOL_LINK_MODE_MASK_NBITS, support, ret);
+		return ret;
+	}
+
+	iface = sfp_select_interface(pl->sfp_bus, id, config.advertising);
+	if (iface == PHY_INTERFACE_MODE_NA) {
+		netdev_err(pl->netdev,
+			   "selection of interface failed, advertisment %*pb\n",
+			   __ETHTOOL_LINK_MODE_MASK_NBITS, config.advertising);
+		return -EINVAL;
+	}
+
+	config.interface = iface;
+	ret = phylink_validate(pl, support, &config);
+	if (ret) {
 		netdev_err(pl->netdev, "validation of %s/%s with support %*pb failed: %d\n",
 			   phylink_an_mode_str(MLO_AN_INBAND),
 			   phy_modes(config.interface),
diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index 15749428679e..3d4ff5d0d2a6 100644
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -106,68 +106,6 @@ int sfp_parse_port(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 EXPORT_SYMBOL_GPL(sfp_parse_port);
 
 /**
- * sfp_parse_interface() - Parse the phy_interface_t
- * @bus: a pointer to the &struct sfp_bus structure for the sfp module
- * @id: a pointer to the module's &struct sfp_eeprom_id
- *
- * Derive the phy_interface_t mode for the information found in the
- * module's identifying EEPROM. There is no standard or defined way
- * to derive this information, so we use some heuristics.
- *
- * If the encoding is 64b66b, then the module must be >= 10G, so
- * return %PHY_INTERFACE_MODE_10GKR.
- *
- * If it's 8b10b, then it's 1G or slower. If it's definitely a fibre
- * module, return %PHY_INTERFACE_MODE_1000BASEX mode, otherwise return
- * %PHY_INTERFACE_MODE_SGMII mode.
- *
- * If the encoding is not known, return %PHY_INTERFACE_MODE_NA.
- */
-phy_interface_t sfp_parse_interface(struct sfp_bus *bus,
-				    const struct sfp_eeprom_id *id)
-{
-	phy_interface_t iface;
-
-	/* Setting the serdes link mode is guesswork: there's no field in
-	 * the EEPROM which indicates what mode should be used.
-	 *
-	 * If the module wants 64b66b, then it must be >= 10G.
-	 *
-	 * If it's a gigabit-only fiber module, it probably does not have
-	 * a PHY, so switch to 802.3z negotiation mode. Otherwise, switch
-	 * to SGMII mode (which is required to support non-gigabit speeds).
-	 */
-	switch (id->base.encoding) {
-	case SFP_ENCODING_8472_64B66B:
-		iface = PHY_INTERFACE_MODE_10GKR;
-		break;
-
-	case SFP_ENCODING_8B10B:
-		if (!id->base.e1000_base_t &&
-		    !id->base.e100_base_lx &&
-		    !id->base.e100_base_fx)
-			iface = PHY_INTERFACE_MODE_1000BASEX;
-		else
-			iface = PHY_INTERFACE_MODE_SGMII;
-		break;
-
-	default:
-		if (id->base.e1000_base_cx) {
-			iface = PHY_INTERFACE_MODE_1000BASEX;
-			break;
-		}
-
-		iface = PHY_INTERFACE_MODE_NA;
-		dev_err(bus->sfp_dev,
-			"SFP module encoding does not support 8b10b nor 64b66b\n");
-		break;
-	}
-
-	return iface;
-}
-EXPORT_SYMBOL_GPL(sfp_parse_interface);
-
-/**
  * sfp_parse_support() - Parse the eeprom id for supported link modes
  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
  * @id: a pointer to the module's &struct sfp_eeprom_id
@@ -296,6 +234,45 @@ void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 }
 EXPORT_SYMBOL_GPL(sfp_parse_support);
 
+/**
+ * sfp_select_interface() - Select appropriate phy_interface_t mode
+ * @bus: a pointer to the &struct sfp_bus structure for the sfp module
+ * @id: a pointer to the module's &struct sfp_eeprom_id
+ * @link_modes: ethtool link modes mask
+ *
+ * Derive the phy_interface_t mode for the information found in the
+ * module's identifying EEPROM and the link modes mask. There is no
+ * standard or defined way to derive this information, so we decide
+ * based upon the link mode mask.
+ */
+phy_interface_t sfp_select_interface(struct sfp_bus *bus,
+				     const struct sfp_eeprom_id *id,
+				     unsigned long *link_modes)
+{
+	if (phylink_test(link_modes, 10000baseCR_Full) ||
+	    phylink_test(link_modes, 10000baseSR_Full) ||
+	    phylink_test(link_modes, 10000baseLR_Full) ||
+	    phylink_test(link_modes, 10000baseLRM_Full) ||
+	    phylink_test(link_modes, 10000baseER_Full))
+		return PHY_INTERFACE_MODE_10GKR;
+
+	if (phylink_test(link_modes, 2500baseX_Full))
+		return PHY_INTERFACE_MODE_2500BASEX;
+
+	if (id->base.e1000_base_t ||
+	    id->base.e100_base_lx ||
+	    id->base.e100_base_fx)
+		return PHY_INTERFACE_MODE_SGMII;
+
+	if (phylink_test(link_modes, 1000baseX_Full))
+		return PHY_INTERFACE_MODE_1000BASEX;
+
+	dev_warn(bus->sfp_dev, "Unable to ascertain link mode\n");
+
+	return PHY_INTERFACE_MODE_NA;
+}
+EXPORT_SYMBOL_GPL(sfp_select_interface);
+
 static LIST_HEAD(sfp_buses);
 static DEFINE_MUTEX(sfp_mutex);
 
diff --git a/include/linux/sfp.h b/include/linux/sfp.h
index e724d5a3dd80..ebce9e24906a 100644
--- a/include/linux/sfp.h
+++ b/include/linux/sfp.h
@@ -422,10 +422,11 @@ struct sfp_upstream_ops {
 #if IS_ENABLED(CONFIG_SFP)
 int sfp_parse_port(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 		   unsigned long *support);
-phy_interface_t sfp_parse_interface(struct sfp_bus *bus,
-				    const struct sfp_eeprom_id *id);
 void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 		       unsigned long *support);
+phy_interface_t sfp_select_interface(struct sfp_bus *bus,
+				     const struct sfp_eeprom_id *id,
+				     unsigned long *link_modes);
 
 int sfp_get_module_info(struct sfp_bus *bus, struct ethtool_modinfo *modinfo);
 int sfp_get_module_eeprom(struct sfp_bus *bus, struct ethtool_eeprom *ee,
@@ -444,18 +445,19 @@ static inline int sfp_parse_port(struct sfp_bus *bus,
 	return PORT_OTHER;
 }
 
-static inline phy_interface_t sfp_parse_interface(struct sfp_bus *bus,
-						const struct sfp_eeprom_id *id)
-{
-	return PHY_INTERFACE_MODE_NA;
-}
-
 static inline void sfp_parse_support(struct sfp_bus *bus,
 				     const struct sfp_eeprom_id *id,
 				     unsigned long *support)
 {
 }
 
+static inline phy_interface_t sfp_select_interface(struct sfp_bus *bus,
+						   const struct sfp_eeprom_id *id,
+						   unsigned long *link_modes)
+{
+	return PHY_INTERFACE_MODE_NA;
+}
+
 static inline int sfp_get_module_info(struct sfp_bus *bus,
 				      struct ethtool_modinfo *modinfo)
 {
-- 
2.7.4

[PATCH net-next 3/4] dt-bindings: add maximum power level to SFP binding

[Russell King]

Add the new maximum power level property to the SFP binding.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 Documentation/devicetree/bindings/net/sff,sfp.txt | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/sff,sfp.txt b/Documentation/devicetree/bindings/net/sff,sfp.txt
index f1c441bedf68..929591d52ed6 100644
--- a/Documentation/devicetree/bindings/net/sff,sfp.txt
+++ b/Documentation/devicetree/bindings/net/sff,sfp.txt
@@ -33,6 +33,10 @@ Transceiver
   Select (AKA RS1) output gpio signal (SFP+ only), low: low Tx rate, high:
   high Tx rate. Must not be present for SFF modules
 
+- maximum-power-milliwatt : Maximum module power consumption
+  Specifies the maximum power consumption allowable by a module in the
+  slot, in milli-Watts.  Presently, modules can be up to 1W, 1.5W or 2W.
+
 Example #1: Direct serdes to SFP connection
 
 sfp_eth3: sfp-eth3 {
@@ -40,6 +44,7 @@ sfp_eth3: sfp-eth3 {
 	i2c-bus = <&sfp_1g_i2c>;
 	los-gpios = <&cpm_gpio2 22 GPIO_ACTIVE_HIGH>;
 	mod-def0-gpios = <&cpm_gpio2 21 GPIO_ACTIVE_LOW>;
+	maximum-power-milliwatt = <1000>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&cpm_sfp_1g_pins &cps_sfp_1g_pins>;
 	tx-disable-gpios = <&cps_gpio1 24 GPIO_ACTIVE_HIGH>;
-- 
2.7.4

Re: [PATCH net-next 3/4] dt-bindings: add maximum power level to SFP binding

[Russell King - ARM Linux]

Hi Rob,

This patch, and the patches that make use of it have now been merged
into their respective trees, but I note that you haven't reviewed
this patch.  Obviously, providing an ack is now moot, but it would
still be good for a response before 4.16-final is released.

On Tue, Feb 27, 2018 at 03:53:07PM +0000, Russell King wrote:
> Add the new maximum power level property to the SFP binding.
> 
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
> ---
>  Documentation/devicetree/bindings/net/sff,sfp.txt | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/sff,sfp.txt b/Documentation/devicetree/bindings/net/sff,sfp.txt
> index f1c441bedf68..929591d52ed6 100644
> --- a/Documentation/devicetree/bindings/net/sff,sfp.txt
> +++ b/Documentation/devicetree/bindings/net/sff,sfp.txt
> @@ -33,6 +33,10 @@ Transceiver
>    Select (AKA RS1) output gpio signal (SFP+ only), low: low Tx rate, high:
>    high Tx rate. Must not be present for SFF modules
>  
> +- maximum-power-milliwatt : Maximum module power consumption
> +  Specifies the maximum power consumption allowable by a module in the
> +  slot, in milli-Watts.  Presently, modules can be up to 1W, 1.5W or 2W.
> +
>  Example #1: Direct serdes to SFP connection
>  
>  sfp_eth3: sfp-eth3 {
> @@ -40,6 +44,7 @@ sfp_eth3: sfp-eth3 {
>  	i2c-bus = <&sfp_1g_i2c>;
>  	los-gpios = <&cpm_gpio2 22 GPIO_ACTIVE_HIGH>;
>  	mod-def0-gpios = <&cpm_gpio2 21 GPIO_ACTIVE_LOW>;
> +	maximum-power-milliwatt = <1000>;
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&cpm_sfp_1g_pins &cps_sfp_1g_pins>;
>  	tx-disable-gpios = <&cps_gpio1 24 GPIO_ACTIVE_HIGH>;
> -- 
> 2.7.4
> 

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

[PATCH net-next 4/4] sfp: add high power module support

[Russell King]

From: Jon Nettleton <jon@solid-run.com>

This patch is the result of work by both Jon Nettleton and Russell King.
Jon wrote the original patch, adding support for SFP modules which
require a power level greater than '1'.

Russell's changes:
- Fix the power levels for big-endian, and make the code flow better.
- Convert to use device_property_read_u8()
- Warn for power levels exceeding host level
  SFF-8431 says:

  "To avoid exceeding system power supply limits and cooling capacity,
   all modules at power up by default shall operate with up to 1.0 W.
   Hosts supporting Power Level II or III operation may enable a Power
   Level II or III module through the 2-wire interface. Power Level II
   or III modules shall assert the power level declaration bit of
   SFF-8472."

  Print a warning for modules that exceed the host power level, and
  leave them operating in power level 1.

- Fix i2c write
  The first byte of any write after the bus address is always the
  device address.  In order to write a value to device D, address I,
  value V, we need to generate on the bus:

    S DDDDDDDD A IIIIIIII A VVVVVVVV A P

  where S = start, R = restart, A = ack, P = stop.  Splitting this
  as two:

    S DDDDDDDD A IIIIIIII A R DDDDDDDD A VVVVVVVV A P

  results in the device's address register being written first by I
  and then by V - the addressed register within the device is not
  written.

- Avoid power mode switching if 0xa2 is not implemented
  Some modules indicate that they support power level II or power level
  III, but do not implement address 0xa2, meaning that the bit to set
  them to high power mode is not accessible.

  These modules appear to have the sff8472_compliance field set to zero,
  and also do not implement diagnostics.  Detect this, but also ensure
  that the module does not require the address switching mode, which we
  do not implement.

- Use mW for power level rather than power level number.

- Fix high power mode transition
  We must not switch to SFP_MOD_PRESENT state until we have finished
  initialising, because the remaining state machines check for that
  state.  Add SFP_MOD_HPOWER as an intermediate state.

- Use definition for I2C register address rather than constant.

Signed-off-by: Jon Nettleton <jon@solid-run.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/sfp.c | 150 ++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 132 insertions(+), 18 deletions(-)

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 6c7d9289078d..83bf4959b043 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -42,6 +42,7 @@ enum {
 
 	SFP_MOD_EMPTY = 0,
 	SFP_MOD_PROBE,
+	SFP_MOD_HPOWER,
 	SFP_MOD_PRESENT,
 	SFP_MOD_ERROR,
 
@@ -86,6 +87,7 @@ static const enum gpiod_flags gpio_flags[] = {
  * access the I2C EEPROM.  However, Avago modules require 300ms.
  */
 #define T_PROBE_INIT	msecs_to_jiffies(300)
+#define T_HPOWER_LEVEL	msecs_to_jiffies(300)
 #define T_PROBE_RETRY	msecs_to_jiffies(100)
 
 /* SFP modules appear to always have their PHY configured for bus address
@@ -110,10 +112,12 @@ struct sfp {
 	struct sfp_bus *sfp_bus;
 	struct phy_device *mod_phy;
 	const struct sff_data *type;
+	u32 max_power_mW;
 
 	unsigned int (*get_state)(struct sfp *);
 	void (*set_state)(struct sfp *, unsigned int);
 	int (*read)(struct sfp *, bool, u8, void *, size_t);
+	int (*write)(struct sfp *, bool, u8, void *, size_t);
 
 	struct gpio_desc *gpio[GPIO_MAX];
 
@@ -201,10 +205,11 @@ static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
 	}
 }
 
-static int sfp__i2c_read(struct i2c_adapter *i2c, u8 bus_addr, u8 dev_addr,
-			 void *buf, size_t len)
+static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
+			size_t len)
 {
 	struct i2c_msg msgs[2];
+	u8 bus_addr = a2 ? 0x51 : 0x50;
 	int ret;
 
 	msgs[0].addr = bus_addr;
@@ -216,17 +221,38 @@ static int sfp__i2c_read(struct i2c_adapter *i2c, u8 bus_addr, u8 dev_addr,
 	msgs[1].len = len;
 	msgs[1].buf = buf;
 
-	ret = i2c_transfer(i2c, msgs, ARRAY_SIZE(msgs));
+	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
 	if (ret < 0)
 		return ret;
 
 	return ret == ARRAY_SIZE(msgs) ? len : 0;
 }
 
-static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 addr, void *buf,
-			size_t len)
+static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
+	size_t len)
 {
-	return sfp__i2c_read(sfp->i2c, a2 ? 0x51 : 0x50, addr, buf, len);
+	struct i2c_msg msgs[1];
+	u8 bus_addr = a2 ? 0x51 : 0x50;
+	int ret;
+
+	msgs[0].addr = bus_addr;
+	msgs[0].flags = 0;
+	msgs[0].len = 1 + len;
+	msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
+	if (!msgs[0].buf)
+		return -ENOMEM;
+
+	msgs[0].buf[0] = dev_addr;
+	memcpy(&msgs[0].buf[1], buf, len);
+
+	ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
+
+	kfree(msgs[0].buf);
+
+	if (ret < 0)
+		return ret;
+
+	return ret == ARRAY_SIZE(msgs) ? len : 0;
 }
 
 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
@@ -239,6 +265,7 @@ static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
 
 	sfp->i2c = i2c;
 	sfp->read = sfp_i2c_read;
+	sfp->write = sfp_i2c_write;
 
 	i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
 	if (IS_ERR(i2c_mii))
@@ -274,6 +301,11 @@ static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
 	return sfp->read(sfp, a2, addr, buf, len);
 }
 
+static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
+{
+	return sfp->write(sfp, a2, addr, buf, len);
+}
+
 static unsigned int sfp_check(void *buf, size_t len)
 {
 	u8 *p, check;
@@ -462,21 +494,83 @@ static void sfp_sm_mod_init(struct sfp *sfp)
 		sfp_sm_probe_phy(sfp);
 }
 
+static int sfp_sm_mod_hpower(struct sfp *sfp)
+{
+	u32 power;
+	u8 val;
+	int err;
+
+	power = 1000;
+	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
+		power = 1500;
+	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
+		power = 2000;
+
+	if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE &&
+	    (sfp->id.ext.diagmon & (SFP_DIAGMON_DDM | SFP_DIAGMON_ADDRMODE)) !=
+	    SFP_DIAGMON_DDM) {
+		/* The module appears not to implement bus address 0xa2,
+		 * or requires an address change sequence, so assume that
+		 * the module powers up in the indicated power mode.
+		 */
+		if (power > sfp->max_power_mW) {
+			dev_err(sfp->dev,
+				"Host does not support %u.%uW modules\n",
+				power / 1000, (power / 100) % 10);
+			return -EINVAL;
+		}
+		return 0;
+	}
+
+	if (power > sfp->max_power_mW) {
+		dev_warn(sfp->dev,
+			 "Host does not support %u.%uW modules, module left in power mode 1\n",
+			 power / 1000, (power / 100) % 10);
+		return 0;
+	}
+
+	if (power <= 1000)
+		return 0;
+
+	err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
+	if (err != sizeof(val)) {
+		dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
+		err = -EAGAIN;
+		goto err;
+	}
+
+	val |= BIT(0);
+
+	err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
+	if (err != sizeof(val)) {
+		dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
+		err = -EAGAIN;
+		goto err;
+	}
+
+	dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
+		 power / 1000, (power / 100) % 10);
+	return T_HPOWER_LEVEL;
+
+err:
+	return err;
+}
+
 static int sfp_sm_mod_probe(struct sfp *sfp)
 {
 	/* SFP module inserted - read I2C data */
 	struct sfp_eeprom_id id;
 	u8 check;
-	int err;
+	int ret;
 
-	err = sfp_read(sfp, false, 0, &id, sizeof(id));
-	if (err < 0) {
-		dev_err(sfp->dev, "failed to read EEPROM: %d\n", err);
+	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
+	if (ret < 0) {
+		dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
 		return -EAGAIN;
 	}
 
-	if (err != sizeof(id)) {
-		dev_err(sfp->dev, "EEPROM short read: %d\n", err);
+	if (ret != sizeof(id)) {
+		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
 		return -EAGAIN;
 	}
 
@@ -521,7 +615,11 @@ static int sfp_sm_mod_probe(struct sfp *sfp)
 		dev_warn(sfp->dev,
 			 "module address swap to access page 0xA2 is not supported.\n");
 
-	return sfp_module_insert(sfp->sfp_bus, &sfp->id);
+	ret = sfp_module_insert(sfp->sfp_bus, &sfp->id);
+	if (ret < 0)
+		return ret;
+
+	return sfp_sm_mod_hpower(sfp);
 }
 
 static void sfp_sm_mod_remove(struct sfp *sfp)
@@ -560,17 +658,25 @@ static void sfp_sm_event(struct sfp *sfp, unsigned int event)
 		if (event == SFP_E_REMOVE) {
 			sfp_sm_ins_next(sfp, SFP_MOD_EMPTY, 0);
 		} else if (event == SFP_E_TIMEOUT) {
-			int err = sfp_sm_mod_probe(sfp);
+			int val = sfp_sm_mod_probe(sfp);
 
-			if (err == 0)
+			if (val == 0)
 				sfp_sm_ins_next(sfp, SFP_MOD_PRESENT, 0);
-			else if (err == -EAGAIN)
-				sfp_sm_set_timer(sfp, T_PROBE_RETRY);
-			else
+			else if (val > 0)
+				sfp_sm_ins_next(sfp, SFP_MOD_HPOWER, val);
+			else if (val != -EAGAIN)
 				sfp_sm_ins_next(sfp, SFP_MOD_ERROR, 0);
+			else
+				sfp_sm_set_timer(sfp, T_PROBE_RETRY);
 		}
 		break;
 
+	case SFP_MOD_HPOWER:
+		if (event == SFP_E_TIMEOUT) {
+			sfp_sm_ins_next(sfp, SFP_MOD_PRESENT, 0);
+			break;
+		}
+		/* fallthrough */
 	case SFP_MOD_PRESENT:
 	case SFP_MOD_ERROR:
 		if (event == SFP_E_REMOVE) {
@@ -889,6 +995,14 @@ static int sfp_probe(struct platform_device *pdev)
 	if (!(sfp->gpio[GPIO_MODDEF0]))
 		sfp->get_state = sff_gpio_get_state;
 
+	device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
+				 &sfp->max_power_mW);
+	if (!sfp->max_power_mW)
+		sfp->max_power_mW = 1000;
+
+	dev_info(sfp->dev, "Host maximum power %u.%uW\n",
+		 sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
+
 	sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
 	if (!sfp->sfp_bus)
 		return -ENOMEM;
-- 
2.7.4

Re: [PATCH net-next 0/4] SFP updates

[David Miller]

From: Russell King - ARM Linux <linux@armlinux.org.uk>
Date: Tue, 27 Feb 2018 15:52:18 +0000

> Included in this series are a further few updates for SFP support:
> 
> - Adding support for Fiberstore's non-standard BiDi modules operating
>   at 1310nm/1550nm wavelengths rather than the 1000BASE-BX standard of
>   1310nm/1490nm.
> - Adding support for negotiating the PHY interface mode with the MAC,
>   so that modules supporting faster speeds and Gigabit ethernet work
>   with Gigabit-only MACs.
> - Adding support for high power (>1W) SFP modules.

Series applied, thanks Russell.