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android_kernel_xiaomi_sm8350/drivers/usb/input/appletouch.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers 
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

643 lines
17 KiB
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/*
* Apple USB Touchpad (for post-February 2005 PowerBooks and MacBooks) driver
*
* Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2005 Johannes Berg (johannes@sipsolutions.net)
* Copyright (C) 2005 Stelian Pop (stelian@popies.net)
* Copyright (C) 2005 Frank Arnold (frank@scirocco-5v-turbo.de)
* Copyright (C) 2005 Peter Osterlund (petero2@telia.com)
* Copyright (C) 2005 Michael Hanselmann (linux-kernel@hansmi.ch)
* Copyright (C) 2006 Nicolas Boichat (nicolas@boichat.ch)
*
* Thanks to Alex Harper <basilisk@foobox.net> for his inputs.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/usb/input.h>
/* Apple has powerbooks which have the keyboard with different Product IDs */
#define APPLE_VENDOR_ID 0x05AC
/* These names come from Info.plist in AppleUSBTrackpad.kext */
#define GEYSER_ANSI_PRODUCT_ID 0x0214
#define GEYSER_ISO_PRODUCT_ID 0x0215
#define GEYSER_JIS_PRODUCT_ID 0x0216
/* MacBook devices */
#define GEYSER3_ANSI_PRODUCT_ID 0x0217
#define GEYSER3_ISO_PRODUCT_ID 0x0218
#define GEYSER3_JIS_PRODUCT_ID 0x0219
#define ATP_DEVICE(prod) \
.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
USB_DEVICE_ID_MATCH_INT_CLASS | \
USB_DEVICE_ID_MATCH_INT_PROTOCOL, \
.idVendor = APPLE_VENDOR_ID, \
.idProduct = (prod), \
.bInterfaceClass = 0x03, \
.bInterfaceProtocol = 0x02
/* table of devices that work with this driver */
static struct usb_device_id atp_table [] = {
{ ATP_DEVICE(0x020E) },
{ ATP_DEVICE(0x020F) },
{ ATP_DEVICE(0x030A) },
{ ATP_DEVICE(0x030B) },
/* PowerBooks Oct 2005 */
{ ATP_DEVICE(GEYSER_ANSI_PRODUCT_ID) },
{ ATP_DEVICE(GEYSER_ISO_PRODUCT_ID) },
{ ATP_DEVICE(GEYSER_JIS_PRODUCT_ID) },
{ ATP_DEVICE(GEYSER3_ANSI_PRODUCT_ID) },
{ ATP_DEVICE(GEYSER3_ISO_PRODUCT_ID) },
{ ATP_DEVICE(GEYSER3_JIS_PRODUCT_ID) },
/* Terminating entry */
{ }
};
MODULE_DEVICE_TABLE (usb, atp_table);
/*
* number of sensors. Note that only 16 instead of 26 X (horizontal)
* sensors exist on 12" and 15" PowerBooks. All models have 16 Y
* (vertical) sensors.
*/
#define ATP_XSENSORS 26
#define ATP_YSENSORS 16
/* amount of fuzz this touchpad generates */
#define ATP_FUZZ 16
/* maximum pressure this driver will report */
#define ATP_PRESSURE 300
/*
* multiplication factor for the X and Y coordinates.
* We try to keep the touchpad aspect ratio while still doing only simple
* arithmetics.
* The factors below give coordinates like:
* 0 <= x < 960 on 12" and 15" Powerbooks
* 0 <= x < 1600 on 17" Powerbooks
* 0 <= y < 646
*/
#define ATP_XFACT 64
#define ATP_YFACT 43
/*
* Threshold for the touchpad sensors. Any change less than ATP_THRESHOLD is
* ignored.
*/
#define ATP_THRESHOLD 5
/* MacBook Pro (Geyser 3) initialization constants */
#define ATP_GEYSER3_MODE_READ_REQUEST_ID 1
#define ATP_GEYSER3_MODE_WRITE_REQUEST_ID 9
#define ATP_GEYSER3_MODE_REQUEST_VALUE 0x300
#define ATP_GEYSER3_MODE_REQUEST_INDEX 0
#define ATP_GEYSER3_MODE_VENDOR_VALUE 0x04
/* Structure to hold all of our device specific stuff */
struct atp {
char phys[64];
struct usb_device * udev; /* usb device */
struct urb * urb; /* usb request block */
signed char * data; /* transferred data */
int open; /* non-zero if opened */
struct input_dev *input; /* input dev */
int valid; /* are the sensors valid ? */
int x_old; /* last reported x/y, */
int y_old; /* used for smoothing */
/* current value of the sensors */
signed char xy_cur[ATP_XSENSORS + ATP_YSENSORS];
/* last value of the sensors */
signed char xy_old[ATP_XSENSORS + ATP_YSENSORS];
/* accumulated sensors */
int xy_acc[ATP_XSENSORS + ATP_YSENSORS];
int overflowwarn; /* overflow warning printed? */
int datalen; /* size of an USB urb transfer */
};
#define dbg_dump(msg, tab) \
if (debug > 1) { \
int i; \
printk("appletouch: %s %lld", msg, (long long)jiffies); \
for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) \
printk(" %02x", tab[i]); \
printk("\n"); \
}
#define dprintk(format, a...) \
do { \
if (debug) printk(format, ##a); \
} while (0)
MODULE_AUTHOR("Johannes Berg, Stelian Pop, Frank Arnold, Michael Hanselmann");
MODULE_DESCRIPTION("Apple PowerBooks USB touchpad driver");
MODULE_LICENSE("GPL");
static int debug = 1;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Activate debugging output");
/* Checks if the device a Geyser 2 (ANSI, ISO, JIS) */
static inline int atp_is_geyser_2(struct atp *dev)
{
u16 productId = le16_to_cpu(dev->udev->descriptor.idProduct);
return (productId == GEYSER_ANSI_PRODUCT_ID) ||
(productId == GEYSER_ISO_PRODUCT_ID) ||
(productId == GEYSER_JIS_PRODUCT_ID);
}
static inline int atp_is_geyser_3(struct atp *dev)
{
u16 productId = le16_to_cpu(dev->udev->descriptor.idProduct);
return (productId == GEYSER3_ANSI_PRODUCT_ID) ||
(productId == GEYSER3_ISO_PRODUCT_ID) ||
(productId == GEYSER3_JIS_PRODUCT_ID);
}
static int atp_calculate_abs(int *xy_sensors, int nb_sensors, int fact,
int *z, int *fingers)
{
int i;
/* values to calculate mean */
int pcum = 0, psum = 0;
*fingers = 0;
for (i = 0; i < nb_sensors; i++) {
if (xy_sensors[i] < ATP_THRESHOLD)
continue;
if ((i - 1 < 0) || (xy_sensors[i - 1] < ATP_THRESHOLD))
(*fingers)++;
pcum += xy_sensors[i] * i;
psum += xy_sensors[i];
}
if (psum > 0) {
*z = psum;
return pcum * fact / psum;
}
return 0;
}
static inline void atp_report_fingers(struct input_dev *input, int fingers)
{
input_report_key(input, BTN_TOOL_FINGER, fingers == 1);
input_report_key(input, BTN_TOOL_DOUBLETAP, fingers == 2);
input_report_key(input, BTN_TOOL_TRIPLETAP, fingers > 2);
}
static void atp_complete(struct urb* urb)
{
int x, y, x_z, y_z, x_f, y_f;
int retval, i, j;
struct atp *dev = urb->context;
switch (urb->status) {
case 0:
/* success */
break;
case -EOVERFLOW:
if(!dev->overflowwarn) {
printk("appletouch: OVERFLOW with data "
"length %d, actual length is %d\n",
dev->datalen, dev->urb->actual_length);
dev->overflowwarn = 1;
}
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* This urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d",
__FUNCTION__, urb->status);
return;
default:
dbg("%s - nonzero urb status received: %d",
__FUNCTION__, urb->status);
goto exit;
}
/* drop incomplete datasets */
if (dev->urb->actual_length != dev->datalen) {
dprintk("appletouch: incomplete data package"
" (first byte: %d, length: %d).\n",
dev->data[0], dev->urb->actual_length);
goto exit;
}
/* reorder the sensors values */
if (atp_is_geyser_3(dev)) {
memset(dev->xy_cur, 0, sizeof(dev->xy_cur));
/*
* The values are laid out like this:
* -, Y1, Y2, -, Y3, Y4, -, ..., -, X1, X2, -, X3, X4, ...
* '-' is an unused value.
*/
/* read X values */
for (i = 0, j = 19; i < 20; i += 2, j += 3) {
dev->xy_cur[i] = dev->data[j + 1];
dev->xy_cur[i + 1] = dev->data[j + 2];
}
/* read Y values */
for (i = 0, j = 1; i < 9; i += 2, j += 3) {
dev->xy_cur[ATP_XSENSORS + i] = dev->data[j + 1];
dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 2];
}
} else if (atp_is_geyser_2(dev)) {
memset(dev->xy_cur, 0, sizeof(dev->xy_cur));
/*
* The values are laid out like this:
* Y1, Y2, -, Y3, Y4, -, ..., X1, X2, -, X3, X4, -, ...
* '-' is an unused value.
*/
/* read X values */
for (i = 0, j = 19; i < 20; i += 2, j += 3) {
dev->xy_cur[i] = dev->data[j];
dev->xy_cur[i + 1] = dev->data[j + 1];
}
/* read Y values */
for (i = 0, j = 1; i < 9; i += 2, j += 3) {
dev->xy_cur[ATP_XSENSORS + i] = dev->data[j];
dev->xy_cur[ATP_XSENSORS + i + 1] = dev->data[j + 1];
}
} else {
for (i = 0; i < 8; i++) {
/* X values */
dev->xy_cur[i ] = dev->data[5 * i + 2];
dev->xy_cur[i + 8] = dev->data[5 * i + 4];
dev->xy_cur[i + 16] = dev->data[5 * i + 42];
if (i < 2)
dev->xy_cur[i + 24] = dev->data[5 * i + 44];
/* Y values */
dev->xy_cur[i + 26] = dev->data[5 * i + 1];
dev->xy_cur[i + 34] = dev->data[5 * i + 3];
}
}
dbg_dump("sample", dev->xy_cur);
if (!dev->valid) {
/* first sample */
dev->valid = 1;
dev->x_old = dev->y_old = -1;
memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
if (atp_is_geyser_3(dev)) /* No 17" Macbooks (yet) */
goto exit;
/* 17" Powerbooks have extra X sensors */
for (i = (atp_is_geyser_2(dev)?15:16); i < ATP_XSENSORS; i++) {
if (!dev->xy_cur[i]) continue;
printk("appletouch: 17\" model detected.\n");
if(atp_is_geyser_2(dev))
input_set_abs_params(dev->input, ABS_X, 0,
(20 - 1) *
ATP_XFACT - 1,
ATP_FUZZ, 0);
else
input_set_abs_params(dev->input, ABS_X, 0,
(ATP_XSENSORS - 1) *
ATP_XFACT - 1,
ATP_FUZZ, 0);
break;
}
goto exit;
}
for (i = 0; i < ATP_XSENSORS + ATP_YSENSORS; i++) {
/* accumulate the change */
signed char change = dev->xy_old[i] - dev->xy_cur[i];
dev->xy_acc[i] -= change;
/* prevent down drifting */
if (dev->xy_acc[i] < 0)
dev->xy_acc[i] = 0;
}
memcpy(dev->xy_old, dev->xy_cur, sizeof(dev->xy_old));
dbg_dump("accumulator", dev->xy_acc);
x = atp_calculate_abs(dev->xy_acc, ATP_XSENSORS,
ATP_XFACT, &x_z, &x_f);
y = atp_calculate_abs(dev->xy_acc + ATP_XSENSORS, ATP_YSENSORS,
ATP_YFACT, &y_z, &y_f);
if (x && y) {
if (dev->x_old != -1) {
x = (dev->x_old * 3 + x) >> 2;
y = (dev->y_old * 3 + y) >> 2;
dev->x_old = x;
dev->y_old = y;
if (debug > 1)
printk("appletouch: X: %3d Y: %3d "
"Xz: %3d Yz: %3d\n",
x, y, x_z, y_z);
input_report_key(dev->input, BTN_TOUCH, 1);
input_report_abs(dev->input, ABS_X, x);
input_report_abs(dev->input, ABS_Y, y);
input_report_abs(dev->input, ABS_PRESSURE,
min(ATP_PRESSURE, x_z + y_z));
atp_report_fingers(dev->input, max(x_f, y_f));
}
dev->x_old = x;
dev->y_old = y;
}
else if (!x && !y) {
dev->x_old = dev->y_old = -1;
input_report_key(dev->input, BTN_TOUCH, 0);
input_report_abs(dev->input, ABS_PRESSURE, 0);
atp_report_fingers(dev->input, 0);
/* reset the accumulator on release */
memset(dev->xy_acc, 0, sizeof(dev->xy_acc));
}
input_report_key(dev->input, BTN_LEFT,
!!dev->data[dev->datalen - 1]);
input_sync(dev->input);
exit:
retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
if (retval) {
err("%s - usb_submit_urb failed with result %d",
__FUNCTION__, retval);
}
}
static int atp_open(struct input_dev *input)
{
struct atp *dev = input->private;
if (usb_submit_urb(dev->urb, GFP_ATOMIC))
return -EIO;
dev->open = 1;
return 0;
}
static void atp_close(struct input_dev *input)
{
struct atp *dev = input->private;
usb_kill_urb(dev->urb);
dev->open = 0;
}
static int atp_probe(struct usb_interface *iface, const struct usb_device_id *id)
{
struct atp *dev;
struct input_dev *input_dev;
struct usb_device *udev = interface_to_usbdev(iface);
struct usb_host_interface *iface_desc;
struct usb_endpoint_descriptor *endpoint;
int int_in_endpointAddr = 0;
int i, retval = -ENOMEM;
/* set up the endpoint information */
/* use only the first interrupt-in endpoint */
iface_desc = iface->cur_altsetting;
for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
endpoint = &iface_desc->endpoint[i].desc;
if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
/* we found an interrupt in endpoint */
int_in_endpointAddr = endpoint->bEndpointAddress;
break;
}
}
if (!int_in_endpointAddr) {
err("Could not find int-in endpoint");
return -EIO;
}
/* allocate memory for our device state and initialize it */
dev = kzalloc(sizeof(struct atp), GFP_KERNEL);
input_dev = input_allocate_device();
if (!dev || !input_dev) {
err("Out of memory");
goto err_free_devs;
}
dev->udev = udev;
dev->input = input_dev;
dev->overflowwarn = 0;
if (atp_is_geyser_3(dev))
dev->datalen = 64;
else if (atp_is_geyser_2(dev))
dev->datalen = 64;
else
dev->datalen = 81;
if (atp_is_geyser_3(dev)) {
/*
* By default Geyser 3 device sends standard USB HID mouse
* packets (Report ID 2). This code changes device mode, so it
* sends raw sensor reports (Report ID 5).
*/
char data[8];
int size;
size = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
ATP_GEYSER3_MODE_READ_REQUEST_ID,
USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
ATP_GEYSER3_MODE_REQUEST_VALUE,
ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
if (size != 8) {
err("Could not do mode read request from device"
" (Geyser 3 mode)");
goto err_free_devs;
}
/* Apply the mode switch */
data[0] = ATP_GEYSER3_MODE_VENDOR_VALUE;
size = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
ATP_GEYSER3_MODE_WRITE_REQUEST_ID,
USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
ATP_GEYSER3_MODE_REQUEST_VALUE,
ATP_GEYSER3_MODE_REQUEST_INDEX, &data, 8, 5000);
if (size != 8) {
err("Could not do mode write request to device"
" (Geyser 3 mode)");
goto err_free_devs;
}
printk("appletouch Geyser 3 inited.\n");
}
dev->urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->urb) {
retval = -ENOMEM;
goto err_free_devs;
}
dev->data = usb_buffer_alloc(dev->udev, dev->datalen, GFP_KERNEL,
&dev->urb->transfer_dma);
if (!dev->data) {
retval = -ENOMEM;
goto err_free_urb;
}
usb_fill_int_urb(dev->urb, udev,
usb_rcvintpipe(udev, int_in_endpointAddr),
dev->data, dev->datalen, atp_complete, dev, 1);
usb_make_path(udev, dev->phys, sizeof(dev->phys));
strlcat(dev->phys, "/input0", sizeof(dev->phys));
input_dev->name = "appletouch";
input_dev->phys = dev->phys;
usb_to_input_id(dev->udev, &input_dev->id);
input_dev->cdev.dev = &iface->dev;
input_dev->private = dev;
input_dev->open = atp_open;
input_dev->close = atp_close;
set_bit(EV_ABS, input_dev->evbit);
if (atp_is_geyser_3(dev)) {
/*
* MacBook have 20 X sensors, 10 Y sensors
*/
input_set_abs_params(input_dev, ABS_X, 0,
((20 - 1) * ATP_XFACT) - 1, ATP_FUZZ, 0);
input_set_abs_params(input_dev, ABS_Y, 0,
((10 - 1) * ATP_YFACT) - 1, ATP_FUZZ, 0);
} else if (atp_is_geyser_2(dev)) {
/*
* Oct 2005 15" PowerBooks have 15 X sensors, 17" are detected
* later.
*/
input_set_abs_params(input_dev, ABS_X, 0,
((15 - 1) * ATP_XFACT) - 1, ATP_FUZZ, 0);
input_set_abs_params(input_dev, ABS_Y, 0,
((9 - 1) * ATP_YFACT) - 1, ATP_FUZZ, 0);
} else {
/*
* 12" and 15" Powerbooks only have 16 x sensors,
* 17" models are detected later.
*/
input_set_abs_params(input_dev, ABS_X, 0,
(16 - 1) * ATP_XFACT - 1, ATP_FUZZ, 0);
input_set_abs_params(input_dev, ABS_Y, 0,
(ATP_YSENSORS - 1) * ATP_YFACT - 1, ATP_FUZZ, 0);
}
input_set_abs_params(input_dev, ABS_PRESSURE, 0, ATP_PRESSURE, 0, 0);
set_bit(EV_KEY, input_dev->evbit);
set_bit(BTN_TOUCH, input_dev->keybit);
set_bit(BTN_TOOL_FINGER, input_dev->keybit);
set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
set_bit(BTN_LEFT, input_dev->keybit);
input_register_device(dev->input);
/* save our data pointer in this interface device */
usb_set_intfdata(iface, dev);
return 0;
err_free_urb:
usb_free_urb(dev->urb);
err_free_devs:
usb_set_intfdata(iface, NULL);
kfree(dev);
input_free_device(input_dev);
return retval;
}
static void atp_disconnect(struct usb_interface *iface)
{
struct atp *dev = usb_get_intfdata(iface);
usb_set_intfdata(iface, NULL);
if (dev) {
usb_kill_urb(dev->urb);
input_unregister_device(dev->input);
usb_buffer_free(dev->udev, dev->datalen,
dev->data, dev->urb->transfer_dma);
usb_free_urb(dev->urb);
kfree(dev);
}
printk(KERN_INFO "input: appletouch disconnected\n");
}
static int atp_suspend(struct usb_interface *iface, pm_message_t message)
{
struct atp *dev = usb_get_intfdata(iface);
usb_kill_urb(dev->urb);
dev->valid = 0;
return 0;
}
static int atp_resume(struct usb_interface *iface)
{
struct atp *dev = usb_get_intfdata(iface);
if (dev->open && usb_submit_urb(dev->urb, GFP_ATOMIC))
return -EIO;
return 0;
}
static struct usb_driver atp_driver = {
.name = "appletouch",
.probe = atp_probe,
.disconnect = atp_disconnect,
.suspend = atp_suspend,
.resume = atp_resume,
.id_table = atp_table,
};
static int __init atp_init(void)
{
return usb_register(&atp_driver);
}
static void __exit atp_exit(void)
{
usb_deregister(&atp_driver);
}
module_init(atp_init);
module_exit(atp_exit);
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