From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Dunn Date: Tue, 09 Apr 2013 10:02:44 -0700 Subject: [U-Boot] [PATCH 3/8] pxa_lcd: allow L_BIAS line to be unused In-Reply-To: <201304080728.06230.marex@denx.de> References: <1365352865-2137-1-git-send-email-mikedunn@newsguy.com> <1365352865-2137-4-git-send-email-mikedunn@newsguy.com> <201304080728.06230.marex@denx.de> Message-ID: <516449B4.3010706@newsguy.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 04/07/2013 10:28 PM, Marek Vasut wrote: > Dear Mike Dunn, > >> This patch adds a config option CONFIG_SYS_LCD_PXA_NO_L_BIAS, which causes >> the lcd controller initialization code to leave as an ordinary gpio the >> line that is typically configured as the lcd L_BIAS alternate function >> (this is the gpio 77 line). >> >> For some reason (I don't have a datasheet), the lcd device on the >> palmtreo680 board does not use the L_BIAS line. PalmOS does not configure >> the gpio 77 line for the L_BIAS alternate function, and if it is >> configured as such, the lcd does not work. >> >> Signed-off-by: Mike Dunn > > The other option would be to pull the GPIO setup from the driver. That'd be the > best. Well, there's a lot of shared code in pxafb_setup_gpio() that handles pin configuration for all possible interface widths. But after looking at this problem some more, I realized that the board-specific lcd_enable() is called after the pxa driver's initialization, so the board code can undo the L_BIAS pin configuration. Not elegant, but better than the ugly #ifdefs. Thanks, Mike