Re: [PATCH] usb: dwc2: gadget: Fix GUSBCFG.USBTRDTIM value

From: Amelie DELAUNAY
Date: Thu Jan 12 2017 - 10:41:42 EST


Hi all,
Sorry, I did not see Pengcheng Li patch which is exactly the same:
https://patchwork.kernel.org/patch/9347979/

Regards

On 01/12/2017 04:36 PM, Amelie Delaunay wrote:
USBTrdTim must be programmed to 0x5 when phy has a UTMI+ 16-bit wide
interface or 0x9 when it has a 8-bit wide interface.
GUSBCFG reset value (Value After Reset: 0x1400) sets USBTrdTim to 0x5.
In case of 8-bit UTMI+, without clearing GUSBCFG.USBTRDTIM mask, USBTrdTim
results in 0xD (0x5 | 0x9).
That's why we need to clear GUSBCFG.USBTRDTIM mask before setting USBTrdTim
value, to ensure USBTrdTim is correctly set in case of 8-bit UTMI+.

Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
---
drivers/usb/dwc2/gadget.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index c55db4a..86b2076 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3169,7 +3169,7 @@ void dwc2_hsotg_core_init_disconnected(struct dwc2_hsotg *hsotg,
/* keep other bits untouched (so e.g. forced modes are not lost) */
usbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
usbcfg &= ~(GUSBCFG_TOUTCAL_MASK | GUSBCFG_PHYIF16 | GUSBCFG_SRPCAP |
- GUSBCFG_HNPCAP);
+ GUSBCFG_HNPCAP | GUSBCFG_USBTRDTIM_MASK);

if (hsotg->params.phy_type == DWC2_PHY_TYPE_PARAM_FS &&
(hsotg->params.speed == DWC2_SPEED_PARAM_FULL ||
@@ -4131,7 +4131,7 @@ static void dwc2_hsotg_init(struct dwc2_hsotg *hsotg)
/* keep other bits untouched (so e.g. forced modes are not lost) */
usbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
usbcfg &= ~(GUSBCFG_TOUTCAL_MASK | GUSBCFG_PHYIF16 | GUSBCFG_SRPCAP |
- GUSBCFG_HNPCAP);
+ GUSBCFG_HNPCAP | GUSBCFG_USBTRDTIM_MASK);

/* set the PLL on, remove the HNP/SRP and set the PHY */
trdtim = (hsotg->phyif == GUSBCFG_PHYIF8) ? 9 : 5;