net: usb: sr9700: only store little-endian values in __le16 variable

In sr_mdio_read() the local variable res is used to store both
little-endian and host byte order values. This prevents Sparse
from helping us by flagging when endian miss matches occur - the
detection process hinges on the type of variables matching the
byte order of values stored in them.

Address this by adding a new local variable, word, to store little-endian
values; change the type of res to int, and use it to store host-byte
order values.

Flagged by Sparse as:

.../sr9700.c:205:21: warning: incorrect type in assignment (different base types)
.../sr9700.c:205:21:    expected restricted __le16 [addressable] [usertype] res
.../sr9700.c:205:21:    got int
.../sr9700.c:207:21: warning: incorrect type in assignment (different base types)
.../sr9700.c:207:21:    expected restricted __le16 [addressable] [usertype] res
.../sr9700.c:207:21:    got int
.../sr9700.c:212:16: warning: incorrect type in return expression (different base types)
.../sr9700.c:212:16:    expected int
.../sr9700.c:212:16:    got restricted __le16 [addressable] [usertype] res

Compile tested only.
No functional change intended.

Signed-off-by: Simon Horman <horms@kernel.org>
Message-ID: <20241016-blackbird-le16-v1-1-97ba8de6b38f@kernel.org>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>

diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c
index cb7d2f798fb43622c7e954aeebeab8edede4cb49..091bc2aca7e8e70bff45b2329c7409246d5f020b 100644 (file)
--- a/drivers/net/usb/sr9700.c
+++ b/drivers/net/usb/sr9700.c
@@ -177,9 +177,9 @@ static int sr9700_get_eeprom(struct net_device *netdev,
 static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc)
 {
        struct usbnet *dev = netdev_priv(netdev);
-       __le16 res;
+       int err, res;
+       __le16 word;
        int rc = 0;
-       int err;
 
        if (phy_id) {
                netdev_dbg(netdev, "Only internal phy supported\n");
@@ -197,14 +197,14 @@ static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc)
                if (value & NSR_LINKST)
                        rc = 1;
        }
-       err = sr_share_read_word(dev, 1, loc, &res);
+       err = sr_share_read_word(dev, 1, loc, &word);
        if (err < 0)
                return err;
 
        if (rc == 1)
-               res = le16_to_cpu(res) | BMSR_LSTATUS;
+               res = le16_to_cpu(word) | BMSR_LSTATUS;
        else
-               res = le16_to_cpu(res) & ~BMSR_LSTATUS;
+               res = le16_to_cpu(word) & ~BMSR_LSTATUS;
 
        netdev_dbg(netdev, "sr_mdio_read() phy_id=0x%02x, loc=0x%02x, returns=0x%04x\n",
                   phy_id, loc, res);