Re: [PATCH] usb: musb: debugfs: allow forcing host mode together with speed in testmode

From: Bin Liu <b-liu@ti.com>
To: "Pali Rohár" <pali.rohar@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	<linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	Tony Lindgren <tony@atomide.com>,
	joerg Reisenweber <joerg@openmoko.org>,
	<linux-omap@vger.kernel.org>,
	Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>,
	Sebastian Reichel <sre@kernel.org>,
	Aaro Koskinen <aaro.koskinen@iki.fi>, Pavel Machek <pavel@ucw.cz>,
	Nishanth Menon <nm@ti.com>, Felipe Balbi <balbi@kernel.org>
Subject: Re: [PATCH] usb: musb: debugfs: allow forcing host mode together with speed in testmode
Date: Thu, 15 Dec 2016 22:03:19 -0600	[thread overview]
Message-ID: <20161216040319.GA18350@uda0271908> (raw)
In-Reply-To: <1481743425-25847-1-git-send-email-pali.rohar@gmail.com>

On Wed, Dec 14, 2016 at 08:23:45PM +0100, Pali Rohár wrote:
> Based on the musb ug, force_host bit is allowed to be set along with
> force_hs or force_fs bit.
> 
> It could help to implement forced host mode via testmode on Nokia N900.
> 
> Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
> ---
>  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))

	if (test & (MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS) ==
			MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS)

or even simpler:

	if (test == MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS)

since multiple tests at the same time are not allowed.

> +		seq_printf(s, "force host full-speed\n");
> +
> +	else if (test & (MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_HS))

	else if (test == MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_HS)

Regards,
-Bin.