Re: [PATCH] HPET driver
From: Jeff Garzik
Date: Thu May 13 2004 - 18:22:24 EST
Robert Picco wrote:
diff -ruN -X /home/picco/losl/dontdiff
linux-2.6.6-orig/drivers/char/hpet.c linux-2.6.6-hpet/drivers/char/hpet.c
--- linux-2.6.6-orig/drivers/char/hpet.c 1969-12-31
19:00:00.000000000 -0500
+++ linux-2.6.6-hpet/drivers/char/hpet.c 2004-05-10
15:43:48.000000000 -0400
@@ -0,0 +1,1116 @@
run this through Lindent... non-standard indentation
+/*
+ * Intel & MS High Precision Event Timer Implementation.
+ * Contributors:
+ * Venki Pallipadi
+ * Bob Picco
+ */
+
+#include <linux/config.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/major.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/proc_fs.h>
+#include <linux/spinlock.h>
+#include <linux/sysctl.h>
+#include <linux/wait.h>
+#include <linux/bcd.h>
+#include <linux/seq_file.h>
+
+#include <asm/current.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/bitops.h>
+#include <asm/div64.h>
+
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+#include <linux/hpet.h>
+
+/*
+ * The High Precision Event Timer driver.
+ * This driver is closely modelled after the rtc.c driver.
+ * http://www.intel.com/labs/platcomp/hpet/hpetspec.htm
+ */
+#define HPET_USER_FREQ (64)
+#define HPET_DRIFT (500)
+
+static u32 hpet_ntimer, hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
+static char hpetname[] = "hpet/XX";
+
+/* A lock for concurrent access by app and isr hpet activity. */
+static spinlock_t hpet_lock = SPIN_LOCK_UNLOCKED;
+/* A lock for concurrent intermodule access to hpet and isr hpet
activity. */
+static spinlock_t hpet_task_lock = SPIN_LOCK_UNLOCKED;
+
+struct hpet_dev {
+ struct hpets *hd_hpets;
+ volatile struct hpet *hd_hpet;
+ volatile struct hpet_timer
+ *hd_timer;
+ unsigned long hd_ireqfreq;
+ unsigned long hd_irqdata;
+ wait_queue_head_t hd_waitqueue;
+ struct fasync_struct *hd_async_queue;
+ struct hpet_task *hd_task;
+ unsigned int hd_flags;
+ unsigned int hd_irq;
+ unsigned int hd_hdwirq;
+ int hd_minor;
+};
kill the 'volatile', it's preferred to put barriers and such in the code
where they are needed.
+struct hpets {
+ struct hpets *hp_next;
+ volatile struct hpet *hp_hpet;
+ unsigned long hp_period;
+ unsigned long hp_delta;
+ unsigned int hp_ntimer;
+ unsigned int hp_which;
+ struct hpet_dev hp_dev[1];
+};
+
+static struct hpets *hpets;
+
+#define HPET_OPEN 0x0001
+#define HPET_IE 0x0002 /* interrupt enabled */
+#define HPET_PERIODIC 0x0004
+
+static irqreturn_t
+hpet_interrupt (int irq, void *data, struct pt_regs *regs)
+{
+ struct hpet_dev *devp;
+ unsigned long isr;
+
+ devp = data;
+
+ spin_lock(&hpet_lock);
+ devp->hd_irqdata++;
+
+ if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
+ unsigned long m, t;
+
+ t = devp->hd_ireqfreq;
+ m = devp->hd_hpet->hpet_mc;
+ devp->hd_timer->hpet_compare = t + m + devp->hd_hpets->hp_delta;
+ }
+
+ isr = (1 << (devp - devp->hd_hpets->hp_dev));
+ devp->hd_hpet->hpet_isr = isr;
+ spin_unlock(&hpet_lock);
+
+ spin_lock(&hpet_task_lock);
+ if (devp->hd_task)
+ devp->hd_task->ht_func(devp->hd_task->ht_data);
+ spin_unlock(&hpet_task_lock);
+
+ wake_up_interruptible(&devp->hd_waitqueue);
+
+ kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
+
+ return IRQ_HANDLED;
+}
+
+static struct hpet_dev *
+hpet_minor_to_dev (int minor)
+{
+ struct hpets *hpetp;
+ int i;
+
+ for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
+ for (i = 0; i < hpetp->hp_ntimer; i++)
+ if (hpetp->hp_dev[i].hd_minor == minor)
+ return &hpetp->hp_dev[i];
+ return 0;
+}
+
+static int
+hpet_open (struct inode *inode, struct file *file)
+{
+ struct hpet_dev *devp;
+
+ devp = hpet_minor_to_dev(MINOR(inode->i_rdev));
locking of hpets?
+ vma->vm_flags |= (VM_IO | VM_SHM | VM_LOCKED);
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ addr = __pa(addr);
where did these flags come from? don't you just want VM_RESERVED?
+ if (remap_page_range(vma, vma->vm_start, addr, PAGE_SIZE,
vma->vm_page_prot)) {
+ printk(KERN_ERR "remap_page_range failed in hpet.c\n");
+ return -EAGAIN;
+ }
why not ->nopage like in sound/oss/via82cxxx_audio.c?
+static int
+hpet_release (struct inode *inode, struct file *file)
+{
+ struct hpet_dev *devp;
+ volatile struct hpet_timer *timer;
+
+ devp = file->private_data;
+ timer = devp->hd_timer;
+
+ spin_lock_irq(&hpet_lock);
+
+ timer->hpet_config &= ~Tn_INT_ENB_CNF_MASK;
+
+ if (devp->hd_irq) {
+ free_irq(devp->hd_irq, devp);
+ devp->hd_irq = 0;
+ }
+
+ devp->hd_ireqfreq = 0;
+
+ if (devp->hd_flags & HPET_PERIODIC && timer->hpet_config &
Tn_TYPE_CNF_MASK) {
+ unsigned long v;
+
+ v = timer->hpet_config;
+ v ^= Tn_TYPE_CNF_MASK;
+ timer->hpet_config = v;
+ }
+
+ devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
+ spin_unlock_irq(&hpet_lock);
+
+ if (file->f_flags & FASYNC)
+ hpet_fasync(-1, file, 0);
+
+ file->private_data = 0;
+ return 0;
+}
+
+static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int);
+
+static int
+hpet_ioctl (struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
+{
+ struct hpet_dev *devp;
+
+ devp = file->private_data;
+ return hpet_ioctl_common(devp, cmd, arg, 0);
+}
+
+static int
+hpet_ioctl_ieon (struct hpet_dev *devp)
+{
+ volatile struct hpet_timer *timer;
+ volatile struct hpet *hpet;
+ struct hpets *hpetp;
+ int irq;
+ unsigned long g, v, t, m;
+ unsigned long flags, isr;
+
+ timer = devp->hd_timer;
+ hpet = devp->hd_hpet;
+ hpetp = devp->hd_hpets;
+
+ v = timer->hpet_config;
+ spin_lock_irq(&hpet_lock);
+
+ if (devp->hd_flags & HPET_IE) {
+ spin_unlock_irq(&hpet_lock);
+ return -EBUSY;
+ }
+
+ devp->hd_flags |= HPET_IE;
+ spin_unlock_irq(&hpet_lock);
+
+ t = timer->hpet_config;
+ irq = devp->hd_hdwirq;
+
+ if (irq) {
+ char name[7];
+
+ sprintf(name, "hpet%d", (int) (devp - hpetp->hp_dev));
+
+ if (request_irq(irq, hpet_interrupt, SA_INTERRUPT, name, (void
*) devp)) {
+ printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
+ irq = 0;
+ }
+ }
+
+ if (irq == 0) {
+ spin_lock_irq(&hpet_lock);
+ devp->hd_flags ^= HPET_IE;
+ spin_unlock_irq(&hpet_lock);
+ return -EIO;
+ }
+
+ devp->hd_irq = irq;
+ t = devp->hd_ireqfreq;
+ v = timer->hpet_config;
+ g = v | Tn_INT_ENB_CNF_MASK;
+
+ if (devp->hd_flags & HPET_PERIODIC) {
+ timer->hpet_compare = t;
+ g |= Tn_TYPE_CNF_MASK;
+ v |= Tn_TYPE_CNF_MASK;
+ timer->hpet_config = v;
+ v |= Tn_VAL_SET_CNF_MASK;
+ timer->hpet_config = v;
+ local_irq_save(flags);
+ m = hpet->hpet_mc;
+ timer->hpet_compare = t + m + hpetp->hp_delta;
+ } else {
+ local_irq_save(flags);
+ m = hpet->hpet_mc;
+ timer->hpet_compare = t + m + hpetp->hp_delta;
+ }
+
+ isr = (1 << (devp - hpets->hp_dev));
+ hpet->hpet_isr = isr;
+ timer->hpet_config = g;
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static inline unsigned long
+hpet_time_div (unsigned long dis)
+{
+ unsigned long long m = 1000000000000000ULL;
+
+ do_div(m, dis);
+
+ return (unsigned long) m;
+}
+
+static int
+hpet_ioctl_common (struct hpet_dev *devp, int cmd, unsigned long arg,
int kernel)
+{
+ volatile struct hpet_timer *timer;
+ volatile struct hpet *hpet;
+ struct hpets *hpetp;
+ int err;
+ unsigned long v;
+
+ switch (cmd) {
+ case HPET_IE_OFF:
+ case HPET_INFO:
+ case HPET_EPI:
+ case HPET_DPI:
+ case HPET_IRQFREQ:
+ timer = devp->hd_timer;
+ hpet = devp->hd_hpet;
+ hpetp = devp->hd_hpets;
+ break;
+ case HPET_IE_ON:
+ return hpet_ioctl_ieon(devp);
+ default:
+ return -EINVAL;
+ }
+
+ err = 0;
+
+ switch (cmd) {
+ case HPET_IE_OFF:
+ if ((devp->hd_flags & HPET_IE) == 0)
+ break;
+ v = timer->hpet_config;
+ v &= ~Tn_INT_ENB_CNF_MASK;
+ timer->hpet_config = v;
+ if (devp->hd_irq) {
+ free_irq(devp->hd_irq, devp);
+ devp->hd_irq = 0;
+ }
+ devp->hd_flags ^= HPET_IE;
+ break;
do you really want to be freeing the irq outside of the open-close model?
+ case HPET_INFO:
+ {
+ struct hpet_info info;
+
+ info.hi_ireqfreq = hpet_time_div(hpetp->hp_period *
+ devp->hd_ireqfreq);
+ info.hi_flags = timer->hpet_config & Tn_PER_INT_CAP_MASK;
+ if (copy_to_user((void *) arg, &info , sizeof (info)))
+ err = -EFAULT;
+ break;
+ }
+ case HPET_EPI:
+ v = timer->hpet_config;
+ if ((v & Tn_PER_INT_CAP_MASK) == 0) {
+ err = -ENXIO;
+ break;
+ }
+ devp->hd_flags |= HPET_PERIODIC;
+ break;
+ case HPET_DPI:
+ v = timer->hpet_config;
+ if ((v & Tn_PER_INT_CAP_MASK) == 0) {
+ err = -ENXIO;
+ break;
+ }
+ if (devp->hd_flags & HPET_PERIODIC &&
+ timer->hpet_config & Tn_TYPE_CNF_MASK) {
+ v = timer->hpet_config;
+ v ^= Tn_TYPE_CNF_MASK;
+ timer->hpet_config = v;
+ }
+ devp->hd_flags &= ~HPET_PERIODIC;
+ break;
+ case HPET_IRQFREQ:
+ if (!kernel && (arg > hpet_max_freq) &&
+ !capable(CAP_SYS_RESOURCE)) {
+ err = -EACCES;
+ break;
+ }
+
+ if (arg & (arg - 1)) {
+ err = -EINVAL;
+ break;
+ }
+
+ devp->hd_ireqfreq = hpet_time_div(hpetp->hp_period * arg);
+ }
+
+ return err;
+}
+
+static struct file_operations hpet_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .read = hpet_read,
+ .poll = hpet_poll,
+ .ioctl = hpet_ioctl,
+ .open = hpet_open,
+ .release = hpet_release,
+ .fasync = hpet_fasync,
+ .mmap = hpet_mmap,
+};
+
+EXPORT_SYMBOL(hpet_alloc);
+EXPORT_SYMBOL(hpet_register);
+EXPORT_SYMBOL(hpet_unregister);
+EXPORT_SYMBOL(hpet_control);
+
+int
+hpet_register (struct hpet_task *tp, int periodic)
+{
+ unsigned int i;
+ u64 mask;
+ volatile struct hpet_timer *timer;
+ struct hpet_dev *devp;
+ struct hpets *hpetp;
+
+ switch (periodic) {
+ case 1:
+ mask = Tn_PER_INT_CAP_MASK;
+ break;
+ case 0:
+ mask = 0;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spin_lock_irq(&hpet_task_lock);
+ spin_lock(&hpet_lock);
+
+ for (devp = 0, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
+ for (timer = hpetp->hp_hpet->hpet_timers, i = 0; i <
hpetp->hp_ntimer; i++, timer++) {
+ if ((timer->hpet_config & Tn_PER_INT_CAP_MASK) != mask)
+ continue;
+
+ devp = &hpetp->hp_dev[i];
+
+ if (devp->hd_flags & HPET_OPEN || devp->hd_task) {
+ devp = 0;
+ continue;
+ }
+
+ tp->ht_opaque = devp;
+ devp->hd_task = tp;
+ break;
+ }
+
+ spin_unlock(&hpet_lock);
+ spin_unlock_irq(&hpet_task_lock);
+
+ if (tp->ht_opaque)
+ return 0;
+ else
+ return -EBUSY;
+}
+
+static inline int
+hpet_tpcheck (struct hpet_task *tp)
+{
+ struct hpet_dev *devp;
+ struct hpets *hpetp;
+
+ devp = tp->ht_opaque;
+
+ if (!devp)
+ return -ENXIO;
+
+ for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
+ if (devp >= hpetp->hp_dev && devp < (hpetp->hp_dev +
hpetp->hp_ntimer) &&
+ devp->hd_hpet == hpetp->hp_hpet)
+ return 0;
+
+ return -ENXIO;
+}
+
+
+int
+hpet_unregister (struct hpet_task *tp)
+{
+ struct hpet_dev *devp;
+ volatile struct hpet_timer *timer;
+ int err;
+
+ if ((err = hpet_tpcheck(tp)))
+ return err;
+
+ spin_lock_irq(&hpet_task_lock);
+ spin_lock(&hpet_lock);
+
+ devp = tp->ht_opaque;
+ if (devp->hd_task != tp) {
+ spin_unlock(&hpet_lock);
+ spin_unlock_irq(&hpet_task_lock);
+ return -ENXIO;
+ }
+
+ timer = devp->hd_timer;
+ timer->hpet_config &= ~Tn_INT_ENB_CNF_MASK;
+ devp->hd_flags &= ~( HPET_IE | HPET_PERIODIC);
+ devp->hd_task = 0;
+ spin_unlock(&hpet_lock);
+ spin_unlock_irq(&hpet_task_lock);
+
+ return 0;
+}
+
+int
+hpet_control (struct hpet_task *tp, unsigned int cmd, unsigned long arg)
+{
+ struct hpet_dev *devp;
+ int err;
+
+ if ((err = hpet_tpcheck(tp)))
+ return err;
+
+ spin_lock_irq(&hpet_lock);
+ devp = tp->ht_opaque;
+ if (devp->hd_task != tp) {
+ spin_unlock_irq(&hpet_lock);
+ return -ENXIO;
+ }
+ spin_unlock_irq(&hpet_lock);
+ return hpet_ioctl_common(devp, cmd, arg, 1);
+}
+
+
+
+#ifdef CONFIG_TIME_INTERPOLATION
+
+static unsigned long hpet_offset, last_wall_hpet;
+static long hpet_nsecs_per_cycle, hpet_cycles_per_sec;
+
+static unsigned long
+hpet_getoffset (void)
+{
+ return hpet_offset + (hpets->hp_hpet->hpet_mc - last_wall_hpet) *
hpet_nsecs_per_cycle;
+}
+
+static void
+hpet_update (long delta)
+{
+ unsigned long mc;
+ unsigned long offset;
+ volatile struct hpet *hpet;
+
+ hpet = hpets->hp_hpet;
+ mc = hpet->hpet_mc;
+ offset = hpet_offset + (mc - last_wall_hpet) * hpet_nsecs_per_cycle;
+
+ if (delta < 0 || (unsigned long) delta < offset)
+ hpet_offset = offset - delta;
+ else
+ hpet_offset = 0;
+ last_wall_hpet = mc;
+}
+
+static void
+hpet_reset (void)
+{
+ volatile struct hpet *hpet;
+
+ hpet = hpets->hp_hpet;
+ hpet_offset = 0;
+ last_wall_hpet = hpet->hpet_mc;
+}
+
+static struct time_interpolator hpet_interpolator = {
+ .get_offset = hpet_getoffset,
+ .update = hpet_update,
+ .reset = hpet_reset
+};
+
+#endif
+
+static ctl_table hpet_table[] = {
+ {
+ .ctl_name = 1,
+ .procname = "max-user-freq",
+ .data = &hpet_max_freq,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ { .ctl_name = 0 }
+};
+
+static ctl_table hpet_root[] = {
+ {
+ .ctl_name = 1,
+ .procname = "hpet",
+ .maxlen = 0,
+ .mode = 0555,
+ .child = hpet_table,
+ },
+ { .ctl_name = 0 }
+};
+
+static ctl_table dev_root[] = {
+ {
+ .ctl_name = CTL_DEV,
+ .procname = "dev",
+ .maxlen = 0,
+ .mode = 0555,
+ .child = hpet_root,
+ },
+ { .ctl_name = 0 }
+};
+
+static struct ctl_table_header *sysctl_header;
+
+static void *
+hpet_start (struct seq_file *s, loff_t *pos)
+{
+ struct hpets *hpetp;
+ loff_t n;
+
+ for (n = *pos, hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
+ if (!n--)
+ return hpetp;
+
+ return 0;
+}
+
+static void *
+hpet_next (struct seq_file *s, void *v, loff_t *pos)
+{
+ struct hpets *hpetp;
+
+ hpetp = v;
+ ++*pos;
+ return hpetp->hp_next;
+}
+
+static void
+hpet_stop (struct seq_file *s, void *v)
+{
+ return;
+}
+
+static int
+hpet_show (struct seq_file *s, void *v)
+{
+ struct hpets *hpetp;
+ volatile struct hpet *hpet;
+ u64 cap, vendor, period;
+
+ hpetp = v;
+ hpet = hpetp->hp_hpet;
+
+ cap = hpet->hpet_cap;
+ period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
+ HPET_COUNTER_CLK_PERIOD_SHIFT;
+ vendor = (cap & HPET_VENDOR_ID_MASK) >> HPET_VENDOR_ID_SHIFT;
+
+ seq_printf(s, "HPET%d period = %d 10**-15 vendor = 0x%x number
timer = %d\n",
+ hpetp->hp_which, (u32) period, (u32) vendor, hpetp->hp_ntimer);
+
+ return 0;
+}
+
+static struct seq_operations hpet_seq_ops = {
+ .start = hpet_start,
+ .next = hpet_next,
+ .stop = hpet_stop,
+ .show = hpet_show
+};
+
+static int
+hpet_proc_open (struct inode *inode, struct file *file)
+{
+ return seq_open(file, &hpet_seq_ops);
+}
+
+static struct file_operations hpet_proc_fops = {
+ .open = hpet_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release
+};
+
+
+/*
+ * Adjustment for when arming the timer with
+ * initial conditions. That is, main counter
+ * ticks expired before interrupts are enabled.
+ */
+#define TICK_CALIBRATE (1000UL)
+
+static unsigned long __init
+hpet_calibrate (struct hpets *hpetp)
+{
+ volatile struct hpet_timer *timer;
+ unsigned long t, m, count, i, flags, start;
+ struct hpet_dev *devp;
+ int j;
+ volatile struct hpet *hpet;
+
+ for (timer = 0, j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer;
j++, devp++)
+ if ((devp->hd_flags & HPET_OPEN) == 0) {
+ timer = devp->hd_timer;
+ break;
+ }
+
+ if (!timer)
+ return 0;
+
+ hpet = hpets->hp_hpet;
+ t = timer->hpet_compare;
+
+ i = 0;
+ count = hpet_time_div(hpetp->hp_period * TICK_CALIBRATE);
+
+ local_irq_save(flags);
+
+ start = hpet->hpet_mc;
+
+ do {
+ m = hpet->hpet_mc;
+ timer->hpet_compare = t + m + hpetp->hp_delta;
+ } while (i++, (m - start) < count);
+
+ local_irq_restore(flags);
+
+ return (m - start) / i;
+}
+
+static void __init
+hpet_init_chrdev (void)
+{
+ static int once;
+
+ if (!once++ && register_chrdev(HPET_MAJOR, "hpet", &hpet_fops))
+ panic("unable to to major %d for hpet device", HPET_MAJOR);
+
+ return;
+}
+
+static void __init
+hpet_post_platform (void)
+{
+ struct hpets *hpetp;
+ u32 i, ntimer;
+ struct hpet_dev *devp;
+
+ hpet_init_chrdev();
+
+ for (ntimer = 0, hpetp = hpets; hpetp; hpetp = hpetp->hp_next,
ntimer++)
+ for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++,
devp++) {
+
+ if (devp->hd_flags & HPET_OPEN)
+ continue;
+
+ sprintf(&hpetname[5], "%d", ntimer);
+ devfs_mk_cdev(MKDEV(HPET_MAJOR, ntimer),
+ S_IFCHR|S_IRUSR|S_IWUSR, hpetname);
+ init_waitqueue_head(&devp->hd_waitqueue);
+ }
+
+ return;
+}
+
+int __init
+hpet_alloc (struct hpet_data *hdp)
+{
+ u64 cap, mcfg;
+ struct hpet_dev *devp;
+ u32 i, ntimer;
+ struct hpets *hpetp;
+ size_t siz;
+ volatile struct hpet *hpet;
+ static struct hpets *last __initdata = (struct hpets *) 0;
+
+ for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
+ if (hpetp->hp_hpet == (struct hpet *) (hdp->hd_address))
+ return 0;
+
+ siz = sizeof (struct hpets) + ((hdp->hd_nirqs - 1) *
+ sizeof (struct hpet_dev));
+
+ hpetp = kmalloc(siz, GFP_KERNEL);
+
+ if (!hpetp)
+ return -ENOMEM;
+
+ memset(hpetp, 0, siz);
+
+ hpetp->hp_which = hpet_nhpet++;
+ hpetp->hp_hpet = (struct hpet *) hdp->hd_address;
+
+ if (last)
+ last->hp_next = hpetp;
+ else
+ hpets = hpetp;
+
+ last = hpetp;
+
+ hpetp->hp_ntimer = hdp->hd_nirqs;
+
+ for (i = 0; i < hdp->hd_nirqs; i++)
+ hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
+
+ hpet = hpetp->hp_hpet;
+
+ cap = hpet->hpet_cap;
+
+ ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT)
+ 1;
+
+ if (!ntimer) {
+ printk(KERN_WARNING "hpet: no timers in config data\n");
+ return -ENODEV;
+ }
+ else if (hpetp->hp_ntimer != ntimer) {
+ printk(KERN_WARNING "hpet: number irqs doesn't agree"
+ " with number of timers\n");
+ return -ENODEV;
+ }
+
+ hpetp->hp_period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
+ HPET_COUNTER_CLK_PERIOD_SHIFT;
+
+ mcfg = hpet->hpet_config;
+ if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
+ hpet->hpet_mc = 0L;
+ mcfg |= HPET_ENABLE_CNF_MASK;
+ hpet->hpet_config = mcfg;
+ }
+
+ /*
+ * Create character devices and init wait queue.
+ * If this is a platform call, then device initialization
+ * occurs during startup call to hpet_init.
+ */
+ if (hdp->hd_flags ^ HPET_DATA_PLATFORM)
+ hpet_init_chrdev();
+
+ for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++,
hpet_ntimer++, devp++) {
+ unsigned long v;
+ volatile struct hpet_timer *timer;
+
+ timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
+ v = timer->hpet_config;
+
+ devp->hd_hpets = hpetp;
+ devp->hd_hpet = hpet;
+ devp->hd_timer = timer;
+
+ devp->hd_minor = hpet_ntimer;
+
+ if (hdp->hd_state & (1 << i)) {
+ devp->hd_flags = HPET_OPEN;
+ continue;
+ }
+
+ if (hdp->hd_flags & HPET_DATA_PLATFORM)
+ continue;
+
+ sprintf(&hpetname[5], "%d", hpet_ntimer);
+ devfs_mk_cdev(MKDEV(HPET_MAJOR, hpet_ntimer),
+ S_IFCHR|S_IRUSR|S_IWUSR, hpetname);
+ init_waitqueue_head(&devp->hd_waitqueue);
+ }
+
+ hpetp->hp_delta = hpet_calibrate(hpetp);
+
+ return 0;
+}
+
+static acpi_status __init
+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;
+
+ status = acpi_resource_to_address64(res, &addr);
+
+ if (ACPI_SUCCESS(status)) {
+ unsigned long size;
+
+ size = addr.max_address_range - addr.min_address_range + 1;
+ hdp->hd_address = (unsigned long)
ioremap(addr.min_address_range, size);
+
+ for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
+ if (hpetp->hp_hpet == (struct hpet *) (hdp->hd_address))
+ return -EBUSY;
+ }
+ else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
+ struct acpi_resource_ext_irq *irqp;
+ int i;
+
+ irqp = &res->data.extended_irq;
+
+ if (irqp->number_of_interrupts > 0) {
+ hdp->hd_nirqs = irqp->number_of_interrupts;
+
+ for (i = 0; i < hdp->hd_nirqs; i++)
+#ifdef CONFIG_IA64
+ hdp->hd_irq[i] = acpi_register_irq(irqp->interrupts[i],
+ irqp->active_high_low, irqp->edge_level);
+#else
+ hdp->hd_irq[i] = irqp->interrupts[i];
+#endif
+ }
+ }
+
+ return AE_OK;
+}
+
+static int __init
+hpet_acpi_add (struct acpi_device *device)
+{
+ acpi_status result;
+ struct hpet_data data;
+
+ memset(&data, 0, sizeof(data));
+
+ result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
hpet_resources, &data);
+
+ if (ACPI_FAILURE(result))
+ return -ENODEV;
+
+ if (!data.hd_address || !data.hd_nirqs) {
+ printk("%s: no address or irqs in _CRS\n", __FUNCTION__);
+ return -ENODEV;
+ }
+
+ return hpet_alloc(&data);
+}
+
+static int __init
+hpet_acpi_remove (struct acpi_device *device, int type)
+{
+ return 0;
+}
+
+static struct acpi_driver hpet_acpi_driver __initdata = {
+ .name = "hpet",
+ .class = "",
+ .ids = "PNP0103",
+ .ops = {
+ .add = hpet_acpi_add,
+ .remove = hpet_acpi_remove,
+ },
+};
+
+
+
+static int __init
+hpet_init (void)
+{
+ struct proc_dir_entry *entry;
+
+ if (hpets)
+ hpet_post_platform();
+
+ (void) acpi_bus_register_driver(&hpet_acpi_driver);
+
+ if (hpets) {
+ entry = create_proc_entry("driver/hpet", 0, 0);
+
+ if (entry)
+ entry->proc_fops = &hpet_proc_fops;
+
+ sysctl_header = register_sysctl_table(dev_root, 0);
+
+#ifdef CONFIG_TIME_INTERPOLATION
+ {
+ volatile struct hpet *hpet;
+
+ hpet = hpets->hp_hpet;
+ hpet_cycles_per_sec = hpet_time_div(hpets->hp_period);
+ hpet_interpolator.frequency = hpet_cycles_per_sec;
+ hpet_interpolator.drift = hpet_cycles_per_sec *
+ HPET_DRIFT / 1000000;
+ hpet_nsecs_per_cycle = 1000000000 / hpet_cycles_per_sec;
+ register_time_interpolator(&hpet_interpolator);
+ }
+#endif
+ return 0;
+ }
+ else
+ return -ENODEV;
+}
+
+static void __exit
+hpet_exit (void)
+{
+ acpi_bus_unregister_driver(&hpet_acpi_driver);
+
+ if (hpets) {
+ unregister_sysctl_table(sysctl_header);
+ remove_proc_entry("driver/hpet", NULL);
+ }
+
+ return;
+}
Finally, would prefer sysfs use to procfs.
No major objections though.
Jeff
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/