From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko =?ISO-8859-1?Q?St=FCbner?= Subject: Re: [PATCH v5 2/2] phy: rockchip-inno-usb2: add a new driver for Rockchip usb2phy Date: Wed, 15 Jun 2016 20:49:30 +0200 Message-ID: <2590052.6LplKWTe68@diego> References: <1465783810-18756-1-git-send-email-frank.wang@rock-chips.com> <20086422.3ieDmpZrvB@diego> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Frank Wang Cc: dianders@chromium.org, linux@roeck-us.net, groeck@chromium.org, jwerner@chromium.org, kishon@ti.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-usb@vger.kernel.org, linux-rockchip@lists.infradead.org, xzy.xu@rock-chips.com, kever.yang@rock-chips.com, huangtao@rock-chips.com, william.wu@rock-chips.com List-Id: devicetree@vger.kernel.org Hi Frank, Am Mittwoch, 15. Juni 2016, 18:58:43 schrieb Frank Wang: > On 2016/6/15 17:04, Heiko St=FCbner wrote: > > Am Mittwoch, 15. Juni 2016, 11:23:26 schrieb Frank Wang: > >> On 2016/6/14 21:27, Heiko St=FCbner wrote: > >>> Am Montag, 13. Juni 2016, 10:10:10 schrieb Frank Wang: > >>>> The newer SoCs (rk3366, rk3399) take a different usb-phy IP bloc= k > >>>> than rk3288 and before, and most of phy-related registers are al= so > >>>> different from the past, so a new phy driver is required necessa= rily. > >>>>=20 > >>>> Signed-off-by: Frank Wang > >>>> --- > >>>>=20 > >>>> Changes in v5: > >>>> - Added 'reg' in the data block to match the different phy-bl= ocks in > >>>> dt. > >>>>=20 > >>>> Changes in v4: > >>>> - Removed some processes related to 'vbus_host-supply'. > >>>>=20 > >>>> Changes in v3: > >>>> - Resolved the mapping defect between fixed value in driver a= nd the > >>>>=20 > >>>> property in devicetree. > >>>>=20 > >>>> - Optimized 480m output clock register function. > >>>> - Code cleanup. > >>>>=20 > >>>> Changes in v2: > >>>> - Changed vbus_host operation from gpio to regulator in *_pro= be. > >>>> - Improved the fault treatment relate to 480m clock register. > >>>> - Cleaned up some meaningless codes in *_clk480m_disable. > >>>> - made more clear the comment of *_sm_work. > >>>> =20 > >>>> drivers/phy/Kconfig | 7 + > >>>> drivers/phy/Makefile | 1 + > >>>> drivers/phy/phy-rockchip-inno-usb2.c | 645 > >>>>=20 > >>>> ++++++++++++++++++++++++++++++++++ 3 files changed, 653 insertio= ns(+) > >>>>=20 > >>>> [...] > >>>>=20 > >>>> + > >>>> +static int rockchip_usb2phy_exit(struct phy *phy) > >>>> +{ > >>>> + struct rockchip_usb2phy_port *rport =3D phy_get_drvdata(phy); > >>>> + > >>>>=20 > >>> if (!rport->port_cfg) > >>> =09 > >>> return 0; > >>>>=20 > >>>> + if (rport->port_id =3D=3D USB2PHY_PORT_HOST) > >>>> + cancel_delayed_work_sync(&rport->sm_work); > >>>> + > >>>=20 > >>> you will also need to resume the port here, if it is suspended at= this > >>> point, as phy_power_off gets called after phy_exit and would prob= ably > >>> produce clk enable/disable mismatches otherwise. > >>=20 > >> Hmm, from my personal point of view, when canceling sm_work here, = it may > >> not cause the port goes to suspend, isn't it? besides, clk only pr= epared > >> in *_usb2phy_resume(), and unprepared in *_usb2phy_suspend(), so i= f we > >> resume port here, the prepare_count of clk will be increased agai= n, I > >> am afraid this is not correct, and am I wrong? would you like to t= ell me > >> more details? > >=20 > > usb2phy_resume gets called both initially through phy_power_on as w= ell. > > So it's on but through the first scheduled work call, might get sus= pended > > when nothing is connected. (clk_enable and clk_disable will run). > > If nothing is connected on unload phy_power_off will get called whi= le the > > clock actually is still disabled. > >=20 > > So I think it's either resuming on exit, or at least making sure to= do > > nothing in that case in the phy_power_off callback of the driver. >=20 > Well, I got what you mean. I saw phy_power_on() gets called twice at > ehci/ohci driver probe time, one is at pdata->power_on(); another is = at > usb_add_hcd(), so after that, the power_count of phy increases to two= =2E > however, when ehci/ohci driver goes to suspend, there is only once to > call phy_power_off(), and the power_count of phy decreases to 1, so o= ur > usb2phy_resume() could not be invoked :-) . > > If so, is it still need to care it? You should never have to rely on oddities in other drivers :-) > How about use suspended member of > rockchip_usb2phy_port as a conditional to check in *_usb2phy_suspend(= ), > if necessary. That looks also sane and should work. Heiko