From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751436AbdE3Mu0 (ORCPT ); Tue, 30 May 2017 08:50:26 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:35035 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750898AbdE3MuY (ORCPT ); Tue, 30 May 2017 08:50:24 -0400 Subject: Re: [PATCH 2/2] xen/input: add multi-touch support To: Dmitry Torokhov References: <1492083484-31786-1-git-send-email-andr2000@gmail.com> <1492083484-31786-3-git-send-email-andr2000@gmail.com> <20170421021018.GB23279@dtor-ws> <20170530055150.GA38163@dtor-ws> Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, joculator@gmail.com, al1img@gmail.com, vlad.babchuk@gmail.com, andrii.anisov@gmail.com, olekstysh@gmail.com, boris.ostrovsky@oracle.com, jgross@suse.com, Oleksandr Andrushchenko From: Oleksandr Andrushchenko Message-ID: <8092dd49-20e0-3e8d-977d-2f570142a37d@gmail.com> Date: Tue, 30 May 2017 15:50:20 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170530055150.GA38163@dtor-ws> Content-Type: multipart/mixed; boundary="------------732AA74FE6E43547D6855880" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------732AA74FE6E43547D6855880 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Hi, Dmitry! On 05/30/2017 08:51 AM, Dmitry Torokhov wrote: > On Fri, Apr 21, 2017 at 09:40:36AM +0300, Oleksandr Andrushchenko wrote: >> Hi, Dmitry! >> >> On 04/21/2017 05:10 AM, Dmitry Torokhov wrote: >>> Hi Oleksandr, >>> >>> On Thu, Apr 13, 2017 at 02:38:04PM +0300, Oleksandr Andrushchenko wrote: >>>> From: Oleksandr Andrushchenko >>>> >>>> Extend xen_kbdfront to provide multi-touch support >>>> to unprivileged domains. >>>> >>>> Signed-off-by: Oleksandr Andrushchenko >>>> --- >>>> drivers/input/misc/xen-kbdfront.c | 142 +++++++++++++++++++++++++++++++++++++- >>>> 1 file changed, 140 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c >>>> index 01c27b4c3288..e5d064aaa237 100644 >>>> --- a/drivers/input/misc/xen-kbdfront.c >>>> +++ b/drivers/input/misc/xen-kbdfront.c >>>> @@ -17,6 +17,7 @@ >>>> #include >>>> #include >>>> #include >>>> +#include >>>> #include >>>> #include >>>> @@ -34,11 +35,14 @@ >>>> struct xenkbd_info { >>>> struct input_dev *kbd; >>>> struct input_dev *ptr; >>>> + struct input_dev *mtouch; >>>> struct xenkbd_page *page; >>>> int gref; >>>> int irq; >>>> struct xenbus_device *xbdev; >>>> char phys[32]; >>>> + /* current MT slot/contact ID we are injecting events in */ >>>> + int mtouch_cur_contact_id; >>>> }; >>>> enum { KPARAM_X, KPARAM_Y, KPARAM_CNT }; >>>> @@ -47,6 +51,12 @@ module_param_array(ptr_size, int, NULL, 0444); >>>> MODULE_PARM_DESC(ptr_size, >>>> "Pointing device width, height in pixels (default 800,600)"); >>>> +enum { KPARAM_MT_X, KPARAM_MT_Y, KPARAM_MT_CNT }; >>>> +static int mtouch_size[KPARAM_MT_CNT] = { XENFB_WIDTH, XENFB_HEIGHT }; >>>> +module_param_array(mtouch_size, int, NULL, 0444); >>>> +MODULE_PARM_DESC(ptr_size, >>>> + "Multi-touch device width, height in pixels (default 800,600)"); >>>> + >>> Why do you need separate module parameters for multi-touch device? >> please see below >>>> static int xenkbd_remove(struct xenbus_device *); >>>> static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *); >>>> static void xenkbd_disconnect_backend(struct xenkbd_info *); >>>> @@ -100,6 +110,60 @@ static irqreturn_t input_handler(int rq, void *dev_id) >>>> input_report_rel(dev, REL_WHEEL, >>>> -event->pos.rel_z); >>>> break; >>>> + case XENKBD_TYPE_MTOUCH: >>>> + dev = info->mtouch; >>>> + if (unlikely(!dev)) >>>> + break; >>>> + if (unlikely(event->mtouch.contact_id != >>>> + info->mtouch_cur_contact_id)) { >>> Why is this unlikely? Does contact ID changes once in 1000 packets or >>> even less? >> Mu assumption was that regardless of the fact that we are multi-touch >> device still single touches will come in more frequently >> But I can remove *unlikely* if my assumption is not correct > I think the normal expectation is that "unlikely" is supposed for > something that happens once in a blue moon, so I'd rather remove it. > agree, removed "unlikely" >>>> + info->mtouch_cur_contact_id = >>>> + event->mtouch.contact_id; >>>> + input_mt_slot(dev, event->mtouch.contact_id); >>>> + } >>>> + switch (event->mtouch.event_type) { >>>> + case XENKBD_MT_EV_DOWN: >>>> + input_mt_report_slot_state(dev, MT_TOOL_FINGER, >>>> + true); > Should we establish tool event? We have MT_TOOL_PEN, etc. I think that for multi-touch MT_TOOL_FINGER is enough any reason we would also want MT_TOOL_PEN here? (I guess MT_TOOL_PALM is not appropriate anyways) >>>> + input_event(dev, EV_ABS, ABS_MT_POSITION_X, >>>> + event->mtouch.u.pos.abs_x); >>>> + input_event(dev, EV_ABS, ABS_MT_POSITION_Y, >>>> + event->mtouch.u.pos.abs_y); >>>> + input_event(dev, EV_ABS, ABS_X, >>>> + event->mtouch.u.pos.abs_x); >>>> + input_event(dev, EV_ABS, ABS_Y, >>>> + event->mtouch.u.pos.abs_y); >>>> + break; >>>> + case XENKBD_MT_EV_UP: >>>> + input_mt_report_slot_state(dev, MT_TOOL_FINGER, >>>> + false); >>>> + break; >>>> + case XENKBD_MT_EV_MOTION: >>>> + input_event(dev, EV_ABS, ABS_MT_POSITION_X, >>>> + event->mtouch.u.pos.abs_x); >>>> + input_event(dev, EV_ABS, ABS_MT_POSITION_Y, >>>> + event->mtouch.u.pos.abs_y); >>>> + input_event(dev, EV_ABS, ABS_X, >>>> + event->mtouch.u.pos.abs_x); >>>> + input_event(dev, EV_ABS, ABS_Y, >>>> + event->mtouch.u.pos.abs_y); >>>> + break; >>>> + case XENKBD_MT_EV_SYN: >>>> + input_mt_sync_frame(dev); >>>> + break; >>>> + case XENKBD_MT_EV_SHAPE: >>>> + input_event(dev, EV_ABS, ABS_MT_TOUCH_MAJOR, >>>> + event->mtouch.u.shape.major); >>>> + input_event(dev, EV_ABS, ABS_MT_TOUCH_MINOR, >>>> + event->mtouch.u.shape.minor); >>>> + break; >>>> + case XENKBD_MT_EV_ORIENT: >>>> + input_event(dev, EV_ABS, ABS_MT_ORIENTATION, >>>> + event->mtouch.u.orientation); >>>> + break; >>>> + } >>>> + /* only report syn when requested */ >>>> + if (event->mtouch.event_type != XENKBD_MT_EV_SYN) >>>> + dev = NULL; >>>> } >>>> if (dev) >>>> input_sync(dev); >>>> @@ -115,9 +179,9 @@ static int xenkbd_probe(struct xenbus_device *dev, >>>> const struct xenbus_device_id *id) >>>> { >>>> int ret, i; >>>> - unsigned int abs; >>>> + unsigned int abs, touch; >>>> struct xenkbd_info *info; >>>> - struct input_dev *kbd, *ptr; >>>> + struct input_dev *kbd, *ptr, *mtouch; >>>> info = kzalloc(sizeof(*info), GFP_KERNEL); >>>> if (!info) { >>>> @@ -152,6 +216,17 @@ static int xenkbd_probe(struct xenbus_device *dev, >>>> } >>>> } >>>> + touch = xenbus_read_unsigned(dev->nodename, >>>> + XENKBD_FIELD_FEAT_MTOUCH, 0); >>>> + if (touch) { >>>> + ret = xenbus_write(XBT_NIL, dev->nodename, >>>> + XENKBD_FIELD_REQ_MTOUCH, "1"); >>>> + if (ret) { >>>> + pr_warning("xenkbd: can't request multi-touch"); >>>> + touch = 0; >>>> + } >>>> + } >>>> + >>>> /* keyboard */ >>>> kbd = input_allocate_device(); >>>> if (!kbd) >>>> @@ -208,6 +283,67 @@ static int xenkbd_probe(struct xenbus_device *dev, >>>> } >>>> info->ptr = ptr; >>>> + /* multi-touch device */ >>>> + if (touch) { >>>> + int num_cont, width, height; >>>> + >>>> + mtouch = input_allocate_device(); >>>> + if (!mtouch) >>>> + goto error_nomem; >>>> + >>>> + num_cont = xenbus_read_unsigned(info->xbdev->nodename, >>>> + XENKBD_FIELD_MT_NUM_CONTACTS, >>>> + 1); > Should we refuse MT devices with number of contacts less than 2? we can, but I see no harm in 1. what is more, this may allow guests to emulate more pointing devices but, if you insist, then I will add appropriate code to reject if number of contacts is less then 2 >>>> + width = xenbus_read_unsigned(info->xbdev->nodename, >>>> + XENKBD_FIELD_MT_WIDTH, >>>> + XENFB_WIDTH); >>>> + height = xenbus_read_unsigned(info->xbdev->nodename, >>>> + XENKBD_FIELD_MT_HEIGHT, >>>> + XENFB_HEIGHT); >>> Curious why you need separate parameters here too... >> This is because mt parameters are different from ptr >> in a way that they are configurable per front driver's >> instance rather than per backend, e.g. in XenStore: >> >> /local/domain/0/backend/vkbd/1/0/width = "1920" >> /local/domain/0/backend/vkbd/1/0/height = "1080" >> >> /local/domain/1/device/vkbd/0/multi-touch-width = "1920" >> /local/domain/1/device/vkbd/0/multi-touch-height = "1080" >> /local/domain/1/device/vkbd/0/multi-touch-num-contacts = "10" >> >> /local/domain/1/device/vkbd/1/multi-touch-width = "800" >> /local/domain/1/device/vkbd/1/multi-touch-height = "600" >> /local/domain/1/device/vkbd/1/multi-touch-num-contacts = "3" >> >> The main reason for such configuration is that you can >> configure multiple mt input devices even for the same guest >> with different resolutions which may not match those >> configured for ptr. >> (In my use-case I use new displif protocol [1] in conjunction >> with mt input devices and the corresponding backend is not >> QEMU's xenfb) > I see. > >> As to module parameters, I added those to be consistent with >> ptr device. Do you think we can live without them and >> do you want me to remove them? > Yes, I think we better. I am also confused by the way you are handling > the module parameters. It looks to me you update them with data passed > from the backend, but never use the data... I have removed module parameters (the only use of those was to be able to see configured width and height on guest side, but this is minor) >>>> + >>>> + mtouch->name = "Xen Virtual Multi-touch"; >>>> + mtouch->phys = info->phys; >>>> + mtouch->id.bustype = BUS_PCI; >>>> + mtouch->id.vendor = 0x5853; >>>> + mtouch->id.product = 0xfffd; >>>> + >>>> + __set_bit(EV_ABS, mtouch->evbit); >>>> + __set_bit(EV_KEY, mtouch->evbit); >>>> + __set_bit(BTN_TOUCH, mtouch->keybit); >>>> + >>>> + input_set_abs_params(mtouch, ABS_X, >>>> + 0, width, 0, 0); >>>> + input_set_abs_params(mtouch, ABS_Y, >>>> + 0, height, 0, 0); >>>> + input_set_abs_params(mtouch, ABS_PRESSURE, >>>> + 0, 255, 0, 0); >>>> + >>>> + input_set_abs_params(mtouch, ABS_MT_TOUCH_MAJOR, >>>> + 0, 255, 0, 0); >>>> + input_set_abs_params(mtouch, ABS_MT_POSITION_X, >>>> + 0, width, 0, 0); >>>> + input_set_abs_params(mtouch, ABS_MT_POSITION_Y, >>>> + 0, height, 0, 0); >>>> + input_set_abs_params(mtouch, ABS_MT_PRESSURE, >>>> + 0, 255, 0, 0); >>>> + >>>> + input_mt_init_slots(mtouch, num_cont, 0); > We need error handling here. done > Also, it would be nice if we set INPUT_MT_* > flags here, so that userspace had better chance of figuring how to > handle the device. done, I will use INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED >>>> + >>>> + mtouch_size[KPARAM_MT_X] = width; >>>> + mtouch_size[KPARAM_MT_Y] = height; >>>> + info->mtouch_cur_contact_id = -1; >>>> + >>>> + ret = input_register_device(mtouch); >>>> + if (ret) { >>>> + input_free_device(mtouch); >>>> + xenbus_dev_fatal(info->xbdev, ret, >>>> + "input_register_device(mtouch)"); >>>> + goto error; >>>> + } >>>> + info->mtouch_cur_contact_id = -1; >>>> + info->mtouch = mtouch; >>>> + } >>>> + >>>> ret = xenkbd_connect_backend(dev, info); >>>> if (ret < 0) >>>> goto error; >>>> @@ -240,6 +376,8 @@ static int xenkbd_remove(struct xenbus_device *dev) >>>> input_unregister_device(info->kbd); >>>> if (info->ptr) >>>> input_unregister_device(info->ptr); >>>> + if (info->mtouch) >>>> + input_unregister_device(info->mtouch); >>>> free_page((unsigned long)info->page); >>>> kfree(info); >>>> return 0; >>>> -- >>>> 2.7.4 >>>> > > Thanks. > For your convenience I am attaching the changes I am about to put into v1 of the series: - remove unlikely - remove module parameters - error handling for input_mt_init_slots - let userspace better chance of figuring how to handle the device Thank you, Oleksandr --------------732AA74FE6E43547D6855880 Content-Type: text/x-patch; name="mtouch_v0_review_fixes.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="mtouch_v0_review_fixes.patch" >>From e76506c55846e2bb4ccbafa430642e368643e51d Mon Sep 17 00:00:00 2001 From: Oleksandr Andrushchenko Date: Tue, 30 May 2017 14:49:58 +0300 Subject: [PATCH] Fix: remove unlikely Fix: remove module paramters Fix: error handling for input_mt_init_slots Fix: let userspace better chance of figuring how to handle the device Signed-off-by: Oleksandr Andrushchenko --- drivers/input/misc/xen-kbdfront.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c index 8266ef948a06..273d786a19cd 100644 --- a/drivers/input/misc/xen-kbdfront.c +++ b/drivers/input/misc/xen-kbdfront.c @@ -51,12 +51,6 @@ module_param_array(ptr_size, int, NULL, 0444); MODULE_PARM_DESC(ptr_size, "Pointing device width, height in pixels (default 800,600)"); -enum { KPARAM_MT_X, KPARAM_MT_Y, KPARAM_MT_CNT }; -static int mtouch_size[KPARAM_MT_CNT] = { XENFB_WIDTH, XENFB_HEIGHT }; -module_param_array(mtouch_size, int, NULL, 0444); -MODULE_PARM_DESC(ptr_size, - "Multi-touch device width, height in pixels (default 800,600)"); - static int xenkbd_remove(struct xenbus_device *); static int xenkbd_connect_backend(struct xenbus_device *, struct xenkbd_info *); static void xenkbd_disconnect_backend(struct xenkbd_info *); @@ -114,8 +108,8 @@ static irqreturn_t input_handler(int rq, void *dev_id) dev = info->mtouch; if (unlikely(!dev)) break; - if (unlikely(event->mtouch.contact_id != - info->mtouch_cur_contact_id)) { + if (event->mtouch.contact_id != + info->mtouch_cur_contact_id) { info->mtouch_cur_contact_id = event->mtouch.contact_id; input_mt_slot(dev, event->mtouch.contact_id); @@ -327,10 +321,15 @@ static int xenkbd_probe(struct xenbus_device *dev, input_set_abs_params(mtouch, ABS_MT_PRESSURE, 0, 255, 0, 0); - input_mt_init_slots(mtouch, num_cont, 0); + ret = input_mt_init_slots(mtouch, num_cont, + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); + if (ret) { + input_free_device(mtouch); + xenbus_dev_fatal(info->xbdev, ret, + "input_mt_init_slots"); + goto error; + } - mtouch_size[KPARAM_MT_X] = width; - mtouch_size[KPARAM_MT_Y] = height; info->mtouch_cur_contact_id = -1; ret = input_register_device(mtouch); -- 2.7.4 --------------732AA74FE6E43547D6855880--