1 files changed, 35 insertions, 30 deletions

diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index 86a2ee40078b..3808d9572619 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -284,7 +284,8 @@ static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
 
         if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT,
                                         PAGE_SIZE, vma->vm_page_prot)) {
-                printk(KERN_ERR "remap_pfn_range failed in hpet.c\n");
+                printk(KERN_ERR "%s: io_remap_pfn_range failed\n",
+                        __FUNCTION__);
                 return -EAGAIN;
         }
 
@@ -565,6 +566,17 @@ static struct file_operations hpet_fops = {
         .mmap = hpet_mmap,
 };
 
+static int hpet_is_known(struct hpet_data *hdp)
+{
+        struct hpets *hpetp;
+
+        for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
+                if (hpetp->hp_hpet_phys == hdp->hd_phys_address)
+                        return 1;
+
+        return 0;
+}
+
 EXPORT_SYMBOL(hpet_alloc);
 EXPORT_SYMBOL(hpet_register);
 EXPORT_SYMBOL(hpet_unregister);
@@ -730,11 +742,10 @@ static void hpet_register_interpolator(struct hpets *hpetp)
 #ifdef  CONFIG_TIME_INTERPOLATION
         struct time_interpolator *ti;
 
-        ti = kmalloc(sizeof(*ti), GFP_KERNEL);
+        ti = kzalloc(sizeof(*ti), GFP_KERNEL);
         if (!ti)
                 return;
 
-        memset(ti, 0, sizeof(*ti));
         ti->source = TIME_SOURCE_MMIO64;
         ti->shift = 10;
         ti->addr = &hpetp->hp_hpet->hpet_mc;
@@ -799,32 +810,29 @@ int hpet_alloc(struct hpet_data *hdp)
         struct hpets *hpetp;
         size_t siz;
         struct hpet __iomem *hpet;
-        static struct hpets *last = (struct hpets *)0;
+        static struct hpets *last = NULL;
         unsigned long period;
         unsigned long long temp;
 
         /*
          * hpet_alloc can be called by platform dependent code.
-         * if platform dependent code has allocated the hpet
-         * ACPI also reports hpet, then we catch it here.
+         * If platform dependent code has allocated the hpet that
+         * ACPI has also reported, then we catch it here.
          */
-        for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
-                if (hpetp->hp_hpet_phys == hdp->hd_phys_address) {
-                        printk(KERN_DEBUG "%s: duplicate HPET ignored\n",
-                                __FUNCTION__);
-                        return 0;
-                }
+        if (hpet_is_known(hdp)) {
+                printk(KERN_DEBUG "%s: duplicate HPET ignored\n",
+                        __FUNCTION__);
+                return 0;
+        }
 
         siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
                                       sizeof(struct hpet_dev));
 
-        hpetp = kmalloc(siz, GFP_KERNEL);
+        hpetp = kzalloc(siz, GFP_KERNEL);
 
         if (!hpetp)
                 return -ENOMEM;
 
-        memset(hpetp, 0, siz);
-
         hpetp->hp_which = hpet_nhpet++;
         hpetp->hp_hpet = hdp->hd_address;
         hpetp->hp_hpet_phys = hdp->hd_phys_address;
@@ -911,7 +919,6 @@ static acpi_status hpet_resources(struct acpi_resource *res, void *data)
         struct hpet_data *hdp;
         acpi_status status;
         struct acpi_resource_address64 addr;
-        struct hpets *hpetp;
 
         hdp = data;
 
@@ -924,13 +931,12 @@ static acpi_status hpet_resources(struct acpi_resource *res, void *data)
                 hdp->hd_phys_address = addr.min_address_range;
                 hdp->hd_address = ioremap(addr.min_address_range, size);
 
-                for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
-                        if (hpetp->hp_hpet_phys == hdp->hd_phys_address) {
-                                printk(KERN_DEBUG "%s: 0x%lx is busy\n",
-                                        __FUNCTION__, hdp->hd_phys_address);
-                                iounmap(hdp->hd_address);
-                                return -EBUSY;
-                        }
+                if (hpet_is_known(hdp)) {
+                        printk(KERN_DEBUG "%s: 0x%lx is busy\n",
+                                __FUNCTION__, hdp->hd_phys_address);
+                        iounmap(hdp->hd_address);
+                        return -EBUSY;
+                }
         } else if (res->id == ACPI_RSTYPE_FIXED_MEM32) {
                 struct acpi_resource_fixed_mem32 *fixmem32;
 
@@ -942,13 +948,12 @@ static acpi_status hpet_resources(struct acpi_resource *res, void *data)
                 hdp->hd_address = ioremap(fixmem32->range_base_address,
                                                 HPET_RANGE_SIZE);
 
-                for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
-                        if (hpetp->hp_hpet_phys == hdp->hd_phys_address) {
-                                printk(KERN_DEBUG "%s: 0x%lx is busy\n",
-                                        __FUNCTION__, hdp->hd_phys_address);
-                                iounmap(hdp->hd_address);
-                                return -EBUSY;
-                        }
+                if (hpet_is_known(hdp)) {
+                        printk(KERN_DEBUG "%s: 0x%lx is busy\n",
+                                __FUNCTION__, hdp->hd_phys_address);
+                        iounmap(hdp->hd_address);
+                        return -EBUSY;
+                }
         } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
                 struct acpi_resource_ext_irq *irqp;
                 int i;