1 files changed, 55 insertions, 35 deletions

diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index 0be700f4e8fd..4c16778e3f84 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -29,6 +29,7 @@
 #include <linux/bcd.h>
 #include <linux/seq_file.h>
 #include <linux/bitops.h>
+#include <linux/clocksource.h>
 
 #include <asm/current.h>
 #include <asm/uaccess.h>
@@ -51,8 +52,37 @@
 
 #define HPET_RANGE_SIZE         1024    /* from HPET spec */
 
+#if BITS_PER_LONG == 64
+#define write_counter(V, MC)    writeq(V, MC)
+#define read_counter(MC)        readq(MC)
+#else
+#define write_counter(V, MC)    writel(V, MC)
+#define read_counter(MC)        readl(MC)
+#endif
+
 static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
 
+/* This clocksource driver currently only works on ia64 */
+#ifdef CONFIG_IA64
+static void __iomem *hpet_mctr;
+
+static cycle_t read_hpet(void)
+{
+        return (cycle_t)read_counter((void __iomem *)hpet_mctr);
+}
+
+static struct clocksource clocksource_hpet = {
+        .name           = "hpet",
+        .rating         = 250,
+        .read           = read_hpet,
+        .mask           = CLOCKSOURCE_MASK(64),
+        .mult           = 0, /*to be caluclated*/
+        .shift          = 10,
+        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+static struct clocksource *hpet_clocksource;
+#endif
+
 /* A lock for concurrent access by app and isr hpet activity. */
 static DEFINE_SPINLOCK(hpet_lock);
 /* A lock for concurrent intermodule access to hpet and isr hpet activity. */
@@ -79,7 +109,7 @@ struct hpets {
         struct hpets *hp_next;
         struct hpet __iomem *hp_hpet;
         unsigned long hp_hpet_phys;
-        struct time_interpolator *hp_interpolator;
+        struct clocksource *hp_clocksource;
         unsigned long long hp_tick_freq;
         unsigned long hp_delta;
         unsigned int hp_ntimer;
@@ -94,13 +124,6 @@ static struct hpets *hpets;
 #define HPET_PERIODIC           0x0004
 #define HPET_SHARED_IRQ         0x0008
 
-#if BITS_PER_LONG == 64
-#define write_counter(V, MC)    writeq(V, MC)
-#define read_counter(MC)        readq(MC)
-#else
-#define write_counter(V, MC)    writel(V, MC)
-#define read_counter(MC)        readl(MC)
-#endif
 
 #ifndef readq
 static inline unsigned long long readq(void __iomem *addr)
@@ -737,27 +760,6 @@ static ctl_table dev_root[] = {
 
 static struct ctl_table_header *sysctl_header;
 
-static void hpet_register_interpolator(struct hpets *hpetp)
-{
-#ifdef  CONFIG_TIME_INTERPOLATION
-        struct time_interpolator *ti;
-
-        ti = kzalloc(sizeof(*ti), GFP_KERNEL);
-        if (!ti)
-                return;
-
-        ti->source = TIME_SOURCE_MMIO64;
-        ti->shift = 10;
-        ti->addr = &hpetp->hp_hpet->hpet_mc;
-        ti->frequency = hpetp->hp_tick_freq;
-        ti->drift = HPET_DRIFT;
-        ti->mask = -1;
-
-        hpetp->hp_interpolator = ti;
-        register_time_interpolator(ti);
-#endif
-}
-
 /*
  * Adjustment for when arming the timer with
  * initial conditions.  That is, main counter
@@ -909,7 +911,19 @@ int hpet_alloc(struct hpet_data *hdp)
         }
 
         hpetp->hp_delta = hpet_calibrate(hpetp);
-        hpet_register_interpolator(hpetp);
+
+/* This clocksource driver currently only works on ia64 */
+#ifdef CONFIG_IA64
+        if (!hpet_clocksource) {
+                hpet_mctr = (void __iomem *)&hpetp->hp_hpet->hpet_mc;
+                CLKSRC_FSYS_MMIO_SET(clocksource_hpet.fsys_mmio, hpet_mctr);
+                clocksource_hpet.mult = clocksource_hz2mult(hpetp->hp_tick_freq,
+                                                clocksource_hpet.shift);
+                clocksource_register(&clocksource_hpet);
+                hpetp->hp_clocksource = &clocksource_hpet;
+                hpet_clocksource = &clocksource_hpet;
+        }
+#endif
 
         return 0;
 }
@@ -932,14 +946,14 @@ static acpi_status hpet_resources(struct acpi_resource *res, void *data)
                         printk(KERN_DEBUG "%s: 0x%lx is busy\n",
                                 __FUNCTION__, hdp->hd_phys_address);
                         iounmap(hdp->hd_address);
-                        return -EBUSY;
+                        return AE_ALREADY_EXISTS;
                 }
         } else if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
                 struct acpi_resource_fixed_memory32 *fixmem32;
 
                 fixmem32 = &res->data.fixed_memory32;
                 if (!fixmem32)
-                        return -EINVAL;
+                        return AE_NO_MEMORY;
 
                 hdp->hd_phys_address = fixmem32->address;
                 hdp->hd_address = ioremap(fixmem32->address,
@@ -949,7 +963,7 @@ static acpi_status hpet_resources(struct acpi_resource *res, void *data)
                         printk(KERN_DEBUG "%s: 0x%lx is busy\n",
                                 __FUNCTION__, hdp->hd_phys_address);
                         iounmap(hdp->hd_address);
-                        return -EBUSY;
+                        return AE_ALREADY_EXISTS;
                 }
         } else if (res->type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ) {
                 struct acpi_resource_extended_irq *irqp;
@@ -995,13 +1009,19 @@ static int hpet_acpi_add(struct acpi_device *device)
 
 static int hpet_acpi_remove(struct acpi_device *device, int type)
 {
-        /* XXX need to unregister interpolator, dealloc mem, etc */
+        /* XXX need to unregister clocksource, dealloc mem, etc */
         return -EINVAL;
 }
 
+static const struct acpi_device_id hpet_device_ids[] = {
+        {"PNP0103", 0},
+        {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, hpet_device_ids);
+
 static struct acpi_driver hpet_acpi_driver = {
         .name = "hpet",
-        .ids = "PNP0103",
+        .ids = hpet_device_ids,
         .ops = {
                 .add = hpet_acpi_add,
                 .remove = hpet_acpi_remove,