From 593bc4622a98c172dbb939103aef917d1800a663 Mon Sep 17 00:00:00 2001 From: Alexandre Bailon Date: Sun, 16 Apr 2017 23:21:18 -0500 Subject: [PATCH] usb: musb: musb_cppi41: Workaround DMA stall issue during teardown The DMA may hang up if a teardown is initiated while an endpoint is still active (Advisory 2.3.27 of DA8xx errata). To workaround this issue, add a delay before to initiate the teardown. Signed-off-by: Alexandre Bailon Signed-off-by: Bin Liu Signed-off-by: Greg Kroah-Hartman --- drivers/usb/musb/da8xx.c | 2 +- drivers/usb/musb/musb_core.h | 1 + drivers/usb/musb/musb_cppi41.c | 4 ++++ 3 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/usb/musb/da8xx.c b/drivers/usb/musb/da8xx.c index 7b9a44dc1188..5a8a031485ea 100644 --- a/drivers/usb/musb/da8xx.c +++ b/drivers/usb/musb/da8xx.c @@ -483,7 +483,7 @@ da8xx_dma_controller_create(struct musb *musb, void __iomem *base) static const struct musb_platform_ops da8xx_ops = { .quirks = MUSB_INDEXED_EP | MUSB_PRESERVE_SESSION | - MUSB_DMA_CPPI41, + MUSB_DMA_CPPI41 | MUSB_DA8XX, .init = da8xx_musb_init, .exit = da8xx_musb_exit, diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h index 5b708be6d1d1..3e98d4268a64 100644 --- a/drivers/usb/musb/musb_core.h +++ b/drivers/usb/musb/musb_core.h @@ -172,6 +172,7 @@ struct musb_io; */ struct musb_platform_ops { +#define MUSB_DA8XX BIT(8) #define MUSB_PRESERVE_SESSION BIT(7) #define MUSB_DMA_UX500 BIT(6) #define MUSB_DMA_CPPI41 BIT(5) diff --git a/drivers/usb/musb/musb_cppi41.c b/drivers/usb/musb/musb_cppi41.c index 355655f8a3fb..e7c8b1b8bf22 100644 --- a/drivers/usb/musb/musb_cppi41.c +++ b/drivers/usb/musb/musb_cppi41.c @@ -571,6 +571,10 @@ static int cppi41_dma_channel_abort(struct dma_channel *channel) } } + /* DA8xx Advisory 2.3.27: wait 250 ms before to start the teardown */ + if (musb->io.quirks & MUSB_DA8XX) + mdelay(250); + tdbit = 1 << cppi41_channel->port_num; if (is_tx) tdbit <<= 16; -- 2.39.5