From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964795AbcJYTQ6 (ORCPT ); Tue, 25 Oct 2016 15:16:58 -0400 Received: from vern.gendns.com ([206.190.152.46]:54838 "EHLO vern.gendns.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755016AbcJYTQ4 (ORCPT ); Tue, 25 Oct 2016 15:16:56 -0400 Subject: Re: [PATCH 2/3] phy: da8xx-usb: Configure CFGCHIP2 to support OTG workaround To: Alexandre Bailon , khilman@baylibre.com, b-liu@ti.com, balbi@kernel.org References: <1477403576-11825-1-git-send-email-abailon@baylibre.com> <1477403576-11825-3-git-send-email-abailon@baylibre.com> Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org From: David Lechner Message-ID: Date: Tue, 25 Oct 2016 14:16:55 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <1477403576-11825-3-git-send-email-abailon@baylibre.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - vern.gendns.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lechnology.com X-Get-Message-Sender-Via: vern.gendns.com: authenticated_id: davidmain+lechnology.com/only user confirmed/virtual account not confirmed X-Authenticated-Sender: vern.gendns.com: davidmain@lechnology.com X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/25/2016 08:52 AM, Alexandre Bailon wrote: > If we configure the da8xx OTG phy in OTG mode, neither device or host > mode will work. That is because the PHY is not able to detect and notify > the driver that value of ID pin changed. > To work despite this hardware limitation, the da8xx glue implement a > workaround. > But to work, the workaround require the VBUS sense and the session end > comparator to enabled. > Enable them if the phy is configured in OTG mode. > > Signed-off-by: Alexandre Bailon > --- > drivers/phy/phy-da8xx-usb.c | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/drivers/phy/phy-da8xx-usb.c b/drivers/phy/phy-da8xx-usb.c > index 32ae78c..fd39292 100644 > --- a/drivers/phy/phy-da8xx-usb.c > +++ b/drivers/phy/phy-da8xx-usb.c > @@ -93,24 +93,31 @@ static int da8xx_usb20_phy_power_off(struct phy *phy) > static int da8xx_usb20_phy_set_mode(struct phy *phy, enum phy_mode mode) > { > struct da8xx_usb_phy *d_phy = phy_get_drvdata(phy); > + int ret; > u32 val; > > + ret = regmap_read(d_phy->regmap, CFGCHIP(2), &val); > + if (ret) > + return ret; > + > + val &= ~CFGCHIP2_OTGMODE_MASK; > + > switch (mode) { > case PHY_MODE_USB_HOST: /* Force VBUS valid, ID = 0 */ > - val = CFGCHIP2_OTGMODE_FORCE_HOST; > + val |= CFGCHIP2_OTGMODE_FORCE_HOST; > break; > case PHY_MODE_USB_DEVICE: /* Force VBUS valid, ID = 1 */ > - val = CFGCHIP2_OTGMODE_FORCE_DEVICE; > + val |= CFGCHIP2_OTGMODE_FORCE_DEVICE; > break; > case PHY_MODE_USB_OTG: /* Don't override the VBUS/ID comparators */ > - val = CFGCHIP2_OTGMODE_NO_OVERRIDE; > + val |= CFGCHIP2_OTGMODE_NO_OVERRIDE | > + CFGCHIP2_SESENDEN | CFGCHIP2_VBDTCTEN; Do we need to clear CFGCHIP2_SESENDEN and/or CFGCHIP2_VBDTCTEN in case PHY_MODE_USB_HOST: or case PHY_MODE_USB_DEVICE:? Or are they ignored in those modes? > break; > default: > return -EINVAL; > } > > - regmap_write_bits(d_phy->regmap, CFGCHIP(2), CFGCHIP2_OTGMODE_MASK, > - val); > + regmap_write(d_phy->regmap, CFGCHIP(2), val); > > return 0; > } >