[PATCH 4.19 044/133] net: sfp: add support for module quirks

[Greg Kroah-Hartman]

From: Russell King <rmk+ker...@armlinux.org.uk>

[ Upstream commit b34bb2cb5b62c7397c28fcc335e8047a687eada4 ]

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

Signed-off-by: Russell King <rmk+ker...@armlinux.org.uk>
Reviewed-by: Andrew Lunn <and...@lunn.ch>
Reviewed-by: Florian Fainelli <f.faine...@gmail.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/net/phy/sfp-bus.c | 54 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index fef701bfad62e..bd3ea01bff0b8 100644
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -8,6 +8,12 @@
 
 #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
  */
@@ -20,6 +26,7 @@ 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;
@@ -30,6 +37,46 @@ 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
@@ -233,6 +280,9 @@ void sfp_parse_support(struct sfp_bus *bus, const struct 
sfp_eeprom_id *id,
                        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);
@@ -556,6 +606,8 @@ int sfp_module_insert(struct sfp_bus *bus, const struct 
sfp_eeprom_id *id)
        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);
 
@@ -569,6 +621,8 @@ void sfp_module_remove(struct sfp_bus *bus)
 
        if (ops && ops->module_remove)
                ops->module_remove(bus->upstream);
+
+       bus->sfp_quirk = NULL;
 }
 EXPORT_SYMBOL_GPL(sfp_module_remove);
 
-- 
2.25.1