From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roger Quadros Date: Thu, 11 Jul 2013 17:23:40 +0300 Subject: [U-Boot] [[PATCH v2 5/6] USB: ehci: Add a weak function for resetting devices In-Reply-To: <201307111435.32813.marex@denx.de> References: <1373486709-13015-1-git-send-email-dmurphy@ti.com> <51DDEB31.40806@ti.com> <51DE68A0.5080302@ti.com> <201307111435.32813.marex@denx.de> Message-ID: <51DEBFEC.60408@ti.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Marek, On 07/11/2013 03:35 PM, Marek Vasut wrote: > Dear Roger Quadros, > >> On 07/11/2013 02:16 AM, Dan Murphy wrote: >>> On 07/10/2013 05:20 PM, Marek Vasut wrote: >>>> Dear Dan Murphy, >>>> >>>>> Add a __weak function that can be overridden to reset devices >>>>> attached to an ehci devices after the FEAT_POWER has been submitted >>>>> >>>>> Signed-off-by: Dan Murphy >>>>> --- >>>>> >>>>> drivers/usb/host/ehci-hcd.c | 7 +++++++ >>>>> 1 file changed, 7 insertions(+) >>>>> >>>>> diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c >>>>> index 706cf0c..fdd3994 100644 >>>>> --- a/drivers/usb/host/ehci-hcd.c >>>>> +++ b/drivers/usb/host/ehci-hcd.c >>>>> @@ -616,6 +616,11 @@ __weak uint32_t *ehci_get_portsc_register(struct >>>>> ehci_hcor *hcor, int port) return (uint32_t *)&hcor->or_portsc[port]; >>>>> >>>>> } >>>>> >>>>> +__weak void ehci_reset_attached_devices(int port) >>>>> +{ >>>>> + return; >>>>> +} >> >> Does this function need to be ehci specific? Other USB controllers might >> also need such a function. > > You'd need to implement this for each of the xHCIs OK. > >>>>> + >>>> >>>> Can the reset not happen elsewhere? >>> >>> I have tried to move this around and keep this out of this file >>> completely but nothing else seems to work. >>> >>> For port 2 where the USB3530 is we don't have the issue the 3530 >>> enumerates properly. >>> >>> I did not see any information in the data sheet eluding to a timing >>> issue. >> >> This is the information I had received earlier from SMSC about USB3503A hub >> >> "You need the host up and running, and ready to go, THEN negate RESET_N. >> That is probably 95% of the issues." >> >> Please make sure the following sequence is done. >> >> - power up hub (RESET is active at this point). >> - start USB controller >> - wait a few ms >> - release hub RESET. >> >> giving a quick look at the u-boot code it seems you need to release the hub >> reset after usb_lowlevel_init() _OR_ usb_init() returns. > > Then it would also work in usb_lowlevel_init() ? It should as long as we place the "release reset" after EHCI controller has started. Maybe safer to put it in the end of usb_lowlevel_init(). cheers, -roger