usb: m66592-udc buffer management update

This patch updates the m66592-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.

With this patch applied it is possible to use m66592-udc for
both Ethernet and Serial using CONFIG_USB_CDC_COMPOSITE.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 12 insertions, 23 deletions

diff --git a/drivers/usb/gadget/m66592-udc.c b/drivers/usb/gadget/m66592-udc.c
index 43dcf9e1af6b..0dddd2f8ff35 100644
--- a/drivers/usb/gadget/m66592-udc.c
+++ b/drivers/usb/gadget/m66592-udc.c
@@ -37,7 +37,7 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Yoshihiro Shimoda");
 MODULE_ALIAS("platform:m66592_udc");
 
-#define DRIVER_VERSION  "18 Oct 2007"
+#define DRIVER_VERSION  "26 Jun 2009"
 
 /* module parameters */
 #if defined(CONFIG_SUPERH_BUILT_IN_M66592)
@@ -276,24 +276,27 @@ static int pipe_buffer_setting(struct m66592 *m66592,
                 buf_bsize = 0;
                 break;
         case M66592_BULK:
-                bufnum = m66592->bi_bufnum +
-                         (info->pipe - M66592_BASE_PIPENUM_BULK) * 16;
-                m66592->bi_bufnum += 16;
+                /* isochronous pipes may be used as bulk pipes */
+                if (info->pipe > M66592_BASE_PIPENUM_BULK)
+                        bufnum = info->pipe - M66592_BASE_PIPENUM_BULK;
+                else
+                        bufnum = info->pipe - M66592_BASE_PIPENUM_ISOC;
+
+                bufnum = M66592_BASE_BUFNUM + (bufnum * 16);
                 buf_bsize = 7;
                 pipecfg |= M66592_DBLB;
                 if (!info->dir_in)
                         pipecfg |= M66592_SHTNAK;
                 break;
         case M66592_ISO:
-                bufnum = m66592->bi_bufnum +
+                bufnum = M66592_BASE_BUFNUM +
                          (info->pipe - M66592_BASE_PIPENUM_ISOC) * 16;
-                m66592->bi_bufnum += 16;
                 buf_bsize = 7;
                 break;
         }
-        if (m66592->bi_bufnum > M66592_MAX_BUFNUM) {
-                pr_err("m66592 pipe memory is insufficient(%d)\n",
-                                m66592->bi_bufnum);
+
+        if (buf_bsize && ((bufnum + 16) >= M66592_MAX_BUFNUM)) {
+                pr_err("m66592 pipe memory is insufficient\n");
                 return -ENOMEM;
         }
 
@@ -313,17 +316,6 @@ static void pipe_buffer_release(struct m66592 *m66592,
         if (info->pipe == 0)
                 return;
 
-        switch (info->type) {
-        case M66592_BULK:
-                if (is_bulk_pipe(info->pipe))
-                        m66592->bi_bufnum -= 16;
-                break;
-        case M66592_ISO:
-                if (is_isoc_pipe(info->pipe))
-                        m66592->bi_bufnum -= 16;
-                break;
-        }
-
         if (is_bulk_pipe(info->pipe)) {
                 m66592->bulk--;
         } else if (is_interrupt_pipe(info->pipe))
@@ -1603,8 +1595,6 @@ static int __init m66592_probe(struct platform_device *pdev)
         m66592->timer.data = (unsigned long)m66592;
         m66592->reg = reg;
 
-        m66592->bi_bufnum = M66592_BASE_BUFNUM;
-
         ret = request_irq(irq, m66592_irq, IRQF_DISABLED | IRQF_SHARED,
                         udc_name, m66592);
         if (ret < 0) {
diff --git a/drivers/usb/gadget/m66592-udc.h b/drivers/usb/gadget/m66592-udc.h
index 286ce07e7960..9a9c2bf9fbd5 100644
--- a/drivers/usb/gadget/m66592-udc.h
+++ b/drivers/usb/gadget/m66592-udc.h
@@ -506,7 +506,6 @@ struct m66592 {
         int interrupt;
         int isochronous;
         int num_dma;
-        int bi_bufnum;  /* bulk and isochronous's bufnum */
 };
 
 #define gadget_to_m66592(_gadget) container_of(_gadget, struct m66592, gadget)