Hi, On Thu, Jan 19, 2023, Krishna Kurapati PSSNV wrote: > > > On 1/19/2023 6:06 AM, Thinh Nguyen wrote: > > Hi, > > > > On Sun, Jan 15, 2023, Krishna Kurapati wrote: > > > Currently the DWC3 driver supports only single port controller > > > which requires at most one HS and one SS PHY. > > > > Add note here that multi-port is for host mode for clarity. > > > > > > > > But the DWC3 USB controller can be connected to multiple ports and > > > each port can have their own PHYs. Each port of the multiport > > > controller can either be HS+SS capable or HS only capable > > > Proper quantification of them is required to modify GUSB2PHYCFG > > > and GUSB3PIPECTL registers appropriately. > > > > > > Add support for detecting, obtaining and configuring phy's supported > > > by a multiport controller and limit the max number of ports > > > supported to 4. > > > > > > Signed-off-by: Harsh Agarwal <quic_harshq@xxxxxxxxxxx> > > > Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx> > > > --- > > > drivers/usb/dwc3/core.c | 304 +++++++++++++++++++++++++++++----------- > > > drivers/usb/dwc3/core.h | 15 +- > > > drivers/usb/dwc3/drd.c | 14 +- > > > 3 files changed, 244 insertions(+), 89 deletions(-) > > > <snip> > > > @@ -1575,6 +1690,21 @@ static void dwc3_get_properties(struct dwc3 *dwc) > > > dwc->dis_split_quirk = device_property_read_bool(dev, > > > "snps,dis-split-quirk"); > > > + > > > + /* > > > + * If no mulitport properties are defined, default > > > > multi* > > > > > + * the port count to '1'. > > > + */ > > > > Can we initialize num_ports and num_ss_ports to 1 instead of setting it > > on error (similar to how we handle other properties). > > > Hi Thinh, > > Thanks for the review. On the bindings, Rob and Krzysztof have suggested > to get the num-ports and num-ss-ports by counting the Phy-names in DT. This may be a bit problematic for non-DT device. Currently pci devices pass fake DT properties to send these kinds of info. But that's fine, we can enhance dwc3 for non-DT devices later. > > Since there may be many cases where the user might skip giving any Phy's or > even skip different ports in the DT if he doesn't want to use them, can we > design/refactor the below logic as follows while mandating the fact that > user must give the SS Phy's if any starting from Port-0.: > > num-ss-ports = max_port_index (usb3-portX) + 1 > num-ports = max (max_port_index(usb2-portX), num-ss-ports) + 1 > > Ex: If there are 3 ports and only 1 is SS capable and user decides to skip > port-2 HS Phy. > > case-1: phy-names = "usb2-port0", "usb3-port0", "usb2-port-1" > case-2: phy-names = "usb2-port0", "usb2-port-1", "usb3-port1" > > In both cases, only one SS is present, just the order is changed. (Not sure > if last few ports can be made SS Capable instead of the first ports on any > HW) ? > > But according to the above formula: > > In case-1 : (num-ports = 2, num-ss-ports = 1) - This is correct > In case-2: (num-ports = 2, num-ss-ports = 2) - This is wrong > Can't we just walk through all the phy names to figure that out? Let's not require the user to specify Port-0 is SS capable if they can skip it. > I believe this covers all cases and I can read this in get_properties > function. Let me know your opinion if this design is good to proceed > further. > Thanks, Thinh
