Re: [PATCH] High resolution timer for cx88 remotes
On Tue, 16 Jun 2009, Mauro Carvalho Chehab wrote: > Em Sat, 23 May 2009 14:06:01 +0200 > AH 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 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] High resolution timer for cx88 remotes
Em Sat, 23 May 2009 14:06:01 +0200 AH 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 > -#include > #include > #include > #include > +#include > > #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); > } > > /* > -- */ > > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Cheers, Mauro -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH] High resolution timer for cx88 remotes
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 -#include #include #include #include +#include #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); } /* -- */ -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html