From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Mack Subject: Re: [PATCH 1/5] usb: musb: conditionally save and restore the context on suspend Date: Mon, 25 Nov 2013 21:08:51 +0100 Message-ID: <5293AE53.9080606@gmail.com> References: <1385408393-19707-1-git-send-email-zonque@gmail.com> <1385408393-19707-2-git-send-email-zonque@gmail.com> <20131125194427.GZ18046@saruman.home> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from mail-bk0-f54.google.com ([209.85.214.54]:61260 "EHLO mail-bk0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753181Ab3KYUI5 (ORCPT ); Mon, 25 Nov 2013 15:08:57 -0500 In-Reply-To: <20131125194427.GZ18046@saruman.home> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: balbi@ti.com Cc: bigeasy@linutronix.de, linux-usb@vger.kernel.org, linux-omap@vger.kernel.org, neumann@teufel.de On 11/25/2013 08:44 PM, Felipe Balbi wrote: > Hi, > > On Mon, Nov 25, 2013 at 08:39:49PM +0100, Daniel Mack wrote: >> It appears not all platforms featuring a musb core need to save the musb >> core registers at suspend time and restore them on resume. >> >> The dsps platform does, however. So add a bit in struct >> musb_hdrc_platform_data to let platforms specify their need of such >> action being taken. >> >> Signed-off-by: Daniel Mack >> --- >> drivers/usb/musb/musb_core.c | 17 ++++++++++++++++- >> include/linux/usb/musb.h | 3 +++ >> 2 files changed, 19 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c >> index 0a43329..a8ded57 100644 >> --- a/drivers/usb/musb/musb_core.c >> +++ b/drivers/usb/musb/musb_core.c >> @@ -2202,6 +2202,7 @@ static int musb_suspend(struct device *dev) >> { >> struct musb *musb = dev_to_musb(dev); >> unsigned long flags; >> + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); > > we don't want to have platform_data on DT-based boot. It's best to just > save those registers unconditionally as it doesn't hurt. > My concern about doing it unconditionally from the core is simply that I fear regressions for other platforms. I can of course drop it if you're certain that that's correct. I can only test this on a dsps glue layer, and I have no documentation for the musb core. All I'm left with here is fishing in muddy waters :/ Daniel