[PATCH 4.14 059/237] usb: dwc2: Fix IN FIFO allocation

Greg Kroah-Hartman
2020-02-27T14:39:38Z

From: John Keeping <john@metanate.com>

[ Upstream commit 644139f8b64d818f6345351455f14471510879a5 ]

On chips with fewer FIFOs than endpoints (for example RK3288 which has 9
endpoints, but only 6 which are cabable of input), the DPTXFSIZN
registers above the FIFO count may return invalid values.

With logging added on startup, I see:

dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=1 sz=256
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=2 sz=128
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=3 sz=128
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=4 sz=64
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=5 sz=64
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=6 sz=32
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=7 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=8 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=9 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=10 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=11 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=12 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=13 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=14 sz=0
dwc2 ff580000.usb: dwc2_hsotg_init_fifo: ep=15 sz=0

but:

# cat /sys/kernel/debug/ff580000.usb/fifo
Non-periodic FIFOs:
RXFIFO: Size 275
NPTXFIFO: Size 16, Start 0x00000113

Periodic TXFIFOs:
DPTXFIFO 1: Size 256, Start 0x00000123
DPTXFIFO 2: Size 128, Start 0x00000223
DPTXFIFO 3: Size 128, Start 0x000002a3
DPTXFIFO 4: Size 64, Start 0x00000323
DPTXFIFO 5: Size 64, Start 0x00000363
DPTXFIFO 6: Size 32, Start 0x000003a3
DPTXFIFO 7: Size 0, Start 0x000003e3
DPTXFIFO 8: Size 0, Start 0x000003a3
DPTXFIFO 9: Size 256, Start 0x00000123

so it seems that FIFO 9 is mirroring FIFO 1.

Fix the allocation by using the FIFO count instead of the endpoint count
when selecting a FIFO for an endpoint.

Acked-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/dwc2/gadget.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 4af9a1c652edb..aeb6f7c84ea0a 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3933,11 +3933,12 @@ static int dwc2_hsotg_ep_enable(struct usb_ep *ep,
* a unique tx-fifo even if it is non-periodic.
*/
if (dir_in && hsotg->dedicated_fifos) {
+ unsigned fifo_count = dwc2_hsotg_tx_fifo_count(hsotg);
u32 fifo_index = 0;
u32 fifo_size = UINT_MAX;

size = hs_ep->ep.maxpacket * hs_ep->mc;
- for (i = 1; i < hsotg->num_of_eps; ++i) {
+ for (i = 1; i <= fifo_count; ++i) {
if (hsotg->fifo_map & (1 << i))
continue;
val = dwc2_readl(hsotg->regs + DPTXFSIZN(i));
--
2.20.1