/*
* Copyright (c) 2011 Vojtech Horky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup drvusbvhc
* @{
*/
/** @file
* Connection handling of calls from virtual device (implementation).
*/
#include <assert.h>
#include <errno.h>
#include <ddf/driver.h>
#include <usbvirt/ipc.h>
#include <usb/debug.h>
#include <async.h>
#include "vhcd.h"
#define PLUGGED_DEVICE_NAME_MAXLEN 256
static fibril_local uintptr_t plugged_device_handle = 0;
/*
* The explicit "initial-exec" TLS model attribute is a temporary workaround
* for a bug in GCC (observed in 14.2 and 15.2) that manifests in combination
* with the binutils 2.45 linker on MIPS.
*
* Without the attribute, the linker reports the following error:
*
* can't find matching LO16 reloc against `plugged_device_name' for
* R_MIPS_TLS_TPREL_HI16 at 0x238 in section
* `.text.default_connection_handler'
*
* The immediate cause is a missing R_MIPS_TLS_TPREL_LO16 relocation that
* matches the R_MIPS_TLS_TPREL_HI16 relocation. The root cause is probably
* an aggressive optimization in the compiler that removes the relocation
* despite being needed.
*/
static fibril_local char plugged_device_name[PLUGGED_DEVICE_NAME_MAXLEN + 1]
__attribute__((tls_model("initial-exec"))) = "<unknown>";
/** Receive device name.
*
* @warning Errors are silently ignored.
*
* @param sess Session to the virtual device.
*
*/
static void receive_device_name(async_sess_t *sess)
{
async_exch_t *exch = async_exchange_begin(sess);
aid_t opening_request = async_send_0(exch, IPC_M_USBVIRT_GET_NAME, NULL);
if (opening_request == 0) {
async_exchange_end(exch);
return;
}
ipc_call_t data_request_call;
aid_t data_request = async_data_read(exch, plugged_device_name,
PLUGGED_DEVICE_NAME_MAXLEN, &data_request_call);
async_exchange_end(exch);
if (data_request == 0) {
async_forget(opening_request);
return;
}
errno_t data_request_rc;
errno_t opening_request_rc;
async_wait_for(data_request, &data_request_rc);
async_wait_for(opening_request, &opening_request_rc);
if ((data_request_rc != EOK) || (opening_request_rc != EOK))
return;
size_t len = ipc_get_arg2(&data_request_call);
plugged_device_name[len] = 0;
}
/** Default handler for IPC methods not handled by DDF.
*
* @param fun Device handling the call.
* @param icall Call data.
*
*/
void default_connection_handler(ddf_fun_t *fun, ipc_call_t *icall)
{
vhc_data_t *vhc = ddf_fun_data_get(fun);
async_sess_t *callback =
async_callback_receive_start(EXCHANGE_SERIALIZE, icall);
if (callback) {
errno_t rc = vhc_virtdev_plug(vhc, callback, &plugged_device_handle);
if (rc != EOK) {
async_answer_0(icall, rc);
async_hangup(callback);
return;
}
async_answer_0(icall, EOK);
receive_device_name(callback);
usb_log_info("New virtual device `%s' (id: %" PRIxn ").",
plugged_device_name, plugged_device_handle);
} else
async_answer_0(icall, EINVAL);
}
/** Callback when client disconnects.
*
* Used to unplug virtual USB device.
*
* @param fun
*/
void on_client_close(ddf_fun_t *fun)
{
vhc_data_t *vhc = ddf_fun_data_get(fun);
if (plugged_device_handle != 0) {
usb_log_info("Virtual device `%s' disconnected (id: %" PRIxn ").",
plugged_device_name, plugged_device_handle);
vhc_virtdev_unplug(vhc, plugged_device_handle);
}
}
/**
* @}
*/