drivers/video/fbdev/pxa168fb.c

File Facts

System

Linux kernel

Corpus path

drivers/video/fbdev/pxa168fb.c

Extension

.c

Size

20459 bytes

Lines

810

Domain

Driver Families

Bucket

drivers/video

Inferred role

Driver Families: implementation source

Status

source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/module.h
• linux/kernel.h
• linux/sched.h
• linux/string.h
• linux/interrupt.h
• linux/slab.h
• linux/fb.h
• linux/delay.h
• linux/init.h
• linux/io.h
• linux/ioport.h
• linux/platform_device.h
• linux/dma-mapping.h
• linux/clk.h
• linux/err.h
• linux/uaccess.h
• video/pxa168fb.h
• pxa168fb.h

Detected Declarations

• function Copyright
• function set_pix_fmt
• function set_mode
• function pxa168fb_check_var
• function set_clock_divider
• function set_dma_control0
• function set_dma_control1
• function set_graphics_start
• function set_dumb_panel_control
• function set_dumb_screen_dimensions
• function pxa168fb_set_par
• function chan_to_field
• function to_rgb
• function pxa168fb_setcolreg
• function pxa168fb_blank
• function pxa168fb_pan_display
• function pxa168fb_handle_irq
• function pxa168fb_init_mode
• function pxa168fb_probe
• function pxa168fb_remove

Annotated Snippet

if (var->transp.length == 0) {
			if (var->red.offset >= var->blue.offset)
				return PIX_FMT_RGB565;
			else
				return PIX_FMT_BGR565;
		}

		if (var->transp.length == 1 && var->green.length <= 5) {
			if (var->red.offset >= var->blue.offset)
				return PIX_FMT_RGB1555;
			else
				return PIX_FMT_BGR1555;
		}
	}

	/*
	 * Check for 888/A888.
	 */
	if (var->bits_per_pixel <= 32 && var->red.length <= 8 &&
	    var->green.length <= 8 && var->blue.length <= 8) {
		if (var->bits_per_pixel == 24 && var->transp.length == 0) {
			if (var->red.offset >= var->blue.offset)
				return PIX_FMT_RGB888PACK;
			else
				return PIX_FMT_BGR888PACK;
		}

		if (var->bits_per_pixel == 32 && var->transp.length == 8) {
			if (var->red.offset >= var->blue.offset)
				return PIX_FMT_RGBA888;
			else
				return PIX_FMT_BGRA888;
		} else {
			if (var->red.offset >= var->blue.offset)
				return PIX_FMT_RGB888UNPACK;
			else
				return PIX_FMT_BGR888UNPACK;
		}
	}

	return -EINVAL;
}

static void set_pix_fmt(struct fb_var_screeninfo *var, int pix_fmt)
{
	switch (pix_fmt) {
	case PIX_FMT_RGB565:
		var->bits_per_pixel = 16;
		var->red.offset = 11;    var->red.length = 5;
		var->green.offset = 5;   var->green.length = 6;
		var->blue.offset = 0;    var->blue.length = 5;
		var->transp.offset = 0;  var->transp.length = 0;
		break;
	case PIX_FMT_BGR565:
		var->bits_per_pixel = 16;
		var->red.offset = 0;     var->red.length = 5;
		var->green.offset = 5;   var->green.length = 6;
		var->blue.offset = 11;   var->blue.length = 5;
		var->transp.offset = 0;  var->transp.length = 0;
		break;
	case PIX_FMT_RGB1555:
		var->bits_per_pixel = 16;
		var->red.offset = 10;    var->red.length = 5;
		var->green.offset = 5;   var->green.length = 5;
		var->blue.offset = 0;    var->blue.length = 5;
		var->transp.offset = 15; var->transp.length = 1;
		break;
	case PIX_FMT_BGR1555:
		var->bits_per_pixel = 16;
		var->red.offset = 0;     var->red.length = 5;
		var->green.offset = 5;   var->green.length = 5;
		var->blue.offset = 10;   var->blue.length = 5;
		var->transp.offset = 15; var->transp.length = 1;
		break;
	case PIX_FMT_RGB888PACK:
		var->bits_per_pixel = 24;
		var->red.offset = 16;    var->red.length = 8;
		var->green.offset = 8;   var->green.length = 8;
		var->blue.offset = 0;    var->blue.length = 8;
		var->transp.offset = 0;  var->transp.length = 0;
		break;
	case PIX_FMT_BGR888PACK:
		var->bits_per_pixel = 24;
		var->red.offset = 0;     var->red.length = 8;
		var->green.offset = 8;   var->green.length = 8;
		var->blue.offset = 16;   var->blue.length = 8;
		var->transp.offset = 0;  var->transp.length = 0;
		break;
	case PIX_FMT_RGBA888:
		var->bits_per_pixel = 32;

Annotation

• Immediate include surface: `linux/module.h`, `linux/kernel.h`, `linux/sched.h`, `linux/string.h`, `linux/interrupt.h`, `linux/slab.h`, `linux/fb.h`, `linux/delay.h`.
• Detected declarations: `function Copyright`, `function set_pix_fmt`, `function set_mode`, `function pxa168fb_check_var`, `function set_clock_divider`, `function set_dma_control0`, `function set_dma_control1`, `function set_graphics_start`, `function set_dumb_panel_control`, `function set_dumb_screen_dimensions`.
• Atlas domain: Driver Families / drivers/video.
• Implementation status: source implementation candidate.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.