Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4ba66a97 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

arch: remove blackfin port

The Analog Devices Blackfin port was added in 2007 and was rather
active for a while, but all work on it has come to a standstill
over time, as Analog have changed their product line-up.

Aaron Wu confirmed that the architecture port is no longer relevant,
and multiple people suggested removing blackfin independently because
of some of its oddities like a non-working SMP port, and the amount of
duplication between the chip variants, which cause extra work when
doing cross-architecture changes.

Link: https://docs.blackfin.uclinux.org/


Acked-by: default avatarAaron Wu <Aaron.Wu@analog.com>
Acked-by: default avatarBryan Wu <cooloney@gmail.com>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mike Frysinger <vapier@chromium.org>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent b8c9c8f0
Loading
Loading
Loading
Loading
+0 −2
Original line number Diff line number Diff line
@@ -66,8 +66,6 @@ backlight/
	- directory with info on controlling backlights in flat panel displays
bcache.txt
	- Block-layer cache on fast SSDs to improve slow (raid) I/O performance.
blackfin/
	- directory with documentation for the Blackfin arch.
block/
	- info on the Block I/O (BIO) layer.
blockdev/
+0 −1
Original line number Diff line number Diff line
@@ -89,7 +89,6 @@ parameter is applicable::
	APM	Advanced Power Management support is enabled.
	ARM	ARM architecture is enabled.
	AX25	Appropriate AX.25 support is enabled.
	BLACKFIN Blackfin architecture is enabled.
	CLK	Common clock infrastructure is enabled.
	CMA	Contiguous Memory Area support is enabled.
	DRM	Direct Rendering Management support is enabled.
+1 −1
Original line number Diff line number Diff line
@@ -1025,7 +1025,7 @@
			address. The serial port must already be setup
			and configured. Options are not yet supported.

	earlyprintk=	[X86,SH,BLACKFIN,ARM,M68k,S390]
	earlyprintk=	[X86,SH,ARM,M68k,S390]
			earlyprintk=vga
			earlyprintk=efi
			earlyprintk=sclp

Documentation/blackfin/00-INDEX

deleted100644 → 0
+0 −6
Original line number Diff line number Diff line
00-INDEX
	- This file
bfin-gpio-notes.txt
	- Notes in developing/using bfin-gpio driver.
bfin-spi-notes.txt
	- Notes for using bfin spi bus driver.
+0 −71
Original line number Diff line number Diff line
/*
 * File:         Documentation/blackfin/bfin-gpio-notes.txt
 * Based on:
 * Author:
 *
 * Created:      $Id: bfin-gpio-note.txt 2008-11-24 16:42 grafyang $
 * Description:  This file contains the notes in developing/using bfin-gpio.
 *
 *
 * Rev:
 *
 * Modified:
 *               Copyright 2004-2008 Analog Devices Inc.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 */


1. Blackfin GPIO introduction

    There are many GPIO pins on Blackfin. Most of these pins are muxed to
    multi-functions. They can be configured as peripheral, or just as GPIO,
    configured to input with interrupt enabled, or output.

    For detailed information, please see "arch/blackfin/kernel/bfin_gpio.c",
    or the relevant HRM.


2. Avoiding resource conflict

    Followed function groups are used to avoiding resource conflict,
    - Use the pin as peripheral,
	int peripheral_request(unsigned short per, const char *label);
	int peripheral_request_list(const unsigned short per[], const char *label);
	void peripheral_free(unsigned short per);
	void peripheral_free_list(const unsigned short per[]);
    - Use the pin as GPIO,
	int bfin_gpio_request(unsigned gpio, const char *label);
	void bfin_gpio_free(unsigned gpio);
    - Use the pin as GPIO interrupt,
	int bfin_gpio_irq_request(unsigned gpio, const char *label);
	void bfin_gpio_irq_free(unsigned gpio);

    The request functions will record the function state for a certain pin,
    the free functions will clear its function state.
    Once a pin is requested, it can't be requested again before it is freed by
    previous caller, otherwise kernel will dump stacks, and the request
    function fail.
    These functions are wrapped by other functions, most of the users need not
    care.


3. But there are some exceptions
    - Kernel permit the identical GPIO be requested both as GPIO and GPIO
    interrupt.
    Some drivers, like gpio-keys, need this behavior. Kernel only print out
    warning messages like,
	bfin-gpio: GPIO 24 is already reserved by gpio-keys: BTN0, and you are
configuring it as IRQ!

        Note: Consider the case that, if there are two drivers need the
	identical GPIO, one of them use it as GPIO, the other use it as
	GPIO interrupt. This will really cause resource conflict. So if
	there is any abnormal driver behavior, please check the bfin-gpio
	warning messages.

    - Kernel permit the identical GPIO be requested from the same driver twice.


Loading