From 098c1ef8fe6bcdfed7905cea1debdd3a0ff9a16f Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Thu, 28 Jan 2016 18:19:54 -0800 Subject: [PATCH] usb: dwc2: host: Set host_rx_fifo_size to 525 for rk3066 As documented in dwc2_calculate_dynamic_fifo(), host_rx_fifo_size should really be: 2 * ((Largest Packet size / 4) + 1 + 1) + n with n = number of host channel. We have 9 host channels, so 2 * ((1024/4) + 2) + 9 = 516 + 9 = 525 We've got 960 / 972 total_fifo_size on rk3288 (and presumably on rk3066) and 525 + 128 + 256 = 909 so we're still under on both ports even when we increment by 5. In the future, it would be nice if dwc2_calculate_dynamic_fifo() could handle the "too small" FIFO case and come up with something more dynamically. When we do that we can figure out how to allocate the extra 48 / 60 bytes of FIFO that we're currently wasting. NOTE: no known bugs are fixed by this patch, but it seems like a simple fix and ought to fix someone. Acked-by: John Youn Signed-off-by: Douglas Anderson Reviewed-by: Kever Yang Tested-by: Heiko Stuebner Signed-off-by: Felipe Balbi --- drivers/usb/dwc2/platform.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c index ecaa3d20e135..bc3f2a45a2bc 100644 --- a/drivers/usb/dwc2/platform.c +++ b/drivers/usb/dwc2/platform.c @@ -126,7 +126,7 @@ static const struct dwc2_core_params params_rk3066 = { .speed = -1, .enable_dynamic_fifo = 1, .en_multiple_tx_fifo = -1, - .host_rx_fifo_size = 520, /* 520 DWORDs */ + .host_rx_fifo_size = 525, /* 525 DWORDs */ .host_nperio_tx_fifo_size = 128, /* 128 DWORDs */ .host_perio_tx_fifo_size = 256, /* 256 DWORDs */ .max_transfer_size = -1, -- 2.39.5