On Mon, Nov 30, 2020 at 06:24:40AM +0000, Peter Chen wrote:
On 20-11-27 15:05:55, Greg Kroah-Hartman wrote:
From: Will McVicker willmcvicker@google.com
Align the SuperSpeed Plus bitrate for f_rndis to match f_ncm's ncm_bitrate defined by commit 1650113888fe ("usb: gadget: f_ncm: add SuperSpeed descriptors for CDC NCM").
Cc: Felipe Balbi balbi@kernel.org Cc: EJ Hsu ejh@nvidia.com Cc: Peter Chen peter.chen@nxp.com Cc: stable stable@vger.kernel.org Signed-off-by: Will McVicker willmcvicker@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
drivers/usb/gadget/function/f_rndis.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c index 9534c8ab62a8..0739b05a0ef7 100644 --- a/drivers/usb/gadget/function/f_rndis.c +++ b/drivers/usb/gadget/function/f_rndis.c @@ -87,8 +87,10 @@ static inline struct f_rndis *func_to_rndis(struct usb_function *f) /* peak (theoretical) bulk transfer rate in bits-per-second */ static unsigned int bitrate(struct usb_gadget *g) {
- if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
return 4250000000U;
Is tested value or spec defined value?
if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
return 13 * 1024 * 8 * 1000 * 8;
return 3750000000U;
13 * 1024 * 8 * 1000 * 8 = 851,968,000, how 3750000000U is calculated?
else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH) return 13 * 512 * 8 * 1000 * 8; else -- 2.29.2
--
Thanks, Peter Chen
Hi Peter,
Thanks for the reviews! Regarding the updated transfer rates, please refer to the f_ncm commit email thread by Lorenzo that explains the reasoning behind these speeds:
https://patchwork.kernel.org/project/linux-usb/patch/20200818165848.4117493-...
Thanks, Will