]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/commitdiff
greybus: ap message loop added.
authorGreg Kroah-Hartman <greg@kroah.com>
Sun, 31 Aug 2014 23:17:04 +0000 (16:17 -0700)
committerGreg Kroah-Hartman <greg@kroah.com>
Sun, 31 Aug 2014 23:17:04 +0000 (16:17 -0700)
drivers/staging/greybus/Makefile
drivers/staging/greybus/ap.c [new file with mode: 0644]
drivers/staging/greybus/core.c
drivers/staging/greybus/debugfs.c
drivers/staging/greybus/es1-ap-usb.c
drivers/staging/greybus/greybus.h

index 3badfefd237d1c57870bc63479dde3572ba6097d..9815e8abac56361a480ab796d04bcc2244f8b9d4 100644 (file)
@@ -1,4 +1,11 @@
-greybus-y := core.o gbuf.o debugfs.o i2c-gb.o gpio-gb.o sdio-gb.o uart-gb.o
+greybus-y :=   core.o          \
+               gbuf.o          \
+               debugfs.o       \
+               ap.o            \
+               i2c-gb.o        \
+               gpio-gb.o       \
+               sdio-gb.o       \
+               uart-gb.o
 
 obj-m += greybus.o
 obj-m += es1-ap-usb.o
diff --git a/drivers/staging/greybus/ap.c b/drivers/staging/greybus/ap.c
new file mode 100644 (file)
index 0000000..5189e8e
--- /dev/null
@@ -0,0 +1,125 @@
+/*
+ * Greybus "AP" message loop handling
+ *
+ * Copyright 2014 Google Inc.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/kthread.h>
+#include <linux/device.h>
+#include "greybus.h"
+
+struct ap_msg {
+       u8 *data;
+       int size;
+       struct list_head list;
+};
+
+static LIST_HEAD(ap_msg_list);
+static spinlock_t ap_msg_list_lock;
+static struct task_struct *ap_thread;
+static wait_queue_head_t ap_wait;
+
+static struct ap_msg *get_ap_msg(void)
+{
+       struct ap_msg *ap_msg;
+       unsigned long flags;
+
+       spin_lock_irqsave(&ap_msg_list_lock, flags);
+
+       ap_msg = list_first_entry_or_null(&ap_msg_list, struct ap_msg, list);
+       if (ap_msg != NULL)
+               list_del(&ap_msg->list);
+       spin_unlock_irqrestore(&ap_msg_list_lock, flags);
+
+       return ap_msg;
+}
+
+static int ap_process_loop(void *data)
+{
+       struct ap_msg *ap_msg;
+
+       while (!kthread_should_stop()) {
+               wait_event_interruptible(ap_wait, kthread_should_stop());
+
+               if (kthread_should_stop())
+                       break;
+
+               /* Get some data off of the ap list and process it */
+               ap_msg = get_ap_msg();
+               if (!ap_msg)
+                       continue;
+
+               // FIXME - process the message
+
+               /* clean the message up */
+               kfree(ap_msg->data);
+               kfree(ap_msg);
+       }
+       return 0;
+}
+
+int gb_new_ap_msg(u8 *data, int size)
+{
+       struct ap_msg *ap_msg;
+       unsigned long flags;
+
+       /*
+        * Totally naive copy the message into a new structure that we slowly
+        * create and add it to the list.  Let's get this working, the odds of
+        * this being any "slow path" for AP messages is really low at this
+        * point in time, but you never know, so this comment is here to point
+        * out that maybe we should use a slab allocator, or even just not copy
+        * the data, but use it directly and force the urbs to be "new" each
+        * time.
+        */
+
+       /* Note - this can, and will, be called in interrupt context. */
+       ap_msg = kmalloc(sizeof(*ap_msg), GFP_ATOMIC);
+       if (!ap_msg)
+               return -ENOMEM;
+       ap_msg->data = kmalloc(size, GFP_ATOMIC);
+       if (!ap_msg->data) {
+               kfree(ap_msg);
+               return -ENOMEM;
+       }
+       memcpy(ap_msg->data, data, size);
+       ap_msg->size = size;
+
+       spin_lock_irqsave(&ap_msg_list_lock, flags);
+       list_add(&ap_msg->list, &ap_msg_list);
+       spin_unlock_irqrestore(&ap_msg_list_lock, flags);
+
+       /* kick our thread to handle the message */
+       wake_up_interruptible(&ap_wait);
+
+       return 0;
+}
+
+int gb_thread_init(void)
+{
+       init_waitqueue_head(&ap_wait);
+       spin_lock_init(&ap_msg_list_lock);
+
+       ap_thread = kthread_run(ap_process_loop, NULL, "greybus_ap");
+       if (IS_ERR(ap_thread))
+               return PTR_ERR(ap_thread);
+
+       return 0;
+}
+
+void gb_thread_destroy(void)
+{
+       kthread_stop(ap_thread);
+}
+
+
index 143882a523e3754c43cd3d6eed5cc7d4dbe99375..887aa601fd22dc22aafeb5ab02526346c27e29aa 100644 (file)
@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/kernel.h>
+#include <linux/kthread.h>
 #include <linux/device.h>
 
 #include "greybus.h"
@@ -199,7 +200,7 @@ static int __init gb_init(void)
 {
        int retval;
 
-       retval = greybus_debugfs_init();
+       retval = gb_debugfs_init();
        if (retval)
                return retval;
 
@@ -207,6 +208,10 @@ static int __init gb_init(void)
        if (retval)
                goto error_bus;
 
+       retval = gb_thread_init();
+       if (retval)
+               goto error_thread;
+
        // FIXME - more gb core init goes here
 
        retval = gb_tty_init();
@@ -216,10 +221,13 @@ static int __init gb_init(void)
        return 0;
 
 error_tty:
+       gb_thread_destroy();
+
+error_thread:
        bus_unregister(&greybus_bus_type);
 
 error_bus:
-       greybus_debugfs_cleanup();
+       gb_debugfs_cleanup();
 
        return retval;
 }
@@ -228,7 +236,7 @@ static void __exit gb_exit(void)
 {
        gb_tty_exit();
        bus_unregister(&greybus_bus_type);
-       greybus_debugfs_cleanup();
+       gb_debugfs_cleanup();
 }
 
 module_init(gb_init);
index 097b32d2bb56314422c460839e90c44dc4521e62..4e313f1a514375aad1999e0d28e9c078b285d547 100644 (file)
@@ -19,7 +19,7 @@
 
 static struct dentry *gb_debug_root;
 
-int greybus_debugfs_init(void)
+int gb_debugfs_init(void)
 {
        gb_debug_root = debugfs_create_dir("greybus", NULL);
        if (!gb_debug_root)
@@ -28,7 +28,7 @@ int greybus_debugfs_init(void)
        return 0;
 }
 
-void greybus_debugfs_cleanup(void)
+void gb_debugfs_cleanup(void)
 {
        debugfs_remove_recursive(gb_debug_root);
 }
index bebef6dbae7b28857ad8badd06e02290e19342d3..abf9dfe664500b90a0b01b34730944392f21f03f 100644 (file)
@@ -10,7 +10,7 @@
 #include <linux/slab.h>
 #include <linux/errno.h>
 #include <linux/usb.h>
-
+#include "greybus.h"
 
 static const struct usb_device_id id_table[] = {
        { USB_DEVICE(0x0000, 0x0000) },         // FIXME
@@ -34,6 +34,68 @@ struct es1_ap_dev {
  */
 static struct es1_ap_dev *es1_ap_dev;
 
+static void ap_in_callback(struct urb *urb)
+{
+       struct device *dev = &urb->dev->dev;
+       int status = urb->status;
+       int retval;
+
+       switch (status) {
+       case 0:
+               break;
+       case -EOVERFLOW:
+               dev_err(dev, "%s: overflow actual length is %d\n",
+                       __func__, urb->actual_length);
+       case -ECONNRESET:
+       case -ENOENT:
+       case -ESHUTDOWN:
+       case -EILSEQ:
+               /* device is gone, stop sending */
+               return;
+       default:
+               dev_err(dev, "%s: unknown status %d\n", __func__, status);
+               goto exit;
+       }
+
+       /* We have a message, create a new message structure, add it to the
+        * list, and wake up our thread that will process the messages.
+        */
+       gb_new_ap_msg(urb->transfer_buffer, urb->actual_length);
+
+exit:
+       /* resubmit the urb to get more messages */
+       retval = usb_submit_urb(urb, GFP_ATOMIC);
+       if (retval)
+               dev_err(dev, "Can not submit urb for AP data: %d\n", retval);
+}
+
+static void ap_out_callback(struct urb *urb)
+{
+       struct device *dev = &urb->dev->dev;
+       int status = urb->status;
+
+       switch (status) {
+       case 0:
+               break;
+       case -EOVERFLOW:
+               dev_err(dev, "%s: overflow actual length is %d\n",
+                       __func__, urb->actual_length);
+       case -ECONNRESET:
+       case -ENOENT:
+       case -ESHUTDOWN:
+       case -EILSEQ:
+               /* device is gone, stop sending */
+               return;
+       default:
+               dev_err(dev, "%s: unknown status %d\n", __func__, status);
+               goto exit;
+       }
+
+       // FIXME - queue up next AP message to send???
+exit:
+       return;
+}
+
 
 static int ap_probe(struct usb_interface *interface,
                    const struct usb_device_id *id)
index 7ce8c6ef02875fe69c78184366292847186063eb..9b0b41bb2a65c1d1620bd9075084433300829b6d 100644 (file)
@@ -176,8 +176,16 @@ void greybus_deregister(struct greybus_driver *driver);
 
 int greybus_disabled(void);
 
-int greybus_debugfs_init(void);
-void greybus_debugfs_cleanup(void);
+
+/* Internal functions to gb module, move to internal .h file eventually. */
+
+int gb_new_ap_msg(u8 *data, int length);
+int gb_thread_init(void);
+void gb_thread_destroy(void);
+int gb_debugfs_init(void);
+void gb_debugfs_cleanup(void);
+
+
 
 #endif /* __KERNEL__ */
 #endif /* __LINUX_GREYBUS_H */