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| author | Cliff Cai <cliff.cai@analog.com> | 2010-01-28 20:44:18 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-03-02 14:54:48 -0800 |
| commit | 9f445cb29918dc488b7a9a92ef018599cce33df7 (patch) | |
| tree | 912365e85cc2b0f75dfc20a011c9d7e2db195362 /drivers/usb/musb/musb_gadget.c | |
| parent | 0ded2f146acfaf71e5f4c15b80cf89b3af48134c (diff) | |
| download | kernel_samsung_smdk4412-9f445cb29918dc488b7a9a92ef018599cce33df7.zip kernel_samsung_smdk4412-9f445cb29918dc488b7a9a92ef018599cce33df7.tar.gz kernel_samsung_smdk4412-9f445cb29918dc488b7a9a92ef018599cce33df7.tar.bz2 | |
USB: musb: disable double buffering for older RTL versions
Trying to use double buffer modes in RTL versions <2.0 may result in
infinite hangs or data corruption. So avoid them with older versions.
Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/musb/musb_gadget.c')
| -rw-r--r-- | drivers/usb/musb/musb_gadget.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index cbcf14a2..41de3a9 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -895,7 +895,14 @@ static int musb_gadget_enable(struct usb_ep *ep, /* REVISIT if can_bulk_split(), use by updating "tmp"; * likewise high bandwidth periodic tx */ - musb_writew(regs, MUSB_TXMAXP, tmp); + /* Set TXMAXP with the FIFO size of the endpoint + * to disable double buffering mode. Currently, It seems that double + * buffering has problem if musb RTL revision number < 2.0. + */ + if (musb->hwvers < MUSB_HWVERS_2000) + musb_writew(regs, MUSB_TXMAXP, hw_ep->max_packet_sz_tx); + else + musb_writew(regs, MUSB_TXMAXP, tmp); csr = MUSB_TXCSR_MODE | MUSB_TXCSR_CLRDATATOG; if (musb_readw(regs, MUSB_TXCSR) @@ -925,7 +932,13 @@ static int musb_gadget_enable(struct usb_ep *ep, /* REVISIT if can_bulk_combine() use by updating "tmp" * likewise high bandwidth periodic rx */ - musb_writew(regs, MUSB_RXMAXP, tmp); + /* Set RXMAXP with the FIFO size of the endpoint + * to disable double buffering mode. + */ + if (musb->hwvers < MUSB_HWVERS_2000) + musb_writew(regs, MUSB_RXMAXP, hw_ep->max_packet_sz_rx); + else + musb_writew(regs, MUSB_RXMAXP, tmp); /* force shared fifo to OUT-only mode */ if (hw_ep->is_shared_fifo) { |