Re: [PATCH] High resolution timer for cx88 remotes

2009-06-16 Thread Mauro Carvalho Chehab 
Em Sat, 23 May 2009 14:06:01 +0200
AH andrzej.ha...@wp.pl escreveu:

 Hi
 
 Some remotes requires short polling interval which in modern kernels is 
 below resolution of standard scheduler (schedule_delayed_work), this 
 causes problem of missed keystrokes. One of the solutions is to raise 
 kernel timer frequency, my proposition is to use high resolution timers 
 which are present in kernel since 2.6.16 (at least API AFAIK).
 I have encountered this problem on my Winfast 2000XP Expert, but after 
 checking cx88-input.c it seems that following cards can be affected also:
 WINFAST2000XP_EXPERT
 WINFAST_DTV1000
 WINFAST_TV2000_XP_GLOBAL
 PROLINK_PLAYTVPVR
 PIXELVIEW_PLAYTV_ULTRA_PRO
 PROLINK_PV_8000GT
 PROLINK_PV_GLOBAL_XTREME
 KWORLD_LTV883
 MSI_TVANYWHERE_MASTER
 
 Patched driver seems to work on my system, with kernel 2.6.28.
 I have removed kernel checks for versions below 2.6.20 - they were 
 because of API changes in scheduler.
 
 I have not tested it on older kernels.
 
 Regards
 AH
 
 diff -r 315bc4b65b4f linux/drivers/media/video/cx88/cx88-input.c
 --- a/linux/drivers/media/video/cx88/cx88-input.c   Sun May 17 
 12:28:55 2009 +
 +++ b/linux/drivers/media/video/cx88/cx88-input.c   Sat May 23 
 14:04:17 2009 +0200
 @@ -23,10 +23,10 @@
   */
 
  #include linux/init.h
 -#include linux/delay.h
  #include linux/input.h
  #include linux/pci.h
  #include linux/module.h
 +#include linux/hrtimer.h
 
  #include compat.h
  #include cx88.h
 @@ -49,7 +49,7 @@
 
 /* poll external decoder */
 int polling;
 -   struct delayed_work work;
 +   struct hrtimer timer;
 u32 gpio_addr;
 u32 last_gpio;
 u32 mask_keycode;
 @@ -144,31 +144,25 @@
 }
  }
 
 -#if LINUX_VERSION_CODE  KERNEL_VERSION(2,6,20)
 -static void cx88_ir_work(void *data)
 -#else
 -static void cx88_ir_work(struct work_struct *work)
 -#endif
 +enum hrtimer_restart cx88_ir_work(struct hrtimer *timer)
  {
 -#if LINUX_VERSION_CODE  KERNEL_VERSION(2,6,20)
 -   struct cx88_IR *ir = data;
 -#else
 -   struct cx88_IR *ir = container_of(work, struct cx88_IR, work.work);
 -#endif
 +   unsigned long missed;
 +   struct cx88_IR *ir = container_of(timer, struct cx88_IR, timer);
 
 cx88_ir_handle_key(ir);
 -   schedule_delayed_work(ir-work, msecs_to_jiffies(ir-polling));
 +   missed = hrtimer_forward_now(ir-timer, ktime_set(0, 
 ir-polling * 100));

Hmm... this patch got line wrapped. please fix it and re-send.

 +   if (missed  1)
 +   ir_dprintk(Missed ticks %ld\n, missed - 1);
 +
 +   return HRTIMER_RESTART;
  }
 
  void cx88_ir_start(struct cx88_core *core, struct cx88_IR *ir)
  {
 if (ir-polling) {
 -#if LINUX_VERSION_CODE  KERNEL_VERSION(2,6,20)
 -   INIT_DELAYED_WORK(ir-work, cx88_ir_work, ir);
 -#else
 -   INIT_DELAYED_WORK(ir-work, cx88_ir_work);
 -#endif
 -   schedule_delayed_work(ir-work, 0);
 +   hrtimer_init(ir-timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 +   ir-timer.function = cx88_ir_work;
 +   hrtimer_start(ir-timer, ktime_set(0, ir-polling * 
 100), HRTIMER_MODE_REL);
 }
 if (ir-sampling) {
 core-pci_irqmask |= PCI_INT_IR_SMPINT;
 @@ -185,7 +179,7 @@
 }
 
 if (ir-polling)
 -   cancel_delayed_work_sync(ir-work);
 +   hrtimer_cancel(ir-timer);
  }
 
  /* 
 -- */
 
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Cheers,
Mauro
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Re: [PATCH] High resolution timer for cx88 remotes

2009-06-16 Thread Trent Piepho 
On Tue, 16 Jun 2009, Mauro Carvalho Chehab wrote:
 Em Sat, 23 May 2009 14:06:01 +0200
 AH andrzej.ha...@wp.pl escreveu:
  Patched driver seems to work on my system, with kernel 2.6.28.
  I have removed kernel checks for versions below 2.6.20 - they were
  because of API changes in scheduler.

If you are going to break compatibility below 2.6.20 then you should add
the driver to versions.txt
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[PATCH] High resolution timer for cx88 remotes

2009-05-23 Thread AH 

Hi

Some remotes requires short polling interval which in modern kernels is 
below resolution of standard scheduler (schedule_delayed_work), this 
causes problem of missed keystrokes. One of the solutions is to raise 
kernel timer frequency, my proposition is to use high resolution timers 
which are present in kernel since 2.6.16 (at least API AFAIK).
I have encountered this problem on my Winfast 2000XP Expert, but after 
checking cx88-input.c it seems that following cards can be affected also:

WINFAST2000XP_EXPERT
WINFAST_DTV1000
WINFAST_TV2000_XP_GLOBAL
PROLINK_PLAYTVPVR
PIXELVIEW_PLAYTV_ULTRA_PRO
PROLINK_PV_8000GT
PROLINK_PV_GLOBAL_XTREME
KWORLD_LTV883
MSI_TVANYWHERE_MASTER

Patched driver seems to work on my system, with kernel 2.6.28.
I have removed kernel checks for versions below 2.6.20 - they were 
because of API changes in scheduler.


I have not tested it on older kernels.

Regards
AH

diff -r 315bc4b65b4f linux/drivers/media/video/cx88/cx88-input.c
--- a/linux/drivers/media/video/cx88/cx88-input.c   Sun May 17 
12:28:55 2009 +
+++ b/linux/drivers/media/video/cx88/cx88-input.c   Sat May 23 
14:04:17 2009 +0200

@@ -23,10 +23,10 @@
 */

#include linux/init.h
-#include linux/delay.h
#include linux/input.h
#include linux/pci.h
#include linux/module.h
+#include linux/hrtimer.h

#include compat.h
#include cx88.h
@@ -49,7 +49,7 @@

   /* poll external decoder */
   int polling;
-   struct delayed_work work;
+   struct hrtimer timer;
   u32 gpio_addr;
   u32 last_gpio;
   u32 mask_keycode;
@@ -144,31 +144,25 @@
   }
}

-#if LINUX_VERSION_CODE  KERNEL_VERSION(2,6,20)
-static void cx88_ir_work(void *data)
-#else
-static void cx88_ir_work(struct work_struct *work)
-#endif
+enum hrtimer_restart cx88_ir_work(struct hrtimer *timer)
{
-#if LINUX_VERSION_CODE  KERNEL_VERSION(2,6,20)
-   struct cx88_IR *ir = data;
-#else
-   struct cx88_IR *ir = container_of(work, struct cx88_IR, work.work);
-#endif
+   unsigned long missed;
+   struct cx88_IR *ir = container_of(timer, struct cx88_IR, timer);

   cx88_ir_handle_key(ir);
-   schedule_delayed_work(ir-work, msecs_to_jiffies(ir-polling));
+   missed = hrtimer_forward_now(ir-timer, ktime_set(0, 
ir-polling * 100));

+   if (missed  1)
+   ir_dprintk(Missed ticks %ld\n, missed - 1);
+
+   return HRTIMER_RESTART;
}

void cx88_ir_start(struct cx88_core *core, struct cx88_IR *ir)
{
   if (ir-polling) {
-#if LINUX_VERSION_CODE  KERNEL_VERSION(2,6,20)
-   INIT_DELAYED_WORK(ir-work, cx88_ir_work, ir);
-#else
-   INIT_DELAYED_WORK(ir-work, cx88_ir_work);
-#endif
-   schedule_delayed_work(ir-work, 0);
+   hrtimer_init(ir-timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+   ir-timer.function = cx88_ir_work;
+   hrtimer_start(ir-timer, ktime_set(0, ir-polling * 
100), HRTIMER_MODE_REL);

   }
   if (ir-sampling) {
   core-pci_irqmask |= PCI_INT_IR_SMPINT;
@@ -185,7 +179,7 @@
   }

   if (ir-polling)
-   cancel_delayed_work_sync(ir-work);
+   hrtimer_cancel(ir-timer);
}

/* 
-- */


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