From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH 3/3] musb: AM35x: Workaround for fifo read issue Date: Tue, 18 May 2010 13:59:45 +0400 Message-ID: <4BF26511.2060705@ru.mvista.com> References: <1274093235-7616-1-git-send-email-ajay.gupta@ti.com> <1274093235-7616-2-git-send-email-ajay.gupta@ti.com> <1274093235-7616-3-git-send-email-ajay.gupta@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wy0-f174.google.com ([74.125.82.174]:57131 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752602Ab0ERKAh (ORCPT ); Tue, 18 May 2010 06:00:37 -0400 In-Reply-To: <1274093235-7616-3-git-send-email-ajay.gupta@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Ajay Kumar Gupta Cc: linux-usb@vger.kernel.org, linux-omap@vger.kernel.org, felipe.balbi@nokia.com Hello. Ajay Kumar Gupta wrote: > AM35x supports only 32bit read operations so we need to have > workaround for 8bit and 16bit read operations. > Signed-off-by: Ajay Kumar Gupta > --- > Patch created against linus'tree + all musb patches in Greg's queue > Changes from v2: > - fixed multipline comment style > drivers/usb/musb/am3517.c | 31 +++++++++++++++++++++++++++++++ > drivers/usb/musb/musb_core.c | 2 ++ > 2 files changed, 33 insertions(+), 0 deletions(-) > diff --git a/drivers/usb/musb/am3517.c b/drivers/usb/musb/am3517.c > index b74e664..c68c784 100644 > --- a/drivers/usb/musb/am3517.c > +++ b/drivers/usb/musb/am3517.c > @@ -515,3 +515,34 @@ void musb_platform_restore_context(struct musb_context_registers > phy_on(); > } > #endif > + > +/* AM35x supports only 32bit read operation */ > +void musb_read_fifo(struct musb_hw_ep *hw_ep, u16 len, u8 *dst) > +{ > + void __iomem *fifo = hw_ep->fifo; > + u32 val; > + int i; > + > + /* Read for 32bit-aligned destination address */ > + if ((likely((0x03 & (unsigned long) dst) == 0)) && len >= 4) { You don't need to put likely() in parens. > + readsl(fifo, dst, len >> 2); > + dst += (len & ~0x03); You don't need parens here as well. > + len &= 0x03; > + } > + /* > + * Now read the rest 1 to 3 bytes or complete length if > + * unaligned address. > + */ > + if (len > 4) { > + for (i = 0; i < (len >> 2); i++) { > + val = musb_readl(fifo, 0); > + memcpy(dst, &val, 4); Can't you do away with memcpy() here? > + dst += 4; > + } > + len %= 4; > + } > + if (len > 0) { > + val = musb_readl(fifo, 0); > + memcpy(dst, &val, len); > + } > +} WBR, Sergei