diff options
author | Felipe Balbi <balbi@ti.com> | 2013-12-30 12:33:53 -0600 |
---|---|---|
committer | Felipe Balbi <balbi@ti.com> | 2015-03-09 10:38:48 -0500 |
commit | e3c93e1a3f35be4cf1493d3ccfb0c6d9209e4922 (patch) | |
tree | c75b4cfcfd7bff9f14189e1932959ab655f8ca3e /drivers/usb/musb | |
parent | d5638fcf15bc65584877f00d4b0094cc4a66ad4e (diff) | |
download | op-kernel-dev-e3c93e1a3f35be4cf1493d3ccfb0c6d9209e4922.zip op-kernel-dev-e3c93e1a3f35be4cf1493d3ccfb0c6d9209e4922.tar.gz |
usb: musb: core: fix TX/RX endpoint order
As per Mentor Graphics' documentation, we should
always handle TX endpoints before RX endpoints.
This patch fixes that error while also updating
some hard-to-read comments which were scattered
around musb_interrupt().
This patch should be backported as far back as
possible since this error has been in the driver
since it's conception.
Cc: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Diffstat (limited to 'drivers/usb/musb')
-rw-r--r-- | drivers/usb/musb/musb_core.c | 44 |
1 files changed, 26 insertions, 18 deletions
diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 067920f..461bfe8 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -1597,16 +1597,30 @@ irqreturn_t musb_interrupt(struct musb *musb) is_host_active(musb) ? "host" : "peripheral", musb->int_usb, musb->int_tx, musb->int_rx); - /* the core can interrupt us for multiple reasons; docs have - * a generic interrupt flowchart to follow + /** + * According to Mentor Graphics' documentation, flowchart on page 98, + * IRQ should be handled as follows: + * + * . Resume IRQ + * . Session Request IRQ + * . VBUS Error IRQ + * . Suspend IRQ + * . Connect IRQ + * . Disconnect IRQ + * . Reset/Babble IRQ + * . SOF IRQ (we're not using this one) + * . Endpoint 0 IRQ + * . TX Endpoints + * . RX Endpoints + * + * We will be following that flowchart in order to avoid any problems + * that might arise with internal Finite State Machine. */ + if (musb->int_usb) retval |= musb_stage0_irq(musb, musb->int_usb, devctl); - /* "stage 1" is handling endpoint irqs */ - - /* handle endpoint 0 first */ if (musb->int_tx & 1) { if (is_host_active(musb)) retval |= musb_h_ep0_irq(musb); @@ -1614,37 +1628,31 @@ irqreturn_t musb_interrupt(struct musb *musb) retval |= musb_g_ep0_irq(musb); } - /* RX on endpoints 1-15 */ - reg = musb->int_rx >> 1; + reg = musb->int_tx >> 1; ep_num = 1; while (reg) { if (reg & 1) { - /* musb_ep_select(musb->mregs, ep_num); */ - /* REVISIT just retval = ep->rx_irq(...) */ retval = IRQ_HANDLED; if (is_host_active(musb)) - musb_host_rx(musb, ep_num); + musb_host_tx(musb, ep_num); else - musb_g_rx(musb, ep_num); + musb_g_tx(musb, ep_num); } - reg >>= 1; ep_num++; } - /* TX on endpoints 1-15 */ - reg = musb->int_tx >> 1; + reg = musb->int_rx >> 1; ep_num = 1; while (reg) { if (reg & 1) { - /* musb_ep_select(musb->mregs, ep_num); */ - /* REVISIT just retval |= ep->tx_irq(...) */ retval = IRQ_HANDLED; if (is_host_active(musb)) - musb_host_tx(musb, ep_num); + musb_host_rx(musb, ep_num); else - musb_g_tx(musb, ep_num); + musb_g_rx(musb, ep_num); } + reg >>= 1; ep_num++; } |