From patchwork Sun Aug 28 08:13:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biju Das X-Patchwork-Id: 12957203 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 3008DECAAD2 for ; Sun, 28 Aug 2022 08:13:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232224AbiH1IN6 (ORCPT ); Sun, 28 Aug 2022 04:13:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232177AbiH1IN4 (ORCPT ); Sun, 28 Aug 2022 04:13:56 -0400 Received: from relmlie6.idc.renesas.com (relmlor2.renesas.com [210.160.252.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3E582286EF; Sun, 28 Aug 2022 01:13:54 -0700 (PDT) X-IronPort-AV: E=Sophos;i="5.93,270,1654527600"; d="scan'208";a="132818631" Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie6.idc.renesas.com with ESMTP; 28 Aug 2022 17:13:54 +0900 Received: from localhost.localdomain (unknown [10.226.92.45]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id DBBD841DDB17; Sun, 28 Aug 2022 17:13:49 +0900 (JST) From: Biju Das To: Mauro Carvalho Chehab , Philipp Zabel Cc: Biju Das , Laurent Pinchart , Kieran Bingham , linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Geert Uytterhoeven , Chris Paterson , Biju Das , Prabhakar Mahadev Lad Subject: [PATCH v14 2/5] media: renesas: vsp1: Add support to deassert/assert reset line Date: Sun, 28 Aug 2022 09:13:31 +0100 Message-Id: <20220828081334.30078-3-biju.das.jz@bp.renesas.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220828081334.30078-1-biju.das.jz@bp.renesas.com> References: <20220828081334.30078-1-biju.das.jz@bp.renesas.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org As the resets DT property is mandatory, and is present in all .dtsi in mainline, add support to perform deassert/assert using reference counted reset handle. Signed-off-by: Biju Das Reviewed-by: Lad Prabhakar Reviewed-by: Geert Uytterhoeven Reviewed-by: Philipp Zabel Reviewed-by: Laurent Pinchart --- v13->v14: * Added Rb tag from Philipp and Laurent. * Updated comment flow. * Changed unconditional delay-> conditional delay for register access after deassert only for Gen2 SoCs. Note: There is no such delay required for accessing VI6_IP_VERSION register (0x3f00). But accessing registers like VI6_STATUS(0x38) needs some delay after deassert. v12->v13: * Removed unused iopoll.h header file. * Added Rb tag from Geert. v11->v12: * Replaced read_poll_timeout_atomic-> udelay(1) as testing on RZ/G1N shows this delay is sufficient to avoid lock-up. * Removed Rb tags. v10->v11: * To avoid lock-up on R-Car Gen2, added poll for reset status after deassert. v9->v10: * Moved {deassert,assert} calls to vsp1_pm_runtime_{resume,suspend} v8->v9: * No change v7->v8: * No Change v6->v7: * No change v5->v6: * Rebased to media_staging and updated commit header * Added Rb tag from Laurent * Added forward declaration for struct reset_control * Updated vsp1_device_get() with changes suggested by Laurent * Updated error message for reset_control_get form ctrl->control. v4->v5: * Added Rb tag from Geert v3->v4: * Restored error check for pm_runtime_resume_and_get and calls assert() in case of failure. v2->v3: * Added Rb tag from Philipp * If reset_control_deassert() failed, return ret directly. v1->v2: * Used reference counted reset handle to perform deassert/assert RFC->v1: * Added reset support as separate patch * Moved rstc just after the bus_master field in struct vsp1_device RFC: * https://patchwork.kernel.org/project/linux-renesas-soc/patch/20220112174612.10773-21-biju.das.jz@bp.renesas.com/ --- drivers/media/platform/renesas/vsp1/vsp1.h | 2 ++ .../media/platform/renesas/vsp1/vsp1_drv.c | 29 +++++++++++++++++-- 2 files changed, 29 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/renesas/vsp1/vsp1.h b/drivers/media/platform/renesas/vsp1/vsp1.h index 37cf33c7e6ca..baf898d577ec 100644 --- a/drivers/media/platform/renesas/vsp1/vsp1.h +++ b/drivers/media/platform/renesas/vsp1/vsp1.h @@ -22,6 +22,7 @@ struct clk; struct device; struct rcar_fcp_device; +struct reset_control; struct vsp1_drm; struct vsp1_entity; @@ -79,6 +80,7 @@ struct vsp1_device { void __iomem *mmio; struct rcar_fcp_device *fcp; struct device *bus_master; + struct reset_control *rstc; struct vsp1_brx *brs; struct vsp1_brx *bru; diff --git a/drivers/media/platform/renesas/vsp1/vsp1_drv.c b/drivers/media/platform/renesas/vsp1/vsp1_drv.c index 1f73c48eb738..ef4bcf860923 100644 --- a/drivers/media/platform/renesas/vsp1/vsp1_drv.c +++ b/drivers/media/platform/renesas/vsp1/vsp1_drv.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -622,6 +623,7 @@ static int __maybe_unused vsp1_pm_runtime_suspend(struct device *dev) struct vsp1_device *vsp1 = dev_get_drvdata(dev); rcar_fcp_disable(vsp1->fcp); + reset_control_assert(vsp1->rstc); return 0; } @@ -631,13 +633,31 @@ static int __maybe_unused vsp1_pm_runtime_resume(struct device *dev) struct vsp1_device *vsp1 = dev_get_drvdata(dev); int ret; + ret = reset_control_deassert(vsp1->rstc); + if (ret < 0) + return ret; + if (vsp1->info) { + /* + * On R-Car Gen2 and RZ/G1, vsp1 register access after deassert + * can cause lock-up. It is a special case and needs some delay + * to avoid this lock-up. + */ + if (vsp1->info->gen == 2) + udelay(1); + ret = vsp1_device_init(vsp1); if (ret < 0) - return ret; + goto done; } - return rcar_fcp_enable(vsp1->fcp); + ret = rcar_fcp_enable(vsp1->fcp); + +done: + if (ret < 0) + reset_control_assert(vsp1->rstc); + + return ret; } static const struct dev_pm_ops vsp1_pm_ops = { @@ -825,6 +845,11 @@ static int vsp1_probe(struct platform_device *pdev) if (irq < 0) return irq; + vsp1->rstc = devm_reset_control_get_shared(&pdev->dev, NULL); + if (IS_ERR(vsp1->rstc)) + return dev_err_probe(&pdev->dev, PTR_ERR(vsp1->rstc), + "failed to get reset control\n"); + /* FCP (optional). */ fcp_node = of_parse_phandle(pdev->dev.of_node, "renesas,fcp", 0); if (fcp_node) {