[PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Dmytro Bagrii]

This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.

CH341A has three different modes of operation selectable either by
hardware pin connections or by external EEPROM configuration. Each
mode is represented by corresponding product ID:

0x5523: Asyncronous Serial Interface
0x5584: Parallel Printer Interface
0x5512: EPP/MEM Interface

(See "5.3.Function configuration" in datasheet at wch-ic.com/downloads/CH341DS1_PDF.html)

When CH341A is configured as EPP/MEM Interface it appears as 1a86:5512 and being mistakenly
handled by ch341 USB serial driver.

It is possible to use CH341A in EPP/MEM mode only if ch341 module is blacklisted, but it must be
unblacklisted every time to use CH341A as a serial converter. Also obviously it is impossible
to use two CH341A boards in different modes simoultaneously.

Signed-off-by: Dmytro Bagrii <dimich.dmb@gmail.com>
---
 drivers/usb/serial/ch341.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 29f4b87a9e74..65f1286f7905 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -81,7 +81,6 @@
 #define CH341_QUIRK_SIMULATE_BREAK	BIT(1)
 
 static const struct usb_device_id id_table[] = {
-	{ USB_DEVICE(0x1a86, 0x5512) },
 	{ USB_DEVICE(0x1a86, 0x5523) },
 	{ USB_DEVICE(0x1a86, 0x7522) },
 	{ USB_DEVICE(0x1a86, 0x7523) },
-- 
2.35.1

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Greg KH]

On Mon, Feb 07, 2022 at 02:08:23AM +0200, Dmytro Bagrii wrote:
> This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.

You forgot to cc: the author of that commit, why?

Also forgot to cc: the maintainer of the driver/subsytem?

> CH341A has three different modes of operation selectable either by
> hardware pin connections or by external EEPROM configuration. Each
> mode is represented by corresponding product ID:
> 
> 0x5523: Asyncronous Serial Interface
> 0x5584: Parallel Printer Interface
> 0x5512: EPP/MEM Interface

That does not corrispond with what Jan-Niklas said in the original
commit.

> 
> (See "5.3.Function configuration" in datasheet at wch-ic.com/downloads/CH341DS1_PDF.html)
> 
> When CH341A is configured as EPP/MEM Interface it appears as 1a86:5512 and being mistakenly
> handled by ch341 USB serial driver.
> 
> It is possible to use CH341A in EPP/MEM mode only if ch341 module is blacklisted, but it must be
> unblacklisted every time to use CH341A as a serial converter. Also obviously it is impossible
> to use two CH341A boards in different modes simoultaneously.

Please wrap your lines at 72 columns.

thanks,

greg k-h

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Dmytro Bagrii]

On 08.02.22 12:34, Greg KH wrote:
> On Mon, Feb 07, 2022 at 02:08:23AM +0200, Dmytro Bagrii wrote:
>> This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.
> 
> You forgot to cc: the author of that commit, why?
> 
> Also forgot to cc: the maintainer of the driver/subsytem?

Sorry, forgot to add them. Also adding Johan Hovold, Frank A Kingswood 
and Frank Zago in the loop.

>> CH341A has three different modes of operation selectable either by
>> hardware pin connections or by external EEPROM configuration. Each
>> mode is represented by corresponding product ID:
>>
>> 0x5523: Asyncronous Serial Interface
>> 0x5584: Parallel Printer Interface
>> 0x5512: EPP/MEM Interface
> 
> That does not corrispond with what Jan-Niklas said in the original
> commit.

The page mentioned in the original commit is unavailable for me for some 
reason.

I refer to the chip manufacturer documentation from here: 
http://wch-ic.com/downloads/CH341DS1_PDF.html.

I have this kind of CH341A programmer: 
http://www.chinalctech.com/cpzx/Programmer/Serial_Module/266.html

When mode selection jumper is set to UART:

[52206.834474] usb 1-4.1: new full-speed USB device number 10 using xhci_hcd
[52206.925482] usb 1-4.1: New USB device found, idVendor=1a86, 
idProduct=5523, bcdDevice= 3.04
[52206.925494] usb 1-4.1: New USB device strings: Mfr=0, Product=0, 
SerialNumber=0
[52206.973701] usbcore: registered new interface driver ch341
[52206.973710] usbserial: USB Serial support registered for ch341-uart
[52206.973720] ch341 1-4.1:1.0: ch341-uart converter detected
[52206.974424] usb 1-4.1: ch341-uart converter now attached to ttyUSB0

ch341 creates /dev/ttyUSB0 and it works as a serial port, as expected.

When mode selection jumper is set to I2C/SPI (it uses EPP/MEM Interface):

[52413.942116] usb 1-4.1: new full-speed USB device number 11 using xhci_hcd
[52414.033085] usb 1-4.1: New USB device found, idVendor=1a86, 
idProduct=5512, bcdDevice= 3.04
[52414.033097] usb 1-4.1: New USB device strings: Mfr=0, Product=0, 
SerialNumber=0
[52414.040928] ch341 1-4.1:1.0: ch341-uart converter detected
[52414.041930] usb 1-4.1: ch341-uart converter now attached to ttyUSB0

ch341 creates /dev/ttyUSB0 but it doesn't work.

To use CH341A programmer as I2C/SPI converter either external module is 
required or userspace tools must be used. But they don't work until 
ch341 handles 1a86:5512.

If unbind device from ch341 module:

# echo 1-4.1:1.0 > /sys/bus/usb/drivers/ch341/unbind

I2C/SPI tools start to work correctly.

>> (See "5.3.Function configuration" in datasheet at wch-ic.com/downloads/CH341DS1_PDF.html)
>>
>> When CH341A is configured as EPP/MEM Interface it appears as 1a86:5512 and being mistakenly
>> handled by ch341 USB serial driver.
>>
>> It is possible to use CH341A in EPP/MEM mode only if ch341 module is blacklisted, but it must be
>> unblacklisted every time to use CH341A as a serial converter. Also obviously it is impossible
>> to use two CH341A boards in different modes simoultaneously.
> 
> Please wrap your lines at 72 columns.

Sure. Should i submit new patch verіon then?

> thanks,
> 
> greg k-h

-dmytro

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Johan Hovold]

On Tue, Feb 08, 2022 at 03:34:19PM +0200, Dmytro Bagrii wrote:
> On 08.02.22 12:34, Greg KH wrote:
> > On Mon, Feb 07, 2022 at 02:08:23AM +0200, Dmytro Bagrii wrote:
> >> This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.

> >> CH341A has three different modes of operation selectable either by
> >> hardware pin connections or by external EEPROM configuration. Each
> >> mode is represented by corresponding product ID:
> >>
> >> 0x5523: Asyncronous Serial Interface
> >> 0x5584: Parallel Printer Interface
> >> 0x5512: EPP/MEM Interface
> > 
> > That does not corrispond with what Jan-Niklas said in the original
> > commit.
> 
> The page mentioned in the original commit is unavailable for me for some 
> reason.
> 
> I refer to the chip manufacturer documentation from here: 
> http://wch-ic.com/downloads/CH341DS1_PDF.html.
> 
> I have this kind of CH341A programmer: 
> http://www.chinalctech.com/cpzx/Programmer/Serial_Module/266.html
> 
> When mode selection jumper is set to UART:
> 
> [52206.834474] usb 1-4.1: new full-speed USB device number 10 using xhci_hcd
> [52206.925482] usb 1-4.1: New USB device found, idVendor=1a86, 
> idProduct=5523, bcdDevice= 3.04
> [52206.925494] usb 1-4.1: New USB device strings: Mfr=0, Product=0, 
> SerialNumber=0
> [52206.973701] usbcore: registered new interface driver ch341
> [52206.973710] usbserial: USB Serial support registered for ch341-uart
> [52206.973720] ch341 1-4.1:1.0: ch341-uart converter detected
> [52206.974424] usb 1-4.1: ch341-uart converter now attached to ttyUSB0
> 
> ch341 creates /dev/ttyUSB0 and it works as a serial port, as expected.
> 
> When mode selection jumper is set to I2C/SPI (it uses EPP/MEM Interface):
> 
> [52413.942116] usb 1-4.1: new full-speed USB device number 11 using xhci_hcd
> [52414.033085] usb 1-4.1: New USB device found, idVendor=1a86, 
> idProduct=5512, bcdDevice= 3.04
> [52414.033097] usb 1-4.1: New USB device strings: Mfr=0, Product=0, 
> SerialNumber=0
> [52414.040928] ch341 1-4.1:1.0: ch341-uart converter detected
> [52414.041930] usb 1-4.1: ch341-uart converter now attached to ttyUSB0
> 
> ch341 creates /dev/ttyUSB0 but it doesn't work.
> 
> To use CH341A programmer as I2C/SPI converter either external module is 
> required or userspace tools must be used. But they don't work until 
> ch341 handles 1a86:5512.
> 
> If unbind device from ch341 module:
> 
> # echo 1-4.1:1.0 > /sys/bus/usb/drivers/ch341/unbind
> 
> I2C/SPI tools start to work correctly.
> 
> >> (See "5.3.Function configuration" in datasheet at wch-ic.com/downloads/CH341DS1_PDF.html)
> >>
> >> When CH341A is configured as EPP/MEM Interface it appears as 1a86:5512 and being mistakenly
> >> handled by ch341 USB serial driver.
> >>
> >> It is possible to use CH341A in EPP/MEM mode only if ch341 module is blacklisted, but it must be
> >> unblacklisted every time to use CH341A as a serial converter. Also obviously it is impossible
> >> to use two CH341A boards in different modes simoultaneously.
> > 
> > Please wrap your lines at 72 columns.
> 
> Sure. Should i submit new patch verіon then?

Please do so. But make sure you read this thread first if you haven't
already:

	https://lore.kernel.org/r/YJ0OCS/sh+1ifD/q@hovoldconsulting.com

I don't remember all the details, but judging from a quick look it seems
we're just waiting for someone to resend the revert with a proper
explanation.

It would be good if Jan-Niklas could chime in too and confirm if he's
able to use the device in UART mode instead.

Johan

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Jan-Niklas Burfeind]

I'm sorry, I did not notice this earlier;
will look into it tomorrow morning.

Thanks
Jan-Niklas Burfeind

On 2/9/22 15:18, Johan Hovold wrote:

> 
> It would be good if Jan-Niklas could chime in too and confirm if he's
> able to use the device in UART mode instead.
> 
> Johan

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Dmytro Bagrii]

On 09.02.22 16:18, Johan Hovold wrote:
> On Tue, Feb 08, 2022 at 03:34:19PM +0200, Dmytro Bagrii wrote:
>> On 08.02.22 12:34, Greg KH wrote:
>>> On Mon, Feb 07, 2022 at 02:08:23AM +0200, Dmytro Bagrii wrote:
>>>> This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.
> 
>>>> CH341A has three different modes of operation selectable either by
>>>> hardware pin connections or by external EEPROM configuration. Each
>>>> mode is represented by corresponding product ID:
>>>>
>>>> 0x5523: Asyncronous Serial Interface
>>>> 0x5584: Parallel Printer Interface
>>>> 0x5512: EPP/MEM Interface
>>>
>>> That does not corrispond with what Jan-Niklas said in the original
>>> commit.
>>
>> The page mentioned in the original commit is unavailable for me for some 
>> reason.
>>
>> I refer to the chip manufacturer documentation from here: 
>> http://wch-ic.com/downloads/CH341DS1_PDF.html.
>>
>> I have this kind of CH341A programmer: 
>> http://www.chinalctech.com/cpzx/Programmer/Serial_Module/266.html
>>
>> When mode selection jumper is set to UART:
>>
>> [52206.834474] usb 1-4.1: new full-speed USB device number 10 using xhci_hcd
>> [52206.925482] usb 1-4.1: New USB device found, idVendor=1a86, 
>> idProduct=5523, bcdDevice= 3.04
>> [52206.925494] usb 1-4.1: New USB device strings: Mfr=0, Product=0, 
>> SerialNumber=0
>> [52206.973701] usbcore: registered new interface driver ch341
>> [52206.973710] usbserial: USB Serial support registered for ch341-uart
>> [52206.973720] ch341 1-4.1:1.0: ch341-uart converter detected
>> [52206.974424] usb 1-4.1: ch341-uart converter now attached to ttyUSB0
>>
>> ch341 creates /dev/ttyUSB0 and it works as a serial port, as expected.
>>
>> When mode selection jumper is set to I2C/SPI (it uses EPP/MEM Interface):
>>
>> [52413.942116] usb 1-4.1: new full-speed USB device number 11 using xhci_hcd
>> [52414.033085] usb 1-4.1: New USB device found, idVendor=1a86, 
>> idProduct=5512, bcdDevice= 3.04
>> [52414.033097] usb 1-4.1: New USB device strings: Mfr=0, Product=0, 
>> SerialNumber=0
>> [52414.040928] ch341 1-4.1:1.0: ch341-uart converter detected
>> [52414.041930] usb 1-4.1: ch341-uart converter now attached to ttyUSB0
>>
>> ch341 creates /dev/ttyUSB0 but it doesn't work.
>>
>> To use CH341A programmer as I2C/SPI converter either external module is 
>> required or userspace tools must be used. But they don't work until 
>> ch341 handles 1a86:5512.
>>
>> If unbind device from ch341 module:
>>
>> # echo 1-4.1:1.0 > /sys/bus/usb/drivers/ch341/unbind
>>
>> I2C/SPI tools start to work correctly.
>>
>>>> (See "5.3.Function configuration" in datasheet at wch-ic.com/downloads/CH341DS1_PDF.html)
>>>>
>>>> When CH341A is configured as EPP/MEM Interface it appears as 1a86:5512 and being mistakenly
>>>> handled by ch341 USB serial driver.
>>>>
>>>> It is possible to use CH341A in EPP/MEM mode only if ch341 module is blacklisted, but it must be
>>>> unblacklisted every time to use CH341A as a serial converter. Also obviously it is impossible
>>>> to use two CH341A boards in different modes simoultaneously.
>>>
>>> Please wrap your lines at 72 columns.
>>
>> Sure. Should i submit new patch verіon then?
> 
> Please do so. But make sure you read this thread first if you haven't
> already:
> 
> 	https://lore.kernel.org/r/YJ0OCS/sh+1ifD/q@hovoldconsulting.com

Thanks. After i saw this patch i figured it out to remove and blacklist 
ch341 module to get CH341A working as I2C/SPI converter with i2c-ch341 
and spi-ch341-usb drivers.

I can confirm, CH341A works as serial converter with ch341 driver when it 
is configured as UART and has PID 5523. It can't work as I2C/SPI converter 
when configured as I2C/SPI and has PID5512 unless ch341 module is removed 
and blacklisted.

> I don't remember all the details, but judging from a quick look it seems
> we're just waiting for someone to resend the revert with a proper
> explanation.
> 
> It would be good if Jan-Niklas could chime in too and confirm if he's
> able to use the device in UART mode instead.

I'd like to take a look at that keeyees device from original commit 
message to see if it has EEPROM chip. I can hypothesize that some 
manufacturer of a CH341-based programmer could use external configuration 
EEPROM and mixed-up PID value. I haven't experiment with configuring 
CH341A with EEPROM but suppose it's possible to burn any custom VID:PID 
there. I don't think ch341 driver has to handle any of such custom 
VID/PID, especially if it conflicts with an original VID/PID assigned by 
chip manufacturer. In case of some peculiar devices it's possible to bind 
custom VID:PID to the driver via sysfs.

But it's just my hypothetical assumption how ch341-based device with PID 
5512 could work as UART in that case.

I just checked if CH341 that i have can work as UART when configured as 
I2C/SPI (PID 5512). I doesn't work: no output signal on TX pin, no 
loopback echo when RX connected to self TX.

-- 
Best Regards,
Dmytro Bagrii.

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Johan Hovold]

On Thu, Feb 10, 2022 at 07:41:22AM +0200, Dmytro Bagrii wrote:
> On 09.02.22 16:18, Johan Hovold wrote:

> > I don't remember all the details, but judging from a quick look it seems
> > we're just waiting for someone to resend the revert with a proper
> > explanation.
> > 
> > It would be good if Jan-Niklas could chime in too and confirm if he's
> > able to use the device in UART mode instead.
> 
> I'd like to take a look at that keeyees device from original commit 
> message to see if it has EEPROM chip. I can hypothesize that some 
> manufacturer of a CH341-based programmer could use external configuration 
> EEPROM and mixed-up PID value. I haven't experiment with configuring 
> CH341A with EEPROM but suppose it's possible to burn any custom VID:PID 
> there. I don't think ch341 driver has to handle any of such custom 
> VID/PID, especially if it conflicts with an original VID/PID assigned by 
> chip manufacturer. In case of some peculiar devices it's possible to bind 
> custom VID:PID to the driver via sysfs.
> 
> But it's just my hypothetical assumption how ch341-based device with PID 
> 5512 could work as UART in that case.
> 
> I just checked if CH341 that i have can work as UART when configured as 
> I2C/SPI (PID 5512). I doesn't work: no output signal on TX pin, no 
> loopback echo when RX connected to self TX.

Thanks for confirming.

Johan

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Jan-Niklas Burfeind]

Hello everyone.

For now I can identify two different USB-IDs depending on the Jumper 
position on the board:

1-2 connected: idVendor=1a86, idProduct=5512
2-3 or none  : idVendor=1a86, idProduct=5523

I'm not sure how I'd plug it to reach the Parallel Printer Interface 
mentioned before.

The advertised position of this Jumper is 1-2.
Both positions are labeled with two different chinese symbols, "2-3" is 
labeled with TTL as well.

Looking at the devices schematics I think its safe to revert my original 
commit and I'm sorry to have caused you all this trouble.

At the time I added the device I missidentified the Jumper as voltage 
level selector.

I had seen others using the board on youtube, with Jumper position 1-2;
and did not understand, why my system would not recognize it at all.


Sorry again and thanks for the effort
Jan-Niklas


On 2/9/22 15:18, Johan Hovold wrote:
> On Tue, Feb 08, 2022 at 03:34:19PM +0200, Dmytro Bagrii wrote:
>> On 08.02.22 12:34, Greg KH wrote:
>>> On Mon, Feb 07, 2022 at 02:08:23AM +0200, Dmytro Bagrii wrote:
>>>> This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.
> 
>>>> CH341A has three different modes of operation selectable either by
>>>> hardware pin connections or by external EEPROM configuration. Each
>>>> mode is represented by corresponding product ID:
>>>>
>>>> 0x5523: Asyncronous Serial Interface
>>>> 0x5584: Parallel Printer Interface
>>>> 0x5512: EPP/MEM Interface
>>>
>>> That does not corrispond with what Jan-Niklas said in the original
>>> commit.
>>
>> The page mentioned in the original commit is unavailable for me for some
>> reason.
>>
>> I refer to the chip manufacturer documentation from here:
>> http://wch-ic.com/downloads/CH341DS1_PDF.html.
>>
>> I have this kind of CH341A programmer:
>> http://www.chinalctech.com/cpzx/Programmer/Serial_Module/266.html
>>
>> When mode selection jumper is set to UART:
>>
>> [52206.834474] usb 1-4.1: new full-speed USB device number 10 using xhci_hcd
>> [52206.925482] usb 1-4.1: New USB device found, idVendor=1a86,
>> idProduct=5523, bcdDevice= 3.04
>> [52206.925494] usb 1-4.1: New USB device strings: Mfr=0, Product=0,
>> SerialNumber=0
>> [52206.973701] usbcore: registered new interface driver ch341
>> [52206.973710] usbserial: USB Serial support registered for ch341-uart
>> [52206.973720] ch341 1-4.1:1.0: ch341-uart converter detected
>> [52206.974424] usb 1-4.1: ch341-uart converter now attached to ttyUSB0
>>
>> ch341 creates /dev/ttyUSB0 and it works as a serial port, as expected.
>>
>> When mode selection jumper is set to I2C/SPI (it uses EPP/MEM Interface):
>>
>> [52413.942116] usb 1-4.1: new full-speed USB device number 11 using xhci_hcd
>> [52414.033085] usb 1-4.1: New USB device found, idVendor=1a86,
>> idProduct=5512, bcdDevice= 3.04
>> [52414.033097] usb 1-4.1: New USB device strings: Mfr=0, Product=0,
>> SerialNumber=0
>> [52414.040928] ch341 1-4.1:1.0: ch341-uart converter detected
>> [52414.041930] usb 1-4.1: ch341-uart converter now attached to ttyUSB0
>>
>> ch341 creates /dev/ttyUSB0 but it doesn't work.
>>
>> To use CH341A programmer as I2C/SPI converter either external module is
>> required or userspace tools must be used. But they don't work until
>> ch341 handles 1a86:5512.
>>
>> If unbind device from ch341 module:
>>
>> # echo 1-4.1:1.0 > /sys/bus/usb/drivers/ch341/unbind
>>
>> I2C/SPI tools start to work correctly.
>>
>>>> (See "5.3.Function configuration" in datasheet at wch-ic.com/downloads/CH341DS1_PDF.html)
>>>>
>>>> When CH341A is configured as EPP/MEM Interface it appears as 1a86:5512 and being mistakenly
>>>> handled by ch341 USB serial driver.
>>>>
>>>> It is possible to use CH341A in EPP/MEM mode only if ch341 module is blacklisted, but it must be
>>>> unblacklisted every time to use CH341A as a serial converter. Also obviously it is impossible
>>>> to use two CH341A boards in different modes simoultaneously.
>>>
>>> Please wrap your lines at 72 columns.
>>
>> Sure. Should i submit new patch verіon then?
> 
> Please do so. But make sure you read this thread first if you haven't
> already:
> 
> 	https://lore.kernel.org/r/YJ0OCS/sh+1ifD/q@hovoldconsulting.com
> 
> I don't remember all the details, but judging from a quick look it seems
> we're just waiting for someone to resend the revert with a proper
> explanation.
> 
> It would be good if Jan-Niklas could chime in too and confirm if he's
> able to use the device in UART mode instead.
> 
> Johan

Re: [PATCH] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Johan Hovold]

On Thu, Feb 10, 2022 at 11:18:22AM +0100, Jan-Niklas Burfeind wrote:
> Hello everyone.
> 
> For now I can identify two different USB-IDs depending on the Jumper 
> position on the board:
> 
> 1-2 connected: idVendor=1a86, idProduct=5512
> 2-3 or none  : idVendor=1a86, idProduct=5523
> 
> I'm not sure how I'd plug it to reach the Parallel Printer Interface 
> mentioned before.
> 
> The advertised position of this Jumper is 1-2.
> Both positions are labeled with two different chinese symbols, "2-3" is 
> labeled with TTL as well.
> 
> Looking at the devices schematics I think its safe to revert my original 
> commit and I'm sorry to have caused you all this trouble.
> 
> At the time I added the device I missidentified the Jumper as voltage 
> level selector.
> 
> I had seen others using the board on youtube, with Jumper position 1-2;
> and did not understand, why my system would not recognize it at all.
> 
> 
> Sorry again and thanks for the effort

No problem. Thanks for helping us clear this up.

Johan

[PATCH v2] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Dmytro Bagrii]

This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.

CH341 has Product ID 0x5512 in EPP/MEM mode which is used for
I2C/SPI/GPIO interfaces. In asynchronous serial interface mode
CH341 has PID 0x5523 which is already in the table.

Mode is selected by corresponding jumper setting.

Signed-off-by: Dmytro Bagrii <dimich.dmb@gmail.com>
---
 drivers/usb/serial/ch341.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 29f4b87a9e74..65f1286f7905 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -81,7 +81,6 @@
 #define CH341_QUIRK_SIMULATE_BREAK	BIT(1)
 
 static const struct usb_device_id id_table[] = {
-	{ USB_DEVICE(0x1a86, 0x5512) },
 	{ USB_DEVICE(0x1a86, 0x5523) },
 	{ USB_DEVICE(0x1a86, 0x7522) },
 	{ USB_DEVICE(0x1a86, 0x7523) },
-- 
2.35.1

Re: [PATCH v2] Revert "USB: serial: ch341: add new Product ID for CH341A"

[Johan Hovold]

On Thu, Feb 10, 2022 at 06:41:37PM +0200, Dmytro Bagrii wrote:
> This reverts commit 46ee4abb10a07bd8f8ce910ee6b4ae6a947d7f63.
> 
> CH341 has Product ID 0x5512 in EPP/MEM mode which is used for
> I2C/SPI/GPIO interfaces. In asynchronous serial interface mode
> CH341 has PID 0x5523 which is already in the table.
> 
> Mode is selected by corresponding jumper setting.
> 
> Signed-off-by: Dmytro Bagrii <dimich.dmb@gmail.com>

I was hoping for some more details in the commit message so we don't
have to dig out the information from long email-threads if this ever
comes up again. 

Well, well. I added links to the mail archives before applying.

Thanks!

Johan