From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pali =?utf-8?B?Um9ow6Fy?= Subject: Re: Nokia N900: musb is in wrong state after boot Date: Sun, 29 May 2016 12:38:24 +0200 Message-ID: <20160529103824.GM29844@pali> References: <201601091616.04193@pali> <3690314.8jDXSUDcRZ@saturn> <20160121192113.GM19432@atomide.com> <201601231357.32629@pali> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <201601231357.32629@pali> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tony Lindgren Cc: joerg Reisenweber , Felipe Balbi , Greg Kroah-Hartman , linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ivaylo Dimitrov , Sebastian Reichel , Aaro Koskinen , Pavel Machek , Nishanth Menon List-Id: linux-omap@vger.kernel.org On Saturday 23 January 2016 13:57:32 Pali Roh=C3=A1r wrote: > On Thursday 21 January 2016 20:21:13 Tony Lindgren wrote: > > * joerg Reisenweber [160121 10:45]: > > > On Thu 21 January 2016 09:41:46 Tony Lindgren wrote: > > > > Then for supporting the USB host mode.. We should add regulator > > > > support to the USB PHY driver so if the ID pin is grounded, the > > > > PHY driver enables the VBUS regulator. That too seems to need > > > > some coordination between the drivers/phy/phy-twl4030-usb.c and > > > > 1707 driver if the ID pin interrupt is only detected in > > > > drivers/phy/phy-twl4030-usb.c. > > >=20 > > > Note that, while this is probably a good thing to do, it needs to > > > be sufficiently loose coupling to allow user to 'intercept' this > > > VBOOS regulator enabling and instead allow device charging while > > > in externally powered hostmode. There's even a spec for this in > > > USB-docs-foo iirc, something along a certain resistor value on ID > > > to GND - alas I guess the twl4030 is not capable to detect such > > > sophisticated signaling, and anyway it's always desirable to allo= w > > > user to manually override the VBOOST and enable VBUS-charging > > > while in hostmode. > >=20 > > OK, I think this is what's happening with the Motorola LapDock BTW. > > It always feeds the VBUS, well most of the time. Do you have some > > pointer to the "certain resistor value on ID to GND" spec? Is it > > maybe part of the carkit related parts of the USB spec? > >=20 > > > On N900 the situation is even more complex since the 1707 doesn't > > > support genuine ID detection, neither does it support emulated ID > > > grounding. And there's no other method than a ID=3DGND message fr= om > > > PHY to musb core to make the musb core state engine transfer into > > > proper hostmode. Thus my H-E-N hostmode botch abuses debug flags > > > to force the musb core into a "emulated" hostmode and this mode > > > doesn't support USB speed detection. Thus speed settings are > > > forced onto musb core and PHY by software, and the musb core spee= d > > > bits are only effective before session enabled. > > > Bottom line: you need VBUS to try and negotiate speed with the > > > attached device in hostmode, but to actually set this speed you > > > detected by software means, you need to disable and discharge VBU= S > > > again, or musb core won't care about the speed you set. To be > > > utterly clear: unconditional enabling of VBUS in ID=3DGND won't > > > work. > > >=20 > > > This is quite complex and it's questionable if it could get handl= ed > > > reasonably in kernel space. *Very* N900 specific niche solution, > > > I'd not think it's suited for upstreaming. > >=20 > > Yeah OK. I think we should be able to support the aux VBUS regulato= r > > part with mainline kernel though. > >=20 > > Regards, > >=20 > > Tony >=20 > Hello, attached patch for musb debugfs adds option to force both=20 > hostmode with speed. It is just example, I tested only compilation. >=20 > Something like that will be needed for usb host mode on Nokia N900. >=20 > --=20 > Pali Roh=C3=A1r > pali.rohar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org > From fd67b58e3538c0732750ecad915cde736da099dc Mon Sep 17 00:00:00 200= 1 > From: =3D?UTF-8?q?Pali=3D20Roh=3DC3=3DA1r?=3D > Date: Sat, 9 Jan 2016 16:57:59 +0100 > Subject: [PATCH] musb: debugfs: Add support in testmode for forcing h= ost mode > together with speed >=20 > --- > drivers/usb/musb/musb_debugfs.c | 44 +++++++++++++++++++++++++----= ---------- > 1 file changed, 28 insertions(+), 16 deletions(-) >=20 > diff --git a/drivers/usb/musb/musb_debugfs.c b/drivers/usb/musb/musb_= debugfs.c > index 9b22d94..62c13a2 100644 > --- a/drivers/usb/musb/musb_debugfs.c > +++ b/drivers/usb/musb/musb_debugfs.c > @@ -147,28 +147,34 @@ static int musb_test_mode_show(struct seq_file = *s, void *unused) > =20 > test =3D musb_readb(musb->mregs, MUSB_TESTMODE); > =20 > - if (test & MUSB_TEST_FORCE_HOST) > + if (test & (MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS)) > + seq_printf(s, "force host full-speed\n"); > + > + else if (test & (MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_HS)) > + seq_printf(s, "force host high-speed\n"); > + > + else if (test & MUSB_TEST_FORCE_HOST) > seq_printf(s, "force host\n"); > =20 > - if (test & MUSB_TEST_FIFO_ACCESS) > + else if (test & MUSB_TEST_FIFO_ACCESS) > seq_printf(s, "fifo access\n"); > =20 > - if (test & MUSB_TEST_FORCE_FS) > + else if (test & MUSB_TEST_FORCE_FS) > seq_printf(s, "force full-speed\n"); > =20 > - if (test & MUSB_TEST_FORCE_HS) > + else if (test & MUSB_TEST_FORCE_HS) > seq_printf(s, "force high-speed\n"); > =20 > - if (test & MUSB_TEST_PACKET) > + else if (test & MUSB_TEST_PACKET) > seq_printf(s, "test packet\n"); > =20 > - if (test & MUSB_TEST_K) > + else if (test & MUSB_TEST_K) > seq_printf(s, "test K\n"); > =20 > - if (test & MUSB_TEST_J) > + else if (test & MUSB_TEST_J) > seq_printf(s, "test J\n"); > =20 > - if (test & MUSB_TEST_SE0_NAK) > + else if (test & MUSB_TEST_SE0_NAK) > seq_printf(s, "test SE0 NAK\n"); > =20 > return 0; > @@ -206,30 +212,36 @@ static ssize_t musb_test_mode_write(struct file= *file, > if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)= )) > return -EFAULT; > =20 > - if (strstarts(buf, "force host")) > + if (strstarts(buf, "force host full-speed")) > + test =3D MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS; > + > + else if (strstarts(buf, "force host high-speed")) > + test =3D MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_HS; > + > + else if (strstarts(buf, "force host")) > test =3D MUSB_TEST_FORCE_HOST; > =20 > - if (strstarts(buf, "fifo access")) > + else if (strstarts(buf, "fifo access")) > test =3D MUSB_TEST_FIFO_ACCESS; > =20 > - if (strstarts(buf, "force full-speed")) > + else if (strstarts(buf, "force full-speed")) > test =3D MUSB_TEST_FORCE_FS; > =20 > - if (strstarts(buf, "force high-speed")) > + else if (strstarts(buf, "force high-speed")) > test =3D MUSB_TEST_FORCE_HS; > =20 > - if (strstarts(buf, "test packet")) { > + else if (strstarts(buf, "test packet")) { > test =3D MUSB_TEST_PACKET; > musb_load_testpacket(musb); > } > =20 > - if (strstarts(buf, "test K")) > + else if (strstarts(buf, "test K")) > test =3D MUSB_TEST_K; > =20 > - if (strstarts(buf, "test J")) > + else if (strstarts(buf, "test J")) > test =3D MUSB_TEST_J; > =20 > - if (strstarts(buf, "test SE0 NAK")) > + else if (strstarts(buf, "test SE0 NAK")) > test =3D MUSB_TEST_SE0_NAK; > =20 > musb_writeb(musb->mregs, MUSB_TESTMODE, test); > --=20 > 1.7.9.5 >=20 Tony, what do you think about that patch? --=20 Pali Roh=C3=A1r pali.rohar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html