From patchwork Mon Jun 6 10:03:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Ilpo_J=C3=A4rvinen?= X-Patchwork-Id: 579245 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 2149DC43334 for ; Mon, 6 Jun 2022 10:05:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233280AbiFFKFd (ORCPT ); Mon, 6 Jun 2022 06:05:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233036AbiFFKF3 (ORCPT ); Mon, 6 Jun 2022 06:05:29 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A3E2F66207; Mon, 6 Jun 2022 03:05:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1654509924; x=1686045924; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=nl/Cl7bz5pNe4naULcGm3w7oTRumNgiPNhJiqVmMNic=; b=G/HkFiUOP21asFpjjl2LoKxG4Jk28WhOxGpUY8oGwfe2l/LrTStkh+dU 6YnHKiLAEZAeIgXAegB3E0ceyI78JDs/bgirCrOsJAJ5yGAuiDxmnn5V+ W4b9UMe4yNjqyzsN8wCVl0M9UWgLlIplNvsJfHT4L3+9s8ScVmeimVDEd j6ZIUM9TFq/cxLEFA55TgNtecpcGYRfBRNa6Hf07Qi4aPPSeXhmg0sjon TS3KTEE183OzoTZ4yJH34qoJq11tb3aYZYDkwKJ/y/er0x4F7HROmWTrO Job3m94YqCC2+6E4LMtOgt380CsIRI9QOmKQ0jSbWFpncd27B79R1hmXk g==; X-IronPort-AV: E=McAfee;i="6400,9594,10369"; a="362987024" X-IronPort-AV: E=Sophos;i="5.91,280,1647327600"; d="scan'208";a="362987024" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jun 2022 03:04:50 -0700 X-IronPort-AV: E=Sophos;i="5.91,280,1647327600"; d="scan'208";a="635523353" Received: from amkossek-mobl1.ger.corp.intel.com (HELO ijarvine-MOBL2.ger.corp.intel.com) ([10.252.57.11]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jun 2022 03:04:43 -0700 From: =?utf-8?q?Ilpo_J=C3=A4rvinen?= To: linux-serial@vger.kernel.org, Greg KH , Jiri Slaby Cc: =?utf-8?q?Ilpo_J=C3=A4rvinen?= , alexandre.belloni@bootlin.com, alexandre.torgue@foss.st.com, andriy.shevchenko@linux.intel.com, bcm-kernel-feedback-list@broadcom.com, claudiu.beznea@microchip.com, corbet@lwn.net, festevam@gmail.com, f.fainelli@gmail.com, kernel@pengutronix.de, linux-arm-kernel@lists.infradead.org, linux@armlinux.org.uk, linux-doc@vger.kernel.org, linux-imx@nxp.com, linux-kernel@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, mcoquelin.stm32@gmail.com, nicolas.ferre@microchip.com, nsaenz@kernel.org, richard.genoud@gmail.com, rjui@broadcom.com, sbranden@broadcom.com, s.hauer@pengutronix.de, shawnguo@kernel.org, vz@mleia.com Subject: [PATCH 00/36] RS485 serial_rs485 sanitization Date: Mon, 6 Jun 2022 13:03:57 +0300 Message-Id: <20220606100433.13793-1-ilpo.jarvinen@linux.intel.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org This series adds sanitization to serial_rs485 struct before passing it to driver's rs485_config. This takes the work Lino Sanfilippo started (0ed12afa5655^..60efd0513916) a bit further. By moving sanitization of the rs485 struct into the serial core, per driver rs485_config() is more into the point, that is, setting up the hw to realize RS485. The other benefit is that with the sanitization, the other drivers no longer need to care when new things are added to serial_rs485 as serial core handles them on the other drivers' behalf. The addressing mode changes I'll submit separately will take advantage of this. The addressing mode changes were the main motivator for doing the changes, however, I believe these changes stand on their feet even w/o considering the addressing mode changes. The series is long because per driver changes are split into two different stages. The key objectives here for the split have been to keep things bisect safe and to do changes per driver rather than in one large block. This required 4 stages: 1) Add datastructure entries & other preps (01-03) 2) Per driver rs485_supported (04-21) 3) Sanitization, core taking advantage of rs485_supported (22-24) 4) Cleanup per driver custom sanitization code (25-36) As you can see, the downside of this split is that the per driver code is split to 2+4 patches which makes some things moving less obvious. Merging them is only possible if the stages 2-4 are done in one large change (little bits here and there could be left out from it but not much). In stage 3 patches, there are a few userspace interface impacting changes with userspace api regression potential: a) Some drivers have not cleared flags/fields in per driver code while other drivers have. The old behavior is inconsistent. Now the bits will get cleaned up by serial core. I don't believe it's going to cause issues. b) Init path now sanitizes configuration if rs485_config is being called from the init path (mainly coming from dt). It attempts to repair some incorrect configurations which seems ok. However, if RS485 mode is not enabled at boot, serial_rs485 struct gets cleared in order for it to match what the port is configured with (RS232). Such clearing implies losing values that were configured through dt and that could perhaps be seen as unwanted side-effect from having consistent serial_rs485? There is also impact for the ioctl path from this clearing of serial_rs485 when RS485 is disabled but impact seems minor at most. c) Returning -EINVAL for non-legacy flags. This also affects setting bits that were previously padding (that is, all flags bits currently not defined in include/uapi/linux/serial.h). It was possible to put garbage into them earlier but no more. I guess this is not very likely a big issue. No non-legacy flags are added in this series (the addressing mode changes submitted separately will add new flags). Cc: alexandre.belloni@bootlin.com Cc: alexandre.torgue@foss.st.com Cc: andriy.shevchenko@linux.intel.com Cc: bcm-kernel-feedback-list@broadcom.com Cc: claudiu.beznea@microchip.com Cc: corbet@lwn.net Cc: festevam@gmail.com Cc: f.fainelli@gmail.com Cc: kernel@pengutronix.de Cc: linux-arm-kernel@lists.infradead.org Cc: linux@armlinux.org.uk Cc: linux-doc@vger.kernel.org Cc: linux-imx@nxp.com Cc: linux-kernel@vger.kernel.org Cc: linux-rpi-kernel@lists.infradead.org Cc: linux-stm32@st-md-mailman.stormreply.com Cc: mcoquelin.stm32@gmail.com Cc: nicolas.ferre@microchip.com Cc: nsaenz@kernel.org Cc: richard.genoud@gmail.com Cc: rjui@broadcom.com Cc: sbranden@broadcom.com Cc: s.hauer@pengutronix.de Cc: shawnguo@kernel.org Cc: vz@mleia.com Ilpo Järvinen (36): serial: Add uart_rs485_config() serial: Move serial_rs485 sanitization into separate function serial: Add rs485_supported to uart_port serial: 8250: Create serial8250_em485_supported for em485 users serial: 8250_bcm2835aux: Use serial8250_em485_supported serial: 8250_dwlib: Fill in rs485_supported serial: 8250_exar: Fill in rs485_supported serial: 8250_fintek: Fill in rs485_supported serial: 8250_lpc18cc: Fill in rs485_supported serial: 8250_of: Use serial8250_em485_supported serial: 8250_pci: Fill in rs485_supported for pci_fintek serial: pl011: Fill in rs485_supported serial: ar933x: Fill in rs485_supported serial: atmel: Fill in rs485_supported serial: fsl_lpuart: Fill in rs485_supported serial: imx: Fill in rs485_supported serial: max310x: Fill in rs485_supported serial: mcf: Fill in rs485_supported serial: omap: Fill in rs485_supported serial: sc16is7xx: Fill in rs485_supported serial: stm32: Fill in rs485_supported serial: Sanitize rs485_struct serial: Clear rs485 struct when non-RS485 mode is set serial: return -EINVAL for non-legacy RS485 flags serial: 8250_dwlib: Remove serial_rs485 sanitization serial: 8250_fintek: Remove serial_rs485 sanitization serial: 8250: lpc18xx: Remove serial_rs485 sanitization serial: 8250_pci: Remove serial_rs485 sanitization serial: pl011: Remove serial_rs485 sanitization serial: fsl_lpuart: Call core's sanitization and remove custom one serial: imx: Remove serial_rs485 sanitization serial: max310x: Remove serial_rs485 sanitization serial: 8250_exar: Remove serial_rs485 assignment serial: mcf: Remove serial_rs485 assignment serial: sc16is7xx: Remove serial_rs485 assignment serial: 8250: Remove serial_rs485 sanitization from em485 .../driver-api/serial/serial-rs485.rst | 12 +- drivers/tty/serial/8250/8250.h | 1 + drivers/tty/serial/8250/8250_bcm2835aux.c | 1 + drivers/tty/serial/8250/8250_core.c | 1 + drivers/tty/serial/8250/8250_dwlib.c | 17 +-- drivers/tty/serial/8250/8250_exar.c | 14 +- drivers/tty/serial/8250/8250_fintek.c | 29 +++-- drivers/tty/serial/8250/8250_lpc18xx.c | 20 +-- drivers/tty/serial/8250/8250_of.c | 1 + drivers/tty/serial/8250/8250_pci.c | 24 +--- drivers/tty/serial/8250/8250_port.c | 28 ++-- drivers/tty/serial/amba-pl011.c | 13 +- drivers/tty/serial/ar933x_uart.c | 7 + drivers/tty/serial/atmel_serial.c | 7 + drivers/tty/serial/fsl_lpuart.c | 25 +--- drivers/tty/serial/imx.c | 19 ++- drivers/tty/serial/max310x.c | 9 +- drivers/tty/serial/mcf.c | 7 +- drivers/tty/serial/omap-serial.c | 8 ++ drivers/tty/serial/sc16is7xx.c | 8 +- drivers/tty/serial/serial_core.c | 120 ++++++++++++++---- drivers/tty/serial/stm32-usart.c | 8 ++ include/linux/serial_core.h | 2 + 23 files changed, 247 insertions(+), 134 deletions(-)