firewire: ohci: restart iso DMA contexts on resume from low power mode

Restore iso channels DMA so that iso channels could continue to work
after resume from RAM/disk.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 46 insertions, 8 deletions

diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 3a908038ff62..5e5d5d3d43d1 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -18,6 +18,7 @@
  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
+#include <linux/bitops.h>
 #include <linux/bug.h>
 #include <linux/compiler.h>
 #include <linux/delay.h>
@@ -153,6 +154,7 @@ struct context {
         descriptor_callback_t callback;
 
         struct tasklet_struct tasklet;
+        bool active;
 };
 
 #define IT_HEADER_SY(v)          ((v) <<  0)
@@ -168,6 +170,9 @@ struct iso_context {
         int excess_bytes;
         void *header;
         size_t header_length;
+
+        u8 sync;
+        u8 tags;
 };
 
 #define CONFIG_ROM_SIZE 1024
@@ -184,7 +189,8 @@ struct fw_ohci {
         u32 bus_time;
         bool is_root;
         bool csr_state_setclear_abdicate;
-
+        int n_ir;
+        int n_it;
         /*
          * Spinlock for accessing fw_ohci data.  Never call out of
          * this driver with this lock held.
@@ -1161,6 +1167,7 @@ static struct descriptor *context_get_descriptors(struct context *ctx,
 static void context_run(struct context *ctx, u32 extra)
 {
         struct fw_ohci *ohci = ctx->ohci;
+        ctx->active = true;
 
         reg_write(ohci, COMMAND_PTR(ctx->regs),
                   le32_to_cpu(ctx->last->branch_address));
@@ -1192,6 +1199,7 @@ static void context_stop(struct context *ctx)
         u32 reg;
         int i;
 
+        ctx->active = false;
         reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
         flush_writes(ctx->ohci);
 
@@ -2641,6 +2649,10 @@ static int ohci_start_iso(struct fw_iso_context *base,
                 reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
                 reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
                 context_run(&ctx->context, control);
+
+                ctx->sync = sync;
+                ctx->tags = tags;
+
                 break;
         }
 
@@ -2738,6 +2750,26 @@ static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
         return ret;
 }
 
+#ifdef CONFIG_PM
+static void ohci_resume_iso_dma(struct fw_ohci *ohci)
+{
+        int i;
+        struct iso_context *ctx;
+
+        for (i = 0 ; i < ohci->n_ir ; i++) {
+                ctx = &ohci->ir_context_list[i];
+                if (ctx->context.active)
+                        ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
+        }
+
+        for (i = 0 ; i < ohci->n_it ; i++) {
+                ctx = &ohci->it_context_list[i];
+                if (ctx->context.active)
+                        ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
+        }
+}
+#endif
+
 static int queue_iso_transmit(struct iso_context *ctx,
                               struct fw_iso_packet *packet,
                               struct fw_iso_buffer *buffer,
@@ -3047,7 +3079,7 @@ static int __devinit pci_probe(struct pci_dev *dev,
         struct fw_ohci *ohci;
         u32 bus_options, max_receive, link_speed, version;
         u64 guid;
-        int i, err, n_ir, n_it;
+        int i, err;
         size_t size;
 
         ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
@@ -3141,15 +3173,15 @@ static int __devinit pci_probe(struct pci_dev *dev,
         ohci->ir_context_channels = ~0ULL;
         ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
         reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
-        n_ir = hweight32(ohci->ir_context_mask);
-        size = sizeof(struct iso_context) * n_ir;
+        ohci->n_ir = hweight32(ohci->ir_context_mask);
+        size = sizeof(struct iso_context) * ohci->n_ir;
         ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
 
         reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
         ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
         reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
-        n_it = hweight32(ohci->it_context_mask);
-        size = sizeof(struct iso_context) * n_it;
+        ohci->n_it = hweight32(ohci->it_context_mask);
+        size = sizeof(struct iso_context) * ohci->n_it;
         ohci->it_context_list = kzalloc(size, GFP_KERNEL);
 
         if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
@@ -3174,7 +3206,7 @@ static int __devinit pci_probe(struct pci_dev *dev,
         fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
                   "%d IR + %d IT contexts, quirks 0x%x\n",
                   dev_name(&dev->dev), version >> 16, version & 0xff,
-                  n_ir, n_it, ohci->quirks);
+                  ohci->n_ir, ohci->n_it, ohci->quirks);
 
         return 0;
 
@@ -3291,7 +3323,13 @@ static int pci_resume(struct pci_dev *dev)
                 reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
         }
 
-        return ohci_enable(&ohci->card, NULL, 0);
+        err = ohci_enable(&ohci->card, NULL, 0);
+
+        if (err)
+                return err;
+
+        ohci_resume_iso_dma(ohci);
+        return 0;
 }
 #endif