[U-Boot] [PATCH 04/16] dm: x86: Add a uclass for an Low Pin Count (LPC) device

Simon Glass sjg at chromium.org
Tue Feb 24 14:23:59 CET 2015


On x86 systems this device is commonly used to provide legacy port access.
It is sort-of a replacement for the old ISA bus.

Add a uclass for this, and allow it to have child devices.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 arch/x86/lib/Makefile     |  1 +
 arch/x86/lib/lpc-uclass.c | 28 ++++++++++++++++++++++++++++
 include/dm/uclass-id.h    |  1 +
 3 files changed, 30 insertions(+)
 create mode 100644 arch/x86/lib/lpc-uclass.c

diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index fe022f6..6c571dd 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_HAVE_FSP) += cmd_hob.o
 obj-y	+= gcc.o
 obj-y	+= init_helpers.o
 obj-y	+= interrupts.o
+obj-y	+= lpc-uclass.o
 obj-y += cmd_mtrr.o
 obj-$(CONFIG_SYS_PCAT_INTERRUPTS) += pcat_interrupts.o
 obj-$(CONFIG_SYS_PCAT_TIMER) += pcat_timer.o
diff --git a/arch/x86/lib/lpc-uclass.c b/arch/x86/lib/lpc-uclass.c
new file mode 100644
index 0000000..6aeb4d4
--- /dev/null
+++ b/arch/x86/lib/lpc-uclass.c
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg at chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/root.h>
+
+static int lpc_uclass_post_bind(struct udevice *bus)
+{
+	/*
+	 * Scan the device tree for devices
+	 *
+	 * Before relocation, only bind devices marked for pre-relocation
+	 * use.
+	 */
+	return dm_scan_fdt_node(bus, gd->fdt_blob, bus->of_offset,
+				gd->flags & GD_FLG_RELOC ? false : true);
+}
+
+UCLASS_DRIVER(lpc) = {
+	.id		= UCLASS_LPC,
+	.name		= "lpc",
+	.post_bind	= lpc_uclass_post_bind,
+};
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 047ac15..458c322 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -38,6 +38,7 @@ enum uclass_id {
 	UCLASS_PCI,		/* PCI bus */
 	UCLASS_PCI_GENERIC,	/* Generic PCI bus device */
 	UCLASS_PCH,		/* x86 platform controller hub */
+	UCLASS_LPC,		/* x86 'low pin count' interface */
 
 	UCLASS_COUNT,
 	UCLASS_INVALID = -1,
-- 
2.2.0.rc0.207.ga3a616c



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