USB: xhci: Allow allocation of commands without input contexts.

The xhci_command structure is the basic structure for issuing commands to
the xHCI hardware.  It contains a struct completion (so that the issuing
function can wait on the command), command status, and a input context
that is used to pass information to the hardware.  Not all commands need
the input context, so make it optional to allocate.  Allow
xhci_free_container_ctx() to be passed a NULL input context, to make
freeing the xhci_command structure simple.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
index 451f53e..17f1caf 100644 (file)
--- a/drivers/usb/host/xhci-hcd.c
+++ b/drivers/usb/host/xhci-hcd.c
@@ -1679,7 +1679,7 @@ int xhci_update_hub_device(struct usb_hcd *hcd, struct usb_device *hdev,
                xhci_warn(xhci, "Cannot update hub desc for unknown device.\n");
                return -EINVAL;
        }
-       config_cmd = xhci_alloc_command(xhci, true, mem_flags);
+       config_cmd = xhci_alloc_command(xhci, true, true, mem_flags);
        if (!config_cmd) {
                xhci_dbg(xhci, "Could not allocate xHCI command structure.\n");
                return -ENOMEM;

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 1f1f8a0..8045bc6 100644 (file)
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -267,6 +267,8 @@ struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
 void xhci_free_container_ctx(struct xhci_hcd *xhci,
                             struct xhci_container_ctx *ctx)
 {
+       if (!ctx)
+               return;
        dma_pool_free(xhci->device_pool, ctx->bytes, ctx->dma);
        kfree(ctx);
 }
@@ -844,7 +846,8 @@ static void scratchpad_free(struct xhci_hcd *xhci)
 }
 
 struct xhci_command *xhci_alloc_command(struct xhci_hcd *xhci,
-               bool allocate_completion, gfp_t mem_flags)
+               bool allocate_in_ctx, bool allocate_completion,
+               gfp_t mem_flags)
 {
        struct xhci_command *command;
 
@@ -852,11 +855,14 @@ struct xhci_command *xhci_alloc_command(struct xhci_hcd *xhci,
        if (!command)
                return NULL;
 
-       command->in_ctx =
-               xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_INPUT, mem_flags);
-       if (!command->in_ctx) {
-               kfree(command);
-               return NULL;
+       if (allocate_in_ctx) {
+               command->in_ctx =
+                       xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_INPUT,
+                                       mem_flags);
+               if (!command->in_ctx) {
+                       kfree(command);
+                       return NULL;
+               }
        }
 
        if (allocate_completion) {

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 61747f3..902be96 100644 (file)
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1237,7 +1237,8 @@ void xhci_free_or_cache_endpoint_ring(struct xhci_hcd *xhci,
                struct xhci_virt_device *virt_dev,
                unsigned int ep_index);
 struct xhci_command *xhci_alloc_command(struct xhci_hcd *xhci,
-               bool allocate_completion, gfp_t mem_flags);
+               bool allocate_in_ctx, bool allocate_completion,
+               gfp_t mem_flags);
 void xhci_free_command(struct xhci_hcd *xhci,
                struct xhci_command *command);