MIPS: lantiq: check the return value of kzalloc()

kzalloc() is a memory allocation function which can return NULL when
some internal memory errors happen. So it is better to check the
return value of it to prevent potential wrong memory access or
memory leak.

Signed-off-by: Xiaoke Wang <[e-mail]>
Signed-off-by: Thomas Bogendoerfer <[e-mail]>

arch/mips/lantiq/falcon/sysctrl.c

···
 {
 	struct clk *clk = kzalloc(sizeof(struct clk), GFP_KERNEL);
 
+	if (!clk)
+		return;
 	clk->cl.dev_id = dev;
 	clk->cl.con_id = NULL;
 	clk->cl.clk = clk;

arch/mips/lantiq/xway/gptu.c

···
 {
 	struct clk *clk = kzalloc(sizeof(struct clk), GFP_KERNEL);
 
+	if (!clk)
+		return;
 	clk->cl.dev_id = dev_name(dev);
 	clk->cl.con_id = con;
 	clk->cl.clk = clk;

arch/mips/lantiq/xway/sysctrl.c

···
 {
 	struct clk *clk = kzalloc(sizeof(struct clk), GFP_KERNEL);
 
+	if (!clk)
+		return;
 	clk->cl.dev_id = dev;
 	clk->cl.con_id = con;
 	clk->cl.clk = clk;
···
 {
 	struct clk *clk = kzalloc(sizeof(struct clk), GFP_KERNEL);
 
+	if (!clk)
+		return;
 	clk->cl.dev_id = dev;
 	clk->cl.con_id = con;
 	clk->cl.clk = clk;
···
 	struct clk *clk_ext = kzalloc(sizeof(struct clk), GFP_KERNEL);
 
 	/* main pci clock */
-	clk->cl.dev_id = "17000000.pci";
-	clk->cl.con_id = NULL;
-	clk->cl.clk = clk;
-	clk->rate = CLOCK_33M;
-	clk->rates = valid_pci_rates;
-	clk->enable = pci_enable;
-	clk->disable = pmu_disable;
-	clk->module = 0;
-	clk->bits = PMU_PCI;
-	clkdev_add(&clk->cl);
+	if (clk) {
+		clk->cl.dev_id = "17000000.pci";
+		clk->cl.con_id = NULL;
+		clk->cl.clk = clk;
+		clk->rate = CLOCK_33M;
+		clk->rates = valid_pci_rates;
+		clk->enable = pci_enable;
+		clk->disable = pmu_disable;
+		clk->module = 0;
+		clk->bits = PMU_PCI;
+		clkdev_add(&clk->cl);
+	}
 
 	/* use internal/external bus clock */
-	clk_ext->cl.dev_id = "17000000.pci";
-	clk_ext->cl.con_id = "external";
-	clk_ext->cl.clk = clk_ext;
-	clk_ext->enable = pci_ext_enable;
-	clk_ext->disable = pci_ext_disable;
-	clkdev_add(&clk_ext->cl);
+	if (clk_ext) {
+		clk_ext->cl.dev_id = "17000000.pci";
+		clk_ext->cl.con_id = "external";
+		clk_ext->cl.clk = clk_ext;
+		clk_ext->enable = pci_ext_enable;
+		clk_ext->disable = pci_ext_disable;
+		clkdev_add(&clk_ext->cl);
+	}
 }
 
 /* xway socs can generate clocks on gpio pins */
···
 		char *name;
 
 		name = kzalloc(sizeof("clkout0"), GFP_KERNEL);
+		if (!name)
+			continue;
 		sprintf(name, "clkout%d", i);
 
 		clk = kzalloc(sizeof(struct clk), GFP_KERNEL);
+		if (!clk) {
+			kfree(name);
+			continue;
+		}
 		clk->cl.dev_id = "1f103000.cgu";
 		clk->cl.con_id = name;
 		clk->cl.clk = clk;