Hi Stephen,
On Fri, Jun 15, 2012 at 1:45 AM, Stephen Warren swarren@wwwdotorg.orgwrote:
On 06/13/2012 10:19 AM, Simon Glass wrote:
This driver supports driving a single LCD and providing a U-Boot console on it.
+int fdt_decode_lcd(const void *blob, struct fdt_lcd *config)
fdtdec_decode_gpio(blob, display_node,"nvidia,backlight-vdd-gpios",
&config->backlight_vdd);Given that's a power supply control, I expect this to be represented as a regulator in the DT, not as a simple GPIO (it could be controlled by a register bit in a PMU on some boards).
Hmm we don't have regulator support in U-Boot as yet. Any ideas? It is possible that it might come towards the end of the year as part of some other upstreaming work, but I am not sure. At lot of these sorts of things are really hard in U-Boot until we have a device model.
+void lcd_enable(void) +{
/** Backlight and power init will be done separately in* tegra_lcd_check_next_stage(), which should be called in* board_late_init().** U-Boot code supports only colour depth, selected at compiletime.
* The device tree setting should match this. Otherwise the display* will not look right, and U-Boot may crash.*/if (config.log2_bpp != LCD_BPP) {printf("%s: Error: LCD depth configured in FDT (%d =%dbpp)"
" must match setting of LCD_BPP (%d)\n", __func__,config.log2_bpp, config.bpp, LCD_BPP);}+}
I wonder why even read the configuration from DT if the value can't be used?
The conflict is in one place and has a clear warning, so if U-Boot does support this in the future, we can adjust it.
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
@@ -43,6 +43,7 @@ static const char * const compat_names[COMPAT_COUNT] =
{
COMPAT(NVIDIA_TEGRA20_DISPLAY, "nvidia,tegra20-display"),Surely all the DT plumbing for the display controller itself should be in the previous patch that adds the display controller driver.
The LCD stuff that sits on top of that seems like it should be a separate node in DT, and the two patches kept much more separate.
I have made the LCD a subnode of the display controller. Let's see what Thierry says about the kernel binding.
I will move this compatible string to the previous patch.
Regards, Simon