From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Bailon Subject: [PATCH 4/4] usb: musb: musb_cppi41: Workaround dma stall issue during teardown Date: Mon, 9 Jan 2017 17:39:02 +0100 Message-ID: <20170109163902.5268-5-abailon@baylibre.com> References: <20170109163902.5268-1-abailon@baylibre.com> Return-path: In-Reply-To: <20170109163902.5268-1-abailon-rdvid1DuHRBWk0Htik3J/w@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: b-liu-l0cyMroinI0@public.gmane.org Cc: vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, nsekhar-l0cyMroinI0@public.gmane.org, khilman-rdvid1DuHRBWk0Htik3J/w@public.gmane.org, ptitiano-rdvid1DuHRBWk0Htik3J/w@public.gmane.org, tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, david-nq/r/kbU++upp/zk7JDF2g@public.gmane.org, Alexandre Bailon List-Id: devicetree@vger.kernel.org The dma may hung 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 --- 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 74dcc07..3513284 100644 --- a/drivers/usb/musb/da8xx.c +++ b/drivers/usb/musb/da8xx.c @@ -458,7 +458,7 @@ static inline u8 get_vbus_power(struct device *dev) } static const struct musb_platform_ops da8xx_ops = { - .quirks = MUSB_DMA_CPPI41 | MUSB_INDEXED_EP, + .quirks = MUSB_DMA_CPPI41 | MUSB_INDEXED_EP | 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 ade902e..d129278 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(7) #define MUSB_DMA_UX500 BIT(6) #define MUSB_DMA_CPPI41 BIT(5) #define MUSB_DMA_CPPI BIT(4) diff --git a/drivers/usb/musb/musb_cppi41.c b/drivers/usb/musb/musb_cppi41.c index 1636385..8fdbc17 100644 --- a/drivers/usb/musb/musb_cppi41.c +++ b/drivers/usb/musb/musb_cppi41.c @@ -547,6 +547,10 @@ 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; -- 2.10.2 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html