From patchwork Fri Oct 23 03:50:39 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 7469581 Return-Path: X-Original-To: patchwork-linux-fbdev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 911909F750 for ; Fri, 23 Oct 2015 03:51:46 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 996DB208B3 for ; Fri, 23 Oct 2015 03:51:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8ABCC208BE for ; Fri, 23 Oct 2015 03:51:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752792AbbJWDvD (ORCPT ); Thu, 22 Oct 2015 23:51:03 -0400 Received: from smtp.csie.ntu.edu.tw ([140.112.30.61]:50937 "EHLO smtp.csie.ntu.edu.tw" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752276AbbJWDu7 (ORCPT ); Thu, 22 Oct 2015 23:50:59 -0400 Received: from mirror2.csie.ntu.edu.tw (mirror2.csie.ntu.edu.tw [140.112.30.76]) (Authenticated sender: b93043) by smtp.csie.ntu.edu.tw (Postfix) with ESMTPSA id 127F52089B; Fri, 23 Oct 2015 11:50:57 +0800 (CST) Received: by mirror2.csie.ntu.edu.tw (Postfix, from userid 1000) id DE7805F993; Fri, 23 Oct 2015 11:50:56 +0800 (CST) From: Chen-Yu Tsai To: Hans de Goede , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Maxime Ripard Cc: Chen-Yu Tsai , linux-fbdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Mark Brown Subject: [PATCH v4 2/4] simplefb: Claim and enable regulators Date: Fri, 23 Oct 2015 11:50:39 +0800 Message-Id: <1445572241-13259-3-git-send-email-wens@csie.org> X-Mailer: git-send-email 2.6.1 In-Reply-To: <1445572241-13259-1-git-send-email-wens@csie.org> References: <1445572241-13259-1-git-send-email-wens@csie.org> Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This claims and enables regulators listed in the simple framebuffer dt node. This is needed so that regulators powering the display pipeline and external hardware, described in the device node and known by the kernel code, will remain properly enabled. Signed-off-by: Chen-Yu Tsai Acked-by: Mark Brown --- drivers/video/fbdev/simplefb.c | 120 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 119 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/simplefb.c b/drivers/video/fbdev/simplefb.c index 52c5c7e63b52..48ccf6db62a2 100644 --- a/drivers/video/fbdev/simplefb.c +++ b/drivers/video/fbdev/simplefb.c @@ -28,7 +28,10 @@ #include #include #include +#include #include +#include +#include static struct fb_fix_screeninfo simplefb_fix = { .id = "simple", @@ -174,6 +177,10 @@ struct simplefb_par { int clk_count; struct clk **clks; #endif +#if defined CONFIG_OF && defined CONFIG_REGULATOR + u32 regulator_count; + struct regulator **regulators; +#endif }; #if defined CONFIG_OF && defined CONFIG_COMMON_CLK @@ -269,6 +276,110 @@ static int simplefb_clocks_init(struct simplefb_par *par, static void simplefb_clocks_destroy(struct simplefb_par *par) { } #endif +#if defined CONFIG_OF && defined CONFIG_REGULATOR + +#define SUPPLY_SUFFIX "-supply" + +/* + * Regulator handling code. + * + * Here we handle the num-supplies and vin*-supply properties of our + * "simple-framebuffer" dt node. This is necessary so that we can make sure + * that any regulators needed by the display hardware that the bootloader + * set up for us (and for which it provided a simplefb dt node), stay up, + * for the life of the simplefb driver. + * + * When the driver unloads, we cleanly disable, and then release the + * regulators. + * + * We only complain about errors here, no action is taken as the most likely + * error can only happen due to a mismatch between the bootloader which set + * up simplefb, and the regulator definitions in the device tree. Chances are + * that there are no adverse effects, and if there are, a clean teardown of + * the fb probe will not help us much either. So just complain and carry on, + * and hope that the user actually gets a working fb at the end of things. + */ +static int simplefb_regulators_init(struct simplefb_par *par, + struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct property *prop; + struct regulator *regulator; + const char *p; + int count = 0, i = 0, ret; + + if (dev_get_platdata(&pdev->dev) || !np) + return 0; + + /* Count the number of regulator supplies */ + for_each_property_of_node(np, prop) { + p = strstr(prop->name, SUPPLY_SUFFIX); + if (p && p != prop->name) + count++; + } + + if (!count) + return 0; + + par->regulators = devm_kcalloc(&pdev->dev, count, + sizeof(struct regulator *), GFP_KERNEL); + if (!par->regulators) + return -ENOMEM; + + /* Get all the regulators */ + for_each_property_of_node(np, prop) { + char name[32]; /* 32 is max size of property name */ + + p = strstr(prop->name, SUPPLY_SUFFIX); + if (!p || p == prop->name) + continue; + + strlcpy(name, prop->name, + strlen(prop->name) - strlen(SUPPLY_SUFFIX) + 1); + regulator = devm_regulator_get_optional(&pdev->dev, name); + if (IS_ERR(regulator)) { + if (PTR_ERR(regulator) == -EPROBE_DEFER) + return -EPROBE_DEFER; + dev_err(&pdev->dev, "regulator %s not found: %ld\n", + name, PTR_ERR(regulator)); + continue; + } + par->regulators[i++] = regulator; + } + par->regulator_count = i; + + /* Enable all the regulators */ + for (i = 0; i < par->regulator_count; i++) { + ret = regulator_enable(par->regulators[i]); + if (ret) { + dev_err(&pdev->dev, + "failed to enable regulator %d: %d\n", + i, ret); + devm_regulator_put(par->regulators[i]); + par->regulators[i] = NULL; + } + } + + return 0; +} + +static void simplefb_regulators_destroy(struct simplefb_par *par) +{ + int i; + + if (!par->regulators) + return; + + for (i = 0; i < par->regulator_count; i++) + if (par->regulators[i]) + regulator_disable(par->regulators[i]); +} +#else +static int simplefb_regulators_init(struct simplefb_par *par, + struct platform_device *pdev) { return 0; } +static void simplefb_regulators_destroy(struct simplefb_par *par) { } +#endif + static int simplefb_probe(struct platform_device *pdev) { int ret; @@ -340,6 +451,10 @@ static int simplefb_probe(struct platform_device *pdev) if (ret < 0) goto error_unmap; + ret = simplefb_regulators_init(par, pdev); + if (ret < 0) + goto error_clocks; + dev_info(&pdev->dev, "framebuffer at 0x%lx, 0x%x bytes, mapped to 0x%p\n", info->fix.smem_start, info->fix.smem_len, info->screen_base); @@ -351,13 +466,15 @@ static int simplefb_probe(struct platform_device *pdev) ret = register_framebuffer(info); if (ret < 0) { dev_err(&pdev->dev, "Unable to register simplefb: %d\n", ret); - goto error_clocks; + goto error_regulators; } dev_info(&pdev->dev, "fb%d: simplefb registered!\n", info->node); return 0; +error_regulators: + simplefb_regulators_destroy(par); error_clocks: simplefb_clocks_destroy(par); error_unmap: @@ -373,6 +490,7 @@ static int simplefb_remove(struct platform_device *pdev) struct simplefb_par *par = info->par; unregister_framebuffer(info); + simplefb_regulators_destroy(par); simplefb_clocks_destroy(par); framebuffer_release(info);