From patchwork Mon Aug 15 21:58:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yassine Oudjana X-Patchwork-Id: 12944096 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 A3372C25B0E for ; Mon, 15 Aug 2022 22:00:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=F2rGFENzHI0E3i8mswF35hHoUMszy0CZxP2MWQKHpBQ=; b=boVWCDEOec94MPRPGztPwk7Ijy 8dLM/LOItY9utuOzKjUrcJz/Gw4l08yp/C7Mr/WxF6kpaCO915czO6Gmupei9ogzsPu79XSUM7XHX gbc+X8JQfDLSScdOH6ecFMabWt90eMQJzfltkWrFzKJ9xaaoSlOVTztp49o7g+93AVbihrFpieB0p P8mhJkc8RY4gNY/5Nex+EQ2JewE+yHK+gHJwhRENdhYPSsJvKTkj9+jZJC8xu3rb7gwiKevTnFVQs r2y9KebmyC0Jar85jHaHyZgun32qAWaB7M8AjHtjhJxfJCaN7IgdmNKZROwFVcAfNxPXJDSDVW6iC EXTXp6TQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oNi89-006LM6-Dc; Mon, 15 Aug 2022 22:00:17 +0000 Received: from mail-wr1-x435.google.com ([2a00:1450:4864:20::435]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oNi85-006LFd-Df; Mon, 15 Aug 2022 22:00:15 +0000 Received: by mail-wr1-x435.google.com with SMTP id j7so10514491wrh.3; Mon, 15 Aug 2022 15:00:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc; bh=F2rGFENzHI0E3i8mswF35hHoUMszy0CZxP2MWQKHpBQ=; b=SwigwelJnmy5DhbwCbX4EIFty2vdJVo6HL901+2tfj45cuM+Dm4xSkjCK5i5aB1ucr BogTShuXqf9zG5AWFiFvUfiIYTKNG+Gg/fdYxyYjBA0kqyQujK08eirJUAS6pF40YghK QHw3mHBtJLp0EJC/vs3bl/khLlZXi1+zp6i+VlHNGVUbEaOwZUEaJpRNj+e44esGtT3J IY6Ljvy2jvT6QOjEJwNIM3fhCw4sSXWsNBGueBXZvsWAf8E3OQ4Q5LdITTsM15uvvpFT oJGa+TnZX7IzahqmWQDHMWYfb701XbLihdRlnBqtunzTIdlATyWMi9NKr58jl2M0mYLM sl9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc; bh=F2rGFENzHI0E3i8mswF35hHoUMszy0CZxP2MWQKHpBQ=; b=U81+9ICSUS1C8o51l/1Sffs/5cuGMYbilJLbthfTZjnvjkVx/zJvAZEl2Dtce7yKEp aZ5AEck2i4xsqK/Lv1uT94SWRHRzAkYVRIUHM7q3owpgkfQC0QKYigwbDlId1LTjMZR9 Qntgy1VFWBdCLpw/SwCeP9BjbKlW2NNz8LUtbCwaj3dXQNdycXnTKPbwKJXfpfuNyLHE mYyUIkOCriUvboaX5pxlyECbAuRcuyXRr8e8l6276m49YzNgsn6flhnQgU8tpvrocX+k fD4tdHE9KibW618HrNV/rtSgW5fGG4dlgemf9RppuEkUEQuCfrQr4e22U/igUv30FWio ymcg== X-Gm-Message-State: ACgBeo2AfQa61eMzUKh6n3r0uFYrMdCOXscFJu+vTx/W+S3MHiFOig3V UHKhFDg1iAeVGu9EtaN3G40= X-Google-Smtp-Source: AA6agR7uQBKz9p2RoPuPctiBHIoYB4Qu2te8eOPpUxlusmYdKqLIHMU/LCxGvX4St+OzDGJl/1h/uw== X-Received: by 2002:adf:dbc1:0:b0:224:fc61:fef7 with SMTP id e1-20020adfdbc1000000b00224fc61fef7mr4956247wrj.312.1660600810584; Mon, 15 Aug 2022 15:00:10 -0700 (PDT) Received: from localhost.localdomain ([105.235.130.28]) by smtp.gmail.com with ESMTPSA id y10-20020adfee0a000000b00223664ab3a8sm10195480wrn.90.2022.08.15.15.00.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Aug 2022 15:00:10 -0700 (PDT) From: Yassine Oudjana X-Google-Original-From: Yassine Oudjana To: Chunfeng Yun , Kishon Vijay Abraham I , Vinod Koul , Matthias Brugger , AngeloGioacchino Del Regno Cc: Yassine Oudjana , Yassine Oudjana , linux-mediatek@lists.infradead.org, linux-phy@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH] phy: phy-mtk-tphy: Make USB PHY work on MT6735 Date: Mon, 15 Aug 2022 22:58:59 +0100 Message-Id: <20220815215859.253962-1-y.oudjana@protonmail.com> X-Mailer: git-send-email 2.37.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220815_150013_507302_9429EA5E X-CRM114-Status: GOOD ( 20.86 ) X-BeenThere: linux-mediatek@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-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org The USB PHY on MT6735 seems to be a TPHY V1, but the FMREG base here is 0xf00 rather than 0x100. Since it is definitely not a V2 or later as it has shared registers, would this mean that it is an even earlier revision, or one between V1 and V2? Or is the address used currently in this driver wrong? Furthermore, there is one additional step needed in the power on sequence to make USB work on MT6735, which is to set the 10th bit of U3P_U2PHYDTM1. This was found through trial and error by adding the power on sequence from the downstream driver then stripping parts of it until a critical part is found. This specific part[1] was found under a comment saying "force enter device mode", but there are other bits that are cleared/set under the same comment, some of which are set in the same write as this bit, so it is unclear whether this bit is the one (or the only one) responsible for "forcing enter device mode". There is no documentation on this register (or any port registers for that matter) so this bit's name and function are unknown. Does anyone have more information on this? And if no information were to be found, would leaving this as a magic value, or with the placeholder name currently used (P2C_FORCE_ENTER_DEVICE_MODE) be acceptable? [1] https://gitlab.com/Tooniis/linux-samsung-grandpplte/-/blob/master/drivers/misc/mediatek/usb20/mt6735/usb20_phy.c#L404 --- drivers/phy/mediatek/phy-mtk-tphy.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c index 8ee7682b8e93..f54b8a9872bf 100644 --- a/drivers/phy/mediatek/phy-mtk-tphy.c +++ b/drivers/phy/mediatek/phy-mtk-tphy.c @@ -23,7 +23,7 @@ /* version V1 sub-banks offset base address */ /* banks shared by multiple phys */ #define SSUSB_SIFSLV_V1_SPLLC 0x000 /* shared by u3 phys */ -#define SSUSB_SIFSLV_V1_U2FREQ 0x100 /* shared by u2 phys */ +#define SSUSB_SIFSLV_V1_U2FREQ 0xf00 /* shared by u2 phys */ #define SSUSB_SIFSLV_V1_CHIP 0x300 /* shared by u3 phys */ /* u2 phy bank */ #define SSUSB_SIFSLV_V1_U2PHY_COM 0x000 @@ -119,6 +119,7 @@ #define U3P_U2PHYDTM1 0x06C #define P2C_RG_UART_EN BIT(16) +#define P2C_FORCE_ENTER_DEVICE_MODE BIT(10) #define P2C_FORCE_IDDIG BIT(9) #define P2C_RG_VBUSVALID BIT(5) #define P2C_RG_SESSEND BIT(4) @@ -579,6 +580,8 @@ static void u2_phy_instance_power_on(struct mtk_tphy *tphy, mtk_phy_set_bits(com + U3P_U2PHYDTM0, P2C_RG_SUSPENDM | P2C_FORCE_SUSPENDM); } dev_dbg(tphy->dev, "%s(%d)\n", __func__, index); + + mtk_phy_set_bits(com + U3P_U2PHYDTM1, P2C_FORCE_ENTER_DEVICE_MODE); } static void u2_phy_instance_power_off(struct mtk_tphy *tphy,