Subject: Re: [PATCH V2 5/5] usb: serial: f81534: fix tx error on some baud
 rate
To: Johan Hovold <johan@kernel.org>
Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, peter_hong@fintek.com.tw,
        "Ji-Ze Hong (Peter Hong)" <hpeter+linux_kernel@gmail.com>
References: <1515032961-29131-1-git-send-email-hpeter+linux_kernel@gmail.com>
 <1515032961-29131-5-git-send-email-hpeter+linux_kernel@gmail.com>
 <20180109113216.GR11344@localhost>
From: "Ji-Ze Hong (Peter Hong)" <hpeter@gmail.com>
Message-ID: <747ab8c9-50cc-2bbb-6f58-758e3361cbe2@gmail.com>
Date: Wed, 10 Jan 2018 13:42:32 +0800
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Hi Johan,

Johan Hovold 於 2018/1/9 下午 07:32 寫道:
> On Thu, Jan 04, 2018 at 10:29:21AM +0800, Ji-Ze Hong (Peter Hong) wrote:
>> +	/*
>> +	 * We'll make tx frame error when baud rate from 384~500kps. So we'll
>> +	 * delay all tx data frame with 1bit.
>> +	 */
>> +	port_priv->shadow_clk |= F81534_CLK_TX_DELAY_1BIT;
> 
> You don't wan't to enable this only for the affected rates?
> 

This bit will control all transmit TX frame always delay 1 bit
on enabled, but It'll transmit TX frame randomly delay 1 bit on
disabled.

We had tested it with BurnInTest to check the performance,
It'll not make the performance regression. So we'll directly add
it on all baud rate.

Thanks
-- 
With Best Regards,
Peter Hong