From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,UNWANTED_LANGUAGE_BODY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF233C76191 for ; Fri, 19 Jul 2019 02:59:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BBA7F2184E for ; Fri, 19 Jul 2019 02:59:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726542AbfGSC74 (ORCPT ); Thu, 18 Jul 2019 22:59:56 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:58182 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726015AbfGSC74 (ORCPT ); Thu, 18 Jul 2019 22:59:56 -0400 X-UUID: b46f2d8561aa45c9ae2e0868a59a8ce5-20190719 X-UUID: b46f2d8561aa45c9ae2e0868a59a8ce5-20190719 Received: from mtkcas06.mediatek.inc [(172.21.101.30)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 1746597379; Fri, 19 Jul 2019 10:59:47 +0800 Received: from mtkcas09.mediatek.inc (172.21.101.178) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 19 Jul 2019 10:59:45 +0800 Received: from localhost.localdomain (10.17.3.153) by mtkcas09.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Fri, 19 Jul 2019 10:59:45 +0800 From: Changqi Hu To: Greg Kroah-Hartman , Jiri Slaby , Matthias Brugger CC: Changqi Hu , Peter Shih , "Gustavo A. R. Silva" , , , , , , Eddie Huang , Yingjoe Chen Subject: [PATCH v3] serial: 8250-mtk: modify mtk uart power and clock management Date: Fri, 19 Jul 2019 10:59:42 +0800 Message-ID: <1563505182-2408-1-git-send-email-changqi.hu@mediatek.com> X-Mailer: git-send-email 1.8.1.1.dirty MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org modify mtk uart runtime interface, add uart clock use count. merge patch v1 and patch v2 together. Signed-off-by: Changqi Hu --- drivers/tty/serial/8250/8250_mtk.c | 50 ++++++++++++++++++++++++-------------- 1 file changed, 32 insertions(+), 18 deletions(-) diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c index f470ded..a07c8ae 100644 --- a/drivers/tty/serial/8250/8250_mtk.c +++ b/drivers/tty/serial/8250/8250_mtk.c @@ -31,6 +31,7 @@ #define MTK_UART_RXTRI_AD 0x14 /* RX Trigger address */ #define MTK_UART_FRACDIV_L 0x15 /* Fractional divider LSB address */ #define MTK_UART_FRACDIV_M 0x16 /* Fractional divider MSB address */ +#define MTK_UART_DEBUG0 0x18 #define MTK_UART_IER_XOFFI 0x20 /* Enable XOFF character interrupt */ #define MTK_UART_IER_RTSI 0x40 /* Enable RTS Modem status interrupt */ #define MTK_UART_IER_CTSI 0x80 /* Enable CTS Modem status interrupt */ @@ -386,9 +387,18 @@ static void mtk8250_set_flow_ctrl(struct uart_8250_port *up, int mode) static int __maybe_unused mtk8250_runtime_suspend(struct device *dev) { struct mtk8250_data *data = dev_get_drvdata(dev); + struct uart_8250_port *up = serial8250_get_port(data->line); - clk_disable_unprepare(data->uart_clk); - clk_disable_unprepare(data->bus_clk); + /* wait until UART in idle status */ + while + (serial_in(up, MTK_UART_DEBUG0)); + + if (data->clk_count == 0U) { + dev_dbg(dev, "%s clock count is 0\n", __func__); + } else { + clk_disable_unprepare(data->bus_clk); + data->clk_count--; + } return 0; } @@ -398,16 +408,16 @@ static int __maybe_unused mtk8250_runtime_resume(struct device *dev) struct mtk8250_data *data = dev_get_drvdata(dev); int err; - err = clk_prepare_enable(data->uart_clk); - if (err) { - dev_warn(dev, "Can't enable clock\n"); - return err; - } - - err = clk_prepare_enable(data->bus_clk); - if (err) { - dev_warn(dev, "Can't enable bus clock\n"); - return err; + if (data->clk_count > 0U) { + dev_dbg(dev, "%s clock count is %d\n", __func__, + data->clk_count); + } else { + err = clk_prepare_enable(data->bus_clk); + if (err) { + dev_warn(dev, "Can't enable bus clock\n"); + return err; + } + data->clk_count++; } return 0; @@ -417,12 +427,14 @@ static int __maybe_unused mtk8250_runtime_resume(struct device *dev) mtk8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old) { if (!state) - pm_runtime_get_sync(port->dev); + if (!mtk8250_runtime_resume(port->dev)) + pm_runtime_get_sync(port->dev); serial8250_do_pm(port, state, old); if (state) - pm_runtime_put_sync_suspend(port->dev); + if (!pm_runtime_put_sync_suspend(port->dev)) + mtk8250_runtime_suspend(port->dev); } #ifdef CONFIG_SERIAL_8250_DMA @@ -499,6 +511,8 @@ static int mtk8250_probe(struct platform_device *pdev) if (!data) return -ENOMEM; + data->clk_count = 0; + if (pdev->dev.of_node) { err = mtk8250_probe_of(pdev, &uart.port, data); if (err) @@ -531,6 +545,7 @@ static int mtk8250_probe(struct platform_device *pdev) platform_set_drvdata(pdev, data); + pm_runtime_enable(&pdev->dev); err = mtk8250_runtime_resume(&pdev->dev); if (err) return err; @@ -539,9 +554,6 @@ static int mtk8250_probe(struct platform_device *pdev) if (data->line < 0) return data->line; - pm_runtime_set_active(&pdev->dev); - pm_runtime_enable(&pdev->dev); - return 0; } @@ -552,11 +564,13 @@ static int mtk8250_remove(struct platform_device *pdev) pm_runtime_get_sync(&pdev->dev); serial8250_unregister_port(data->line); - mtk8250_runtime_suspend(&pdev->dev); pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + mtk8250_runtime_suspend(&pdev->dev); + return 0; } -- 1.8.1.1.dirty