musb_hdrc: musb procfs updates

Tighten up error handling in the procfs dump, and avoid returning
bogus values from the read() system call.  Report single vs double
buffering for FIFO setup.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

diff --git a/drivers/usb/musb/musb_procfs.c b/drivers/usb/musb/musb_procfs.c
index 02eabe750d2543b6cdfe521dec2d16b94a5af62c..c3fa527a7de70b9411a7af6925eb6ade6e457db0 100644 (file)
--- a/drivers/usb/musb/musb_procfs.c
+++ b/drivers/usb/musb/musb_procfs.c
@@ -91,6 +91,8 @@ static int dump_qh(struct musb_qh *qh, char *buf, unsigned max)
                                s = "iso"; break;
                        }; s; }),
                        qh->maxpacket);
+       if (count <= 0)
+               return 0;
        buf += count;
        max -= count;
 
@@ -99,7 +101,7 @@ static int dump_qh(struct musb_qh *qh, char *buf, unsigned max)
                                usb_pipein(urb->pipe) ? "in" : "out",
                                urb, urb->actual_length,
                                urb->transfer_buffer_length);
-               if (tmp < 0)
+               if (tmp <= 0)
                        break;
                tmp = min(tmp, (int)max);
                count += tmp;
@@ -119,7 +121,7 @@ dump_queue(struct list_head *q, char *buf, unsigned max)
                int     tmp;
 
                tmp = dump_qh(qh, buf, max);
-               if (tmp < 0)
+               if (tmp <= 0)
                        break;
                tmp = min(tmp, (int)max);
                count += tmp;
@@ -137,14 +139,23 @@ static int dump_ep(struct musb_ep *ep, char *buffer, unsigned max)
        char            *buf = buffer;
        int             code = 0;
        void __iomem    *regs = ep->hw_ep->regs;
+       char            *mode = "1buf";
+
+       if (ep->is_in) {
+               if (ep->hw_ep->tx_double_buffered)
+                       mode = "2buf";
+       } else {
+               if (ep->hw_ep->rx_double_buffered)
+                       mode = "2buf";
+       }
 
        do {
                struct usb_request      *req;
 
                code = snprintf(buf, max,
-                               "\n%s (hw%d): %scsr %04x maxp %04x\n",
+                               "\n%s (hw%d): %s%s, csr %04x maxp %04x\n",
                                ep->name, ep->bEndNumber,
-                               ep->dma ? "dma, " : "",
+                               mode, ep->dma ? " dma" : "",
                                musb_readw(regs,
                                        (ep->is_in || !ep->bEndNumber)
                                                ? MGC_O_HDRC_TXCSR
@@ -153,7 +164,7 @@ static int dump_ep(struct musb_ep *ep, char *buffer, unsigned max)
                                                ? MGC_O_HDRC_TXMAXP
                                                : MGC_O_HDRC_RXMAXP)
                                );
-               if (code < 0)
+               if (code <= 0)
                        break;
                code = min(code, (int) max);
                buf += code;
@@ -189,7 +200,7 @@ static int dump_ep(struct musb_ep *ep, char *buffer, unsigned max)
                                musb_readl(ram, 5 * 4),
                                musb_readl(ram, 6 * 4),
                                musb_readl(ram, 7 * 4));
-                       if (code < 0)
+                       if (code <= 0)
                                break;
                        code = min(code, (int) max);
                        buf += code;
@@ -198,7 +209,7 @@ static int dump_ep(struct musb_ep *ep, char *buffer, unsigned max)
 
                if (list_empty(&ep->req_list)) {
                        code = snprintf(buf, max, "\t(queue empty)\n");
-                       if (code < 0)
+                       if (code <= 0)
                                break;
                        code = min(code, (int) max);
                        buf += code;
@@ -211,14 +222,14 @@ static int dump_ep(struct musb_ep *ep, char *buffer, unsigned max)
                                        req->zero ? "zero, " : "",
                                        req->short_not_ok ? "!short, " : "",
                                        req->actual, req->length);
-                       if (code < 0)
+                       if (code <= 0)
                                break;
                        code = min(code, (int) max);
                        buf += code;
                        max -= code;
                }
        } while(0);
-       return (buf > buffer) ? (buf - buffer) : code;
+       return buf - buffer;
 }
 #endif
 
@@ -260,17 +271,15 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                        /* END TEMPORARY */
 
 
-                       /* FIXME for rx and tx dump hardware fifo and
-                        * double-buffer flags ... and make register and stat
-                        * dumps (mostly) usable on the peripheral side too
-                        */
                        if (dump_rx) {
                                code = snprintf(buf, max,
-                                       "\nRX%d:  rxcsr %04x interval %02x "
+                                       "\nRX%d: %s rxcsr %04x interval %02x "
                                        "max %04x type %02x; "
                                        "dev %d hub %d port %d"
                                        "\n",
                                        bEnd,
+                                       pEnd->rx_double_buffered
+                                               ? "2buf" : "1buf",
                                        musb_readw(regs, MGC_O_HDRC_RXCSR),
                                        musb_readb(regs, MGC_O_HDRC_RXINTERVAL),
                                        musb_readw(regs, MGC_O_HDRC_RXMAXP),
@@ -286,7 +295,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                MGC_BUSCTL_OFFSET(bEnd,
                                                MGC_O_HDRC_RXHUBPORT))
                                        );
-                               if (code < 0)
+                               if (code <= 0)
                                        break;
                                code = min(code, (int) max);
                                buf += code;
@@ -322,7 +331,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                musb_readl(ram, 5 * 4),
                                                musb_readl(ram, 6 * 4),
                                                musb_readl(ram, 7 * 4));
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -334,7 +343,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                        &pThis->in_bulk)) {
                                        code = dump_queue(&pThis->in_bulk,
                                                        buf, max);
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -342,7 +351,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                } else if (pThis->periodic[bEnd]) {
                                        code = dump_qh(pThis->periodic[bEnd],
                                                        buf, max);
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -352,11 +361,13 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
 
                        if (dump_tx) {
                                code = snprintf(buf, max,
-                                       "\nTX%d:  txcsr %04x interval %02x "
+                                       "\nTX%d: %s txcsr %04x interval %02x "
                                        "max %04x type %02x; "
                                        "dev %d hub %d port %d"
                                        "\n",
                                        bEnd,
+                                       pEnd->tx_double_buffered
+                                               ? "2buf" : "1buf",
                                        musb_readw(regs, MGC_O_HDRC_TXCSR),
                                        musb_readb(regs, MGC_O_HDRC_TXINTERVAL),
                                        musb_readw(regs, MGC_O_HDRC_TXMAXP),
@@ -372,7 +383,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                MGC_BUSCTL_OFFSET(bEnd,
                                                MGC_O_HDRC_TXHUBPORT))
                                        );
-                               if (code < 0)
+                               if (code <= 0)
                                        break;
                                code = min(code, (int) max);
                                buf += code;
@@ -401,7 +412,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                musb_readl(ram, 5 * 4),
                                                musb_readl(ram, 6 * 4),
                                                musb_readl(ram, 7 * 4));
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -413,7 +424,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                        &pThis->control)) {
                                        code = dump_queue(&pThis->control,
                                                        buf, max);
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -423,7 +434,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                                        &pThis->out_bulk)) {
                                        code = dump_queue(&pThis->out_bulk,
                                                        buf, max);
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -431,7 +442,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                                } else if (pThis->periodic[bEnd]) {
                                        code = dump_qh(pThis->periodic[bEnd],
                                                        buf, max);
-                                       if (code < 0)
+                                       if (code <= 0)
                                                break;
                                        code = min(code, (int) max);
                                        buf += code;
@@ -446,7 +457,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
 
                        if (pEnd->ep_in.desc || !bEnd) {
                                code = dump_ep(&pEnd->ep_in, buf, max);
-                               if (code < 0)
+                               if (code <= 0)
                                        break;
                                code = min(code, (int) max);
                                buf += code;
@@ -454,7 +465,7 @@ dump_end_info(struct musb *pThis, u8 bEnd, char *aBuffer, unsigned max)
                        }
                        if (pEnd->ep_out.desc) {
                                code = dump_ep(&pEnd->ep_out, buf, max);
-                               if (code < 0)
+                               if (code <= 0)
                                        break;
                                code = min(code, (int) max);
                                buf += code;
@@ -483,15 +494,15 @@ static int dump_header_stats(struct musb *pThis, char *buffer)
                        (pThis->bIsMultipoint ? "M" : ""), MUSB_MODE(pThis),
                        musb_readb(pBase, MGC_O_HDRC_POWER),
                        musb_readb(pBase, MGC_O_HDRC_DEVCTL));
-       if (count < 0)
-               return count;
+       if (count <= 0)
+               return 0;
        buffer += count;
 
        code = sprintf(buffer, "OTG state: %s; %sactive\n",
                        otg_state_string(pThis),
                        pThis->is_active ? "" : "in");
-       if (code < 0)
-               return code;
+       if (code <= 0)
+               goto done;
        buffer += code;
        count += code;
 
@@ -519,8 +530,8 @@ static int dump_header_stats(struct musb *pThis, char *buffer)
                        ", debug=%d [eps=%d]\n",
                debug,
                pThis->bEndCount);
-       if (code < 0)
-               return code;
+       if (code <= 0)
+               goto done;
        count += code;
        buffer += code;
 
@@ -538,8 +549,8 @@ static int dump_header_stats(struct musb *pThis, char *buffer)
                                        DAVINCI_USB_INT_SOURCE_REG),
                        musb_readl(pThis->ctrl_base,
                                        DAVINCI_USB_INT_MASK_REG));
-       if (code < 0)
-               return count;
+       if (code <= 0)
+               goto done;
        count += code;
        buffer += code;
 #endif /* DAVINCI */
@@ -558,8 +569,8 @@ static int dump_header_stats(struct musb *pThis, char *buffer)
                        musb_readl(pThis->ctrl_base, TUSB_PRCM_CONF),
                        musb_readl(pThis->ctrl_base, TUSB_PRCM_MNGMT),
                        musb_readl(pThis->ctrl_base, TUSB_INT_MASK));
-       if (code < 0)
-               return count;
+       if (code <= 0)
+               goto done;
        count += code;
        buffer += code;
 #endif /* DAVINCI */
@@ -581,8 +592,8 @@ static int dump_header_stats(struct musb *pThis, char *buffer)
                                                DAVINCI_RXCPPI_RAW_REG),
                                musb_readl(pThis->ctrl_base,
                                                DAVINCI_RXCPPI_INTENAB_REG));
-               if (code < 0)
-                       return count;
+               if (code <= 0)
+                       goto done;
                count += code;
                buffer += code;
        }
@@ -593,13 +604,14 @@ static int dump_header_stats(struct musb *pThis, char *buffer)
                                pThis->pGadgetDriver
                                        ? pThis->pGadgetDriver->driver.name
                                        : "(none)");
-               if (code < 0)
-                       return code;
+               if (code <= 0)
+                       goto done;
                count += code;
                buffer += code;
        }
 #endif
 
+done:
        return count;
 }
 
@@ -746,7 +758,7 @@ static int musb_proc_read(char *page, char **start,
 
        count -= off;
        count -= 1;             /* for NUL at end */
-       if (count < 0)
+       if (count <= 0)
                return -EINVAL;
 
        spin_lock_irqsave(&pThis->Lock, flags);
@@ -773,7 +785,7 @@ static int musb_proc_read(char *page, char **start,
        spin_unlock_irqrestore(&pThis->Lock, flags);
        *eof = 1;
 
-       return (buffer - page) - off;
+       return buffer - page;
 }
 
 void __devexit musb_debug_delete(char *name, struct musb *musb)