Hi Josh, On Tue, 25 Nov 2014, Josh Wu wrote: > The burst length could be BEATS_4/8/16. Before this patch, isi use default > value BEATS_4. To imporve the performance we could set it to BEATS_16. > > Otherwise sometime it would cause the ISI overflow error. Without looking at datasheets - what does this bit do? Change the transfer length? What happens then if the data amount isn't a multiple of the transfer size? Thanks Guennadi > > Reported-by: Bo Shen <voice.shen@xxxxxxxxx> > Signed-off-by: Josh Wu <josh.wu@xxxxxxxxx> > --- > drivers/media/platform/soc_camera/atmel-isi.c | 2 ++ > include/media/atmel-isi.h | 4 ++++ > 2 files changed, 6 insertions(+) > > diff --git a/drivers/media/platform/soc_camera/atmel-isi.c b/drivers/media/platform/soc_camera/atmel-isi.c > index ee5650f..fda587b 100644 > --- a/drivers/media/platform/soc_camera/atmel-isi.c > +++ b/drivers/media/platform/soc_camera/atmel-isi.c > @@ -839,6 +839,8 @@ static int isi_camera_set_bus_param(struct soc_camera_device *icd) > if (isi->pdata.full_mode) > cfg1 |= ISI_CFG1_FULL_MODE; > > + cfg1 |= ISI_CFG1_THMASK_BEATS_16; > + > isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS); > isi_writel(isi, ISI_CFG1, cfg1); > > diff --git a/include/media/atmel-isi.h b/include/media/atmel-isi.h > index c2e5703..6008b09 100644 > --- a/include/media/atmel-isi.h > +++ b/include/media/atmel-isi.h > @@ -59,6 +59,10 @@ > #define ISI_CFG1_FRATE_DIV_MASK (7 << 8) > #define ISI_CFG1_DISCR (1 << 11) > #define ISI_CFG1_FULL_MODE (1 << 12) > +/* Definition for THMASK(ISI_V2) */ > +#define ISI_CFG1_THMASK_BEATS_4 (0 << 13) > +#define ISI_CFG1_THMASK_BEATS_8 (1 << 13) > +#define ISI_CFG1_THMASK_BEATS_16 (2 << 13) > > /* Bitfields in CFG2 */ > #define ISI_CFG2_GRAYSCALE (1 << 13) > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
