From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Wed, 20 Nov 2019 11:42:42 +0000
Subject: net: sfp: add support for module quirks
Patch-mainline: v5.5-rc1
Git-commit: b34bb2cb5b62c7397c28fcc335e8047a687eada4
References: bsc#1154353

Add support for applying module quirks to the list of supported
ethtool link modes.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/phy/sfp-bus.c |   54 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -10,6 +10,12 @@
 
 #include "sfp.h"
 
+struct sfp_quirk {
+	const char *vendor;
+	const char *part;
+	void (*modes)(const struct sfp_eeprom_id *id, unsigned long *modes);
+};
+
 /**
  * struct sfp_bus - internal representation of a sfp bus
  */
@@ -22,6 +28,7 @@ struct sfp_bus {
 	const struct sfp_socket_ops *socket_ops;
 	struct device *sfp_dev;
 	struct sfp *sfp;
+	const struct sfp_quirk *sfp_quirk;
 
 	const struct sfp_upstream_ops *upstream_ops;
 	void *upstream;
@@ -31,6 +38,46 @@ struct sfp_bus {
 	bool started;
 };
 
+static const struct sfp_quirk sfp_quirks[] = {
+};
+
+static size_t sfp_strlen(const char *str, size_t maxlen)
+{
+	size_t size, i;
+
+	/* Trailing characters should be filled with space chars */
+	for (i = 0, size = 0; i < maxlen; i++)
+		if (str[i] != ' ')
+			size = i + 1;
+
+	return size;
+}
+
+static bool sfp_match(const char *qs, const char *str, size_t len)
+{
+	if (!qs)
+		return true;
+	if (strlen(qs) != len)
+		return false;
+	return !strncmp(qs, str, len);
+}
+
+static const struct sfp_quirk *sfp_lookup_quirk(const struct sfp_eeprom_id *id)
+{
+	const struct sfp_quirk *q;
+	unsigned int i;
+	size_t vs, ps;
+
+	vs = sfp_strlen(id->base.vendor_name, ARRAY_SIZE(id->base.vendor_name));
+	ps = sfp_strlen(id->base.vendor_pn, ARRAY_SIZE(id->base.vendor_pn));
+
+	for (i = 0, q = sfp_quirks; i < ARRAY_SIZE(sfp_quirks); i++, q++)
+		if (sfp_match(q->vendor, id->base.vendor_name, vs) &&
+		    sfp_match(q->part, id->base.vendor_pn, ps))
+			return q;
+
+	return NULL;
+}
 /**
  * sfp_parse_port() - Parse the EEPROM base ID, setting the port type
  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
@@ -234,6 +281,9 @@ void sfp_parse_support(struct sfp_bus *b
 			phylink_set(modes, 1000baseX_Full);
 	}
 
+	if (bus->sfp_quirk)
+		bus->sfp_quirk->modes(id, modes);
+
 	bitmap_or(support, support, modes, __ETHTOOL_LINK_MODE_MASK_NBITS);
 
 	phylink_set(support, Autoneg);
@@ -610,6 +660,8 @@ int sfp_module_insert(struct sfp_bus *bu
 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 	int ret = 0;
 
+	bus->sfp_quirk = sfp_lookup_quirk(id);
+
 	if (ops && ops->module_insert)
 		ret = ops->module_insert(bus->upstream, id);
 
@@ -623,6 +675,8 @@ void sfp_module_remove(struct sfp_bus *b
 
 	if (ops && ops->module_remove)
 		ops->module_remove(bus->upstream);
+
+	bus->sfp_quirk = NULL;
 }
 EXPORT_SYMBOL_GPL(sfp_module_remove);