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Subject[PATCH] wl3501_cs: avoid bogus gcc-6 warning
Date
gcc-6 on x86 started warning about wl3501_get_encode when building
with -O2:

drivers/net/wireless/wl3501_cs.c: In function ‘wl3501_get_encode’:
drivers/net/wireless/wl3501_cs.c:1769:5: warning: ‘implemented’ may be used uninitialized in this function
drivers/net/wireless/wl3501_cs.c:1686:19: warning: ‘threshold’ may be used uninitialized in this function
drivers/net/wireless/wl3501_cs.c:1702:20: warning: ‘threshold’ may be used uninitialized in this function
drivers/net/wireless/wl3501_cs.c:1719:23: warning: ‘txpow’ may be used uninitialized in this function
drivers/net/wireless/wl3501_cs.c:1752:20: warning: ‘retry’ may be used uninitialized in this function
drivers/net/wireless/wl3501_cs.c:1806:25: warning: ‘pwr_state’ may be used uninitialized in this function
drivers/net/wireless/wl3501_cs.c:1383:24: warning: ‘value’ may be used uninitialized in this function

I could not figure out what exactly confuses gcc here, but splitting the
wl3501_get_mib_value function into two helps the compiler to figure out
that the variables are not actually used uninitialized, and makes it
slightly clearer to a human reader what the function actually does and
which parts of it are under the spinlock.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/drivers/net/wireless/wl3501_cs.c b/drivers/net/wireless/wl3501_cs.c
index 13fd734b61ec..82d94f83b6b4 100644
--- a/drivers/net/wireless/wl3501_cs.c
+++ b/drivers/net/wireless/wl3501_cs.c
@@ -378,8 +378,7 @@ static int wl3501_esbq_exec(struct wl3501_card *this, void *sig, int sig_size)
return rc;
}

-static int wl3501_get_mib_value(struct wl3501_card *this, u8 index,
- void *bf, int size)
+static int wl3501_request_mib(struct wl3501_card *this, u8 index, void *bf)
{
struct wl3501_get_req sig = {
.sig_id = WL3501_SIG_GET_REQ,
@@ -395,20 +394,32 @@ static int wl3501_get_mib_value(struct wl3501_card *this, u8 index,
wl3501_set_to_wla(this, ptr, &sig, sizeof(sig));
wl3501_esbq_req(this, &ptr);
this->sig_get_confirm.mib_status = 255;
- spin_unlock_irqrestore(&this->lock, flags);
- rc = wait_event_interruptible(this->wait,
- this->sig_get_confirm.mib_status != 255);
- if (!rc)
- memcpy(bf, this->sig_get_confirm.mib_value,
- size);
- goto out;
+ rc = 0;
}
}
spin_unlock_irqrestore(&this->lock, flags);
-out:
+
return rc;
}

+static int wl3501_get_mib_value(struct wl3501_card *this, u8 index,
+ void *bf, int size)
+{
+ int rc;
+
+ rc = wl3501_request_mib(this, index, bf);
+ if (rc)
+ return rc;
+
+ rc = wait_event_interruptible(this->wait,
+ this->sig_get_confirm.mib_status != 255);
+ if (rc)
+ return rc;
+
+ memcpy(bf, this->sig_get_confirm.mib_value, size);
+ return 0;
+}
+
static int wl3501_pwr_mgmt(struct wl3501_card *this, int suspend)
{
struct wl3501_pwr_mgmt_req sig = {
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