linux-firmware/carl9170fw/carlfw/usb/usb.c

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/*
* carl9170 firmware - used by the ar9170 wireless device
*
* USB Controller
*
* Copyright (c) 2000-2005 ZyDAS Technology Corporation
* Copyright (c) 2007-2009 Atheros Communications, Inc.
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2009-2011 Christian Lamparter <chunkeey@googlemail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "carl9170.h"
#include "usb.h"
#include "printf.h"
#include "rom.h"
/*
* NB: The firmware has to write into these structures
* so don't try to make them "const".
*/
static struct ar9170_usb_config usb_config_highspeed = {
.cfg = {
.bLength = USB_DT_CONFIG_SIZE,
.bDescriptorType = USB_DT_CONFIG,
.wTotalLength = cpu_to_le16(sizeof(usb_config_highspeed)),
.bNumInterfaces = 1,
.bConfigurationValue = 1,
.iConfiguration = 0,
.bmAttributes = USB_CONFIG_ATT_ONE |
#ifdef CONFIG_CARL9170FW_WOL
USB_CONFIG_ATT_WAKEUP |
#endif /* CONFIG_CARL9170FW_WOL */
0,
.bMaxPower = 0xfa, /* 500 mA */
},
.intf = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bAlternateSetting = 0,
.bNumEndpoints = AR9170_USB_NUM_EXTRA_EP,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.bInterfaceSubClass = USB_SUBCLASS_VENDOR_SPEC,
.bInterfaceProtocol = 0,
.iInterface = 0,
},
.ep = {
{ /* EP 1 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT | AR9170_USB_EP_TX,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(512),
.bInterval = 0,
},
{ /* EP 2 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN | AR9170_USB_EP_RX,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(512),
.bInterval = 0,
},
{ /* EP 3 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN | AR9170_USB_EP_IRQ,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(64),
.bInterval = 1,
},
{ /* EP 4 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT | AR9170_USB_EP_CMD,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(64),
.bInterval = 1,
},
},
};
static struct ar9170_usb_config usb_config_fullspeed = {
.cfg = {
.bLength = USB_DT_CONFIG_SIZE,
.bDescriptorType = USB_DT_CONFIG,
.wTotalLength = cpu_to_le16(sizeof(usb_config_fullspeed)),
.bNumInterfaces = 1,
.bConfigurationValue = 1,
.iConfiguration = 0,
.bmAttributes = USB_CONFIG_ATT_ONE |
#ifdef CONFIG_CARL9170FW_WOL
USB_CONFIG_ATT_WAKEUP |
#endif /* CONFIG_CARL9170FW_WOL */
0,
.bMaxPower = 0xfa, /* 500 mA */
},
.intf = {
.bLength = USB_DT_INTERFACE_SIZE,
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bAlternateSetting = 0,
.bNumEndpoints = AR9170_USB_NUM_EXTRA_EP,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.bInterfaceSubClass = USB_SUBCLASS_VENDOR_SPEC,
.bInterfaceProtocol = 0,
.iInterface = 0,
},
.ep = {
{ /* EP 1 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT | AR9170_USB_EP_TX,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(64),
.bInterval = 0,
},
{ /* EP 2 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN | AR9170_USB_EP_RX,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(64),
.bInterval = 0,
},
{ /* EP 3 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN | AR9170_USB_EP_IRQ,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(64),
.bInterval = 1,
},
{ /* EP 4 */
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT | AR9170_USB_EP_CMD,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = cpu_to_le16(64),
.bInterval = 1,
},
},
};
#ifdef CONFIG_CARL9170FW_USB_MODESWITCH
static void usb_reset_eps(void)
{
unsigned int i;
/* clear all EPs' toggle bit */
for (i = 1; i < __AR9170_USB_NUM_MAX_EP; i++) {
usb_set_input_ep_toggle(i);
usb_clear_input_ep_toggle(i);
}
/*
* NB: I've no idea why this cannot be integrated into the
* previous loop?
*/
for (i = 1; i < __AR9170_USB_NUM_MAX_EP; i++) {
usb_set_output_ep_toggle(i);
usb_clear_output_ep_toggle(i);
}
}
#endif /* CONFIG_CARL9170FW_USB_MODESWITCH */
static void usb_pta_init(void)
{
unsigned int usb_dma_ctrl = 0;
/* Set PTA mode to USB */
andl(AR9170_PTA_REG_DMA_MODE_CTRL,
~AR9170_PTA_DMA_MODE_CTRL_DISABLE_USB);
/* Do a software reset to PTA component */
orl(AR9170_PTA_REG_DMA_MODE_CTRL, AR9170_PTA_DMA_MODE_CTRL_RESET);
andl(AR9170_PTA_REG_DMA_MODE_CTRL, ~AR9170_PTA_DMA_MODE_CTRL_RESET);
if (usb_detect_highspeed()) {
fw.usb.os_cfg_desc = &usb_config_fullspeed;
fw.usb.cfg_desc = &usb_config_highspeed;
/* 512 Byte DMA transfers */
usb_dma_ctrl |= AR9170_USB_DMA_CTL_HIGH_SPEED;
} else {
fw.usb.cfg_desc = &usb_config_fullspeed;
fw.usb.os_cfg_desc = &usb_config_highspeed;
}
#ifdef CONFIG_CARL9170FW_USB_UP_STREAM
# if (CONFIG_CARL9170FW_RX_FRAME_LEN == 4096)
usb_dma_ctrl |= AR9170_USB_DMA_CTL_UP_STREAM_4K;
# elif (CONFIG_CARL9170FW_RX_FRAME_LEN == 8192)
usb_dma_ctrl |= AR9170_USB_DMA_CTL_UP_STREAM_8K;
# elif (CONFIG_CARL9170FW_RX_FRAME_LEN == 16384)
usb_dma_ctrl |= AR9170_USB_DMA_CTL_UP_STREAM_16K;
# elif (CONFIG_CARL9170FW_RX_FRAME_LEN == 32768)
usb_dma_ctrl |= AR9170_USB_DMA_CTL_UP_STREAM_32K;
# else
# error "Invalid AR9170_RX_FRAME_LEN setting"
# endif
#else /* CONFIG_CARL9170FW_USB_UP_STREAM */
usb_dma_ctrl |= AR9170_USB_DMA_CTL_UP_PACKET_MODE;
#endif /* CONFIG_CARL9170FW_USB_UP_STREAM */
#ifdef CONFIG_CARL9170FW_USB_DOWN_STREAM
/* Enable down stream mode */
usb_dma_ctrl |= AR9170_USB_DMA_CTL_DOWN_STREAM;
#endif /* CONFIG_CARL9170FW_USB_DOWN_STREAM */
#ifdef CONFIG_CARL9170FW_USB_UP_STREAM
/* Set the up stream mode maximum aggregate number */
set(AR9170_USB_REG_MAX_AGG_UPLOAD, 4);
/*
* Set the up stream mode timeout value.
* NB: The vendor driver (otus) set 0x80?
*/
set(AR9170_USB_REG_UPLOAD_TIME_CTL, 0x80);
#endif /* CONFIG_CARL9170FW_USB_UP_STREAM */
/* Enable up stream and down stream */
usb_dma_ctrl |= AR9170_USB_DMA_CTL_ENABLE_TO_DEVICE |
AR9170_USB_DMA_CTL_ENABLE_FROM_DEVICE;
set(AR9170_USB_REG_DMA_CTL, usb_dma_ctrl);
}
void usb_init(void)
{
usb_pta_init();
fw.usb.config = 1;
/*
* The fw structure is always initialized with "0"
* during boot(); No need to waste precious bytes here.
*
* fw.usb.interface_setting = 0;
* fw.usb.alternate_interface_setting = 0;
* fw.usb.device_feature = 0;
*/
#ifdef CONFIG_CARL9170FW_WOL
fw.usb.device_feature |= USB_DEVICE_REMOTE_WAKEUP;
usb_enable_remote_wakeup();
#endif /* CONFIG_CARL9170FW_WOL */
}
#define GET_ARRAY(a, o) ((uint32_t *) (((unsigned long) data) + offset))
static void usb_ep0rx_data(const void *data, const unsigned int len)
{
unsigned int offset;
uint32_t value;
BUG_ON(len > AR9170_USB_EP_CTRL_MAX);
BUILD_BUG_ON(len > AR9170_USB_EP_CTRL_MAX);
for (offset = 0; offset < ((len + 3) & ~3); offset += 4) {
value = get(AR9170_USB_REG_EP0_DATA);
memcpy(GET_ARRAY(data, offset), &value,
min(len - offset, (unsigned int)4));
}
}
static int usb_ep0tx_data(const void *data, const unsigned int len)
{
unsigned int offset = 0, block, last_block = 0;
uint32_t value;
BUG_ON(len > AR9170_USB_EP_CTRL_MAX);
BUILD_BUG_ON(len > AR9170_USB_EP_CTRL_MAX);
block = min(len, (unsigned int) 4);
offset = 0;
while (offset < len) {
if (last_block != block || block < 4)
setb(AR9170_USB_REG_FIFO_SIZE, (1 << block) - 1);
memcpy(&value, GET_ARRAY(data, offset), block);
set(AR9170_USB_REG_EP0_DATA, value);
offset += block;
last_block = block = min(len - offset, (unsigned int) 4);
}
setb(AR9170_USB_REG_FIFO_SIZE, 0xf);
/* this will push the data to the host */
return 1;
}
#undef GET_ARRAY
#ifdef CONFIG_CARL9170FW_USB_STANDARD_CMDS
static int usb_get_status(const struct usb_ctrlrequest *ctrl)
{
__le16 status = cpu_to_le16(fw.usb.device_feature);
if ((ctrl->bRequestType & USB_DIR_MASK) != USB_DIR_IN)
return -1;
switch (ctrl->bRequestType & USB_RECIP_MASK) {
case USB_RECIP_DEVICE:
status &= cpu_to_le16(~USB_DEVICE_SELF_POWERED);
status &= cpu_to_le16(~USB_DEVICE_REMOTE_WAKEUP);
break;
case USB_RECIP_INTERFACE:
/* USB spec: This is reserved for future use. */
status = cpu_to_le16(0);
break;
case USB_RECIP_ENDPOINT:
case USB_RECIP_OTHER:
default:
break;
}
return usb_ep0tx_data((const void *) &status, sizeof(status));
}
static int usb_get_string_desc(const struct usb_ctrlrequest *ctrl)
{
const struct usb_string_descriptor *string_desc = NULL;
switch (le16_to_cpu(ctrl->wValue) & 0xff) {
case 0x00:
string_desc = (const struct usb_string_descriptor *)
rom.hw.usb.string0_desc;
break;
case 0x10:
string_desc = (const struct usb_string_descriptor *)
rom.hw.usb.string1_desc;
break;
case 0x20:
string_desc = (const struct usb_string_descriptor *)
rom.hw.usb.string2_desc;
break;
case 0x30:
string_desc = (const struct usb_string_descriptor *)
rom.hw.usb.string3_desc;
break;
default:
break;
}
if (string_desc)
return usb_ep0tx_data(string_desc, string_desc->bLength);
return -1;
}
static int usb_get_device_desc(const struct usb_ctrlrequest *ctrl __unused)
{
return usb_ep0tx_data(&rom.hw.usb.device_desc,
rom.hw.usb.device_desc.bLength);
}
static int usb_get_config_desc(const struct usb_ctrlrequest *ctrl __unused)
{
fw.usb.cfg_desc->cfg.bDescriptorType = USB_DT_CONFIG;
return usb_ep0tx_data(fw.usb.cfg_desc,
le16_to_cpu(fw.usb.cfg_desc->cfg.wTotalLength));
}
#ifdef CONFIG_CARL9170FW_USB_MODESWITCH
static int usb_get_otherspeed_desc(const struct usb_ctrlrequest *ctrl __unused)
{
fw.usb.os_cfg_desc->cfg.bDescriptorType = USB_DT_OTHER_SPEED_CONFIG;
return usb_ep0tx_data(fw.usb.os_cfg_desc,
le16_to_cpu(fw.usb.os_cfg_desc->cfg.wTotalLength));
}
#endif /* CONFIG_CARL9170FW_USB_MODESWITCH */
static int usb_get_qualifier_desc(const struct usb_ctrlrequest *ctrl __unused)
{
struct usb_qualifier_descriptor qual;
/*
* The qualifier descriptor shares some structural details
* with the main device descriptor.
*/
memcpy(&qual, &rom.hw.usb.device_desc, sizeof(qual));
/* (Re)-Initialize fields */
qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
qual.bLength = sizeof(qual);
qual.bNumConfigurations = rom.hw.usb.device_desc.bNumConfigurations;
qual.bRESERVED = 0;
return usb_ep0tx_data(&qual, qual.bLength);
}
#define USB_CHECK_REQTYPE(ctrl, recip, dir) \
(((ctrl->bRequestType & USB_RECIP_MASK) != recip) || \
((ctrl->bRequestType & USB_DIR_MASK) != dir))
static int usb_get_descriptor(const struct usb_ctrlrequest *ctrl)
{
int status = -1;
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_DEVICE, USB_DIR_IN))
return status;
switch (le16_to_cpu(ctrl->wValue) >> 8) {
case USB_DT_DEVICE:
status = usb_get_device_desc(ctrl);
break;
case USB_DT_CONFIG:
status = usb_get_config_desc(ctrl);
break;
case USB_DT_STRING:
status = usb_get_string_desc(ctrl);
break;
case USB_DT_INTERFACE:
break;
case USB_DT_ENDPOINT:
break;
case USB_DT_DEVICE_QUALIFIER:
status = usb_get_qualifier_desc(ctrl);
break;
#ifdef CONFIG_CARL9170FW_USB_MODESWITCH
case USB_DT_OTHER_SPEED_CONFIG:
status = usb_get_otherspeed_desc(ctrl);
break;
#endif /* CONFIG_CARL9170FW_USB_MODESWITCH */
default:
break;
}
return status;
}
static int usb_get_configuration(const struct usb_ctrlrequest *ctrl)
{
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_DEVICE, USB_DIR_IN))
return -1;
return usb_ep0tx_data(&fw.usb.config, 1);
}
static int usb_set_configuration(const struct usb_ctrlrequest *ctrl)
{
unsigned int config;
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_DEVICE, USB_DIR_OUT))
return -1;
config = le16_to_cpu(ctrl->wValue);
switch (config) {
case 0:
/* Disable Device */
andb(AR9170_USB_REG_DEVICE_ADDRESS,
(uint8_t) ~(AR9170_USB_DEVICE_ADDRESS_CONFIGURE));
#ifdef CONFIG_CARL9170FW_USB_MODESWITCH
case 1:
fw.usb.config = config;
if (usb_detect_highspeed()) {
/* High Speed Configuration */
usb_init_highspeed_fifo_cfg();
} else {
/* Full Speed Configuration */
usb_init_fullspeed_fifo_cfg();
}
break;
default:
return -1;
}
/* usb_pta_init() ? */
usb_reset_eps();
orb(AR9170_USB_REG_DEVICE_ADDRESS,
(AR9170_USB_DEVICE_ADDRESS_CONFIGURE));
usb_enable_global_int();
usb_trigger_out();
return 1;
#else
default:
return -1;
}
#endif /* CONFIG_CARL9170FW_USB_MODESWITCH */
}
static int usb_set_address(const struct usb_ctrlrequest *ctrl)
{
unsigned int address;
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_DEVICE, USB_DIR_OUT))
return -1;
address = le16_to_cpu(ctrl->wValue);
/*
* The original firmware used 0x100 (which is, of course,
* too big to fit into uint8_t).
* However based on the available information (hw.h), BIT(7)
* is used as some sort of flag and should not be
* part of the device address.
*/
if (address >= BIT(7))
return -1;
setb(AR9170_USB_REG_DEVICE_ADDRESS, (uint8_t) address);
return 1;
}
static int usb_get_interface(const struct usb_ctrlrequest *ctrl)
{
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_INTERFACE, USB_DIR_IN))
return -1;
if (usb_configured() == false)
return -1;
switch (fw.usb.config) {
case 1:
break;
default:
return -1;
}
return usb_ep0tx_data(&fw.usb.alternate_interface_setting, 1);
}
static int usb_manipulate_feature(const struct usb_ctrlrequest *ctrl, bool __unused clear)
{
unsigned int feature;
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_DEVICE, USB_DIR_OUT))
return -1;
if (usb_configured() == false)
return -1;
feature = le16_to_cpu(ctrl->wValue);
#ifdef CONFIG_CARL9170FW_WOL
if (feature & USB_DEVICE_REMOTE_WAKEUP) {
if (clear)
usb_disable_remote_wakeup();
else
usb_enable_remote_wakeup();
}
#endif /* CONFIG_CARL9170FW_WOL */
if (clear)
fw.usb.device_feature &= ~feature;
else
fw.usb.device_feature |= feature;
return 1;
}
#ifdef CONFIG_CARL9170FW_USB_MODESWITCH
static int usb_set_interface(const struct usb_ctrlrequest *ctrl)
{
unsigned int intf, alt_intf;
if (USB_CHECK_REQTYPE(ctrl, USB_RECIP_INTERFACE, USB_DIR_OUT))
return -1;
if (usb_configured() == false)
return -1;
intf = le16_to_cpu(ctrl->wIndex);
alt_intf = le16_to_cpu(ctrl->wValue);
switch (intf) {
case 0:
if (alt_intf != fw.usb.cfg_desc->intf.bAlternateSetting)
return -1;
fw.usb.interface_setting = (uint8_t) intf;
fw.usb.alternate_interface_setting = (uint8_t) alt_intf;
if (usb_detect_highspeed())
usb_init_highspeed_fifo_cfg();
else
usb_init_fullspeed_fifo_cfg();
usb_reset_eps();
usb_enable_global_int();
usb_trigger_out();
return 1;
default:
return -1;
}
}
#endif /* CONFIG_CARL9170FW_USB_MODESWITCH */
#endif /* CONFIG_CARL9170FW_USB_STANDARD_CMDS */
static int usb_standard_command(const struct usb_ctrlrequest *ctrl __unused)
{
int status = -1;
#ifdef CONFIG_CARL9170FW_USB_STANDARD_CMDS
switch (ctrl->bRequest) {
case USB_REQ_GET_STATUS:
status = usb_get_status(ctrl);
break;
case USB_REQ_CLEAR_FEATURE:
case USB_REQ_SET_FEATURE:
usb_manipulate_feature(ctrl, ctrl->bRequest == USB_REQ_CLEAR_FEATURE);
break;
case USB_REQ_SET_ADDRESS:
status = usb_set_address(ctrl);
break;
case USB_REQ_GET_DESCRIPTOR:
status = usb_get_descriptor(ctrl);
break;
case USB_REQ_SET_DESCRIPTOR:
break;
case USB_REQ_GET_CONFIGURATION:
status = usb_get_configuration(ctrl);
break;
case USB_REQ_SET_CONFIGURATION:
status = usb_set_configuration(ctrl);
break;
case USB_REQ_GET_INTERFACE:
status = usb_get_interface(ctrl);
break;
case USB_REQ_SET_INTERFACE:
#ifdef CONFIG_CARL9170FW_USB_MODESWITCH
status = usb_set_interface(ctrl);
#endif /* CONFIG_CARL9170FW_USB_MODESWITCH */
break;
case USB_REQ_SYNCH_FRAME:
break;
default:
break;
}
#endif /* CONFIG_CARL9170FW_USB_STANDARD_CMDS */
return status;
}
static int usb_class_command(const struct usb_ctrlrequest *ctrl __unused)
{
return -1;
}
static int usb_vendor_command(const struct usb_ctrlrequest *ctrl __unused)
{
/*
* Note: Firmware upload/boot is not implemented.
* It's impossible to replace the current image
* in place.
*/
return -1;
}
#undef USB_CHECK_TYPE
void usb_ep0setup(void)
{
struct usb_ctrlrequest ctrl;
int status = -1;
usb_ep0rx_data(&ctrl, sizeof(ctrl));
switch (ctrl.bRequestType & USB_TYPE_MASK) {
case USB_TYPE_STANDARD:
status = usb_standard_command(&ctrl);
break;
case USB_TYPE_CLASS:
status = usb_class_command(&ctrl);
break;
case USB_TYPE_VENDOR:
status = usb_vendor_command(&ctrl);
break;
default:
break;
}
if (status < 0)
fw.usb.ep0_action |= CARL9170_EP0_STALL;
#ifdef CONFIG_CARL9170FW_USB_STANDARD_CMDS
if (status > 0)
fw.usb.ep0_action |= CARL9170_EP0_TRIGGER;
#endif /* CONFIG_CARL9170FW_USB_STANDARD_CMDS */
}
void usb_ep0rx(void)
{
if (BUG_ON(!fw.usb.ep0_txrx_buffer || !fw.usb.ep0_txrx_len))
return ;
usb_ep0rx_data(fw.usb.ep0_txrx_buffer, fw.usb.ep0_txrx_len);
fw.usb.ep0_txrx_pos = fw.usb.ep0_txrx_len;
}
void usb_ep0tx(void)
{
if (BUG_ON(!fw.usb.ep0_txrx_buffer || !fw.usb.ep0_txrx_len))
return ;
usb_ep0tx_data(fw.usb.ep0_txrx_buffer, fw.usb.ep0_txrx_len);
fw.usb.ep0_txrx_pos = fw.usb.ep0_txrx_len;
}