firewire: ohci: work around VIA and NEC PHY packet reception bug

[net-next-2.6.git] / drivers / firewire / ohci.c

diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 4bda1c1b74bab609ba37bf37645ea537eabbfe16..be29b0bb247101442a63fa623467e98ad7b77524 100644 (file)
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -25,7 +25,6 @@
 #include <linux/dma-mapping.h>
 #include <linux/firewire.h>
 #include <linux/firewire-constants.h>
-#include <linux/gfp.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
@@ -37,8 +36,10 @@
 #include <linux/mutex.h>
 #include <linux/pci.h>
 #include <linux/pci_ids.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
+#include <linux/time.h>
 
 #include <asm/byteorder.h>
 #include <asm/page.h>
@@ -693,7 +694,15 @@ static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
        log_ar_at_event('R', p.speed, p.header, evt);
 
        /*
-        * The OHCI bus reset handler synthesizes a phy packet with
+        * Several controllers, notably from NEC and VIA, forget to
+        * write ack_complete status at PHY packet reception.
+        */
+       if (evt == OHCI1394_evt_no_status &&
+           (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
+               p.ack = ACK_COMPLETE;
+
+       /*
+        * The OHCI bus reset handler synthesizes a PHY packet with
         * the new generation number when a bus reset happens (see
         * section 8.4.2.3).  This helps us determine when a request
         * was received and make sure we send the response in the same
@@ -1256,7 +1265,7 @@ static void handle_local_lock(struct fw_ohci *ohci,
                              struct fw_packet *packet, u32 csr)
 {
        struct fw_packet response;
-       int tcode, length, ext_tcode, sel;
+       int tcode, length, ext_tcode, sel, try;
        __be32 *payload, lock_old;
        u32 lock_arg, lock_data;
 
@@ -1283,21 +1292,26 @@ static void handle_local_lock(struct fw_ohci *ohci,
        reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
        reg_write(ohci, OHCI1394_CSRControl, sel);
 
-       if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000)
-               lock_old = cpu_to_be32(reg_read(ohci, OHCI1394_CSRData));
-       else
-               fw_notify("swap not done yet\n");
+       for (try = 0; try < 20; try++)
+               if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
+                       lock_old = cpu_to_be32(reg_read(ohci,
+                                                       OHCI1394_CSRData));
+                       fw_fill_response(&response, packet->header,
+                                        RCODE_COMPLETE,
+                                        &lock_old, sizeof(lock_old));
+                       goto out;
+               }
+
+       fw_error("swap not done (CSR lock timeout)\n");
+       fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
 
-       fw_fill_response(&response, packet->header,
-                        RCODE_COMPLETE, &lock_old, sizeof(lock_old));
  out:
        fw_core_handle_response(&ohci->card, &response);
 }
 
 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
 {
-       u64 offset;
-       u32 csr;
+       u64 offset, csr;
 
        if (ctx == &ctx->ohci->at_request_ctx) {
                packet->ack = ACK_PENDING;
@@ -1523,7 +1537,7 @@ static void bus_reset_tasklet(unsigned long data)
         * was set up before this reset, the old one is now no longer
         * in use and we can free it. Update the config rom pointers
         * to point to the current config rom and clear the
-        * next_config_rom pointer so a new udpate can take place.
+        * next_config_rom pointer so a new update can take place.
         */
 
        if (ohci->next_config_rom != NULL) {