blob: 8fa7f256ad8cbe18ef9423a66774df81baeb0cd4 [file] [log] [blame]
/* -----------------------------------------------------------------------------
* Copyright (c) 2011 Ozmo Inc
* Released under the GNU General Public License Version 2 (GPLv2).
*
* This file provides protocol independent part of the implementation of the USB
* service for a PD.
* The implementation of this service is split into two parts the first of which
* is protocol independent and the second contains protocol specific details.
* This split is to allow alternative protocols to be defined.
* The implementation of this service uses ozhcd.c to implement a USB HCD.
* -----------------------------------------------------------------------------
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/timer.h>
#include <linux/sched.h>
#include <linux/netdevice.h>
#include <linux/errno.h>
#include <linux/input.h>
#include <asm/unaligned.h>
#include "ozconfig.h"
#include "ozprotocol.h"
#include "ozeltbuf.h"
#include "ozpd.h"
#include "ozproto.h"
#include "ozusbif.h"
#include "ozhcd.h"
#include "oztrace.h"
#include "ozusbsvc.h"
#include "ozevent.h"
/*------------------------------------------------------------------------------
* This is called once when the driver is loaded to initialise the USB service.
* Context: process
*/
int oz_usb_init(void)
{
oz_event_log(OZ_EVT_SERVICE, 1, OZ_APPID_USB, 0, 0);
return oz_hcd_init();
}
/*------------------------------------------------------------------------------
* This is called once when the driver is unloaded to terminate the USB service.
* Context: process
*/
void oz_usb_term(void)
{
oz_event_log(OZ_EVT_SERVICE, 2, OZ_APPID_USB, 0, 0);
oz_hcd_term();
}
/*------------------------------------------------------------------------------
* This is called when the USB service is started or resumed for a PD.
* Context: softirq
*/
int oz_usb_start(struct oz_pd *pd, int resume)
{
int rc = 0;
struct oz_usb_ctx *usb_ctx;
struct oz_usb_ctx *old_ctx = 0;
oz_event_log(OZ_EVT_SERVICE, 3, OZ_APPID_USB, 0, resume);
if (resume) {
oz_trace("USB service resumed.\n");
return 0;
}
oz_trace("USB service started.\n");
/* Create a USB context in case we need one. If we find the PD already
* has a USB context then we will destroy it.
*/
usb_ctx = kzalloc(sizeof(struct oz_usb_ctx), GFP_ATOMIC);
if (usb_ctx == 0)
return -ENOMEM;
atomic_set(&usb_ctx->ref_count, 1);
usb_ctx->pd = pd;
usb_ctx->stopped = 0;
/* Install the USB context if the PD doesn't already have one.
* If it does already have one then destroy the one we have just
* created.
*/
spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
old_ctx = pd->app_ctx[OZ_APPID_USB-1];
if (old_ctx == 0)
pd->app_ctx[OZ_APPID_USB-1] = usb_ctx;
oz_usb_get(pd->app_ctx[OZ_APPID_USB-1]);
spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
if (old_ctx) {
oz_trace("Already have USB context.\n");
kfree(usb_ctx);
usb_ctx = old_ctx;
} else if (usb_ctx) {
/* Take a reference to the PD. This will be released when
* the USB context is destroyed.
*/
oz_pd_get(pd);
}
/* If we already had a USB context and had obtained a port from
* the USB HCD then just reset the port. If we didn't have a port
* then report the arrival to the USB HCD so we get one.
*/
if (usb_ctx->hport) {
oz_hcd_pd_reset(usb_ctx, usb_ctx->hport);
} else {
usb_ctx->hport = oz_hcd_pd_arrived(usb_ctx);
if (usb_ctx->hport == 0) {
oz_trace("USB hub returned null port.\n");
spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
pd->app_ctx[OZ_APPID_USB-1] = 0;
spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
oz_usb_put(usb_ctx);
rc = -1;
}
}
oz_usb_put(usb_ctx);
return rc;
}
/*------------------------------------------------------------------------------
* This is called when the USB service is stopped or paused for a PD.
* Context: softirq or process
*/
void oz_usb_stop(struct oz_pd *pd, int pause)
{
struct oz_usb_ctx *usb_ctx;
oz_event_log(OZ_EVT_SERVICE, 4, OZ_APPID_USB, 0, pause);
if (pause) {
oz_trace("USB service paused.\n");
return;
}
spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB-1];
pd->app_ctx[OZ_APPID_USB-1] = 0;
spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
if (usb_ctx) {
unsigned long tout = jiffies + HZ;
oz_trace("USB service stopping...\n");
usb_ctx->stopped = 1;
/* At this point the reference count on the usb context should
* be 2 - one from when we created it and one from the hcd
* which claims a reference. Since stopped = 1 no one else
* should get in but someone may already be in. So wait
* until they leave but timeout after 1 second.
*/
while ((atomic_read(&usb_ctx->ref_count) > 2) &&
time_before(jiffies, tout))
;
oz_trace("USB service stopped.\n");
oz_hcd_pd_departed(usb_ctx->hport);
/* Release the reference taken in oz_usb_start.
*/
oz_usb_put(usb_ctx);
}
}
/*------------------------------------------------------------------------------
* This increments the reference count of the context area for a specific PD.
* This ensures this context area does not disappear while still in use.
* Context: softirq
*/
void oz_usb_get(void *hpd)
{
struct oz_usb_ctx *usb_ctx = (struct oz_usb_ctx *)hpd;
atomic_inc(&usb_ctx->ref_count);
}
/*------------------------------------------------------------------------------
* This decrements the reference count of the context area for a specific PD
* and destroys the context area if the reference count becomes zero.
* Context: softirq or process
*/
void oz_usb_put(void *hpd)
{
struct oz_usb_ctx *usb_ctx = (struct oz_usb_ctx *)hpd;
if (atomic_dec_and_test(&usb_ctx->ref_count)) {
oz_trace("Dealloc USB context.\n");
oz_pd_put(usb_ctx->pd);
kfree(usb_ctx);
}
}
/*------------------------------------------------------------------------------
* Context: softirq
*/
int oz_usb_heartbeat(struct oz_pd *pd)
{
struct oz_usb_ctx *usb_ctx;
int rc = 0;
spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
usb_ctx = (struct oz_usb_ctx *)pd->app_ctx[OZ_APPID_USB-1];
if (usb_ctx)
oz_usb_get(usb_ctx);
spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
if (usb_ctx == 0)
return rc;
if (usb_ctx->stopped)
goto done;
if (usb_ctx->hport)
if (oz_hcd_heartbeat(usb_ctx->hport))
rc = 1;
done:
oz_usb_put(usb_ctx);
return rc;
}
/*------------------------------------------------------------------------------
* Context: softirq
*/
int oz_usb_stream_create(void *hpd, u8 ep_num)
{
struct oz_usb_ctx *usb_ctx = (struct oz_usb_ctx *)hpd;
struct oz_pd *pd = usb_ctx->pd;
oz_trace("oz_usb_stream_create(0x%x)\n", ep_num);
if (pd->mode & OZ_F_ISOC_NO_ELTS) {
oz_isoc_stream_create(pd, ep_num);
} else {
oz_pd_get(pd);
if (oz_elt_stream_create(&pd->elt_buff, ep_num,
4*pd->max_tx_size)) {
oz_pd_put(pd);
return -1;
}
}
return 0;
}
/*------------------------------------------------------------------------------
* Context: softirq
*/
int oz_usb_stream_delete(void *hpd, u8 ep_num)
{
struct oz_usb_ctx *usb_ctx = (struct oz_usb_ctx *)hpd;
if (usb_ctx) {
struct oz_pd *pd = usb_ctx->pd;
if (pd) {
oz_trace("oz_usb_stream_delete(0x%x)\n", ep_num);
if (pd->mode & OZ_F_ISOC_NO_ELTS) {
oz_isoc_stream_delete(pd, ep_num);
} else {
if (oz_elt_stream_delete(&pd->elt_buff, ep_num))
return -1;
oz_pd_put(pd);
}
}
}
return 0;
}
/*------------------------------------------------------------------------------
* Context: softirq or process
*/
void oz_usb_request_heartbeat(void *hpd)
{
struct oz_usb_ctx *usb_ctx = (struct oz_usb_ctx *)hpd;
if (usb_ctx && usb_ctx->pd)
oz_pd_request_heartbeat(usb_ctx->pd);
}