| Message ID | 20201128165728.29756-1-sean@mess.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: mtk-cir: fix calculation of chk period | expand |
Hi Frank, On Sat, Nov 28, 2020 at 04:57:28PM +0000, Sean Young wrote: > Since commit 528222d853f9 ("media: rc: harmonize infrared durations to > microseconds"), the calculation of the chk period is wrong. As a result, > all reported IR will have incorrect timings. > > Now that the calculations are done in microseconds rather than nanoseconds, > we can fold the calculations in a simpler form with less rounding error. Would you be able to test this change please? That would be super-helpful. Thank you, Sean > > Cc: Frank Wunderlich <frank-w@public-files.de> > Fixes: 528222d853f9 ("media: rc: harmonize infrared durations to microseconds") > Signed-off-by: Sean Young <sean@mess.org> > --- > drivers/media/rc/mtk-cir.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/media/rc/mtk-cir.c b/drivers/media/rc/mtk-cir.c > index 5051a5e5244b..cdfb1eded306 100644 > --- a/drivers/media/rc/mtk-cir.c > +++ b/drivers/media/rc/mtk-cir.c > @@ -151,15 +151,12 @@ static inline u32 mtk_chk_period(struct mtk_ir *ir) > { > u32 val; > > - /* Period of raw software sampling in ns */ > - val = DIV_ROUND_CLOSEST(1000000000ul, > - clk_get_rate(ir->bus) / ir->data->div); > - > /* > * Period for software decoder used in the > * unit of raw software sampling > */ > - val = DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, val); > + val = DIV_ROUND_CLOSEST(MTK_IR_SAMPLE * clk_get_rate(ir->bus), > + USEC_PER_SEC * ir->data->div); > > dev_dbg(ir->dev, "@pwm clk = \t%lu\n", > clk_get_rate(ir->bus) / ir->data->div); > -- > 2.28.0
diff --git a/drivers/media/rc/mtk-cir.c b/drivers/media/rc/mtk-cir.c index 5051a5e5244b..cdfb1eded306 100644 --- a/drivers/media/rc/mtk-cir.c +++ b/drivers/media/rc/mtk-cir.c @@ -151,15 +151,12 @@ static inline u32 mtk_chk_period(struct mtk_ir *ir) { u32 val; - /* Period of raw software sampling in ns */ - val = DIV_ROUND_CLOSEST(1000000000ul, - clk_get_rate(ir->bus) / ir->data->div); - /* * Period for software decoder used in the * unit of raw software sampling */ - val = DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, val); + val = DIV_ROUND_CLOSEST(MTK_IR_SAMPLE * clk_get_rate(ir->bus), + USEC_PER_SEC * ir->data->div); dev_dbg(ir->dev, "@pwm clk = \t%lu\n", clk_get_rate(ir->bus) / ir->data->div);
Since commit 528222d853f9 ("media: rc: harmonize infrared durations to microseconds"), the calculation of the chk period is wrong. As a result, all reported IR will have incorrect timings. Now that the calculations are done in microseconds rather than nanoseconds, we can fold the calculations in a simpler form with less rounding error. Cc: Frank Wunderlich <frank-w@public-files.de> Fixes: 528222d853f9 ("media: rc: harmonize infrared durations to microseconds") Signed-off-by: Sean Young <sean@mess.org> --- drivers/media/rc/mtk-cir.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)