Commit de536e30 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

greybus: ap message loop added.

parent 27fb8310

drivers/staging/greybus/Makefile

+8 −1
Original line number Diff line number Diff line 
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

drivers/staging/greybus/ap.c

0 → 100644
+125 −0
Original line number Diff line number Diff line 
/*

 * 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);

}

drivers/staging/greybus/core.c

+11 −3
Original line number Diff line number Diff line
@@ -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);

drivers/staging/greybus/debugfs.c

+2 −2
Original line number Diff line number Diff line
@@ -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);

}

drivers/staging/greybus/es1-ap-usb.c

+63 −1
Original line number Diff line number Diff line
@@ -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)