From f75eb7871319d7e81f38615ff494d64630cac2e2 Mon Sep 17 00:00:00 2001
From: Antoine Tenart <antoine.tenart@bootlin.com>
Date: Tue, 22 May 2018 12:17:59 +0200
Subject: [PATCH] net: phy: sfp: warn the user when no tx_disable pin is
available
Git-commit: a1f5d1f0dfccea54e1d9c2da16fd8c9b54f81a75
Patch-mainline: v4.18-rc1
References: git-fixes
In case no Tx disable pin is available the SFP modules will always be
emitting. This could be an issue when using modules using laser as their
light source as we would have no way to disable it when the fiber is
removed. This patch adds a warning when registering an SFP cage which do
not have its tx_disable pin wired or available.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
drivers/net/phy/sfp.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index b025b7d2c865..7f54ff15aec4 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -869,6 +869,15 @@ static int sfp_probe(struct platform_device *pdev)
if (poll)
mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
+ /* We could have an issue in cases no Tx disable pin is available or
+ * wired as modules using a laser as their light source will continue to
+ * be active when the fiber is removed. This could be a safety issue and
+ * we should at least warn the user about that.
+ */
+ if (!sfp->gpio[GPIO_TX_DISABLE])
+ dev_warn(sfp->dev,
+ "No tx_disable pin: SFP modules will always be emitting.\n");
+
return 0;
}
--
2.16.4