Add support for VSOL V2801F/CarlitoxxPro CPGOS03 GPON module

Add a workaround for the detection of VSOL V2801F / CarlitoxxPro CPGOS03-0490 v2.0 GPON module which CarlitoxxPro states needs single byte I2C reads to the EEPROM.

Pali Rohár reports that he also has a CarlitoxxPro-based V2801F module, which reports a manufacturer of "OEM". This manufacturer can't be matched as it appears in many different modules, so also match the part number too.

Reported-by Thomas Schreiber <[email protected]>

Reported-by Pali Rohár <[email protected]>

Tested-by Pali Rohár <[email protected]>

Signed-off-by Russell King <[email protected]>

---
 drivers/net/phy/sfp.c | 63 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 58 insertions(+), 5 deletions(-)

drivers/net/phy/sfp.c +58 -5

index 34aa196b7465..0b26495973ff 100644
@@ -219,6 +219,7 @@ struct sfp {
 	struct sfp_bus *sfp_bus;
 	struct phy_device *mod_phy;
 	const struct sff_data *type;
+	size_t i2c_block_size;
 	u32 max_power_mW;
 
 	unsigned int (*get_state)(struct sfp *);

@@ -335,10 +336,19 @@ 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;
+	size_t block_size;
 	size_t this_len;
+	u8 bus_addr;
 	int ret;
 
+	if (a2) {
+		block_size = 16;
+		bus_addr = 0x51;
+	} else {
+		block_size = sfp->i2c_block_size;
+		bus_addr = 0x50;
+	}
+
 	msgs[0].addr = bus_addr;
 	msgs[0].flags = 0;
 	msgs[0].len = 1;

@@ -350,8 +360,8 @@ static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
 
 	while (len) {
 		this_len = len;
-		if (this_len > 16)
-			this_len = 16;
+		if (this_len > block_size)
+			this_len = block_size;
 
 		msgs[1].len = this_len;
 

@@ -1632,6 +1642,28 @@ static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
 	return 0;
 }
 
+/* Some modules (Nokia 3FE46541AA) lock up if byte 0x51 is read as a
+ * single read. Switch back to reading 16 byte blocks unless we have
+ * a CarlitoxxPro module (rebranded VSOL V2801F). Even more annoyingly,
+ * some VSOL V2801F have the vendor name changed to OEM.
+ */
+static int sfp_quirk_i2c_block_size(const sfp_eeprom_base *base)
+{
+	if (!memcmp(base->vendor_name, "VSOL            ", 16))
+		return 1;
+	if (!memcmp(base->vendor_name, "OEM             ", 16) &&
+	    !memcmp(base->vendor_pn,   "V2801F          ", 16))
+		return 1;
+
+	/* Some modules can't cope with long reads */
+	return 16;
+}
+
+static void sfp_quirks_base(struct sfp *sfp, const sfp_eeprom_base *base)
+{
+	sfp->i2c_block_size = sfp_quirk_i2c_block_size(base);
+}
+
 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
 {
 	u8 check;

@@ -1673,14 +1705,20 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
 	u8 check;
 	int ret;
 
-	ret = sfp_read(sfp, false, 0, &id, sizeof(id));
+	/* Some modules (CarlitoxxPro CPGOS03-0490) do not support multibyte
+	 * reads from the EEPROM, so start by reading the base identifying
+	 * information one byte at a time.
+	 */
+	sfp->i2c_block_size = 1;
+
+	ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
 	if (ret < 0) {
 		if (report)
 			dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
 		return -EAGAIN;
 	}
 
-	if (ret != sizeof(id)) {
+	if (ret != sizeof(id.base)) {
 		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
 		return -EAGAIN;
 	}

@@ -1719,6 +1757,21 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
 		}
 	}
 
+	/* Apply any early module-specific quirks */
+	sfp_quirks_base(sfp, &id.base);
+
+	ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
+	if (ret < 0) {
+		if (report)
+			dev_err(sfp->dev, "failed to read EEPROM: %d\n", ret);
+		return -EAGAIN;
+	}
+
+	if (ret != sizeof(id.ext)) {
+		dev_err(sfp->dev, "EEPROM short read: %d\n", ret);
+		return -EAGAIN;
+	}
+
 	check = sfp_check(&id.ext, sizeof(id.ext) - 1);
 	if (check != id.ext.cc_ext) {
 		if (cotsworks) {

Signature · 1 line

2.20.1

+/* Some modules (Nokia 3FE46541AA) lock up if byte 0x51 is read as a
+ * single read. Switch back to reading 16 byte blocks unless we have
+ * a CarlitoxxPro module (rebranded VSOL V2801F). Even more annoyingly,
+ * some VSOL V2801F have the vendor name changed to OEM.

Quoted 4 lines

+/* Some modules (Nokia 3FE46541AA) lock up if byte 0x51 is read as a
+ * single read. Switch back to reading 16 byte blocks unless we have
+ * a CarlitoxxPro module (rebranded VSOL V2801F). Even more annoyingly,
+ * some VSOL V2801F have the vendor name changed to OEM.

Hi Russell

I guess it is more likely, the vendor name has not been changed _from_ OEM.

Do not check the encoding when deriving 1000BASE-X from the bitrate when no other modes are discovered. Some GPON modules (VSOL V2801F and CarlitoxxPro CPGOS03-0490 v2.0) indicate NRZ encoding with a 1200Mbaud bitrate, but should be driven with 1000BASE-X on the host side.

Quoted 5 lines · Russell King

Do not check the encoding when deriving 1000BASE-X from the bitrate when no other modes are discovered. Some GPON modules (VSOL V2801F and CarlitoxxPro CPGOS03-0490 v2.0) indicate NRZ encoding with a 1200Mbaud bitrate, but should be driven with 1000BASE-X on the host side.

Seems like somebody could make a nice side line writing SFP EEPROM validation tools. There obviously are none in widespread use!

Hi,

This patch set adds support for the V2801F / CarlitoxxPro module. This requires two changes:

1) the module only supports single byte reads to the ID EEPROM, while we need to still permit sequential reads to the diagnostics EEPROM for atomicity reasons.

2) we need to relax the encoding check when we have no reported capabilities to allow 1000base-X based on the module bitrate.

Thanks to Pali Rohár for responsive testing over the last two days.

 drivers/net/phy/sfp-bus.c | 11 ++++-----
 drivers/net/phy/sfp.c     | 63 +++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 63 insertions(+), 11 deletions(-)

Signature · 2 lines

RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

Jakub,

What's happening with these patches?

If I'm getting the patchwork URLs correct, these patches seem not to appear in patchwork. They both went to netdev as normal and where accepted by vger from what I can see.

Thanks.

Quoted 22 lines · Russell King - ARM Linux admin

Hi,

This patch set adds support for the V2801F / CarlitoxxPro module. This requires two changes:

1) the module only supports single byte reads to the ID EEPROM, while we need to still permit sequential reads to the diagnostics EEPROM for atomicity reasons.

2) we need to relax the encoding check when we have no reported capabilities to allow 1000base-X based on the module bitrate.

Thanks to Pali Rohár for responsive testing over the last two days.

 drivers/net/phy/sfp-bus.c | 11 ++++-----
 drivers/net/phy/sfp.c     | 63 +++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 63 insertions(+), 11 deletions(-)

Signature · 2 lines

RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

Signature · 2 lines

RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!