| Message ID | 1365352865-2137-4-git-send-email-mikedunn@newsguy.com |
|---|---|
| State | Superseded |
| Delegated to: | Albert ARIBAUD |
| Headers | show |
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 <mikedunn@newsguy.com> The other option would be to pull the GPIO setup from the driver. That'd be the best. Best regards, Marek Vasut
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 <mikedunn@newsguy.com> > > 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
diff --git a/drivers/video/pxa_lcd.c b/drivers/video/pxa_lcd.c index fd848ef..29f62e9 100644 --- a/drivers/video/pxa_lcd.c +++ b/drivers/video/pxa_lcd.c @@ -478,8 +478,13 @@ static void pxafb_setup_gpio (vidinfo_t *vid) /* bits 74-77 */ writel(readl(GPDR2) | (0xf << 10), GPDR2); +#ifdef CONFIG_SYS_LCD_PXA_NO_L_BIAS + writel((readl(GAFR2_L) & ~(0xff << 20)) | (0x2a << 20), + GAFR2_L); +#else writel((readl(GAFR2_L) & ~(0xff << 20)) | (0xaa << 20), - GAFR2_L); + GAFR2_L); +#endif } /* 8 bit interface */ @@ -497,8 +502,13 @@ static void pxafb_setup_gpio (vidinfo_t *vid) /* bits 74-77 */ writel(readl(GPDR2) | (0xf << 10), GPDR2); +#ifdef CONFIG_SYS_LCD_PXA_NO_L_BIAS + writel((readl(GAFR2_L) & ~(0xff << 20)) | (0x2a << 20), + GAFR2_L); +#else writel((readl(GAFR2_L) & ~(0xff << 20)) | (0xaa << 20), - GAFR2_L); + GAFR2_L); +#endif } /* 16 bit interface */ @@ -511,7 +521,11 @@ static void pxafb_setup_gpio (vidinfo_t *vid) writel((readl(GAFR1_U) & ~(0xfff << 20)) | (0xaaa << 20), GAFR1_U); +#ifdef CONFIG_SYS_LCD_PXA_NO_L_BIAS + writel((readl(GAFR2_L) & 0xf0000000) | 0x02aaaaaa, GAFR2_L); +#else writel((readl(GAFR2_L) & 0xf0000000) | 0x0aaaaaaa, GAFR2_L); +#endif } else {
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 <mikedunn@newsguy.com> --- This is a little ugly, I know, but I didn't want to try and get too fancy. drivers/video/pxa_lcd.c | 18 ++++++++++++++++-- 1 files changed, 16 insertions(+), 2 deletions(-)