Re: Nokia N900: musb is in wrong state after boot

[Bin Liu]

Hi,

On Sun, May 29, 2016 at 12:38:24PM +0200, Pali Rohár wrote:
> > Hello, attached patch for musb debugfs adds option to force both 
> > hostmode with speed. It is just example, I tested only compilation.
> > 
> > Something like that will be needed for usb host mode on Nokia N900.
> > 
> > -- 
> > Pali Rohár
> > pali.rohar@xxxxxxxxx
> 
> > From fd67b58e3538c0732750ecad915cde736da099dc Mon Sep 17 00:00:00 2001
> > From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali.rohar@xxxxxxxxx>
> > Date: Sat, 9 Jan 2016 16:57:59 +0100
> > Subject: [PATCH] musb: debugfs: Add support in testmode for forcing host mode
> >  together with speed
> > 
> > ---
> >  drivers/usb/musb/musb_debugfs.c |   44 +++++++++++++++++++++++++--------------
> >  1 file changed, 28 insertions(+), 16 deletions(-)
> > 
> > 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)
> >  
> >  	test = musb_readb(musb->mregs, MUSB_TESTMODE);
> >  
> > -	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");
> >  
> > -	if (test & MUSB_TEST_FIFO_ACCESS)
> > +	else if (test & MUSB_TEST_FIFO_ACCESS)
> >  		seq_printf(s, "fifo access\n");
> >  
> > -	if (test & MUSB_TEST_FORCE_FS)
> > +	else if (test & MUSB_TEST_FORCE_FS)
> >  		seq_printf(s, "force full-speed\n");
> >  
> > -	if (test & MUSB_TEST_FORCE_HS)
> > +	else if (test & MUSB_TEST_FORCE_HS)
> >  		seq_printf(s, "force high-speed\n");
> >  
> > -	if (test & MUSB_TEST_PACKET)
> > +	else if (test & MUSB_TEST_PACKET)
> >  		seq_printf(s, "test packet\n");
> >  
> > -	if (test & MUSB_TEST_K)
> > +	else if (test & MUSB_TEST_K)
> >  		seq_printf(s, "test K\n");
> >  
> > -	if (test & MUSB_TEST_J)
> > +	else if (test & MUSB_TEST_J)
> >  		seq_printf(s, "test J\n");
> >  
> > -	if (test & MUSB_TEST_SE0_NAK)
> > +	else if (test & MUSB_TEST_SE0_NAK)
> >  		seq_printf(s, "test SE0 NAK\n");
> >  
> >  	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;
> >  
> > -	if (strstarts(buf, "force host"))
> > +	if (strstarts(buf, "force host full-speed"))
> > +		test = MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS;
> > +
> > +	else if (strstarts(buf, "force host high-speed"))
> > +		test = MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_HS;
> > +
> > +	else if (strstarts(buf, "force host"))
> >  		test = MUSB_TEST_FORCE_HOST;
> >  
> > -	if (strstarts(buf, "fifo access"))
> > +	else if (strstarts(buf, "fifo access"))
> >  		test = MUSB_TEST_FIFO_ACCESS;
> >  
> > -	if (strstarts(buf, "force full-speed"))
> > +	else if (strstarts(buf, "force full-speed"))
> >  		test = MUSB_TEST_FORCE_FS;
> >  
> > -	if (strstarts(buf, "force high-speed"))
> > +	else if (strstarts(buf, "force high-speed"))
> >  		test = MUSB_TEST_FORCE_HS;
> >  
> > -	if (strstarts(buf, "test packet")) {
> > +	else if (strstarts(buf, "test packet")) {
> >  		test = MUSB_TEST_PACKET;
> >  		musb_load_testpacket(musb);
> >  	}
> >  
> > -	if (strstarts(buf, "test K"))
> > +	else if (strstarts(buf, "test K"))
> >  		test = MUSB_TEST_K;
> >  
> > -	if (strstarts(buf, "test J"))
> > +	else if (strstarts(buf, "test J"))
> >  		test = MUSB_TEST_J;
> >  
> > -	if (strstarts(buf, "test SE0 NAK"))
> > +	else if (strstarts(buf, "test SE0 NAK"))
> >  		test = MUSB_TEST_SE0_NAK;
> >  
> >  	musb_writeb(musb->mregs, MUSB_TESTMODE, test);
> > -- 
> > 1.7.9.5
> > 
> 
> Tony, what do you think about that patch?

Based on the musb ug, force_host bit is allowed to be set along with
force_hs or force_fs bit. So please resend this patch with subject
changed to the following, and I will take it. The current suject makes
is sound like a new feature rather than a bugfix.

"usb: musb: debugfs: allow forcing host mode together with speed in testmode"

But I am not sure how this will fix n900 host mode problem, since
testmode is not used in normal operation.

Regards,
-Bin.