All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Brownell <david-b@pacbell.net>
To: "Stanley.Miao" <stanley.miao@windriver.com>
Cc: linux-omap@vger.kernel.org
Subject: Re: [PATCH] OMAP: Switch to gpio_direction_output in OMAP_LDP.
Date: Thu, 20 Nov 2008 11:11:09 -0800	[thread overview]
Message-ID: <200811201111.09749.david-b@pacbell.net> (raw)
In-Reply-To: <1227189663-27966-1-git-send-email-stanley.miao@windriver.com>

On Thursday 20 November 2008, Stanley.Miao wrote:
> -       omap_set_gpio_direction(LCD_PANEL_QVGA_GPIO, 0);
> -       omap_set_gpio_direction(LCD_PANEL_RESET_GPIO, 0);
>         gpio_direction_output(LCD_PANEL_ENABLE_GPIO, 0);
>         gpio_direction_output(LCD_PANEL_BACKLIGHT_GPIO, 0);

Nothing does

	gpio_request(LCD_PANEL_QVGA_GPIO, "qvga something");
	gpio_request(LCD_PANEL_RESET_GPIO, "lcd reset");

And by removing the initial direction setting call (above),
behavior of at least the reset line changes:  it's no longer
pullsed low.

It'd be better to change the direction setting calls above
(setting an initial low value), and then make the calls
below use gpio_set_value().

  
>  #ifdef CONFIG_FB_OMAP_LCD_VGA
> -       omap_set_gpio_dataout(LCD_PANEL_QVGA_GPIO, 0);
> +       gpio_direction_output(LCD_PANEL_QVGA_GPIO, 0);
>  #else
> -       omap_set_gpio_dataout(LCD_PANEL_QVGA_GPIO, 1);
> +       gpio_direction_output(LCD_PANEL_QVGA_GPIO, 1);
>  #endif
> -       omap_set_gpio_dataout(LCD_PANEL_RESET_GPIO, 1);
> +       gpio_direction_output(LCD_PANEL_RESET_GPIO, 1);

Use gpio_set_value() to replace omap_set_gpio_dataout(), except
when initializing.  The reset pin *was* being toggled...

- Dave

--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

  reply	other threads:[~2008-11-20 19:11 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-20 14:01 [PATCH] OMAP: Switch to gpio_direction_output in OMAP_LDP Stanley.Miao
2008-11-20 19:11 ` David Brownell [this message]
2008-11-21  7:50   ` stanley.miao
2008-11-21  7:52     ` David Brownell
2008-11-21  8:21       ` stanley.miao

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=200811201111.09749.david-b@pacbell.net \
    --to=david-b@pacbell.net \
    --cc=linux-omap@vger.kernel.org \
    --cc=stanley.miao@windriver.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.