From patchwork Mon Feb 27 13:34:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 13153486 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9EE11C64ED6 for ; Mon, 27 Feb 2023 13:35:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229658AbjB0Nfa (ORCPT ); Mon, 27 Feb 2023 08:35:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49804 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229558AbjB0Nf3 (ORCPT ); Mon, 27 Feb 2023 08:35:29 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AEC392; Mon, 27 Feb 2023 05:35:23 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C651B60C8C; Mon, 27 Feb 2023 13:35:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6A26C433EF; Mon, 27 Feb 2023 13:35:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677504922; bh=d2Lq3RBqNZi5D42D4fx6Gg5riTJj4LbmcuLWDvTa4rU=; h=From:To:Cc:Subject:Date:From; b=HlILoM4N/Quib/DDjMXNKGh0uKYNnukoM4TWIyiEcCNPDxsI+x7eMxEMC+aWZBhBy BIGIxnJF9+flEIjkU0+uhHhjJD5E7cTtmrJiCrpLUUNz7YgPt4miqaKIFyjJHql6P+ aCtb4/R4QDL1ILQAu3FS9/0xTrNeWn7aHjNG6qFZZgTeOejqNNrcS06xZc4uXQselv F/5YoCmEZNEkCGTt4kSQgBKyWaWyVTEMja9q6p13az4cP48+f1jj6ldPAlLCwV25ML yfd65nxGtqy2PXCzz5CJ4cbNKp+CEgCMxHyEDFtl+12r25MJLJ/RWuyJNBvjzQRJxW WS95XWFRg86sw== From: Arnd Bergmann To: Dominik Brodowski , linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Bjorn Helgaas , Florian Fainelli , H Hartley Sweeten , Ian Abbott , Jakub Kicinski , Kevin Cernekee , Lukas Wunner , Manuel Lauss , Oliver Hartkopp , Olof Johansson , Robert Jarzmik , YOKOTA Hiroshi , bcm-kernel-feedback-list@broadcom.com, linux-arm-kernel@lists.infradead.org, linux-can@vger.kernel.org, linux-mips@vger.kernel.org, linux-pci@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: [RFC 0/6] pcmcia: separate 16-bit support from cardbus Date: Mon, 27 Feb 2023 14:34:51 +0100 Message-Id: <20230227133457.431729-1-arnd@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-State: RFC From: Arnd Bergmann Based on some recent discussions [1][2][3], I experimented wtih what drivers/pcmcia would look like if we completely removed 16-bit support, which was one of the options that Dominik suggested for winding down pcmcia maintenance. The remaining cardbus/yenta support is essentially a PCI hotplug driver with a slightly unusual sysfs interface, and it would still support all 32-bit cardbus hosts and cards, but no longer work with the even older 16-bit cards that require the pcmcia_driver infrastructure. I don't expect this to be a problem normal laptop support, as the last PC models that predate Cardbus support (e.g. 1997 ThinkPad 380ED) are all limited to i586MMX CPUs and 80MB of RAM. This is barely enough to boot Tiny Core Linux but not a regular distro. Support for device drivers is somewhat less clear. Losing support for 16-bit cards in cardbus sockets is obviously a limiting factor for anyone who still has those cards, but there is also a good chance that the only reason to keep the cards around is for using them in pre-cardbus machines that cannot be upgrade to 32-bit devices. Completely removing the 16-bit PCMCIA support would however break some 20+ year old embedded machines that rely on CompactFlash cards as their mass-storage device (extension), this notably includes early PocketPC models and the reference implementations for OMAP1, StrongARM1100, Alchemy and PA-Semi. All of these are still maintained, though most of the PocketPC machines got removed in the 6.3 merge window and the PA-Semi Electra board is the only one that was introduced after 2003. The approach that I take in this series is to split drivers/pcmcia into two mutually incompatible parts: the Cardbus support contains all the code that is relevant for post-1997 laptops and gets moved to drivers/pci/hotplug, while the drivers/pcmcia/ subsystem is retained for both the older laptops and the embedded systems but no longer works with the yenta socket host driver. The BCM63xx PCMCIA/Cardbus host driver appears to be unused and conflicts with this series, so it is removed in the process. My series does not touch any of the pcmcia_driver instances, but if there is consensus about splitting out the cardbus support, a lot of them can probably get removed as a follow-up. [1] https://lore.kernel.org/all/Y07d7rMvd5++85BJ@owl.dominikbrodowski.net/ [2] https://lore.kernel.org/all/c5b39544-a4fb-4796-a046-0b9be9853787@app.fastmail.com/ [3] https://lore.kernel.org/all/20230222092302.6348-1-jirislaby@kernel.org/ Cc: Bjorn Helgaas Cc: Dominik Brodowski Cc: Florian Fainelli Cc: H Hartley Sweeten Cc: Ian Abbott Cc: Jakub Kicinski Cc: Kevin Cernekee Cc: Lukas Wunner Cc: Manuel Lauss Cc: Oliver Hartkopp Cc: Olof Johansson Cc: Robert Jarzmik Cc: YOKOTA Hiroshi Cc: bcm-kernel-feedback-list@broadcom.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-can@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Arnd Bergmann (6): pccard: remove bcm63xx socket driver pccard: split cardbus support from pcmcia yenta_socket: copy pccard core code into driver yenta_socket: remove dead code pccard: drop remnants of cardbus support pci: hotplug: move cardbus code from drivers/pcmcia arch/mips/bcm63xx/Makefile | 2 +- arch/mips/bcm63xx/boards/board_bcm963xx.c | 14 - arch/mips/bcm63xx/dev-pcmcia.c | 144 - arch/mips/configs/bcm63xx_defconfig | 1 - .../asm/mach-bcm63xx/bcm63xx_dev_pcmcia.h | 14 - arch/mips/pci/ops-bcm63xx.c | 294 -- arch/mips/pci/pci-bcm63xx.c | 44 - drivers/Makefile | 2 +- drivers/pci/hotplug/Kconfig | 56 + drivers/pci/hotplug/Makefile | 1 + drivers/pci/hotplug/yenta_socket.c | 4056 +++++++++++++++++ drivers/pcmcia/Kconfig | 63 +- drivers/pcmcia/Makefile | 13 +- drivers/pcmcia/bcm63xx_pcmcia.c | 538 --- drivers/pcmcia/bcm63xx_pcmcia.h | 61 - drivers/pcmcia/cardbus.c | 124 - drivers/pcmcia/cistpl.c | 10 +- drivers/pcmcia/cs.c | 103 +- drivers/pcmcia/cs_internal.h | 10 +- drivers/pcmcia/ds.c | 14 +- drivers/pcmcia/i82092.c | 2 +- drivers/pcmcia/i82365.c | 2 +- drivers/pcmcia/o2micro.h | 183 - drivers/pcmcia/pd6729.c | 3 +- drivers/pcmcia/ricoh.h | 169 - drivers/pcmcia/socket_sysfs.c | 2 - drivers/pcmcia/ti113x.h | 978 ---- drivers/pcmcia/topic.h | 168 - drivers/pcmcia/yenta_socket.c | 1455 ------ drivers/pcmcia/yenta_socket.h | 136 - {drivers => include}/pcmcia/i82365.h | 0 include/pcmcia/ss.h | 21 - 32 files changed, 4147 insertions(+), 4536 deletions(-) delete mode 100644 arch/mips/bcm63xx/dev-pcmcia.c delete mode 100644 arch/mips/include/asm/mach-bcm63xx/bcm63xx_dev_pcmcia.h create mode 100644 drivers/pci/hotplug/yenta_socket.c delete mode 100644 drivers/pcmcia/bcm63xx_pcmcia.c delete mode 100644 drivers/pcmcia/bcm63xx_pcmcia.h delete mode 100644 drivers/pcmcia/cardbus.c delete mode 100644 drivers/pcmcia/o2micro.h delete mode 100644 drivers/pcmcia/ti113x.h delete mode 100644 drivers/pcmcia/topic.h delete mode 100644 drivers/pcmcia/yenta_socket.c delete mode 100644 drivers/pcmcia/yenta_socket.h rename {drivers => include}/pcmcia/i82365.h (100%)