From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Tomoya MORINAGA" <tomoya-linux-ECg8zkTtlr0C6LszWs/t0g@public.gmane.org>
Subject: Re: [PATCH net-next-2.6 v3] can: Topcliff: PCH_CAN driver: Add Flow
	control,
Date: Mon, 22 Nov 2010 14:05:52 +0900
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To: "Marc Kleine-Budde" <mkl-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
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On Friday, November 19, 2010 6:20 PM,  Marc Kleine-Budde wrote :

>>>> - spin_unlock_irqrestore(&priv->msgif_reg_lock, flags);
>>>> + pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
>>> Still we have the busy waiting in the TX path. Maybe you can move the
>>> waiting before accessing the if[1] and remove the busy waiting here.
>> I can't understand your saying.
>> For transmitting data, calling pch_can_rw_msg_obj is mandatory.
>Yes, but the busy wait is not needed. It should be enough to do the
>busy-waiting _before_ accessing the if[1].

Do you mean we should create other pch_can_rw_msg_obj which doesn't have busy wait ?

---
Thanks,

Tomoya MORINAGA
OKI SEMICONDUCTOR CO., LTD.