From patchwork Tue Aug 20 11:13:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aisheng Dong X-Patchwork-Id: 11103625 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E9F721398 for ; Tue, 20 Aug 2019 11:32:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D21FD2082F for ; Tue, 20 Aug 2019 11:32:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729738AbfHTLcR (ORCPT ); Tue, 20 Aug 2019 07:32:17 -0400 Received: from inva020.nxp.com ([92.121.34.13]:55714 "EHLO inva020.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729784AbfHTLcP (ORCPT ); Tue, 20 Aug 2019 07:32:15 -0400 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 594B01A0103; Tue, 20 Aug 2019 13:32:13 +0200 (CEST) Received: from invc005.ap-rdc01.nxp.com (invc005.ap-rdc01.nxp.com [165.114.16.14]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 0A3461A0040; Tue, 20 Aug 2019 13:32:09 +0200 (CEST) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id 3BBCB40326; Tue, 20 Aug 2019 19:32:01 +0800 (SGT) From: Dong Aisheng To: linux-clk@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, sboyd@kernel.org, mturquette@baylibre.com, shawnguo@kernel.org, fabio.estevam@nxp.com, linux-imx@nxp.com, kernel@pengutronix.de, Dong Aisheng Subject: [PATCH V4 11/11] clk: imx: lpcg: add suspend/resume support Date: Tue, 20 Aug 2019 07:13:25 -0400 Message-Id: <1566299605-15641-12-git-send-email-aisheng.dong@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1566299605-15641-1-git-send-email-aisheng.dong@nxp.com> References: <1566299605-15641-1-git-send-email-aisheng.dong@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org LPCG clock state may be lost when it's power domain is completely off during system suspend/resume and we need save and restore the state properly. Signed-off-by: Dong Aisheng --- ChangeLog: v3: new patch --- drivers/clk/imx/clk-imx8qxp-lpcg.c | 1 + drivers/clk/imx/clk-lpcg-scu.c | 33 +++++++++++++++++++++++++++++++++ drivers/clk/imx/clk-scu.h | 1 + 3 files changed, 35 insertions(+) diff --git a/drivers/clk/imx/clk-imx8qxp-lpcg.c b/drivers/clk/imx/clk-imx8qxp-lpcg.c index ca9bd58..885498f 100644 --- a/drivers/clk/imx/clk-imx8qxp-lpcg.c +++ b/drivers/clk/imx/clk-imx8qxp-lpcg.c @@ -338,6 +338,7 @@ static struct platform_driver imx8qxp_lpcg_clk_driver = { .driver = { .name = "imx8qxp-lpcg-clk", .of_match_table = imx8qxp_lpcg_match, + .pm = &imx_clk_lpcg_scu_pm_ops, .suppress_bind_attrs = true, }, .probe = imx8qxp_lpcg_clk_probe, diff --git a/drivers/clk/imx/clk-lpcg-scu.c b/drivers/clk/imx/clk-lpcg-scu.c index 3c092a0..4df0818 100644 --- a/drivers/clk/imx/clk-lpcg-scu.c +++ b/drivers/clk/imx/clk-lpcg-scu.c @@ -33,6 +33,9 @@ struct clk_lpcg_scu { void __iomem *reg; u8 bit_idx; bool hw_gate; + + /* for state save&restore */ + u32 state; }; #define to_clk_lpcg_scu(_hw) container_of(_hw, struct clk_lpcg_scu, hw) @@ -112,5 +115,35 @@ struct clk_hw *__imx_clk_lpcg_scu(struct device *dev, const char *name, hw = ERR_PTR(ret); } + if (dev) + dev_set_drvdata(dev, clk); + return hw; } + +int __maybe_unused imx_clk_lpcg_scu_suspend(struct device *dev) +{ + struct clk_lpcg_scu *clk = dev_get_drvdata(dev); + + clk->state = readl_relaxed(clk->reg); + dev_dbg(dev, "save lpcg state 0x%x\n", clk->state); + + return 0; +} + +int __maybe_unused imx_clk_lpcg_scu_resume(struct device *dev) +{ + struct clk_lpcg_scu *clk = dev_get_drvdata(dev); + + /* FIXME: double write in case a failure */ + writel(clk->state, clk->reg); + writel(clk->state, clk->reg); + dev_dbg(dev, "restore lpcg state 0x%x\n", clk->state); + + return 0; +} + +const struct dev_pm_ops imx_clk_lpcg_scu_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_clk_lpcg_scu_suspend, + imx_clk_lpcg_scu_resume) +}; diff --git a/drivers/clk/imx/clk-scu.h b/drivers/clk/imx/clk-scu.h index 84efda3..6d4b6e2 100644 --- a/drivers/clk/imx/clk-scu.h +++ b/drivers/clk/imx/clk-scu.h @@ -12,6 +12,7 @@ extern u32 clock_cells; extern struct list_head imx_scu_clks[]; +extern const struct dev_pm_ops imx_clk_lpcg_scu_pm_ops; int imx_clk_scu_init(struct device_node *np); struct clk_hw *imx_scu_of_clk_src_get(struct of_phandle_args *clkspec,