From mboxrd@z Thu Jan 1 00:00:00 1970 From: tomi.valkeinen@ti.com (Tomi Valkeinen) Date: Wed, 14 Dec 2011 10:39:07 +0200 Subject: [PATCH v2] ARM: OMAP3LOGIC: Adding DSS support In-Reply-To: <1323762769-25045-1-git-send-email-alexg@meprolight.com> References: <1323762769-25045-1-git-send-email-alexg@meprolight.com> Message-ID: <1323851947.1873.95.camel@deskari> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, 2011-12-13 at 09:52 +0200, Alex wrote: > This patch adds DSS2 support to the LogicPD OMAP 35x Torpedo boardfile. LCD and > TV-out are supported. > > Signed-off-by: Alex Gershgorin Overall looks fine. A few questions below about the GPIOs, though. > +static void __init omap3logic_display_init(void) > +{ > + int r; > + > + r = gpio_request_array(omap3logic_dss_gpios, > + ARRAY_SIZE(omap3logic_dss_gpios)); > + if (r) { > + printk(KERN_ERR "failed to get lcd_panel_* gpios\n"); > + return; > + } > + > + gpio_export(OMAP3_TORPEDO_LCD_BACKLIGHT_GPIO, 0); > + gpio_export(OMAP3_TORPEDO_LCD_ENABLE_GPIO, 0); > + gpio_export(OMAP3_TORPEDO_LCD_PWM_GPIO, 0); Why do you want to export these GPIOs? They are handled here in the board file, and I don't think there's any reason the userspace would need to touch them. > + gpio_set_value(OMAP3_TORPEDO_LCD_BACKLIGHT_GPIO, 0); > + gpio_set_value(OMAP3_TORPEDO_LCD_ENABLE_GPIO, 0); > + gpio_set_value(OMAP3_TORPEDO_LCD_PWM_GPIO, 0); These are already set to 0 in gpio_request_array, as you've defined the flag "GPIOF_OUT_INIT_LOW". > + > + msleep(50); > + gpio_set_value(OMAP3_TORPEDO_LCD_PWM_GPIO, 1); What does this do, and why do you need msleep(50)? I understand LCD_ENABLE gpio enables the LCD panel, but what exactly do LCD_BACKLIGHT and LCD_PWM gpios do? Why don't you set/unset LCD_PWM in the panel enable/disable functions like the other gpios? Tomi -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 836 bytes Desc: This is a digitally signed message part URL: