MIPS: Lantiq: Fix check for return value of request_mem_region()

request_mem_region() returns a pointer and not an integer with an error
value. A check for "< 0" on a pointer will cause problems, replace it
with not null checks instead. This was found with sparse.

Signed-off-by: Hauke Mehrtens <hauke.mehrtens@lantiq.com>
Acked-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11395/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/lantiq/irq.c

@@ -369,8 +369,8 @@ int __init icu_of_init(struct device_node *node, struct device_node *parent)
 		if (of_address_to_resource(node, i, &res))
 			panic("Failed to get icu memory range");
 
-		if (request_mem_region(res.start, resource_size(&res),
-					res.name) < 0)
+		if (!request_mem_region(res.start, resource_size(&res),
+					res.name))
 			pr_err("Failed to request icu memory");
 
 		ltq_icu_membase[i] = ioremap_nocache(res.start,
@@ -449,8 +449,8 @@ int __init icu_of_init(struct device_node *node, struct device_node *parent)
 		if (ret != exin_avail)
 			panic("failed to load external irq resources");
 
-		if (request_mem_region(res.start, resource_size(&res),
-							res.name) < 0)
+		if (!request_mem_region(res.start, resource_size(&res),
+							res.name))
 			pr_err("Failed to request eiu memory");
 
 		ltq_eiu_membase = ioremap_nocache(res.start,

arch/mips/lantiq/xway/reset.c

@@ -288,7 +288,7 @@ static int __init mips_reboot_setup(void)
 	if (of_address_to_resource(ltq_rcu_np, 0, &res))
 		panic("Failed to get rcu memory range");
 
-	if (request_mem_region(res.start, resource_size(&res), res.name) < 0)
+	if (!request_mem_region(res.start, resource_size(&res), res.name))
 		pr_err("Failed to request rcu memory");
 
 	ltq_rcu_membase = ioremap_nocache(res.start, resource_size(&res));

arch/mips/lantiq/xway/sysctrl.c

@@ -425,12 +425,12 @@ void __init ltq_soc_init(void)
 			of_address_to_resource(np_ebu, 0, &res_ebu))
 		panic("Failed to get core resources");
 
-	if ((request_mem_region(res_pmu.start, resource_size(&res_pmu),
-				res_pmu.name) < 0) ||
-		(request_mem_region(res_cgu.start, resource_size(&res_cgu),
-				res_cgu.name) < 0) ||
-		(request_mem_region(res_ebu.start, resource_size(&res_ebu),
-				res_ebu.name) < 0))
+	if (!request_mem_region(res_pmu.start, resource_size(&res_pmu),
+				res_pmu.name) ||
+		!request_mem_region(res_cgu.start, resource_size(&res_cgu),
+				res_cgu.name) ||
+		!request_mem_region(res_ebu.start, resource_size(&res_ebu),
+				res_ebu.name))
 		pr_err("Failed to request core resources");
 
 	pmu_membase = ioremap_nocache(res_pmu.start, resource_size(&res_pmu));