On Wed, Dec 30, 2020 at 05:57:58PM +0100, Pali Rohár wrote:

On Wednesday 30 December 2020 16:13:10 Russell King - ARM Linux admin wrote:

quoted

On Wed, Dec 30, 2020 at 04:47:54PM +0100, Pali Rohár wrote:

quoted

Some GPON SFP modules (e.g. Ubiquiti U-Fiber Instant) have set both
SFP_OPTIONS_LOS_INVERTED and SFP_OPTIONS_LOS_NORMAL bits in their EEPROM.

Such combination of bits is meaningless so assume that LOS signal is not
implemented.

This patch fixes link carrier for GPON SFP module Ubiquiti U-Fiber Instant.

Co-developed-by: Russell King <redacted>
Signed-off-by: Russell King <redacted>

No, this is not co-developed. The patch content is exactly what _I_
sent you, only the commit description is your own.

Sorry, in this case I misunderstood usage of this Co-developed-by tag.
I will remove it in next iteration of patches.

You need to mark me as the author of the code at the very least...

quoted

quoted

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 drivers/net/phy/sfp.c | 36 ++++++++++++++++++++++--------------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 73f3ecf15260..d47485ed239c 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c

@@ -1475,15 +1475,19 @@ static void sfp_sm_link_down(struct sfp *sfp)
 
 static void sfp_sm_link_check_los(struct sfp *sfp)
 {
-	unsigned int los = sfp->state & SFP_F_LOS;
+	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
+	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
+	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
+	bool los = false;
 
 	/* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
-	 * are set, we assume that no LOS signal is available.
+	 * are set, we assume that no LOS signal is available. If both are
+	 * set, we assume LOS is not implemented (and is meaningless.)
 	 */
-	if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED))
-		los ^= SFP_F_LOS;
-	else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL)))
-		los = 0;
+	if (los_options == los_inverted)
+		los = !(sfp->state & SFP_F_LOS);
+	else if (los_options == los_normal)
+		los = !!(sfp->state & SFP_F_LOS);
 
 	if (los)
 		sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);

@@ -1493,18 +1497,22 @@ static void sfp_sm_link_check_los(struct sfp *sfp)
 
 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
 {
-	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
-		event == SFP_E_LOS_LOW) ||
-	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
-		event == SFP_E_LOS_HIGH);
+	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
+	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
+	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
+
+	return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
+	       (los_options == los_normal && event == SFP_E_LOS_HIGH);
 }
 
 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
 {
-	return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) &&
-		event == SFP_E_LOS_HIGH) ||
-	       (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) &&
-		event == SFP_E_LOS_LOW);
+	const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
+	const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
+	__be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
+
+	return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
+	       (los_options == los_normal && event == SFP_E_LOS_LOW);
 }
 
 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)

-- 
2.20.1

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-- 
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FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!