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-rw-r--r--drivers/usb/musb/musb_host.c254
1 files changed, 140 insertions, 114 deletions
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index 79826eb47ba4..249951564b33 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -1661,6 +1661,122 @@ static int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
return done;
}
+
+/* Disadvantage of using mode 1:
+ * It's basically usable only for mass storage class; essentially all
+ * other protocols also terminate transfers on short packets.
+ *
+ * Details:
+ * An extra IN token is sent at the end of the transfer (due to AUTOREQ)
+ * If you try to use mode 1 for (transfer_buffer_length - 512), and try
+ * to use the extra IN token to grab the last packet using mode 0, then
+ * the problem is that you cannot be sure when the device will send the
+ * last packet and RxPktRdy set. Sometimes the packet is recd too soon
+ * such that it gets lost when RxCSR is re-set at the end of the mode 1
+ * transfer, while sometimes it is recd just a little late so that if you
+ * try to configure for mode 0 soon after the mode 1 transfer is
+ * completed, you will find rxcount 0. Okay, so you might think why not
+ * wait for an interrupt when the pkt is recd. Well, you won't get any!
+ */
+static int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
+ struct musb_hw_ep *hw_ep,
+ struct musb_qh *qh,
+ struct urb *urb,
+ size_t len,
+ u8 iso_err)
+{
+ struct musb *musb = hw_ep->musb;
+ void __iomem *epio = hw_ep->regs;
+ struct dma_channel *channel = hw_ep->rx_channel;
+ u16 rx_count, val;
+ int length, pipe, done;
+ dma_addr_t buf;
+
+ rx_count = musb_readw(epio, MUSB_RXCOUNT);
+ pipe = urb->pipe;
+
+ if (usb_pipeisoc(pipe)) {
+ int d_status = 0;
+ struct usb_iso_packet_descriptor *d;
+
+ d = urb->iso_frame_desc + qh->iso_idx;
+
+ if (iso_err) {
+ d_status = -EILSEQ;
+ urb->error_count++;
+ }
+ if (rx_count > d->length) {
+ if (d_status == 0) {
+ d_status = -EOVERFLOW;
+ urb->error_count++;
+ }
+ dev_dbg(musb->controller, "** OVERFLOW %d into %d\n",
+ rx_count, d->length);
+
+ length = d->length;
+ } else
+ length = rx_count;
+ d->status = d_status;
+ buf = urb->transfer_dma + d->offset;
+ } else {
+ length = rx_count;
+ buf = urb->transfer_dma + urb->actual_length;
+ }
+
+ channel->desired_mode = 0;
+#ifdef USE_MODE1
+ /* because of the issue below, mode 1 will
+ * only rarely behave with correct semantics.
+ */
+ if ((urb->transfer_flags & URB_SHORT_NOT_OK)
+ && (urb->transfer_buffer_length - urb->actual_length)
+ > qh->maxpacket)
+ channel->desired_mode = 1;
+ if (rx_count < hw_ep->max_packet_sz_rx) {
+ length = rx_count;
+ channel->desired_mode = 0;
+ } else {
+ length = urb->transfer_buffer_length;
+ }
+#endif
+
+ /* See comments above on disadvantages of using mode 1 */
+ val = musb_readw(epio, MUSB_RXCSR);
+ val &= ~MUSB_RXCSR_H_REQPKT;
+
+ if (channel->desired_mode == 0)
+ val &= ~MUSB_RXCSR_H_AUTOREQ;
+ else
+ val |= MUSB_RXCSR_H_AUTOREQ;
+ val |= MUSB_RXCSR_DMAENAB;
+
+ /* autoclear shouldn't be set in high bandwidth */
+ if (qh->hb_mult == 1)
+ val |= MUSB_RXCSR_AUTOCLEAR;
+
+ musb_writew(epio, MUSB_RXCSR, MUSB_RXCSR_H_WZC_BITS | val);
+
+ /* REVISIT if when actual_length != 0,
+ * transfer_buffer_length needs to be
+ * adjusted first...
+ */
+ done = dma->channel_program(channel, qh->maxpacket,
+ channel->desired_mode,
+ buf, length);
+
+ if (!done) {
+ dma->channel_release(channel);
+ hw_ep->rx_channel = NULL;
+ channel = NULL;
+ val = musb_readw(epio, MUSB_RXCSR);
+ val &= ~(MUSB_RXCSR_DMAENAB
+ | MUSB_RXCSR_H_AUTOREQ
+ | MUSB_RXCSR_AUTOCLEAR);
+ musb_writew(epio, MUSB_RXCSR, val);
+ }
+
+ return done;
+}
#else
static inline int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
struct musb_hw_ep *hw_ep,
@@ -1670,6 +1786,16 @@ static inline int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
{
return false;
}
+
+static inline int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
+ struct musb_hw_ep *hw_ep,
+ struct musb_qh *qh,
+ struct urb *urb,
+ size_t len,
+ u8 iso_err)
+{
+ return false;
+}
#endif
/*
@@ -1859,121 +1985,21 @@ void musb_host_rx(struct musb *musb, u8 epnum)
/* we are expecting IN packets */
if ((musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
musb_dma_cppi41(musb)) && dma) {
- struct dma_controller *c;
- u16 rx_count;
- int ret, length;
- dma_addr_t buf;
-
- rx_count = musb_readw(epio, MUSB_RXCOUNT);
-
- dev_dbg(musb->controller, "RX%d count %d, buffer 0x%llx len %d/%d\n",
- epnum, rx_count,
- (unsigned long long) urb->transfer_dma
- + urb->actual_length,
- qh->offset,
- urb->transfer_buffer_length);
-
- c = musb->dma_controller;
-
- if (usb_pipeisoc(pipe)) {
- int d_status = 0;
- struct usb_iso_packet_descriptor *d;
-
- d = urb->iso_frame_desc + qh->iso_idx;
-
- if (iso_err) {
- d_status = -EILSEQ;
- urb->error_count++;
- }
- if (rx_count > d->length) {
- if (d_status == 0) {
- d_status = -EOVERFLOW;
- urb->error_count++;
- }
- dev_dbg(musb->controller, "** OVERFLOW %d into %d\n",\
- rx_count, d->length);
-
- length = d->length;
- } else
- length = rx_count;
- d->status = d_status;
- buf = urb->transfer_dma + d->offset;
- } else {
- length = rx_count;
- buf = urb->transfer_dma +
- urb->actual_length;
- }
-
- dma->desired_mode = 0;
-#ifdef USE_MODE1
- /* because of the issue below, mode 1 will
- * only rarely behave with correct semantics.
- */
- if ((urb->transfer_flags &
- URB_SHORT_NOT_OK)
- && (urb->transfer_buffer_length -
- urb->actual_length)
- > qh->maxpacket)
- dma->desired_mode = 1;
- if (rx_count < hw_ep->max_packet_sz_rx) {
- length = rx_count;
- dma->desired_mode = 0;
- } else {
- length = urb->transfer_buffer_length;
- }
-#endif
-
-/* Disadvantage of using mode 1:
- * It's basically usable only for mass storage class; essentially all
- * other protocols also terminate transfers on short packets.
- *
- * Details:
- * An extra IN token is sent at the end of the transfer (due to AUTOREQ)
- * If you try to use mode 1 for (transfer_buffer_length - 512), and try
- * to use the extra IN token to grab the last packet using mode 0, then
- * the problem is that you cannot be sure when the device will send the
- * last packet and RxPktRdy set. Sometimes the packet is recd too soon
- * such that it gets lost when RxCSR is re-set at the end of the mode 1
- * transfer, while sometimes it is recd just a little late so that if you
- * try to configure for mode 0 soon after the mode 1 transfer is
- * completed, you will find rxcount 0. Okay, so you might think why not
- * wait for an interrupt when the pkt is recd. Well, you won't get any!
- */
-
- val = musb_readw(epio, MUSB_RXCSR);
- val &= ~MUSB_RXCSR_H_REQPKT;
-
- if (dma->desired_mode == 0)
- val &= ~MUSB_RXCSR_H_AUTOREQ;
+ dev_dbg(hw_ep->musb->controller,
+ "RX%d count %d, buffer 0x%llx len %d/%d\n",
+ epnum, musb_readw(epio, MUSB_RXCOUNT),
+ (unsigned long long) urb->transfer_dma
+ + urb->actual_length,
+ qh->offset,
+ urb->transfer_buffer_length);
+
+ done = musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh,
+ urb, xfer_len,
+ iso_err);
+ if (done)
+ goto finish;
else
- val |= MUSB_RXCSR_H_AUTOREQ;
- val |= MUSB_RXCSR_DMAENAB;
-
- /* autoclear shouldn't be set in high bandwidth */
- if (qh->hb_mult == 1)
- val |= MUSB_RXCSR_AUTOCLEAR;
-
- musb_writew(epio, MUSB_RXCSR,
- MUSB_RXCSR_H_WZC_BITS | val);
-
- /* REVISIT if when actual_length != 0,
- * transfer_buffer_length needs to be
- * adjusted first...
- */
- ret = c->channel_program(
- dma, qh->maxpacket,
- dma->desired_mode, buf, length);
-
- if (!ret) {
- c->channel_release(dma);
- hw_ep->rx_channel = NULL;
- dma = NULL;
- val = musb_readw(epio, MUSB_RXCSR);
- val &= ~(MUSB_RXCSR_DMAENAB
- | MUSB_RXCSR_H_AUTOREQ
- | MUSB_RXCSR_AUTOCLEAR);
- musb_writew(epio, MUSB_RXCSR, val);
- }
+ dev_err(musb->controller, "error: rx_dma failed\n");
}
if (!dma) {