refactor CPUID detection code to use a struct

1 files changed, 22 insertions, 11 deletions

diff --git a/cpui-drv.c b/cpui-drv.c
index bcb6dba..445dc10 100644
--- a/cpui-drv.c
+++ b/cpui-drv.c
@@ -2,24 +2,35 @@
 
 #include <linux/module.h>
 
-static int __init cpui_init(void)
+struct cpui_info {
+	uint32_t cpuid_max;
+	char vendor_string[13];
+};
+
+static struct cpui_info __cpu;
+
+static void detect_cpu(struct cpui_info *cpu)
 {
-	char id_str[13];
-	uint32_t eax = 0, ebx, ecx, edx;
+	/* Get CPU Vendor ID String */
+	cpuid(0x00, (unsigned int *)&cpu->cpuid_max,
+		(unsigned int *)&cpu->vendor_string[0],
+		(unsigned int *)&cpu->vendor_string[8],
+		(unsigned int *)&cpu->vendor_string[4]);
+	cpu->vendor_string[12] = '\0';
+}
 
+static int __init cpui_init(void)
+{
 	if (!have_cpuid_p()) {
 		pr_err("CPUID instruction is NOT supported. Aborting.\n");
 		return 1;
 	}
-
-	cpuid(0, &eax, &ebx, &ecx, &edx);
 	pr_info("CPUID instruction is supported.\n");
-	pr_info("Maximum Input Value for Basic CPUID Information = %d\n", eax);
-	memcpy(&(id_str[0]), &ebx, 4);
-	memcpy(&(id_str[4]), &edx, 4);
-	memcpy(&(id_str[8]), &ecx, 4);
-	id_str[12] = '\0';
-	pr_info("Identity string = %s\n", id_str);
+
+	memset(&__cpu, 0, sizeof(__cpu));
+	detect_cpu(&__cpu);
+	pr_info("Maximum Input Value for Basic CPUID Information = %d\n", __cpu.cpuid_max);
+	pr_info("Identity string = %s\n", __cpu.vendor_string);
 	return 0;
 }