Merge branch 'net-sfp-small-improvements'

Antoine Tenart says:

====================
net: sfp: small improvements

A small series of patches improving the SFP support by adding a warning
when no Tx disable pin is available, and making the i2c-bus property
mandatory.

Thanks!
Antoine

Since v1:
  - Removed the patch fixing the sfp driver when no i2c bus was described.
  - Made two new patches to make the i2c-bus property mandatory for sfp modules.

Since the phylink series:
  - s/-EOPNOTSUPP/-ENODEV/ in patch 1/2.
  - I added the acked-by tag in patch 2/2.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/sff,sfp.txt

@@ -7,11 +7,11 @@ Required properties:
   "sff,sfp" for SFP modules
   "sff,sff" for soldered down SFF modules
 
-Optional Properties:
-
 - i2c-bus : phandle of an I2C bus controller for the SFP two wire serial
   interface
 
+Optional Properties:
+
 - mod-def0-gpios : GPIO phandle and a specifier of the MOD-DEF0 (AKA Mod_ABS)
   module presence input gpio signal, active (module absent) high. Must
   not be present for SFF modules

drivers/net/phy/sfp.c

@@ -976,6 +976,7 @@ static int sfp_probe(struct platform_device *pdev)
 	if (pdev->dev.of_node) {
 		struct device_node *node = pdev->dev.of_node;
 		const struct of_device_id *id;
+		struct i2c_adapter *i2c;
 		struct device_node *np;
 
 		id = of_match_node(sfp_of_match, node);
@@ -985,19 +986,20 @@ static int sfp_probe(struct platform_device *pdev)
 		sff = sfp->type = id->data;
 
 		np = of_parse_phandle(node, "i2c-bus", 0);
-		if (np) {
-			struct i2c_adapter *i2c;
-
-			i2c = of_find_i2c_adapter_by_node(np);
-			of_node_put(np);
-			if (!i2c)
-				return -EPROBE_DEFER;
-
-			err = sfp_i2c_configure(sfp, i2c);
-			if (err < 0) {
-				i2c_put_adapter(i2c);
-				return err;
-			}
+		if (!np) {
+			dev_err(sfp->dev, "missing 'i2c-bus' property\n");
+			return -ENODEV;
+		}
+
+		i2c = of_find_i2c_adapter_by_node(np);
+		of_node_put(np);
+		if (!i2c)
+			return -EPROBE_DEFER;
+
+		err = sfp_i2c_configure(sfp, i2c);
+		if (err < 0) {
+			i2c_put_adapter(i2c);
+			return err;
 		}
 	}
 
@@ -1065,6 +1067,15 @@ 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;
 }