From owner-svn-src-all@freebsd.org Mon Jul 15 21:40:58 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D2C4FC496C; Mon, 15 Jul 2019 21:40:58 +0000 (UTC) (envelope-from ian@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id B609D80D20; Mon, 15 Jul 2019 21:40:58 +0000 (UTC) (envelope-from ian@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 929C923C36; Mon, 15 Jul 2019 21:40:58 +0000 (UTC) (envelope-from ian@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x6FLewor063650; Mon, 15 Jul 2019 21:40:58 GMT (envelope-from ian@FreeBSD.org) Received: (from ian@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x6FLewnE063649; Mon, 15 Jul 2019 21:40:58 GMT (envelope-from ian@FreeBSD.org) Message-Id: <201907152140.x6FLewnE063649@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: ian set sender to ian@FreeBSD.org using -f From: Ian Lepore Date: Mon, 15 Jul 2019 21:40:58 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r350015 - head/sys/dev/iicbus X-SVN-Group: head X-SVN-Commit-Author: ian X-SVN-Commit-Paths: head/sys/dev/iicbus X-SVN-Commit-Revision: 350015 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: B609D80D20 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.96 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.996,0]; NEURAL_HAM_SHORT(-0.96)[-0.963,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_HAM_LONG(-1.00)[-1.000,0] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 15 Jul 2019 21:40:58 -0000 Author: ian Date: Mon Jul 15 21:40:58 2019 New Revision: 350015 URL: https://svnweb.freebsd.org/changeset/base/350015 Log: Fix nxprtc(4) on systems that support i2c repeat-start correctly. An obscure footnote in the datasheets for the PCx2127, PCx2129, and PCF8523 rtc chips states that the chips do not support i2c repeat-start operations. When the driver was originally written and tested, the i2c bus on that system also didn't support repeat-start and just quietly turned repeat-start operations into a stop-then-start, making it appear that the nxprtc driver was working properly. The repeat-start situation only comes up on reads, so instead of using the standard iicdev_readfrom(), use a local nxprtc_readfrom(), which is just a cut-and-pasted copy of iicdev_readfrom(), modified to send two separate start-data-stop sequences instead of using repeat-start. Modified: head/sys/dev/iicbus/nxprtc.c Modified: head/sys/dev/iicbus/nxprtc.c ============================================================================== --- head/sys/dev/iicbus/nxprtc.c Mon Jul 15 21:26:55 2019 (r350014) +++ head/sys/dev/iicbus/nxprtc.c Mon Jul 15 21:40:58 2019 (r350015) @@ -236,10 +236,43 @@ static nxprtc_compat_data compat_data[] = { }; static int +nxprtc_readfrom(device_t slavedev, uint8_t regaddr, void *buffer, + uint16_t buflen, int waithow) +{ + struct iic_msg msg; + int err; + uint8_t slaveaddr; + + /* + * Two transfers back to back with a stop and start between them; first we + * write the address-within-device, then we read from the device. This + * is used instead of the standard iicdev_readfrom() because some of the + * chips we service don't support i2c repeat-start operations (grrrrr) + * so we do two completely separate transfers with a full stop between. + */ + slaveaddr = iicbus_get_addr(slavedev); + + msg.slave = slaveaddr; + msg.flags = IIC_M_WR; + msg.len = 1; + msg.buf = ®addr; + + if ((err = iicbus_transfer_excl(slavedev, &msg, 1, waithow)) != 0) + return (err); + + msg.slave = slaveaddr; + msg.flags = IIC_M_RD; + msg.len = buflen; + msg.buf = buffer; + + return (iicbus_transfer_excl(slavedev, &msg, 1, waithow)); +} + +static int read_reg(struct nxprtc_softc *sc, uint8_t reg, uint8_t *val) { - return (iicdev_readfrom(sc->dev, reg, val, sizeof(*val), WAITFLAGS)); + return (nxprtc_readfrom(sc->dev, reg, val, sizeof(*val), WAITFLAGS)); } static int @@ -272,7 +305,7 @@ read_timeregs(struct nxprtc_softc *sc, struct time_reg if (tmr1 != tmr2) continue; } - if ((err = iicdev_readfrom(sc->dev, sc->secaddr, tregs, + if ((err = nxprtc_readfrom(sc->dev, sc->secaddr, tregs, sizeof(*tregs), WAITFLAGS)) != 0) break; } while (sc->use_timer && tregs->sec != sec);