Fwd: USB - Generic Serial device : Unable to read more than 4095 bytes

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Thank you for the reply

>> The tty layer is limiting you, just keep reading in a loop until you
>> run out of data, you should not ever expect to read a specific number of
>> bytes from a tty device at a time, the read call will tell you the
>> number that was read properly.

I tried this method but in my case I found data loss. By changing any
buffer size modification in driver side , can we fix this issue ?

>> Please don't use the "generic" driver, it's slow and not the best to
>> use

Could you tell me is generic driver is suitable for my application (
My usb device sending data at a rate of 409600 bytes/sec) , ?
or do you have any other suggestion for me ?

My Linux kernel  version is 3.4.35

Regards,
Arun

On Tue, Aug 4, 2015 at 1:13 AM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Mon, Aug 03, 2015 at 04:44:07PM +0900, arun k wrote:
> > Hi ,
> >
> > I have a trouble with using usb serial generic device.
> >  I am using USB - Generic Serial driver for communicating with my usb
> > device and my embedded device.
>
> Please don't use the "generic" driver, it's slow and not the best to
> use.
>
> > My usb device sending data at a rate of 409600 bytes/sec, and in host
> > side application I tried to read 16384 bytes in one read. But the read
> > size returning is always  4095
>
> The tty layer is limiting you, just keep reading in a loop until you
> run out of data, you should not ever expect to read a specific number of
> bytes from a tty device at a time, the read call will tell you the
> number that was read properly.
>
> thanks,
>
> greg k-h
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