Hi Jiri,
> -----Original Message-----
> From: Jiri Slaby [mailto:jsl...@suse.cz]
> Sent: Wednesday, October 28, 2015 8:54 AM
> To: sta...@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org; Liu, Bin; Balbi, Felipe; Oliver Neukum; Jiri
> Slaby
> Subject: [PATCH 3.12 105/123] usb: musb: cppi41: improve rx channel abort
> routine
>
> From: Bin Liu <b-...@ti.com>
>
> 3.12-stable review patch. If anyone has any objections, please let me know.
It seems this backport missing the dependency 0149b07 upstream (usb: musb:
cppi41: correct the macro name EP_MODE_AUTOREG_*), which causes the micro
name mismatch.
Sorry for the late response, I just received the regression report.
Thanks,
-Bin.
>
> ===============
>
> commit cb83df77f3ec151d68a1b6be957207e6fc7b7f50 upstream.
>
> 1. set AUTOREQ to NONE at the beginning of teardown;
>
> 2. add delay for dma pipeline to drain;
>
> 3. Do not set USB_TDOWN bit for RX teardown.
>
> The CPPI hw has an issue that when tearing down a RX channel, if
> another RX channel is receiving data, the CPPI will lockup.
>
> To workaround the issue, do not set the CPPI TD bit. The steps before
> this point ensures the CPPI channel will be torn down properly.
>
> Signed-off-by: Bin Liu <b-...@ti.com>
> Signed-off-by: Felipe Balbi <ba...@ti.com>
> Cc: Oliver Neukum <oneu...@suse.com>
> Signed-off-by: Jiri Slaby <jsl...@suse.cz>
> ---
> drivers/usb/musb/musb_cppi41.c | 12 +++++++++---
> 1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/musb/musb_cppi41.c
> b/drivers/usb/musb/musb_cppi41.c index 77b475a43dad..1c9c626248fd 100644
> --- a/drivers/usb/musb/musb_cppi41.c
> +++ b/drivers/usb/musb/musb_cppi41.c
> @@ -507,10 +507,15 @@ static int cppi41_dma_channel_abort(struct
> dma_channel *channel)
> csr &= ~MUSB_TXCSR_DMAENAB;
> musb_writew(epio, MUSB_TXCSR, csr);
> } else {
> + cppi41_set_autoreq_mode(cppi41_channel,
> EP_MODE_AUTOREQ_NONE);
> +
> csr = musb_readw(epio, MUSB_RXCSR);
> csr &= ~(MUSB_RXCSR_H_REQPKT | MUSB_RXCSR_DMAENAB);
> musb_writew(epio, MUSB_RXCSR, csr);
>
> + /* wait to drain cppi dma pipe line */
> + udelay(50);
> +
> csr = musb_readw(epio, MUSB_RXCSR);
> if (csr & MUSB_RXCSR_RXPKTRDY) {
> csr |= MUSB_RXCSR_FLUSHFIFO;
> @@ -524,13 +529,14 @@ static int cppi41_dma_channel_abort(struct
> dma_channel *channel)
> tdbit <<= 16;
>
> do {
> - musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
> + if (is_tx)
> + musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
> ret = dmaengine_terminate_all(cppi41_channel->dc);
> } while (ret == -EAGAIN);
>
> - musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
> -
> if (is_tx) {
> + musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
> +
> csr = musb_readw(epio, MUSB_TXCSR);
> if (csr & MUSB_TXCSR_TXPKTRDY) {
> csr |= MUSB_TXCSR_FLUSHFIFO;
> --
> 2.6.2
