usb: r8a66597-udc buffer management update

This patch updates the r8a66597-udc buffer management code.

Use fixed buffers for bulk and isochronous pipes, also make
sure to handle the isochronous-as-bulk case. With fixed buffers
there is no need to keep track of used buffers with bi_bufnum.

Also, this fixes a potential buffer offset problem where the
base offset incorrectly varies with the number of pipes used.

The m66592 driver recently got fixed in a similar way.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 11 insertions, 22 deletions

diff --git a/drivers/usb/gadget/r8a66597-udc.c b/drivers/usb/gadget/r8a66597-udc.c
index c65753ffe0f0..956618400a7c 100644
--- a/drivers/usb/gadget/r8a66597-udc.c
+++ b/drivers/usb/gadget/r8a66597-udc.c
@@ -252,24 +252,27 @@ static int pipe_buffer_setting(struct r8a66597 *r8a66597,
                 buf_bsize = 0;
                 break;
         case R8A66597_BULK:
-                bufnum = r8a66597->bi_bufnum +
-                         (info->pipe - R8A66597_BASE_PIPENUM_BULK) * 16;
-                r8a66597->bi_bufnum += 16;
+                /* isochronous pipes may be used as bulk pipes */
+                if (info->pipe > R8A66597_BASE_PIPENUM_BULK)
+                        bufnum = info->pipe - R8A66597_BASE_PIPENUM_BULK;
+                else
+                        bufnum = info->pipe - R8A66597_BASE_PIPENUM_ISOC;
+
+                bufnum = R8A66597_BASE_BUFNUM + (bufnum * 16);
                 buf_bsize = 7;
                 pipecfg |= R8A66597_DBLB;
                 if (!info->dir_in)
                         pipecfg |= R8A66597_SHTNAK;
                 break;
         case R8A66597_ISO:
-                bufnum = r8a66597->bi_bufnum +
+                bufnum = R8A66597_BASE_BUFNUM +
                          (info->pipe - R8A66597_BASE_PIPENUM_ISOC) * 16;
-                r8a66597->bi_bufnum += 16;
                 buf_bsize = 7;
                 break;
         }
-        if (r8a66597->bi_bufnum > R8A66597_MAX_BUFNUM) {
-                printk(KERN_ERR "r8a66597 pipe memory is insufficient(%d)\n",
-                                r8a66597->bi_bufnum);
+
+        if (buf_bsize && ((bufnum + 16) >= R8A66597_MAX_BUFNUM)) {
+                pr_err(KERN_ERR "r8a66597 pipe memory is insufficient\n");
                 return -ENOMEM;
         }
 
@@ -289,17 +292,6 @@ static void pipe_buffer_release(struct r8a66597 *r8a66597,
         if (info->pipe == 0)
                 return;
 
-        switch (info->type) {
-        case R8A66597_BULK:
-                if (is_bulk_pipe(info->pipe))
-                        r8a66597->bi_bufnum -= 16;
-                break;
-        case R8A66597_ISO:
-                if (is_isoc_pipe(info->pipe))
-                        r8a66597->bi_bufnum -= 16;
-                break;
-        }
-
         if (is_bulk_pipe(info->pipe))
                 r8a66597->bulk--;
         else if (is_interrupt_pipe(info->pipe))
@@ -1553,8 +1545,6 @@ static int __init r8a66597_probe(struct platform_device *pdev)
         r8a66597->timer.data = (unsigned long)r8a66597;
         r8a66597->reg = (unsigned long)reg;
 
-        r8a66597->bi_bufnum = R8A66597_BASE_BUFNUM;
-
 #ifdef CONFIG_HAVE_CLK
         if (r8a66597->pdata->on_chip) {
                 snprintf(clk_name, sizeof(clk_name), "usb%d", pdev->id);
diff --git a/drivers/usb/gadget/r8a66597-udc.h b/drivers/usb/gadget/r8a66597-udc.h
index 7d9a325e7b6d..e653575d4ceb 100644
--- a/drivers/usb/gadget/r8a66597-udc.h
+++ b/drivers/usb/gadget/r8a66597-udc.h
@@ -112,7 +112,6 @@ struct r8a66597 {
         u16                     old_dvsq;
 
         /* pipe config */
-        unsigned short bi_bufnum;       /* bulk and isochronous's bufnum */
         unsigned char bulk;
         unsigned char interrupt;
         unsigned char isochronous;