On 2/6/2015 2:23 PM, John Youn wrote: > On 2/6/2015 6:02 AM, Zhangfei Gao wrote: >> On 6 February 2015 at 16:07, Kaukab, Yousaf <yousaf.kaukab@xxxxxxxxx> wrote: >>>>>> GAHBCFG_HBSTLEN_INCR4 << diff --git a/drivers/usb/dwc2/gadget.c >>>>>> b/drivers/usb/dwc2/gadget.c index 15aa578..20085de 100644 >>>>>> --- a/drivers/usb/dwc2/gadget.c >>>>>> +++ b/drivers/usb/dwc2/gadget.c >>>>>> @@ -2314,9 +2314,13 @@ void s3c_hsotg_core_init_disconnected(struct >>>>>> dwc2_hsotg *hsotg, >>>>>> GINTSTS_USBSUSP | GINTSTS_WKUPINT, >>>>>> hsotg->regs + GINTMSK); >>>>>> >>>>>> + if ((hsotg->core_params) && (hsotg->core_params->ahbcfg != - >>>>>> 1)) >>>>>> + val = hsotg->core_params->ahbcfg & >>>>>> ~GAHBCFG_CTRL_MASK; >>>>>> + else >>>>>> + val = GAHBCFG_HBSTLEN_INCR4 << >>>>>> GAHBCFG_HBSTLEN_SHIFT; >>>>>> + >>>>>> if (using_dma(hsotg)) >>>>>> - writel(GAHBCFG_GLBL_INTR_EN | >>>>>> GAHBCFG_DMA_EN | >>>>>> - (GAHBCFG_HBSTLEN_INCR4 << >>>>>> GAHBCFG_HBSTLEN_SHIFT), >>>>>> + writel(GAHBCFG_GLBL_INTR_EN | >>>>>> GAHBCFG_DMA_EN | val, >>>>>> hsotg->regs + GAHBCFG); >>>>>> else >>>>>> writel(((hsotg->dedicated_fifos) ? >>>>>> (GAHBCFG_NP_TXF_EMP_LVL | >>>>> >>>>> There are other bits in GAHBCFG that can be set from platform. They will be >>>> preserved by your patch, as they are not part of GAHBCFG_CTRL_MASK, but >>>> only in case dma is enabled. Perhaps preserve them in non-dma case as well. >>>> >>>> Here may have issue if also set hsotg->core_params->ahbcfg for non-dma case, >>>> since GAHBCFG[4:1] may be set. >>> >>> You can mask off HBstLen in that case. However, I don't think setting burst length will be an issue in non DMA case as DWC2 will not act as a bus master. John, can you please confirm if setting burst length will be an issue in non-dma case? > > I don't think it hurts to preserve those bits, but I will check. > I can confirm that AHB_SINGLE, NOTI_ALL_DMA_WRIT, REM_MEM_SUPP, HBSTLEN, and INV_DESC_ENDIANNESS only apply in DMA mode and are ignored in slave mode operation. John -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
