| Message ID | 20170109163902.5268-5-abailon@baylibre.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
Hello! On 01/09/2017 07:39 PM, Alexandre Bailon wrote: > The dma may hung up if a teardown is initiated while an endpoint is still The DMA may hang up... > 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 <abailon@baylibre.com> [...] > 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); This is a horrible workaround, not even msleep()... [...] MBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 01/09/2017 07:34 PM, Sergei Shtylyov wrote: > Hello! > > On 01/09/2017 07:39 PM, Alexandre Bailon wrote: > >> The dma may hung up if a teardown is initiated while an endpoint is still > > The DMA may hang up... > >> 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 <abailon@baylibre.com> > [...] >> 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); > > This is a horrible workaround, not even msleep()... Indeed, that's a bad workaround but have not found a better one. cppi41_dma_channel_abort() is called from atomic context, so we can't use msleep(). And update the musb driver to call cppi41_dma_channel_abort() from process context would require too many changes. Best Regards, Alexandre > > [...] > > MBR, Sergei > -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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;
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 <abailon@baylibre.com> --- 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(-)