[PATCH 4.19 38/58] usb: gadget: aspeed: fix stop dma register setting.

Greg Kroah-Hartman
2021-01-26T08:32:55Z

From: Ryan Chen <ryan_chen@aspeedtech.com>

commit 4e0dcf62ab4cf917d0cbe751b8bf229a065248d4 upstream.

The vhub engine has two dma mode, one is descriptor list, another
is single stage DMA. Each mode has different stop register setting.
Descriptor list operation (bit2) : 0 disable reset, 1: enable reset
Single mode operation (bit0) : 0 : disable, 1: enable

Fixes: 7ecca2a4080c ("usb/gadget: Add driver for Aspeed SoC virtual hub")
Cc: stable <stable@vger.kernel.org>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Link: https://lore.kernel.org/r/20210108081238.10199-2-ryan_chen@aspeedtech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/gadget/udc/aspeed-vhub/epn.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
@@ -420,7 +420,10 @@ static void ast_vhub_stop_active_req(str
u32 state, reg, loops;

/* Stop DMA activity */
- writel(0, ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
+ if (ep->epn.desc_mode)
+ writel(VHUB_EP_DMA_CTRL_RESET, ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);
+ else
+ writel(0, ep->epn.regs + AST_VHUB_EP_DMA_CTLSTAT);

/* Wait for it to complete */
for (loops = 0; loops < 1000; loops++) {