ipmi_ssif: fix unexpected driver unregister warning

If platform_driver_register() fails from init_ipmi_ssif(),
platform_driver_unregister() called unconditionally will
trigger following warning,

ipmi_ssif: Unable to register driver: -12
------------[ cut here ]------------
Unexpected driver unregister!
WARNING: CPU: 1 PID: 6305 at drivers/base/driver.c:193 driver_unregister+0x60/0x70 drivers/base/driver.c:193

Fix it by adding platform_registered variable, only unregister platform
driver when it is already successfully registered.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Message-Id: <20190524143724.43218-1-wangkefeng.wang@huawei.com>

Signed-off-by: Corey Minyard <cminyard@mvista.com>

diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index cf8156d..305fa50 100644 (file)
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -303,6 +303,7 @@ struct ssif_info {
        ((unsigned int) atomic_read(&(ssif)->stats[SSIF_STAT_ ## stat]))
 
 static bool initialized;
+static bool platform_registered;
 
 static void return_hosed_msg(struct ssif_info *ssif_info,
                             struct ipmi_smi_msg *msg);
@@ -2088,6 +2089,8 @@ static int init_ipmi_ssif(void)
                rv = platform_driver_register(&ipmi_driver);
                if (rv)
                        pr_err("Unable to register driver: %d\n", rv);
+               else
+                       platform_registered = true;
        }
 
        ssif_i2c_driver.address_list = ssif_address_list();
@@ -2111,7 +2114,7 @@ static void cleanup_ipmi_ssif(void)
 
        kfree(ssif_i2c_driver.address_list);
 
-       if (ssif_trydmi)
+       if (ssif_trydmi && platform_registered)
                platform_driver_unregister(&ipmi_driver);
 
        free_ssif_clients();