diff mbox

[v3] Fix modifier keys for Redragon Asura Keyboard

Message ID 20180321104331.22783-1-rombert@apache.org (mailing list archive)
State New, archived
Headers show

Commit Message

Robert Munteanu March 21, 2018, 10:43 a.m. UTC
The microdia family of keyboards uses a non-standard way of sending
modifier keys.

The down event always sets the first bit to 0x04 and the second keycode
to a custom value For instance, left shift sends the following bits

  04 02 00 00 00 00 00 00

while left control sends

  04 01 00 00 00 00 00 00

As a result all modifier keys are mapped to left shift and the keyboard is
non-functional in that respect. To solve the problem, we capture the
raw data in raw_event and manually generate the correct input events.

The keyboard functions mostly as expected now, with only a few minor
issues:

- two USB devices are detected instead of 1
- some key combinations are not triggered - e.g.
  left shift + left ctrl + p. However, the same combination is recognized
  with the right shift key.

Changelog:

- v2: modifier keys work, some combinations are still troublesome
- v3: style cleanup, rebase on top of 4.14
- v4: remove most debugging calls, make init info useful for user,
  rebased on top of 4.15

Signed-off-by: Robert Munteanu <rombert@apache.org>
---
 drivers/hid/Kconfig        |   9 +++
 drivers/hid/Makefile       |   2 +-
 drivers/hid/hid-core.c     |   3 +
 drivers/hid/hid-ids.h      |   3 +
 drivers/hid/hid-microdia.c | 148 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 164 insertions(+), 1 deletion(-)
 create mode 100644 drivers/hid/hid-microdia.c

Comments

Benjamin Tissoires March 21, 2018, 4:12 p.m. UTC | #1
Hi Robert,

First, apologies for not answering to the RFC. I missed it and it fell
down in my INBOX.

On Wed, Mar 21, 2018 at 11:43 AM, Robert Munteanu <rombert@apache.org> wrote:
> The microdia family of keyboards uses a non-standard way of sending
> modifier keys.
>
> The down event always sets the first bit to 0x04 and the second keycode

Pretty sure you are talking about bytes here, not bits.
And in the HID world, the first byte is usually a report ID.

> to a custom value For instance, left shift sends the following bits
>
>   04 02 00 00 00 00 00 00
>
> while left control sends
>
>   04 01 00 00 00 00 00 00

This sounds like bit(0) is mapped to LEFT_SHIFT and bit(1) mapped to
LEFT_CONTROL in the second byte.
Fortunately, LeftControl is designed in HID as 0xe0 in the keyboard
HID usage table, and LeftShift is 0xe1. So that would match the
behavior you are seeing.
If you have 04 04 00 00 00 00 00 00 when pressing LeftAlt, then
definitively you are just facing a bitmask, which is fairly common.

>
> As a result all modifier keys are mapped to left shift and the keyboard is
> non-functional in that respect. To solve the problem, we capture the
> raw data in raw_event and manually generate the correct input events.

I'd like to see the hid-recorder events from these keypresses. The
device might be buggy, but I have a gut feeling your solution is not
the simplest one.
Please grab hid-recorder from http://bentiss.github.io/hid-replay-docs/

>
> The keyboard functions mostly as expected now, with only a few minor
> issues:
>
> - two USB devices are detected instead of 1

Well, that should be easy enough to solve

> - some key combinations are not triggered - e.g.
>   left shift + left ctrl + p. However, the same combination is recognized
>   with the right shift key.

Could you add this combination in the hid-recorder output too?

more comments inlined:

>
> Changelog:
>
> - v2: modifier keys work, some combinations are still troublesome
> - v3: style cleanup, rebase on top of 4.14
> - v4: remove most debugging calls, make init info useful for user,
>   rebased on top of 4.15
>
> Signed-off-by: Robert Munteanu <rombert@apache.org>
> ---
>  drivers/hid/Kconfig        |   9 +++
>  drivers/hid/Makefile       |   2 +-
>  drivers/hid/hid-core.c     |   3 +
>  drivers/hid/hid-ids.h      |   3 +
>  drivers/hid/hid-microdia.c | 148 +++++++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 164 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/hid/hid-microdia.c
>
> diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> index 779c5ae47f36..c3350f2ec4ea 100644
> --- a/drivers/hid/Kconfig
> +++ b/drivers/hid/Kconfig
> @@ -548,6 +548,15 @@ config HID_MAYFLASH
>         Say Y here if you have HJZ Mayflash PS3 game controller adapters
>         and want to enable force feedback support.
>
> +config HID_MICRODIA
> +       tristate "Microdia based keyboards"
> +       depends on HID
> +       default !EXPERT
> +       ---help---
> +    Support for Microdia devices that are not compliant with the HID standard.
> +
> +    One known example if the Redragon Asura Keyboard.
> +
>  config HID_MICROSOFT
>         tristate "Microsoft non-fully HID-compliant devices"
>         depends on HID
> diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> index 235bd2a7b333..e66a305876c5 100644
> --- a/drivers/hid/Makefile
> +++ b/drivers/hid/Makefile
> @@ -62,6 +62,7 @@ obj-$(CONFIG_HID_LOGITECH_DJ) += hid-logitech-dj.o
>  obj-$(CONFIG_HID_LOGITECH_HIDPP)       += hid-logitech-hidpp.o
>  obj-$(CONFIG_HID_MAGICMOUSE)   += hid-magicmouse.o
>  obj-$(CONFIG_HID_MAYFLASH)     += hid-mf.o
> +obj-$(CONFIG_HID_MICRODIA)  += hid-microdia.o
>  obj-$(CONFIG_HID_MICROSOFT)    += hid-microsoft.o
>  obj-$(CONFIG_HID_MONTEREY)     += hid-monterey.o
>  obj-$(CONFIG_HID_MULTITOUCH)   += hid-multitouch.o
> @@ -121,4 +122,3 @@ obj-$(CONFIG_USB_KBD)               += usbhid/
>
>  obj-$(CONFIG_I2C_HID)          += i2c-hid/
>
> -obj-$(CONFIG_INTEL_ISH_HID)    += intel-ish-hid/
> diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> index 0c3f608131cf..b36c2df4b755 100644
> --- a/drivers/hid/hid-core.c
> +++ b/drivers/hid/hid-core.c
> @@ -2393,6 +2393,9 @@ static const struct hid_device_id hid_have_special_driver[] = {
>  #endif
>  #if IS_ENABLED(CONFIG_HID_ZYDACRON)
>         { HID_USB_DEVICE(USB_VENDOR_ID_ZYDACRON, USB_DEVICE_ID_ZYDACRON_REMOTE_CONTROL) },
> +#endif
> +#if IS_ENABLED(CONFIG_HID_MICRODIA)
> +       { HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,  USB_DEVICE_ID_REDRAGON_ASURA) },
>  #endif

You don't need this hunk anymore since v4.15 IIRC

>         { }
>  };
> diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
> index 5da3d6256d25..146869e55c5a 100644
> --- a/drivers/hid/hid-ids.h
> +++ b/drivers/hid/hid-ids.h
> @@ -1171,4 +1171,7 @@
>  #define USB_VENDOR_ID_UGTIZER                  0x2179
>  #define USB_DEVICE_ID_UGTIZER_TABLET_GP0610    0x0053
>
> +#define USB_VENDOR_ID_MICRODIA          0x0c45
> +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
> +
>  #endif
> diff --git a/drivers/hid/hid-microdia.c b/drivers/hid/hid-microdia.c
> new file mode 100644
> index 000000000000..f9d8de18a989
> --- /dev/null
> +++ b/drivers/hid/hid-microdia.c
> @@ -0,0 +1,148 @@

missing the SPDX identifier
(see Documentation/process/license-rules.rst)

> +/*
> + *  HID driver for Microdia-based keyboards
> + *
> + *  Copyright (c) 2017 Robert Munteanu
> + */
> +
> +/*
> + * 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.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/input.h>
> +#include <linux/hid.h>
> +#include <linux/module.h>
> +#include <linux/log2.h>
> +#include <linux/input-event-codes.h>
> +
> +#include "hid-ids.h"
> +
> +
> +// The microdia family of keyboards uses a non-standard way of sending
> +// modifier keys

Unless it has changed since last time I checked, we do not use C++ comments
(see Documentation/process/coding-style.rst)

> +//
> +// The down event always sets the first bit to 0x04 and the second keycode
> +// to a custom value. For instance, left shift sends the following bits
> +//
> +//   04 02 00 00 00 00 00 00
> +//
> +// while left control sends
> +//
> +//   04 01 00 00 00 00 00 00
> +//
> +// Unfortunately these are all mapped to left shift and the keyboard is
> +// non-functional in that respect. To solve the problem, we capture the
> +// raw data in raw_event and manually generate the correct input events
> +//
> +// TODO
> +//
> +// 1. Some modifiers keys still don't work, e.g. Ctrl-Shift-P
> +//    Interestingly enough, this happens when pressing the physical
> +//    left shift key, but now when pressing the physical right shift key.
> +//    hexdump does not show them either.
> +// 2. A second USB keyboard is registered, but it should be removed
> +// 3. Modifier keys sometimes get stuck, need to re-press to clear
> +
> +static int microdia_input_configured(struct hid_device *hdev,
> +       struct hid_input *hi)
> +{
> +
> +       hid_info(hdev, "Keyboard configured with limited support (modifier keys may get stuck, some modifiers combinations with left-shift not working) ");
> +
> +       hid_set_drvdata(hdev, hi);
> +
> +       return 0;
> +}
> +
> +static int microdia_input_mapping(struct hid_device *hdev, struct hid_input *hi,
> +               struct hid_field *field, struct hid_usage *usage,
> +               unsigned long **bit, int *max)
> +{
> +       // do not map left shift since we will manually generate input
> +       // events in microdia_raw_event
> +       if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD)
> +               if ((usage->hid & HID_USAGE) == 0xe1)
> +                       return -1;
> +
> +       return 0;
> +}
> +
> +// array index of a modifier matches the bit index in the data payload
> +// the modifier data is always stored in the second int
> +// e.g. for left alt the 1 bit is set - 04 04 ...
> +// TODO - second entry should be left shift, but that's not possible
> +// since we ignore it in the mapping
> +static int microdia_modifiers[7] = {
> +               KEY_LEFTCTRL,
> +               KEY_RIGHTSHIFT,
> +               KEY_LEFTALT,
> +               KEY_LEFTMETA,
> +               KEY_RIGHTCTRL,
> +               KEY_RIGHTSHIFT,
> +               KEY_RIGHTALT
> +};
> +
> +static int microdia_last_handled_modifier;
> +
> +static int microdia_raw_event(struct hid_device *hdev,
> +               struct hid_report *report, u8 *data, int size)
> +{
> +       int i, changed_key, new_value, mapped_key;
> +       struct hid_input *hi;
> +
> +       // 1. validate that we get 8 bits of the for 04 xx 00 00 00 00 00 00
> +       if (size != 8)
> +               return 0;
> +
> +       if (data[0] != 4)
> +               return 0;
> +
> +       // TODO - can I somehow use a bit mask? data & 0x00ffffff != 0
> +       for (i = 2; i < size; i++)
> +               if (data[i] != 0)
> +                       return 0;
> +
> +       // TODO - don't process the keyup event 04 00 00 00 00 00 00 00

That's a lot of TODO in such a simple driver :/

> +       // if we don't expect a modifier key 'up' event
> +
> +       // 2. detect based on previous data what key was pressed or depressed
> +       // a key was pressed or depressed if its bit has a different value
> +       // between this and the previous invocation. If the bit is set
> +       // it was pressed
> +
> +       changed_key = data[1] ^ microdia_last_handled_modifier;
> +       new_value = (data[1] & changed_key) != 0;
> +       // TODO - is ilog2 really needed?
> +       mapped_key = microdia_modifiers[ilog2(changed_key)];

What if you get 2 changed keys at a time?

Anyway, before giving you a ACK or NACK on the driver, the behavior
from the keyboard firmware looks sane and pretty common. So my guess
is that there is something wrong in the report descriptors, and I need
the hid-recorder output to have a better idea of what is wrong with
our current handling of this keyboard.

Cheers,
Benjamin

> +
> +       // 3. report the key event and track what was sent
> +       hi = hid_get_drvdata(hdev);
> +
> +       input_report_key(hi->input, mapped_key, new_value);
> +
> +       microdia_last_handled_modifier = data[1];
> +
> +       return 1;
> +}
> +
> +static const struct hid_device_id microdia_devices[] = {
> +       {HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA, USB_DEVICE_ID_REDRAGON_ASURA)},
> +       {}
> +};
> +
> +MODULE_DEVICE_TABLE(hid, microdia_devices);
> +
> +static struct hid_driver microdia_driver = {
> +       .name = "microdia",
> +       .input_mapping = microdia_input_mapping,
> +       .id_table = microdia_devices,
> +       .raw_event = microdia_raw_event,
> +       .input_configured = microdia_input_configured,
> +};
> +
> +module_hid_driver(microdia_driver);
> +
> +MODULE_LICENSE("GPL");
> --
> 2.16.2
>
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Robert Munteanu March 21, 2018, 4:33 p.m. UTC | #2
Hi Benjamin,

On Wed, 2018-03-21 at 17:12 +0100, Benjamin Tissoires wrote:
> Hi Robert,
> 
> First, apologies for not answering to the RFC. I missed it and it
> fell
> down in my INBOX.
> 
> On Wed, Mar 21, 2018 at 11:43 AM, Robert Munteanu <rombert@apache.org
> > wrote:
> > The microdia family of keyboards uses a non-standard way of sending
> > modifier keys.
> > 
> > The down event always sets the first bit to 0x04 and the second
> > keycode
> 
> Pretty sure you are talking about bytes here, not bits.
> And in the HID world, the first byte is usually a report ID.

Right, thanks for spotting that.

> 
> > to a custom value For instance, left shift sends the following bits
> > 
> >   04 02 00 00 00 00 00 00
> > 
> > while left control sends
> > 
> >   04 01 00 00 00 00 00 00
> 
> This sounds like bit(0) is mapped to LEFT_SHIFT and bit(1) mapped to
> LEFT_CONTROL in the second byte.
> Fortunately, LeftControl is designed in HID as 0xe0 in the keyboard
> HID usage table, and LeftShift is 0xe1. So that would match the
> behavior you are seeing.
> If you have 04 04 00 00 00 00 00 00 when pressing LeftAlt, then
> definitively you are just facing a bitmask, which is fairly common.
> 
> > 
> > As a result all modifier keys are mapped to left shift and the
> > keyboard is
> > non-functional in that respect. To solve the problem, we capture
> > the
> > raw data in raw_event and manually generate the correct input
> > events.
> 
> I'd like to see the hid-recorder events from these keypresses. The
> device might be buggy, but I have a gut feeling your solution is not
> the simplest one.
> Please grab hid-recorder from http://bentiss.github.io/hid-replay-
> docs/

See below, I recorded the output for pressing left ctrl, left alt, left
shift, right ctrl, right alt, right shift, meta.

D: 0
R: 169 05 0c 09 01 a1 01 85 01 19 00 2a 80 03 15 00 26 80 03 95 01 75
10 81 00 c0 05 01 09 80 a1 01 85 02 19 81 29 83 15 00 25 01 75 01 95 03
81 02 95 05 81 01 c0 06 00 ff 09 01 a1 01 85 03 1a f1 00 2a f8 00 15 00
25 01 75 01 95 08 81 02 c0 05 01 09 06 a1 01 85 04 05 07 19 e0 29 e7 15
00 25 01 75 01 95 08 81 00 95 30 75 01 15 00 25 01 05 07 19 00 29 2f 81
02 c0 05 01 09 06 a1 01 85 05 95 38 75 01 15 00 25 01 05 07 19 30 29 67
81 02 c0 05 01 09 06 a1 01 85 06 95 38 75 01 15 00 25 01 05 07 19 68 29
9f 81 02 c0
N: USB Keyboard
P: usb-0000:00:14.0-6/input1
I: 3 0c45 760b
D: 0
E: 0.000000 8 04 01 00 00 00 00 00 00
E: 0.039920 8 04 00 00 00 00 00 00 00
E: 0.751952 8 04 04 00 00 00 00 00 00
E: 0.823977 8 04 00 00 00 00 00 00 00
E: 2.639887 8 04 02 00 00 00 00 00 00
E: 2.711896 8 04 00 00 00 00 00 00 00
E: 3.583932 8 04 10 00 00 00 00 00 00
E: 3.663919 8 04 00 00 00 00 00 00 00
E: 4.871886 8 04 40 00 00 00 00 00 00
E: 4.935906 8 04 00 00 00 00 00 00 00
E: 6.503872 8 04 20 00 00 00 00 00 00
E: 6.575850 8 04 00 00 00 00 00 00 00
E: 7.383844 8 04 08 00 00 00 00 00 00
E: 7.455861 8 04 00 00 00 00 00 00 00

> 
> > 
> > The keyboard functions mostly as expected now, with only a few
> > minor
> > issues:
> > 
> > - two USB devices are detected instead of 1
> 
> Well, that should be easy enough to solve

I think so, but I could not find a way how to do that.

> 
> > - some key combinations are not triggered - e.g.
> >   left shift + left ctrl + p. However, the same combination is
> > recognized
> >   with the right shift key.
> 
> Could you add this combination in the hid-recorder output too?

This is what Left Ctrl + Shift + U produces:

E: 24.575686 8 04 01 00 00 00 00 00 00
E: 24.951689 8 04 03 00 00 00 00 00 00
E: 26.719615 8 04 01 00 00 00 00 00 00
E: 26.727611 8 04 00 00 00 00 00 00 00

On the other hand, Right Ctrl + Shift + U produces:

E: 55.911268 8 04 10 00 00 00 00 00 00
E: 56.119280 8 04 30 00 00 00 00 00 00
E: 56.599319 8 04 30 00 00 00 01 00 00
E: 56.703282 8 04 30 00 00 00 00 00 00
E: 56.815278 8 04 20 00 00 00 00 00 00
E: 56.823255 8 04 00 00 00 00 00 00 00

It looks suspicious that the keypress is not registered. Do I need to
boot a kernel without my patch applied?

> more comments inlined:
> 
> > 
> > Changelog:
> > 
> > - v2: modifier keys work, some combinations are still troublesome
> > - v3: style cleanup, rebase on top of 4.14
> > - v4: remove most debugging calls, make init info useful for user,
> >   rebased on top of 4.15
> > 
> > Signed-off-by: Robert Munteanu <rombert@apache.org>
> > ---
> >  drivers/hid/Kconfig        |   9 +++
> >  drivers/hid/Makefile       |   2 +-
> >  drivers/hid/hid-core.c     |   3 +
> >  drivers/hid/hid-ids.h      |   3 +
> >  drivers/hid/hid-microdia.c | 148
> > +++++++++++++++++++++++++++++++++++++++++++++
> >  5 files changed, 164 insertions(+), 1 deletion(-)
> >  create mode 100644 drivers/hid/hid-microdia.c
> > 
> > diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> > index 779c5ae47f36..c3350f2ec4ea 100644
> > --- a/drivers/hid/Kconfig
> > +++ b/drivers/hid/Kconfig
> > @@ -548,6 +548,15 @@ config HID_MAYFLASH
> >         Say Y here if you have HJZ Mayflash PS3 game controller
> > adapters
> >         and want to enable force feedback support.
> > 
> > +config HID_MICRODIA
> > +       tristate "Microdia based keyboards"
> > +       depends on HID
> > +       default !EXPERT
> > +       ---help---
> > +    Support for Microdia devices that are not compliant with the
> > HID standard.
> > +
> > +    One known example if the Redragon Asura Keyboard.
> > +
> >  config HID_MICROSOFT
> >         tristate "Microsoft non-fully HID-compliant devices"
> >         depends on HID
> > diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> > index 235bd2a7b333..e66a305876c5 100644
> > --- a/drivers/hid/Makefile
> > +++ b/drivers/hid/Makefile
> > @@ -62,6 +62,7 @@ obj-$(CONFIG_HID_LOGITECH_DJ) += hid-logitech-
> > dj.o
> >  obj-$(CONFIG_HID_LOGITECH_HIDPP)       += hid-logitech-hidpp.o
> >  obj-$(CONFIG_HID_MAGICMOUSE)   += hid-magicmouse.o
> >  obj-$(CONFIG_HID_MAYFLASH)     += hid-mf.o
> > +obj-$(CONFIG_HID_MICRODIA)  += hid-microdia.o
> >  obj-$(CONFIG_HID_MICROSOFT)    += hid-microsoft.o
> >  obj-$(CONFIG_HID_MONTEREY)     += hid-monterey.o
> >  obj-$(CONFIG_HID_MULTITOUCH)   += hid-multitouch.o
> > @@ -121,4 +122,3 @@ obj-$(CONFIG_USB_KBD)               += usbhid/
> > 
> >  obj-$(CONFIG_I2C_HID)          += i2c-hid/
> > 
> > -obj-$(CONFIG_INTEL_ISH_HID)    += intel-ish-hid/
> > diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> > index 0c3f608131cf..b36c2df4b755 100644
> > --- a/drivers/hid/hid-core.c
> > +++ b/drivers/hid/hid-core.c
> > @@ -2393,6 +2393,9 @@ static const struct hid_device_id
> > hid_have_special_driver[] = {
> >  #endif
> >  #if IS_ENABLED(CONFIG_HID_ZYDACRON)
> >         { HID_USB_DEVICE(USB_VENDOR_ID_ZYDACRON,
> > USB_DEVICE_ID_ZYDACRON_REMOTE_CONTROL) },
> > +#endif
> > +#if IS_ENABLED(CONFIG_HID_MICRODIA)
> > +       {
> > HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,  USB_DEVICE_ID_REDRAGON_ASUR
> > A) },
> >  #endif
> 
> You don't need this hunk anymore since v4.15 IIRC

Ack, will update and retest.

> 
> >         { }
> >  };
> > diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
> > index 5da3d6256d25..146869e55c5a 100644
> > --- a/drivers/hid/hid-ids.h
> > +++ b/drivers/hid/hid-ids.h
> > @@ -1171,4 +1171,7 @@
> >  #define USB_VENDOR_ID_UGTIZER                  0x2179
> >  #define USB_DEVICE_ID_UGTIZER_TABLET_GP0610    0x0053
> > 
> > +#define USB_VENDOR_ID_MICRODIA          0x0c45
> > +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
> > +
> >  #endif
> > diff --git a/drivers/hid/hid-microdia.c b/drivers/hid/hid-
> > microdia.c
> > new file mode 100644
> > index 000000000000..f9d8de18a989
> > --- /dev/null
> > +++ b/drivers/hid/hid-microdia.c
> > @@ -0,0 +1,148 @@
> 
> missing the SPDX identifier
> (see Documentation/process/license-rules.rst)

Ack, will update.

> 
> > +/*
> > + *  HID driver for Microdia-based keyboards
> > + *
> > + *  Copyright (c) 2017 Robert Munteanu
> > + */
> > +
> > +/*
> > + * 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.
> > + */
> > +
> > +#include <linux/device.h>
> > +#include <linux/input.h>
> > +#include <linux/hid.h>
> > +#include <linux/module.h>
> > +#include <linux/log2.h>
> > +#include <linux/input-event-codes.h>
> > +
> > +#include "hid-ids.h"
> > +
> > +
> > +// The microdia family of keyboards uses a non-standard way of
> > sending
> > +// modifier keys
> 
> Unless it has changed since last time I checked, we do not use C++
> comments
> (see Documentation/process/coding-style.rst)

Ack.

> 
> > +//
> > +// The down event always sets the first bit to 0x04 and the second
> > keycode
> > +// to a custom value. For instance, left shift sends the following
> > bits
> > +//
> > +//   04 02 00 00 00 00 00 00
> > +//
> > +// while left control sends
> > +//
> > +//   04 01 00 00 00 00 00 00
> > +//
> > +// Unfortunately these are all mapped to left shift and the
> > keyboard is
> > +// non-functional in that respect. To solve the problem, we
> > capture the
> > +// raw data in raw_event and manually generate the correct input
> > events
> > +//
> > +// TODO
> > +//
> > +// 1. Some modifiers keys still don't work, e.g. Ctrl-Shift-P
> > +//    Interestingly enough, this happens when pressing the
> > physical
> > +//    left shift key, but now when pressing the physical right
> > shift key.
> > +//    hexdump does not show them either.
> > +// 2. A second USB keyboard is registered, but it should be
> > removed
> > +// 3. Modifier keys sometimes get stuck, need to re-press to clear
> > +
> > +static int microdia_input_configured(struct hid_device *hdev,
> > +       struct hid_input *hi)
> > +{
> > +
> > +       hid_info(hdev, "Keyboard configured with limited support
> > (modifier keys may get stuck, some modifiers combinations with
> > left-shift not working) ");
> > +
> > +       hid_set_drvdata(hdev, hi);
> > +
> > +       return 0;
> > +}
> > +
> > +static int microdia_input_mapping(struct hid_device *hdev, struct
> > hid_input *hi,
> > +               struct hid_field *field, struct hid_usage *usage,
> > +               unsigned long **bit, int *max)
> > +{
> > +       // do not map left shift since we will manually generate
> > input
> > +       // events in microdia_raw_event
> > +       if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD)
> > +               if ((usage->hid & HID_USAGE) == 0xe1)
> > +                       return -1;
> > +
> > +       return 0;
> > +}
> > +
> > +// array index of a modifier matches the bit index in the data
> > payload
> > +// the modifier data is always stored in the second int
> > +// e.g. for left alt the 1 bit is set - 04 04 ...
> > +// TODO - second entry should be left shift, but that's not
> > possible
> > +// since we ignore it in the mapping
> > +static int microdia_modifiers[7] = {
> > +               KEY_LEFTCTRL,
> > +               KEY_RIGHTSHIFT,
> > +               KEY_LEFTALT,
> > +               KEY_LEFTMETA,
> > +               KEY_RIGHTCTRL,
> > +               KEY_RIGHTSHIFT,
> > +               KEY_RIGHTALT
> > +};
> > +
> > +static int microdia_last_handled_modifier;
> > +
> > +static int microdia_raw_event(struct hid_device *hdev,
> > +               struct hid_report *report, u8 *data, int size)
> > +{
> > +       int i, changed_key, new_value, mapped_key;
> > +       struct hid_input *hi;
> > +
> > +       // 1. validate that we get 8 bits of the for 04 xx 00 00 00
> > 00 00 00
> > +       if (size != 8)
> > +               return 0;
> > +
> > +       if (data[0] != 4)
> > +               return 0;
> > +
> > +       // TODO - can I somehow use a bit mask? data & 0x00ffffff
> > != 0
> > +       for (i = 2; i < size; i++)
> > +               if (data[i] != 0)
> > +                       return 0;
> > +
> > +       // TODO - don't process the keyup event 04 00 00 00 00 00
> > 00 00
> 
> That's a lot of TODO in such a simple driver :/

Yes, well that's what I get for learning to write hid drivers by
example ... and C isn't my primary programming language either.

> 
> > +       // if we don't expect a modifier key 'up' event
> > +
> > +       // 2. detect based on previous data what key was pressed or
> > depressed
> > +       // a key was pressed or depressed if its bit has a
> > different value
> > +       // between this and the previous invocation. If the bit is
> > set
> > +       // it was pressed
> > +
> > +       changed_key = data[1] ^ microdia_last_handled_modifier;
> > +       new_value = (data[1] & changed_key) != 0;
> > +       // TODO - is ilog2 really needed?
> > +       mapped_key = microdia_modifiers[ilog2(changed_key)];
> 
> What if you get 2 changed keys at a time?

This could explain the problems that I've been getting with modifier
keys being 'stuck'.

> 
> Anyway, before giving you a ACK or NACK on the driver, the behavior
> from the keyboard firmware looks sane and pretty common. So my guess
> is that there is something wrong in the report descriptors, and I
> need
> the hid-recorder output to have a better idea of what is wrong with
> our current handling of this keyboard.

The output is inline. That being said, I'm aware that re-firing the
keypress events myself does not belong in a HID driver, but I'm eager
to work on this being massaged into something proper for inclusion.

Thanks for taking the time to review.

Robert

> 
> Cheers,
> Benjamin
> 
> > +
> > +       // 3. report the key event and track what was sent
> > +       hi = hid_get_drvdata(hdev);
> > +
> > +       input_report_key(hi->input, mapped_key, new_value);
> > +
> > +       microdia_last_handled_modifier = data[1];
> > +
> > +       return 1;
> > +}
> > +
> > +static const struct hid_device_id microdia_devices[] = {
> > +       {HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,
> > USB_DEVICE_ID_REDRAGON_ASURA)},
> > +       {}
> > +};
> > +
> > +MODULE_DEVICE_TABLE(hid, microdia_devices);
> > +
> > +static struct hid_driver microdia_driver = {
> > +       .name = "microdia",
> > +       .input_mapping = microdia_input_mapping,
> > +       .id_table = microdia_devices,
> > +       .raw_event = microdia_raw_event,
> > +       .input_configured = microdia_input_configured,
> > +};
> > +
> > +module_hid_driver(microdia_driver);
> > +
> > +MODULE_LICENSE("GPL");
> > --
> > 2.16.2
> > 

--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Ondrej Zary March 21, 2018, 4:51 p.m. UTC | #3
On Wednesday 21 March 2018 11:43:31 Robert Munteanu wrote:
> +#define USB_VENDOR_ID_MICRODIA          0x0c45
> +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b

Microdia is most probably an incorrect name. The 0c45 id probably belongs 
to "Sonix Technology Co., Ltd."
Robert Munteanu March 22, 2018, 8:17 a.m. UTC | #4
On Wed, 2018-03-21 at 17:51 +0100, Ondrej Zary wrote:
> On Wednesday 21 March 2018 11:43:31 Robert Munteanu wrote:
> > +#define USB_VENDOR_ID_MICRODIA          0x0c45
> > +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
> 
> Microdia is most probably an incorrect name. The 0c45 id probably
> belongs 
> to "Sonix Technology Co., Ltd."

Right, I was unsure about that. I'll remove the microdia references and
use sonix.

Robert
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Benjamin Tissoires March 22, 2018, 8:33 a.m. UTC | #5
On Wed, Mar 21, 2018 at 5:33 PM, Robert Munteanu <rombert@apache.org> wrote:
> Hi Benjamin,
>
> On Wed, 2018-03-21 at 17:12 +0100, Benjamin Tissoires wrote:
>> Hi Robert,
>>
>> First, apologies for not answering to the RFC. I missed it and it
>> fell
>> down in my INBOX.
>>
>> On Wed, Mar 21, 2018 at 11:43 AM, Robert Munteanu <rombert@apache.org
>> > wrote:
>> > The microdia family of keyboards uses a non-standard way of sending
>> > modifier keys.
>> >
>> > The down event always sets the first bit to 0x04 and the second
>> > keycode
>>
>> Pretty sure you are talking about bytes here, not bits.
>> And in the HID world, the first byte is usually a report ID.
>
> Right, thanks for spotting that.
>
>>
>> > to a custom value For instance, left shift sends the following bits
>> >
>> >   04 02 00 00 00 00 00 00
>> >
>> > while left control sends
>> >
>> >   04 01 00 00 00 00 00 00
>>
>> This sounds like bit(0) is mapped to LEFT_SHIFT and bit(1) mapped to
>> LEFT_CONTROL in the second byte.
>> Fortunately, LeftControl is designed in HID as 0xe0 in the keyboard
>> HID usage table, and LeftShift is 0xe1. So that would match the
>> behavior you are seeing.
>> If you have 04 04 00 00 00 00 00 00 when pressing LeftAlt, then
>> definitively you are just facing a bitmask, which is fairly common.
>>
>> >
>> > As a result all modifier keys are mapped to left shift and the
>> > keyboard is
>> > non-functional in that respect. To solve the problem, we capture
>> > the
>> > raw data in raw_event and manually generate the correct input
>> > events.
>>
>> I'd like to see the hid-recorder events from these keypresses. The
>> device might be buggy, but I have a gut feeling your solution is not
>> the simplest one.
>> Please grab hid-recorder from http://bentiss.github.io/hid-replay-
>> docs/
>
> See below, I recorded the output for pressing left ctrl, left alt, left
> shift, right ctrl, right alt, right shift, meta.
>
> D: 0
> R: 169 05 0c 09 01 a1 01 85 01 19 00 2a 80 03 15 00 26 80 03 95 01 75
> 10 81 00 c0 05 01 09 80 a1 01 85 02 19 81 29 83 15 00 25 01 75 01 95 03
> 81 02 95 05 81 01 c0 06 00 ff 09 01 a1 01 85 03 1a f1 00 2a f8 00 15 00
> 25 01 75 01 95 08 81 02 c0 05 01 09 06 a1 01 85 04 05 07 19 e0 29 e7 15
> 00 25 01 75 01 95 08 81 00 95 30 75 01 15 00 25 01 05 07 19 00 29 2f 81
> 02 c0 05 01 09 06 a1 01 85 05 95 38 75 01 15 00 25 01 05 07 19 30 29 67
> 81 02 c0 05 01 09 06 a1 01 85 06 95 38 75 01 15 00 25 01 05 07 19 68 29
> 9f 81 02 c0
> N: USB Keyboard
> P: usb-0000:00:14.0-6/input1
> I: 3 0c45 760b
> D: 0
> E: 0.000000 8 04 01 00 00 00 00 00 00
> E: 0.039920 8 04 00 00 00 00 00 00 00
> E: 0.751952 8 04 04 00 00 00 00 00 00
> E: 0.823977 8 04 00 00 00 00 00 00 00
> E: 2.639887 8 04 02 00 00 00 00 00 00
> E: 2.711896 8 04 00 00 00 00 00 00 00
> E: 3.583932 8 04 10 00 00 00 00 00 00
> E: 3.663919 8 04 00 00 00 00 00 00 00
> E: 4.871886 8 04 40 00 00 00 00 00 00
> E: 4.935906 8 04 00 00 00 00 00 00 00
> E: 6.503872 8 04 20 00 00 00 00 00 00
> E: 6.575850 8 04 00 00 00 00 00 00 00
> E: 7.383844 8 04 08 00 00 00 00 00 00
> E: 7.455861 8 04 00 00 00 00 00 00 00

Thanks. So it's indeed an issue with the report descriptor. Not sure
how this can also work under Windows.
FYI, the Report ID 4 translates to:

0x05, 0x01,                    // Usage Page (Generic Desktop)        78
0x09, 0x06,                    // Usage (Keyboard)                    80
0xa1, 0x01,                    // Collection (Application)            82
0x85, 0x04,                    //  Report ID (4)                      84
0x05, 0x07,                    //  Usage Page (Keyboard)              86
0x19, 0xe0,                    //  Usage Minimum (224)                88
0x29, 0xe7,                    //  Usage Maximum (231)                90
0x15, 0x00,                    //  Logical Minimum (0)                92
0x25, 0x01,                    //  Logical Maximum (1)                94
0x75, 0x01,                    //  Report Size (1)                    96
0x95, 0x08,                    //  Report Count (8)                   98
0x81, 0x00,                    //  Input (Data,Arr,Abs)               100
0x95, 0x30,                    //  Report Count (48)                  102
0x75, 0x01,                    //  Report Size (1)                    104
0x15, 0x00,                    //  Logical Minimum (0)                106
0x25, 0x01,                    //  Logical Maximum (1)                108
0x05, 0x07,                    //  Usage Page (Keyboard)              110
0x19, 0x00,                    //  Usage Minimum (0)                  112
0x29, 0x2f,                    //  Usage Maximum (47)                 114
0x81, 0x02,                    //  Input (Data,Var,Abs)               116
0xc0,                          // End Collection                      118

the problem lies in the byte offset 100. If you use "Input
(Data,Arr,Abs)", the logical min/max should not be 0,1 but 0,8 and the
keyboard should translate the various values based on this offset.
Here, the keyboard is using a plain bitfield, and so it should be
using 'Input (Data,Var,Abs)', which translates to '0x81, 0x02'
(instead of '0x81, 0x00').

The best solution for you is to introduce a report descriptor fixup.
See hid-aureal.c in the kernel tree for an example of a simple report
descriptor fixup.

>
>>
>> >
>> > The keyboard functions mostly as expected now, with only a few
>> > minor
>> > issues:
>> >
>> > - two USB devices are detected instead of 1
>>
>> Well, that should be easy enough to solve
>
> I think so, but I could not find a way how to do that.
>
>>
>> > - some key combinations are not triggered - e.g.
>> >   left shift + left ctrl + p. However, the same combination is
>> > recognized
>> >   with the right shift key.
>>
>> Could you add this combination in the hid-recorder output too?
>
> This is what Left Ctrl + Shift + U produces:
>
> E: 24.575686 8 04 01 00 00 00 00 00 00
> E: 24.951689 8 04 03 00 00 00 00 00 00
> E: 26.719615 8 04 01 00 00 00 00 00 00
> E: 26.727611 8 04 00 00 00 00 00 00 00
>
> On the other hand, Right Ctrl + Shift + U produces:
>
> E: 55.911268 8 04 10 00 00 00 00 00 00
> E: 56.119280 8 04 30 00 00 00 00 00 00
> E: 56.599319 8 04 30 00 00 00 01 00 00
> E: 56.703282 8 04 30 00 00 00 00 00 00
> E: 56.815278 8 04 20 00 00 00 00 00 00
> E: 56.823255 8 04 00 00 00 00 00 00 00
>
> It looks suspicious that the keypress is not registered. Do I need to
> boot a kernel without my patch applied?

This seems like a firmware issue, and I doubt we will be able to fix
it. Does the keyboard under Windows behave sanely?

Cheers,
Benjamin

>
>> more comments inlined:
>>
>> >
>> > Changelog:
>> >
>> > - v2: modifier keys work, some combinations are still troublesome
>> > - v3: style cleanup, rebase on top of 4.14
>> > - v4: remove most debugging calls, make init info useful for user,
>> >   rebased on top of 4.15
>> >
>> > Signed-off-by: Robert Munteanu <rombert@apache.org>
>> > ---
>> >  drivers/hid/Kconfig        |   9 +++
>> >  drivers/hid/Makefile       |   2 +-
>> >  drivers/hid/hid-core.c     |   3 +
>> >  drivers/hid/hid-ids.h      |   3 +
>> >  drivers/hid/hid-microdia.c | 148
>> > +++++++++++++++++++++++++++++++++++++++++++++
>> >  5 files changed, 164 insertions(+), 1 deletion(-)
>> >  create mode 100644 drivers/hid/hid-microdia.c
>> >
>> > diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
>> > index 779c5ae47f36..c3350f2ec4ea 100644
>> > --- a/drivers/hid/Kconfig
>> > +++ b/drivers/hid/Kconfig
>> > @@ -548,6 +548,15 @@ config HID_MAYFLASH
>> >         Say Y here if you have HJZ Mayflash PS3 game controller
>> > adapters
>> >         and want to enable force feedback support.
>> >
>> > +config HID_MICRODIA
>> > +       tristate "Microdia based keyboards"
>> > +       depends on HID
>> > +       default !EXPERT
>> > +       ---help---
>> > +    Support for Microdia devices that are not compliant with the
>> > HID standard.
>> > +
>> > +    One known example if the Redragon Asura Keyboard.
>> > +
>> >  config HID_MICROSOFT
>> >         tristate "Microsoft non-fully HID-compliant devices"
>> >         depends on HID
>> > diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
>> > index 235bd2a7b333..e66a305876c5 100644
>> > --- a/drivers/hid/Makefile
>> > +++ b/drivers/hid/Makefile
>> > @@ -62,6 +62,7 @@ obj-$(CONFIG_HID_LOGITECH_DJ) += hid-logitech-
>> > dj.o
>> >  obj-$(CONFIG_HID_LOGITECH_HIDPP)       += hid-logitech-hidpp.o
>> >  obj-$(CONFIG_HID_MAGICMOUSE)   += hid-magicmouse.o
>> >  obj-$(CONFIG_HID_MAYFLASH)     += hid-mf.o
>> > +obj-$(CONFIG_HID_MICRODIA)  += hid-microdia.o
>> >  obj-$(CONFIG_HID_MICROSOFT)    += hid-microsoft.o
>> >  obj-$(CONFIG_HID_MONTEREY)     += hid-monterey.o
>> >  obj-$(CONFIG_HID_MULTITOUCH)   += hid-multitouch.o
>> > @@ -121,4 +122,3 @@ obj-$(CONFIG_USB_KBD)               += usbhid/
>> >
>> >  obj-$(CONFIG_I2C_HID)          += i2c-hid/
>> >
>> > -obj-$(CONFIG_INTEL_ISH_HID)    += intel-ish-hid/
>> > diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
>> > index 0c3f608131cf..b36c2df4b755 100644
>> > --- a/drivers/hid/hid-core.c
>> > +++ b/drivers/hid/hid-core.c
>> > @@ -2393,6 +2393,9 @@ static const struct hid_device_id
>> > hid_have_special_driver[] = {
>> >  #endif
>> >  #if IS_ENABLED(CONFIG_HID_ZYDACRON)
>> >         { HID_USB_DEVICE(USB_VENDOR_ID_ZYDACRON,
>> > USB_DEVICE_ID_ZYDACRON_REMOTE_CONTROL) },
>> > +#endif
>> > +#if IS_ENABLED(CONFIG_HID_MICRODIA)
>> > +       {
>> > HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,  USB_DEVICE_ID_REDRAGON_ASUR
>> > A) },
>> >  #endif
>>
>> You don't need this hunk anymore since v4.15 IIRC
>
> Ack, will update and retest.
>
>>
>> >         { }
>> >  };
>> > diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
>> > index 5da3d6256d25..146869e55c5a 100644
>> > --- a/drivers/hid/hid-ids.h
>> > +++ b/drivers/hid/hid-ids.h
>> > @@ -1171,4 +1171,7 @@
>> >  #define USB_VENDOR_ID_UGTIZER                  0x2179
>> >  #define USB_DEVICE_ID_UGTIZER_TABLET_GP0610    0x0053
>> >
>> > +#define USB_VENDOR_ID_MICRODIA          0x0c45
>> > +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
>> > +
>> >  #endif
>> > diff --git a/drivers/hid/hid-microdia.c b/drivers/hid/hid-
>> > microdia.c
>> > new file mode 100644
>> > index 000000000000..f9d8de18a989
>> > --- /dev/null
>> > +++ b/drivers/hid/hid-microdia.c
>> > @@ -0,0 +1,148 @@
>>
>> missing the SPDX identifier
>> (see Documentation/process/license-rules.rst)
>
> Ack, will update.
>
>>
>> > +/*
>> > + *  HID driver for Microdia-based keyboards
>> > + *
>> > + *  Copyright (c) 2017 Robert Munteanu
>> > + */
>> > +
>> > +/*
>> > + * 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.
>> > + */
>> > +
>> > +#include <linux/device.h>
>> > +#include <linux/input.h>
>> > +#include <linux/hid.h>
>> > +#include <linux/module.h>
>> > +#include <linux/log2.h>
>> > +#include <linux/input-event-codes.h>
>> > +
>> > +#include "hid-ids.h"
>> > +
>> > +
>> > +// The microdia family of keyboards uses a non-standard way of
>> > sending
>> > +// modifier keys
>>
>> Unless it has changed since last time I checked, we do not use C++
>> comments
>> (see Documentation/process/coding-style.rst)
>
> Ack.
>
>>
>> > +//
>> > +// The down event always sets the first bit to 0x04 and the second
>> > keycode
>> > +// to a custom value. For instance, left shift sends the following
>> > bits
>> > +//
>> > +//   04 02 00 00 00 00 00 00
>> > +//
>> > +// while left control sends
>> > +//
>> > +//   04 01 00 00 00 00 00 00
>> > +//
>> > +// Unfortunately these are all mapped to left shift and the
>> > keyboard is
>> > +// non-functional in that respect. To solve the problem, we
>> > capture the
>> > +// raw data in raw_event and manually generate the correct input
>> > events
>> > +//
>> > +// TODO
>> > +//
>> > +// 1. Some modifiers keys still don't work, e.g. Ctrl-Shift-P
>> > +//    Interestingly enough, this happens when pressing the
>> > physical
>> > +//    left shift key, but now when pressing the physical right
>> > shift key.
>> > +//    hexdump does not show them either.
>> > +// 2. A second USB keyboard is registered, but it should be
>> > removed
>> > +// 3. Modifier keys sometimes get stuck, need to re-press to clear
>> > +
>> > +static int microdia_input_configured(struct hid_device *hdev,
>> > +       struct hid_input *hi)
>> > +{
>> > +
>> > +       hid_info(hdev, "Keyboard configured with limited support
>> > (modifier keys may get stuck, some modifiers combinations with
>> > left-shift not working) ");
>> > +
>> > +       hid_set_drvdata(hdev, hi);
>> > +
>> > +       return 0;
>> > +}
>> > +
>> > +static int microdia_input_mapping(struct hid_device *hdev, struct
>> > hid_input *hi,
>> > +               struct hid_field *field, struct hid_usage *usage,
>> > +               unsigned long **bit, int *max)
>> > +{
>> > +       // do not map left shift since we will manually generate
>> > input
>> > +       // events in microdia_raw_event
>> > +       if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD)
>> > +               if ((usage->hid & HID_USAGE) == 0xe1)
>> > +                       return -1;
>> > +
>> > +       return 0;
>> > +}
>> > +
>> > +// array index of a modifier matches the bit index in the data
>> > payload
>> > +// the modifier data is always stored in the second int
>> > +// e.g. for left alt the 1 bit is set - 04 04 ...
>> > +// TODO - second entry should be left shift, but that's not
>> > possible
>> > +// since we ignore it in the mapping
>> > +static int microdia_modifiers[7] = {
>> > +               KEY_LEFTCTRL,
>> > +               KEY_RIGHTSHIFT,
>> > +               KEY_LEFTALT,
>> > +               KEY_LEFTMETA,
>> > +               KEY_RIGHTCTRL,
>> > +               KEY_RIGHTSHIFT,
>> > +               KEY_RIGHTALT
>> > +};
>> > +
>> > +static int microdia_last_handled_modifier;
>> > +
>> > +static int microdia_raw_event(struct hid_device *hdev,
>> > +               struct hid_report *report, u8 *data, int size)
>> > +{
>> > +       int i, changed_key, new_value, mapped_key;
>> > +       struct hid_input *hi;
>> > +
>> > +       // 1. validate that we get 8 bits of the for 04 xx 00 00 00
>> > 00 00 00
>> > +       if (size != 8)
>> > +               return 0;
>> > +
>> > +       if (data[0] != 4)
>> > +               return 0;
>> > +
>> > +       // TODO - can I somehow use a bit mask? data & 0x00ffffff
>> > != 0
>> > +       for (i = 2; i < size; i++)
>> > +               if (data[i] != 0)
>> > +                       return 0;
>> > +
>> > +       // TODO - don't process the keyup event 04 00 00 00 00 00
>> > 00 00
>>
>> That's a lot of TODO in such a simple driver :/
>
> Yes, well that's what I get for learning to write hid drivers by
> example ... and C isn't my primary programming language either.
>
>>
>> > +       // if we don't expect a modifier key 'up' event
>> > +
>> > +       // 2. detect based on previous data what key was pressed or
>> > depressed
>> > +       // a key was pressed or depressed if its bit has a
>> > different value
>> > +       // between this and the previous invocation. If the bit is
>> > set
>> > +       // it was pressed
>> > +
>> > +       changed_key = data[1] ^ microdia_last_handled_modifier;
>> > +       new_value = (data[1] & changed_key) != 0;
>> > +       // TODO - is ilog2 really needed?
>> > +       mapped_key = microdia_modifiers[ilog2(changed_key)];
>>
>> What if you get 2 changed keys at a time?
>
> This could explain the problems that I've been getting with modifier
> keys being 'stuck'.
>
>>
>> Anyway, before giving you a ACK or NACK on the driver, the behavior
>> from the keyboard firmware looks sane and pretty common. So my guess
>> is that there is something wrong in the report descriptors, and I
>> need
>> the hid-recorder output to have a better idea of what is wrong with
>> our current handling of this keyboard.
>
> The output is inline. That being said, I'm aware that re-firing the
> keypress events myself does not belong in a HID driver, but I'm eager
> to work on this being massaged into something proper for inclusion.
>
> Thanks for taking the time to review.
>
> Robert
>
>>
>> Cheers,
>> Benjamin
>>
>> > +
>> > +       // 3. report the key event and track what was sent
>> > +       hi = hid_get_drvdata(hdev);
>> > +
>> > +       input_report_key(hi->input, mapped_key, new_value);
>> > +
>> > +       microdia_last_handled_modifier = data[1];
>> > +
>> > +       return 1;
>> > +}
>> > +
>> > +static const struct hid_device_id microdia_devices[] = {
>> > +       {HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,
>> > USB_DEVICE_ID_REDRAGON_ASURA)},
>> > +       {}
>> > +};
>> > +
>> > +MODULE_DEVICE_TABLE(hid, microdia_devices);
>> > +
>> > +static struct hid_driver microdia_driver = {
>> > +       .name = "microdia",
>> > +       .input_mapping = microdia_input_mapping,
>> > +       .id_table = microdia_devices,
>> > +       .raw_event = microdia_raw_event,
>> > +       .input_configured = microdia_input_configured,
>> > +};
>> > +
>> > +module_hid_driver(microdia_driver);
>> > +
>> > +MODULE_LICENSE("GPL");
>> > --
>> > 2.16.2
>> >
>
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Robert Munteanu March 22, 2018, 1:39 p.m. UTC | #6
On Thu, 2018-03-22 at 09:33 +0100, Benjamin Tissoires wrote:
> On Wed, Mar 21, 2018 at 5:33 PM, Robert Munteanu <rombert@apache.org>
> wrote:
> > Hi Benjamin,
> > 
> > On Wed, 2018-03-21 at 17:12 +0100, Benjamin Tissoires wrote:
> > > Hi Robert,
> > > 
> > > First, apologies for not answering to the RFC. I missed it and it
> > > fell
> > > down in my INBOX.
> > > 
> > > On Wed, Mar 21, 2018 at 11:43 AM, Robert Munteanu <rombert@apache
> > > .org
> > > > wrote:
> > > > The microdia family of keyboards uses a non-standard way of
> > > > sending
> > > > modifier keys.
> > > > 
> > > > The down event always sets the first bit to 0x04 and the second
> > > > keycode
> > > 
> > > Pretty sure you are talking about bytes here, not bits.
> > > And in the HID world, the first byte is usually a report ID.
> > 
> > Right, thanks for spotting that.
> > 
> > > 
> > > > to a custom value For instance, left shift sends the following
> > > > bits
> > > > 
> > > >   04 02 00 00 00 00 00 00
> > > > 
> > > > while left control sends
> > > > 
> > > >   04 01 00 00 00 00 00 00
> > > 
> > > This sounds like bit(0) is mapped to LEFT_SHIFT and bit(1) mapped
> > > to
> > > LEFT_CONTROL in the second byte.
> > > Fortunately, LeftControl is designed in HID as 0xe0 in the
> > > keyboard
> > > HID usage table, and LeftShift is 0xe1. So that would match the
> > > behavior you are seeing.
> > > If you have 04 04 00 00 00 00 00 00 when pressing LeftAlt, then
> > > definitively you are just facing a bitmask, which is fairly
> > > common.
> > > 
> > > > 
> > > > As a result all modifier keys are mapped to left shift and the
> > > > keyboard is
> > > > non-functional in that respect. To solve the problem, we
> > > > capture
> > > > the
> > > > raw data in raw_event and manually generate the correct input
> > > > events.
> > > 
> > > I'd like to see the hid-recorder events from these keypresses.
> > > The
> > > device might be buggy, but I have a gut feeling your solution is
> > > not
> > > the simplest one.
> > > Please grab hid-recorder from http://bentiss.github.io/hid-replay
> > > -
> > > docs/
> > 
> > See below, I recorded the output for pressing left ctrl, left alt,
> > left
> > shift, right ctrl, right alt, right shift, meta.
> > 
> > D: 0
> > R: 169 05 0c 09 01 a1 01 85 01 19 00 2a 80 03 15 00 26 80 03 95 01
> > 75
> > 10 81 00 c0 05 01 09 80 a1 01 85 02 19 81 29 83 15 00 25 01 75 01
> > 95 03
> > 81 02 95 05 81 01 c0 06 00 ff 09 01 a1 01 85 03 1a f1 00 2a f8 00
> > 15 00
> > 25 01 75 01 95 08 81 02 c0 05 01 09 06 a1 01 85 04 05 07 19 e0 29
> > e7 15
> > 00 25 01 75 01 95 08 81 00 95 30 75 01 15 00 25 01 05 07 19 00 29
> > 2f 81
> > 02 c0 05 01 09 06 a1 01 85 05 95 38 75 01 15 00 25 01 05 07 19 30
> > 29 67
> > 81 02 c0 05 01 09 06 a1 01 85 06 95 38 75 01 15 00 25 01 05 07 19
> > 68 29
> > 9f 81 02 c0
> > N: USB Keyboard
> > P: usb-0000:00:14.0-6/input1
> > I: 3 0c45 760b
> > D: 0
> > E: 0.000000 8 04 01 00 00 00 00 00 00
> > E: 0.039920 8 04 00 00 00 00 00 00 00
> > E: 0.751952 8 04 04 00 00 00 00 00 00
> > E: 0.823977 8 04 00 00 00 00 00 00 00
> > E: 2.639887 8 04 02 00 00 00 00 00 00
> > E: 2.711896 8 04 00 00 00 00 00 00 00
> > E: 3.583932 8 04 10 00 00 00 00 00 00
> > E: 3.663919 8 04 00 00 00 00 00 00 00
> > E: 4.871886 8 04 40 00 00 00 00 00 00
> > E: 4.935906 8 04 00 00 00 00 00 00 00
> > E: 6.503872 8 04 20 00 00 00 00 00 00
> > E: 6.575850 8 04 00 00 00 00 00 00 00
> > E: 7.383844 8 04 08 00 00 00 00 00 00
> > E: 7.455861 8 04 00 00 00 00 00 00 00
> 
> Thanks. So it's indeed an issue with the report descriptor. Not sure
> how this can also work under Windows.
> FYI, the Report ID 4 translates to:
> 
> 0x05, 0x01,                    // Usage Page (Generic
> Desktop)        78
> 0x09, 0x06,                    // Usage
> (Keyboard)                    80
> 0xa1, 0x01,                    // Collection
> (Application)            82
> 0x85, 0x04,                    //  Report ID
> (4)                      84
> 0x05, 0x07,                    //  Usage Page
> (Keyboard)              86
> 0x19, 0xe0,                    //  Usage Minimum
> (224)                88
> 0x29, 0xe7,                    //  Usage Maximum
> (231)                90
> 0x15, 0x00,                    //  Logical Minimum
> (0)                92
> 0x25, 0x01,                    //  Logical Maximum
> (1)                94
> 0x75, 0x01,                    //  Report Size
> (1)                    96
> 0x95, 0x08,                    //  Report Count
> (8)                   98
> 0x81, 0x00,                    //  Input
> (Data,Arr,Abs)               100
> 0x95, 0x30,                    //  Report Count
> (48)                  102
> 0x75, 0x01,                    //  Report Size
> (1)                    104
> 0x15, 0x00,                    //  Logical Minimum
> (0)                106
> 0x25, 0x01,                    //  Logical Maximum
> (1)                108
> 0x05, 0x07,                    //  Usage Page
> (Keyboard)              110
> 0x19, 0x00,                    //  Usage Minimum
> (0)                  112
> 0x29, 0x2f,                    //  Usage Maximum
> (47)                 114
> 0x81, 0x02,                    //  Input
> (Data,Var,Abs)               116
> 0xc0,                          // End
> Collection                      118
> 
> the problem lies in the byte offset 100. If you use "Input
> (Data,Arr,Abs)", the logical min/max should not be 0,1 but 0,8 and
> the
> keyboard should translate the various values based on this offset.
> Here, the keyboard is using a plain bitfield, and so it should be
> using 'Input (Data,Var,Abs)', which translates to '0x81, 0x02'
> (instead of '0x81, 0x00').
> 
> The best solution for you is to introduce a report descriptor fixup.
> See hid-aureal.c in the kernel tree for an example of a simple report
> descriptor fixup.

Yes, that works! I applied a descriptor fixup and that is the only
change actually neded - I dropped all my other code.

I had a sense that the code was not the right approach and that the
problem was likely in the HID descriptor or HID parsing, but I was
unable to advance. Thanks for the extensive description.

> 
> > 
> > > 
> > > > 
> > > > The keyboard functions mostly as expected now, with only a few
> > > > minor
> > > > issues:
> > > > 
> > > > - two USB devices are detected instead of 1
> > > 
> > > Well, that should be easy enough to solve
> > 
> > I think so, but I could not find a way how to do that.
> > 
> > > 
> > > > - some key combinations are not triggered - e.g.
> > > >   left shift + left ctrl + p. However, the same combination is
> > > > recognized
> > > >   with the right shift key.
> > > 
> > > Could you add this combination in the hid-recorder output too?
> > 
> > This is what Left Ctrl + Shift + U produces:
> > 
> > E: 24.575686 8 04 01 00 00 00 00 00 00
> > E: 24.951689 8 04 03 00 00 00 00 00 00
> > E: 26.719615 8 04 01 00 00 00 00 00 00
> > E: 26.727611 8 04 00 00 00 00 00 00 00
> > 
> > On the other hand, Right Ctrl + Shift + U produces:
> > 
> > E: 55.911268 8 04 10 00 00 00 00 00 00
> > E: 56.119280 8 04 30 00 00 00 00 00 00
> > E: 56.599319 8 04 30 00 00 00 01 00 00
> > E: 56.703282 8 04 30 00 00 00 00 00 00
> > E: 56.815278 8 04 20 00 00 00 00 00 00
> > E: 56.823255 8 04 00 00 00 00 00 00 00
> > 
> > It looks suspicious that the keypress is not registered. Do I need
> > to
> > boot a kernel without my patch applied?
> 
> This seems like a firmware issue, and I doubt we will be able to fix
> it. Does the keyboard under Windows behave sanely?

I will need to double-check next week, I don't have a Windows machine
at hand right now.

Thanks,

Robert

> 
> Cheers,
> Benjamin
> 
> > 
> > > more comments inlined:
> > > 
> > > > 
> > > > Changelog:
> > > > 
> > > > - v2: modifier keys work, some combinations are still
> > > > troublesome
> > > > - v3: style cleanup, rebase on top of 4.14
> > > > - v4: remove most debugging calls, make init info useful for
> > > > user,
> > > >   rebased on top of 4.15
> > > > 
> > > > Signed-off-by: Robert Munteanu <rombert@apache.org>
> > > > ---
> > > >  drivers/hid/Kconfig        |   9 +++
> > > >  drivers/hid/Makefile       |   2 +-
> > > >  drivers/hid/hid-core.c     |   3 +
> > > >  drivers/hid/hid-ids.h      |   3 +
> > > >  drivers/hid/hid-microdia.c | 148
> > > > +++++++++++++++++++++++++++++++++++++++++++++
> > > >  5 files changed, 164 insertions(+), 1 deletion(-)
> > > >  create mode 100644 drivers/hid/hid-microdia.c
> > > > 
> > > > diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> > > > index 779c5ae47f36..c3350f2ec4ea 100644
> > > > --- a/drivers/hid/Kconfig
> > > > +++ b/drivers/hid/Kconfig
> > > > @@ -548,6 +548,15 @@ config HID_MAYFLASH
> > > >         Say Y here if you have HJZ Mayflash PS3 game controller
> > > > adapters
> > > >         and want to enable force feedback support.
> > > > 
> > > > +config HID_MICRODIA
> > > > +       tristate "Microdia based keyboards"
> > > > +       depends on HID
> > > > +       default !EXPERT
> > > > +       ---help---
> > > > +    Support for Microdia devices that are not compliant with
> > > > the
> > > > HID standard.
> > > > +
> > > > +    One known example if the Redragon Asura Keyboard.
> > > > +
> > > >  config HID_MICROSOFT
> > > >         tristate "Microsoft non-fully HID-compliant devices"
> > > >         depends on HID
> > > > diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> > > > index 235bd2a7b333..e66a305876c5 100644
> > > > --- a/drivers/hid/Makefile
> > > > +++ b/drivers/hid/Makefile
> > > > @@ -62,6 +62,7 @@ obj-$(CONFIG_HID_LOGITECH_DJ) += hid-
> > > > logitech-
> > > > dj.o
> > > >  obj-$(CONFIG_HID_LOGITECH_HIDPP)       += hid-logitech-hidpp.o
> > > >  obj-$(CONFIG_HID_MAGICMOUSE)   += hid-magicmouse.o
> > > >  obj-$(CONFIG_HID_MAYFLASH)     += hid-mf.o
> > > > +obj-$(CONFIG_HID_MICRODIA)  += hid-microdia.o
> > > >  obj-$(CONFIG_HID_MICROSOFT)    += hid-microsoft.o
> > > >  obj-$(CONFIG_HID_MONTEREY)     += hid-monterey.o
> > > >  obj-$(CONFIG_HID_MULTITOUCH)   += hid-multitouch.o
> > > > @@ -121,4 +122,3 @@ obj-$(CONFIG_USB_KBD)               +=
> > > > usbhid/
> > > > 
> > > >  obj-$(CONFIG_I2C_HID)          += i2c-hid/
> > > > 
> > > > -obj-$(CONFIG_INTEL_ISH_HID)    += intel-ish-hid/
> > > > diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> > > > index 0c3f608131cf..b36c2df4b755 100644
> > > > --- a/drivers/hid/hid-core.c
> > > > +++ b/drivers/hid/hid-core.c
> > > > @@ -2393,6 +2393,9 @@ static const struct hid_device_id
> > > > hid_have_special_driver[] = {
> > > >  #endif
> > > >  #if IS_ENABLED(CONFIG_HID_ZYDACRON)
> > > >         { HID_USB_DEVICE(USB_VENDOR_ID_ZYDACRON,
> > > > USB_DEVICE_ID_ZYDACRON_REMOTE_CONTROL) },
> > > > +#endif
> > > > +#if IS_ENABLED(CONFIG_HID_MICRODIA)
> > > > +       {
> > > > HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,  USB_DEVICE_ID_REDRAGON_
> > > > ASUR
> > > > A) },
> > > >  #endif
> > > 
> > > You don't need this hunk anymore since v4.15 IIRC
> > 
> > Ack, will update and retest.
> > 
> > > 
> > > >         { }
> > > >  };
> > > > diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
> > > > index 5da3d6256d25..146869e55c5a 100644
> > > > --- a/drivers/hid/hid-ids.h
> > > > +++ b/drivers/hid/hid-ids.h
> > > > @@ -1171,4 +1171,7 @@
> > > >  #define USB_VENDOR_ID_UGTIZER                  0x2179
> > > >  #define USB_DEVICE_ID_UGTIZER_TABLET_GP0610    0x0053
> > > > 
> > > > +#define USB_VENDOR_ID_MICRODIA          0x0c45
> > > > +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
> > > > +
> > > >  #endif
> > > > diff --git a/drivers/hid/hid-microdia.c b/drivers/hid/hid-
> > > > microdia.c
> > > > new file mode 100644
> > > > index 000000000000..f9d8de18a989
> > > > --- /dev/null
> > > > +++ b/drivers/hid/hid-microdia.c
> > > > @@ -0,0 +1,148 @@
> > > 
> > > missing the SPDX identifier
> > > (see Documentation/process/license-rules.rst)
> > 
> > Ack, will update.
> > 
> > > 
> > > > +/*
> > > > + *  HID driver for Microdia-based keyboards
> > > > + *
> > > > + *  Copyright (c) 2017 Robert Munteanu
> > > > + */
> > > > +
> > > > +/*
> > > > + * 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.
> > > > + */
> > > > +
> > > > +#include <linux/device.h>
> > > > +#include <linux/input.h>
> > > > +#include <linux/hid.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/log2.h>
> > > > +#include <linux/input-event-codes.h>
> > > > +
> > > > +#include "hid-ids.h"
> > > > +
> > > > +
> > > > +// The microdia family of keyboards uses a non-standard way of
> > > > sending
> > > > +// modifier keys
> > > 
> > > Unless it has changed since last time I checked, we do not use
> > > C++
> > > comments
> > > (see Documentation/process/coding-style.rst)
> > 
> > Ack.
> > 
> > > 
> > > > +//
> > > > +// The down event always sets the first bit to 0x04 and the
> > > > second
> > > > keycode
> > > > +// to a custom value. For instance, left shift sends the
> > > > following
> > > > bits
> > > > +//
> > > > +//   04 02 00 00 00 00 00 00
> > > > +//
> > > > +// while left control sends
> > > > +//
> > > > +//   04 01 00 00 00 00 00 00
> > > > +//
> > > > +// Unfortunately these are all mapped to left shift and the
> > > > keyboard is
> > > > +// non-functional in that respect. To solve the problem, we
> > > > capture the
> > > > +// raw data in raw_event and manually generate the correct
> > > > input
> > > > events
> > > > +//
> > > > +// TODO
> > > > +//
> > > > +// 1. Some modifiers keys still don't work, e.g. Ctrl-Shift-P
> > > > +//    Interestingly enough, this happens when pressing the
> > > > physical
> > > > +//    left shift key, but now when pressing the physical right
> > > > shift key.
> > > > +//    hexdump does not show them either.
> > > > +// 2. A second USB keyboard is registered, but it should be
> > > > removed
> > > > +// 3. Modifier keys sometimes get stuck, need to re-press to
> > > > clear
> > > > +
> > > > +static int microdia_input_configured(struct hid_device *hdev,
> > > > +       struct hid_input *hi)
> > > > +{
> > > > +
> > > > +       hid_info(hdev, "Keyboard configured with limited
> > > > support
> > > > (modifier keys may get stuck, some modifiers combinations with
> > > > left-shift not working) ");
> > > > +
> > > > +       hid_set_drvdata(hdev, hi);
> > > > +
> > > > +       return 0;
> > > > +}
> > > > +
> > > > +static int microdia_input_mapping(struct hid_device *hdev,
> > > > struct
> > > > hid_input *hi,
> > > > +               struct hid_field *field, struct hid_usage
> > > > *usage,
> > > > +               unsigned long **bit, int *max)
> > > > +{
> > > > +       // do not map left shift since we will manually
> > > > generate
> > > > input
> > > > +       // events in microdia_raw_event
> > > > +       if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD)
> > > > +               if ((usage->hid & HID_USAGE) == 0xe1)
> > > > +                       return -1;
> > > > +
> > > > +       return 0;
> > > > +}
> > > > +
> > > > +// array index of a modifier matches the bit index in the data
> > > > payload
> > > > +// the modifier data is always stored in the second int
> > > > +// e.g. for left alt the 1 bit is set - 04 04 ...
> > > > +// TODO - second entry should be left shift, but that's not
> > > > possible
> > > > +// since we ignore it in the mapping
> > > > +static int microdia_modifiers[7] = {
> > > > +               KEY_LEFTCTRL,
> > > > +               KEY_RIGHTSHIFT,
> > > > +               KEY_LEFTALT,
> > > > +               KEY_LEFTMETA,
> > > > +               KEY_RIGHTCTRL,
> > > > +               KEY_RIGHTSHIFT,
> > > > +               KEY_RIGHTALT
> > > > +};
> > > > +
> > > > +static int microdia_last_handled_modifier;
> > > > +
> > > > +static int microdia_raw_event(struct hid_device *hdev,
> > > > +               struct hid_report *report, u8 *data, int size)
> > > > +{
> > > > +       int i, changed_key, new_value, mapped_key;
> > > > +       struct hid_input *hi;
> > > > +
> > > > +       // 1. validate that we get 8 bits of the for 04 xx 00
> > > > 00 00
> > > > 00 00 00
> > > > +       if (size != 8)
> > > > +               return 0;
> > > > +
> > > > +       if (data[0] != 4)
> > > > +               return 0;
> > > > +
> > > > +       // TODO - can I somehow use a bit mask? data &
> > > > 0x00ffffff
> > > > != 0
> > > > +       for (i = 2; i < size; i++)
> > > > +               if (data[i] != 0)
> > > > +                       return 0;
> > > > +
> > > > +       // TODO - don't process the keyup event 04 00 00 00 00
> > > > 00
> > > > 00 00
> > > 
> > > That's a lot of TODO in such a simple driver :/
> > 
> > Yes, well that's what I get for learning to write hid drivers by
> > example ... and C isn't my primary programming language either.
> > 
> > > 
> > > > +       // if we don't expect a modifier key 'up' event
> > > > +
> > > > +       // 2. detect based on previous data what key was
> > > > pressed or
> > > > depressed
> > > > +       // a key was pressed or depressed if its bit has a
> > > > different value
> > > > +       // between this and the previous invocation. If the bit
> > > > is
> > > > set
> > > > +       // it was pressed
> > > > +
> > > > +       changed_key = data[1] ^ microdia_last_handled_modifier;
> > > > +       new_value = (data[1] & changed_key) != 0;
> > > > +       // TODO - is ilog2 really needed?
> > > > +       mapped_key = microdia_modifiers[ilog2(changed_key)];
> > > 
> > > What if you get 2 changed keys at a time?
> > 
> > This could explain the problems that I've been getting with
> > modifier
> > keys being 'stuck'.
> > 
> > > 
> > > Anyway, before giving you a ACK or NACK on the driver, the
> > > behavior
> > > from the keyboard firmware looks sane and pretty common. So my
> > > guess
> > > is that there is something wrong in the report descriptors, and I
> > > need
> > > the hid-recorder output to have a better idea of what is wrong
> > > with
> > > our current handling of this keyboard.
> > 
> > The output is inline. That being said, I'm aware that re-firing the
> > keypress events myself does not belong in a HID driver, but I'm
> > eager
> > to work on this being massaged into something proper for inclusion.
> > 
> > Thanks for taking the time to review.
> > 
> > Robert
> > 
> > > 
> > > Cheers,
> > > Benjamin
> > > 
> > > > +
> > > > +       // 3. report the key event and track what was sent
> > > > +       hi = hid_get_drvdata(hdev);
> > > > +
> > > > +       input_report_key(hi->input, mapped_key, new_value);
> > > > +
> > > > +       microdia_last_handled_modifier = data[1];
> > > > +
> > > > +       return 1;
> > > > +}
> > > > +
> > > > +static const struct hid_device_id microdia_devices[] = {
> > > > +       {HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,
> > > > USB_DEVICE_ID_REDRAGON_ASURA)},
> > > > +       {}
> > > > +};
> > > > +
> > > > +MODULE_DEVICE_TABLE(hid, microdia_devices);
> > > > +
> > > > +static struct hid_driver microdia_driver = {
> > > > +       .name = "microdia",
> > > > +       .input_mapping = microdia_input_mapping,
> > > > +       .id_table = microdia_devices,
> > > > +       .raw_event = microdia_raw_event,
> > > > +       .input_configured = microdia_input_configured,
> > > > +};
> > > > +
> > > > +module_hid_driver(microdia_driver);
> > > > +
> > > > +MODULE_LICENSE("GPL");
> > > > --
> > > > 2.16.2
> > > > 

--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Robert Munteanu March 22, 2018, 1:40 p.m. UTC | #7
On Thu, 2018-03-22 at 09:17 +0100, Robert Munteanu wrote:
> On Wed, 2018-03-21 at 17:51 +0100, Ondrej Zary wrote:
> > On Wednesday 21 March 2018 11:43:31 Robert Munteanu wrote:
> > > +#define USB_VENDOR_ID_MICRODIA          0x0c45
> > > +#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
> > 
> > Microdia is most probably an incorrect name. The 0c45 id probably
> > belongs 
> > to "Sonix Technology Co., Ltd."
> 
> Right, I was unsure about that. I'll remove the microdia references
> and
> use sonix.

I see the following in hid-ids.h

  define USB_VENDOR_ID_JESS            0x0c45

which I guess I should use since it's already defined in there.

Robert
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 779c5ae47f36..c3350f2ec4ea 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -548,6 +548,15 @@  config HID_MAYFLASH
 	Say Y here if you have HJZ Mayflash PS3 game controller adapters
 	and want to enable force feedback support.
 
+config HID_MICRODIA
+	tristate "Microdia based keyboards"
+	depends on HID
+	default !EXPERT
+	---help---
+    Support for Microdia devices that are not compliant with the HID standard.
+
+    One known example if the Redragon Asura Keyboard.
+
 config HID_MICROSOFT
 	tristate "Microsoft non-fully HID-compliant devices"
 	depends on HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 235bd2a7b333..e66a305876c5 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -62,6 +62,7 @@  obj-$(CONFIG_HID_LOGITECH_DJ)	+= hid-logitech-dj.o
 obj-$(CONFIG_HID_LOGITECH_HIDPP)	+= hid-logitech-hidpp.o
 obj-$(CONFIG_HID_MAGICMOUSE)	+= hid-magicmouse.o
 obj-$(CONFIG_HID_MAYFLASH)	+= hid-mf.o
+obj-$(CONFIG_HID_MICRODIA)  += hid-microdia.o
 obj-$(CONFIG_HID_MICROSOFT)	+= hid-microsoft.o
 obj-$(CONFIG_HID_MONTEREY)	+= hid-monterey.o
 obj-$(CONFIG_HID_MULTITOUCH)	+= hid-multitouch.o
@@ -121,4 +122,3 @@  obj-$(CONFIG_USB_KBD)		+= usbhid/
 
 obj-$(CONFIG_I2C_HID)		+= i2c-hid/
 
-obj-$(CONFIG_INTEL_ISH_HID)	+= intel-ish-hid/
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 0c3f608131cf..b36c2df4b755 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -2393,6 +2393,9 @@  static const struct hid_device_id hid_have_special_driver[] = {
 #endif
 #if IS_ENABLED(CONFIG_HID_ZYDACRON)
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ZYDACRON, USB_DEVICE_ID_ZYDACRON_REMOTE_CONTROL) },
+#endif
+#if IS_ENABLED(CONFIG_HID_MICRODIA)
+	{ HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA,  USB_DEVICE_ID_REDRAGON_ASURA) },
 #endif
 	{ }
 };
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 5da3d6256d25..146869e55c5a 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -1171,4 +1171,7 @@ 
 #define USB_VENDOR_ID_UGTIZER			0x2179
 #define USB_DEVICE_ID_UGTIZER_TABLET_GP0610	0x0053
 
+#define USB_VENDOR_ID_MICRODIA          0x0c45
+#define USB_DEVICE_ID_REDRAGON_ASURA    0x760b
+
 #endif
diff --git a/drivers/hid/hid-microdia.c b/drivers/hid/hid-microdia.c
new file mode 100644
index 000000000000..f9d8de18a989
--- /dev/null
+++ b/drivers/hid/hid-microdia.c
@@ -0,0 +1,148 @@ 
+/*
+ *  HID driver for Microdia-based keyboards
+ *
+ *  Copyright (c) 2017 Robert Munteanu
+ */
+
+/*
+ * 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.
+ */
+
+#include <linux/device.h>
+#include <linux/input.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+#include <linux/log2.h>
+#include <linux/input-event-codes.h>
+
+#include "hid-ids.h"
+
+
+// The microdia family of keyboards uses a non-standard way of sending
+// modifier keys
+//
+// The down event always sets the first bit to 0x04 and the second keycode
+// to a custom value. For instance, left shift sends the following bits
+//
+//   04 02 00 00 00 00 00 00
+//
+// while left control sends
+//
+//   04 01 00 00 00 00 00 00
+//
+// Unfortunately these are all mapped to left shift and the keyboard is
+// non-functional in that respect. To solve the problem, we capture the
+// raw data in raw_event and manually generate the correct input events
+//
+// TODO
+//
+// 1. Some modifiers keys still don't work, e.g. Ctrl-Shift-P
+//    Interestingly enough, this happens when pressing the physical
+//    left shift key, but now when pressing the physical right shift key.
+//    hexdump does not show them either.
+// 2. A second USB keyboard is registered, but it should be removed
+// 3. Modifier keys sometimes get stuck, need to re-press to clear
+
+static int microdia_input_configured(struct hid_device *hdev,
+	struct hid_input *hi)
+{
+
+	hid_info(hdev, "Keyboard configured with limited support (modifier keys may get stuck, some modifiers combinations with left-shift not working) ");
+
+	hid_set_drvdata(hdev, hi);
+
+	return 0;
+}
+
+static int microdia_input_mapping(struct hid_device *hdev, struct hid_input *hi,
+		struct hid_field *field, struct hid_usage *usage,
+		unsigned long **bit, int *max)
+{
+	// do not map left shift since we will manually generate input
+	// events in microdia_raw_event
+	if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD)
+		if ((usage->hid & HID_USAGE) == 0xe1)
+			return -1;
+
+	return 0;
+}
+
+// array index of a modifier matches the bit index in the data payload
+// the modifier data is always stored in the second int
+// e.g. for left alt the 1 bit is set - 04 04 ...
+// TODO - second entry should be left shift, but that's not possible
+// since we ignore it in the mapping
+static int microdia_modifiers[7] = {
+		KEY_LEFTCTRL,
+		KEY_RIGHTSHIFT,
+		KEY_LEFTALT,
+		KEY_LEFTMETA,
+		KEY_RIGHTCTRL,
+		KEY_RIGHTSHIFT,
+		KEY_RIGHTALT
+};
+
+static int microdia_last_handled_modifier;
+
+static int microdia_raw_event(struct hid_device *hdev,
+		struct hid_report *report, u8 *data, int size)
+{
+	int i, changed_key, new_value, mapped_key;
+	struct hid_input *hi;
+
+	// 1. validate that we get 8 bits of the for 04 xx 00 00 00 00 00 00
+	if (size != 8)
+		return 0;
+
+	if (data[0] != 4)
+		return 0;
+
+	// TODO - can I somehow use a bit mask? data & 0x00ffffff != 0
+	for (i = 2; i < size; i++)
+		if (data[i] != 0)
+			return 0;
+
+	// TODO - don't process the keyup event 04 00 00 00 00 00 00 00
+	// if we don't expect a modifier key 'up' event
+
+	// 2. detect based on previous data what key was pressed or depressed
+	// a key was pressed or depressed if its bit has a different value
+	// between this and the previous invocation. If the bit is set
+	// it was pressed
+
+	changed_key = data[1] ^ microdia_last_handled_modifier;
+	new_value = (data[1] & changed_key) != 0;
+	// TODO - is ilog2 really needed?
+	mapped_key = microdia_modifiers[ilog2(changed_key)];
+
+	// 3. report the key event and track what was sent
+	hi = hid_get_drvdata(hdev);
+
+	input_report_key(hi->input, mapped_key, new_value);
+
+	microdia_last_handled_modifier = data[1];
+
+	return 1;
+}
+
+static const struct hid_device_id microdia_devices[] = {
+	{HID_USB_DEVICE(USB_VENDOR_ID_MICRODIA, USB_DEVICE_ID_REDRAGON_ASURA)},
+	{}
+};
+
+MODULE_DEVICE_TABLE(hid, microdia_devices);
+
+static struct hid_driver microdia_driver = {
+	.name = "microdia",
+	.input_mapping = microdia_input_mapping,
+	.id_table = microdia_devices,
+	.raw_event = microdia_raw_event,
+	.input_configured = microdia_input_configured,
+};
+
+module_hid_driver(microdia_driver);
+
+MODULE_LICENSE("GPL");