From patchwork Mon Feb 21 18:29:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ivan Bornyakov X-Patchwork-Id: 12754061 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BC51AC433EF for ; Mon, 21 Feb 2022 18:49:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=tiC7blixC2axlj90jmFZE0Jes7zLMuvm5eQkoFdnWTQ=; b=W4tRirD2lu+HP2 8UsEM/SiEu544iSMn9b6qoHpPmlVuvACrCzlwZgn4FTbuS1LJ9qja+kUtkpQ3ii86ZUq3mZwE+dOl JfjcoY6OzqJwb7L135JiWf8e/M0Aowd2lxc17ll20jX41/iMNwmsxtlN01whGJ0amn+RsiAn0dI9H G8ppFPMZ4xrBrP19Ws3U89ZOnjSLGKntyb8OdYI52NWwlbeJ+bw1rgE5e2dtl31sLknujAG0eZHBS thfzltSgjq830eRW1UjhWl75hrTgJ4w7YTKZP7GcZfofnNlURlSRJ20x45FX2a4SC+RorF9PbJGJH w9RrjTimhyiOvwe4ZWqg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nMDj8-0070X0-Fl; Mon, 21 Feb 2022 18:48:02 +0000 Received: from mail.pr-group.ru ([178.18.215.3]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nMDj3-0070Vj-IW for linux-arm-kernel@lists.infradead.org; Mon, 21 Feb 2022 18:48:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=metrotek.ru; s=mail; h=from:subject:date:message-id:to:cc:mime-version:content-transfer-encoding: in-reply-to:references; bh=iP12DTx6AXw4yww953fOc8RpJjseyIeqwVhZseaFe2o=; b=FicbT577nC2sAioOHEkzSqxaiBlhYA0VcEfXqpKRu54qTxy8LZkk2d3RSOF3L8elndxg+dwPFVZs4 IWPpd7UuBtUbpF288WFqrvz3Ww1LSicd0Z4aHj1Si8m8bkf+ABu9+X7SBa3nHyLlHFLD0/ZjxujmIr lxttUEFhndc3dBdibgPq2tlZt1UnlfdUQ1Lkecj6ZiIP/djSQGwAtR+5+M9dssqi02TFC1CVK3vjjy 3n7T8Ng94vAfZvTS8fWoylO2WKKwa5a/HnpvgwG/ggVzkH7TiGwL8MA6CtGl86tG4MIoIanC9cmR38 Nl8bC2dwLdaV+Xp9nZVz/ZVFHge/b/A== X-Kerio-Anti-Spam: Build: [Engines: 2.16.2.1403, Stamp: 3], Multi: [Enabled, t: (0.000019,0.024044)], BW: [Enabled, t: (0.000035,0.000002)], RTDA: [Enabled, t: (0.065211), Hit: No, Details: v2.25.0; Id: 15.52k95i.1fsepovmq.23j6; mclb], total: 0(700) X-Footer: bWV0cm90ZWsucnU= Received: from localhost.localdomain ([178.70.66.234]) (authenticated user i.bornyakov@metrotek.ru) by mail.pr-group.ru with ESMTPSA (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256 bits)); Mon, 21 Feb 2022 21:47:49 +0300 From: Ivan Bornyakov To: Cc: shawnguo@kernel.org, s.hauer@pengutronix.de, festevam@gmail.com, kernel@pengutronix.de, linux-imx@nxp.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, system@metrotek.ru, Ivan Bornyakov Subject: [PATCH v2] bus: imx-weim: add DT overlay support for WEIM bus Date: Mon, 21 Feb 2022 21:29:10 +0300 Message-Id: <20220221182910.18095-1-i.bornyakov@metrotek.ru> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220205055006.23447-1-i.bornyakov@metrotek.ru> References: <20220205055006.23447-1-i.bornyakov@metrotek.ru> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220221_104758_157479_361286E5 X-CRM114-Status: GOOD ( 24.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add OF reconfiguration notifier handler for WEIM bus to setup Chip Select timings on runtime creation of child devices. However, it is not possible to load another DT overlay with conflicting CS timings with previously loaded overlay, even if the first one is unloaded. The reason is that there is no acces to CS timing property of a device node being removed, thus we can't track which of configured CS are available for re-configuration. Signed-off-by: Ivan Bornyakov --- Changelog: v1 -> v2: minor style fixes * rename "priv" -> weim_priv" * remove excessive newline drivers/bus/imx-weim.c | 135 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 126 insertions(+), 9 deletions(-) diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c index bccb275b65ba..80656d413750 100644 --- a/drivers/bus/imx-weim.c +++ b/drivers/bus/imx-weim.c @@ -64,6 +64,11 @@ struct cs_timing_state { struct cs_timing cs[MAX_CS_COUNT]; }; +struct weim_data { + void __iomem *base; + struct cs_timing_state timing_state; +}; + static const struct of_device_id weim_id_table[] = { /* i.MX1/21 */ { .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, }, @@ -128,21 +133,26 @@ static int imx_weim_gpr_setup(struct platform_device *pdev) } /* Parse and set the timing for this device. */ -static int weim_timing_setup(struct device *dev, - struct device_node *np, void __iomem *base, - const struct imx_weim_devtype *devtype, - struct cs_timing_state *ts) +static int weim_timing_setup(struct device *dev, struct device_node *np, + const struct imx_weim_devtype *devtype) { u32 cs_idx, value[MAX_CS_REGS_COUNT]; int i, ret; int reg_idx, num_regs; struct cs_timing *cst; + struct weim_data *weim_priv; + struct cs_timing_state *ts; + void __iomem *base; if (WARN_ON(devtype->cs_regs_count > MAX_CS_REGS_COUNT)) return -EINVAL; if (WARN_ON(devtype->cs_count > MAX_CS_COUNT)) return -EINVAL; + weim_priv = dev_get_drvdata(dev); + base = weim_priv->base; + ts = &weim_priv->timing_state; + ret = of_property_read_u32_array(np, "fsl,weim-cs-timing", value, devtype->cs_regs_count); if (ret) @@ -189,14 +199,15 @@ static int weim_timing_setup(struct device *dev, return 0; } -static int weim_parse_dt(struct platform_device *pdev, void __iomem *base) +static int weim_parse_dt(struct platform_device *pdev) { const struct of_device_id *of_id = of_match_device(weim_id_table, &pdev->dev); const struct imx_weim_devtype *devtype = of_id->data; struct device_node *child; int ret, have_child = 0; - struct cs_timing_state ts = {}; + struct weim_data *weim_priv; + void __iomem *base; u32 reg; if (devtype == &imx50_weim_devtype) { @@ -205,6 +216,9 @@ static int weim_parse_dt(struct platform_device *pdev, void __iomem *base) return ret; } + weim_priv = dev_get_drvdata(&pdev->dev); + base = weim_priv->base; + if (of_property_read_bool(pdev->dev.of_node, "fsl,burst-clk-enable")) { if (devtype->wcr_bcm) { reg = readl(base + devtype->wcr_offset); @@ -229,7 +243,7 @@ static int weim_parse_dt(struct platform_device *pdev, void __iomem *base) } for_each_available_child_of_node(pdev->dev.of_node, child) { - ret = weim_timing_setup(&pdev->dev, child, base, devtype, &ts); + ret = weim_timing_setup(&pdev->dev, child, devtype); if (ret) dev_warn(&pdev->dev, "%pOF set timing failed.\n", child); @@ -248,17 +262,25 @@ static int weim_parse_dt(struct platform_device *pdev, void __iomem *base) static int weim_probe(struct platform_device *pdev) { + struct weim_data *weim_priv; struct resource *res; struct clk *clk; void __iomem *base; int ret; + weim_priv = devm_kzalloc(&pdev->dev, sizeof(*weim_priv), GFP_KERNEL); + if (!weim_priv) + return -ENOMEM; + /* get the resource */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(base)) return PTR_ERR(base); + weim_priv->base = base; + dev_set_drvdata(&pdev->dev, weim_priv); + /* get the clock */ clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(clk)) @@ -269,7 +291,7 @@ static int weim_probe(struct platform_device *pdev) return ret; /* parse the device node */ - ret = weim_parse_dt(pdev, base); + ret = weim_parse_dt(pdev); if (ret) clk_disable_unprepare(clk); else @@ -278,6 +300,81 @@ static int weim_probe(struct platform_device *pdev) return ret; } +#if IS_ENABLED(CONFIG_OF_DYNAMIC) +static int of_weim_notify(struct notifier_block *nb, unsigned long action, + void *arg) +{ + const struct imx_weim_devtype *devtype; + struct of_reconfig_data *rd = arg; + const struct of_device_id *of_id; + struct platform_device *pdev; + int ret = NOTIFY_OK; + + switch (of_reconfig_get_state_change(action, rd)) { + case OF_RECONFIG_CHANGE_ADD: + of_id = of_match_node(weim_id_table, rd->dn->parent); + if (!of_id) + return NOTIFY_OK; /* not for us */ + + devtype = of_id->data; + + pdev = of_find_device_by_node(rd->dn->parent); + if (!pdev) { + pr_err("%s: could not find platform device for '%pOF'\n", + __func__, rd->dn->parent); + + return notifier_from_errno(-EINVAL); + } + + if (weim_timing_setup(&pdev->dev, rd->dn, devtype)) + dev_warn(&pdev->dev, + "Failed to setup timing for '%pOF'\n", rd->dn); + + if (!of_node_check_flag(rd->dn, OF_POPULATED)) { + if (!of_platform_device_create(rd->dn, NULL, &pdev->dev)) { + dev_err(&pdev->dev, + "Failed to create child device '%pOF'\n", + rd->dn); + ret = notifier_from_errno(-EINVAL); + } + } + + platform_device_put(pdev); + + break; + case OF_RECONFIG_CHANGE_REMOVE: + if (!of_node_check_flag(rd->dn, OF_POPULATED)) + return NOTIFY_OK; /* device already destroyed */ + + of_id = of_match_node(weim_id_table, rd->dn->parent); + if (!of_id) + return NOTIFY_OK; /* not for us */ + + pdev = of_find_device_by_node(rd->dn); + if (!pdev) { + dev_err(&pdev->dev, + "Could not find platform device for '%pOF'\n", + rd->dn); + + ret = notifier_from_errno(-EINVAL); + } else { + of_platform_device_destroy(&pdev->dev, NULL); + platform_device_put(pdev); + } + + break; + default: + break; + } + + return ret; +} + +struct notifier_block weim_of_notifier = { + .notifier_call = of_weim_notify, +}; +#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ + static struct platform_driver weim_driver = { .driver = { .name = "imx-weim", @@ -285,7 +382,27 @@ static struct platform_driver weim_driver = { }, .probe = weim_probe, }; -module_platform_driver(weim_driver); + +static int __init weim_init(void) +{ +#if IS_ENABLED(CONFIG_OF_DYNAMIC) + WARN_ON(of_reconfig_notifier_register(&weim_of_notifier)); +#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ + + return platform_driver_register(&weim_driver); +} +module_init(weim_init); + +static void __exit weim_exit(void) +{ +#if IS_ENABLED(CONFIG_OF_DYNAMIC) + of_reconfig_notifier_unregister(&weim_of_notifier); +#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ + + return platform_driver_unregister(&weim_driver); + +} +module_exit(weim_exit); MODULE_AUTHOR("Freescale Semiconductor Inc."); MODULE_DESCRIPTION("i.MX EIM Controller Driver");