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=-7.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 82E5CC33C9B for ; Mon, 6 Jan 2020 13:30:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46FD020731 for ; Mon, 6 Jan 2020 13:30:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=st.com header.i=@st.com header.b="Hlg+3+62" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726830AbgAFNa2 (ORCPT ); Mon, 6 Jan 2020 08:30:28 -0500 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:60623 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726383AbgAFN35 (ORCPT ); Mon, 6 Jan 2020 08:29:57 -0500 Received: from pps.filterd (m0046037.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 006DRNnY015657; Mon, 6 Jan 2020 14:29:43 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=STMicroelectronics; bh=fcQwQK7DhsbJHsH4iVjG86araMbU8oHNqCR0+zSFh5g=; b=Hlg+3+62gXswrbVmCJ/sddrHKt3p/9wz2FijIPGNpL10UAlpwlWAL0rr4QbraDNG/tl7 URGMqwtxRpGmZKBseVhI1aDA5TiN3xvhVOsm9lmrW8vfPNUuqQZHWvdFXVtCj0s4zzQF RFxt8l5BrXdo3pdi1tVUDQff+gEimL2l92GSdmhhnwwEeWh1sky8Y0VoDyAHcybQzkII EW3Ej/ctyreKaZyL41VrGYDeXGggmmbd8usWKNKVO4pg+ALSNRALEo7QhPizRxU5/Up+ zR76UqQhN7K47xViRpBtCB5udqnV31POwPUEl3HcTC+WnduaY+eZl8has1hnSofs977y rg== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 2xakuqg3qp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 06 Jan 2020 14:29:43 +0100 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 6B4DF10002A; Mon, 6 Jan 2020 14:29:43 +0100 (CET) Received: from Webmail-eu.st.com (sfhdag3node2.st.com [10.75.127.8]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 5EBD42D378B; Mon, 6 Jan 2020 14:29:43 +0100 (CET) Received: from localhost (10.75.127.51) by SFHDAG3NODE2.st.com (10.75.127.8) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 6 Jan 2020 14:29:43 +0100 From: Alain Volmat To: , CC: , , , , , , , , , Subject: [PATCH 4/6] i2c: i2c-stm32f7: add PM_SLEEP suspend/resume support Date: Mon, 6 Jan 2020 14:28:32 +0100 Message-ID: <1578317314-17197-5-git-send-email-alain.volmat@st.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1578317314-17197-1-git-send-email-alain.volmat@st.com> References: <1578317314-17197-1-git-send-email-alain.volmat@st.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.75.127.51] X-ClientProxiedBy: SFHDAG8NODE1.st.com (10.75.127.22) To SFHDAG3NODE2.st.com (10.75.127.8) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2020-01-06_04:2020-01-06,2020-01-06 signatures=0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Backup/restore I2C registers as part of the suspend/resume handlers. The device is marked as suspended to ensure that transfers are rejected during the suspended period. Signed-off-by: Pierre-Yves MORDRET Signed-off-by: Alain Volmat --- drivers/i2c/busses/i2c-stm32f7.c | 117 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 113 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index b2634afe066d..5c3e8ac6ad92 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -169,6 +169,24 @@ #define STM32F7_AUTOSUSPEND_DELAY (HZ / 100) /** + * struct stm32f7_i2c_regs - i2c f7 registers backup + * @cr1: Control register 1 + * @cr2: Control register 2 + * @oar1: Own address 1 register + * @oar2: Own address 2 register + * @pecr: PEC register + * @tmgr: Timing register + */ +struct stm32f7_i2c_regs { + u32 cr1; + u32 cr2; + u32 oar1; + u32 oar2; + u32 pecr; + u32 tmgr; +}; + +/** * struct stm32f7_i2c_spec - private i2c specification timing * @rate: I2C bus speed (Hz) * @rate_min: 80% of I2C bus speed (Hz) @@ -276,6 +294,7 @@ struct stm32f7_i2c_msg { * @timing: I2C computed timings * @slave: list of slave devices registered on the I2C bus * @slave_running: slave device currently used + * @backup_regs: backup of i2c controller registers (for suspend/resume) * @slave_dir: transfer direction for the current slave device * @master_mode: boolean to know in which mode the I2C is running (master or * slave) @@ -298,6 +317,7 @@ struct stm32f7_i2c_dev { struct stm32f7_i2c_timings timing; struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE]; struct i2c_client *slave_running; + struct stm32f7_i2c_regs backup_regs; u32 slave_dir; bool master_mode; struct stm32_i2c_dma *dma; @@ -2027,8 +2047,7 @@ static int stm32f7_i2c_remove(struct platform_device *pdev) return 0; } -#ifdef CONFIG_PM -static int stm32f7_i2c_runtime_suspend(struct device *dev) +static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev) { struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); @@ -2038,7 +2057,7 @@ static int stm32f7_i2c_runtime_suspend(struct device *dev) return 0; } -static int stm32f7_i2c_runtime_resume(struct device *dev) +static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev) { struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); int ret; @@ -2053,11 +2072,101 @@ static int stm32f7_i2c_runtime_resume(struct device *dev) return 0; } -#endif + +static int __maybe_unused +stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev) +{ + int ret; + struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) + return ret; + + backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1); + backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); + backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1); + backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2); + backup_regs->pecr = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR); + backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR); + + pm_runtime_put_sync(i2c_dev->dev); + + return ret; +} + +static int __maybe_unused +stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev) +{ + u32 cr1; + int ret; + struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) + return ret; + + cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1); + if (cr1 & STM32F7_I2C_CR1_PE) + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_PE); + + writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR); + writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE, + i2c_dev->base + STM32F7_I2C_CR1); + if (backup_regs->cr1 & STM32F7_I2C_CR1_PE) + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_PE); + writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2); + writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1); + writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2); + writel_relaxed(backup_regs->pecr, i2c_dev->base + STM32F7_I2C_PECR); + + pm_runtime_put_sync(i2c_dev->dev); + + return ret; +} + +static int __maybe_unused stm32f7_i2c_suspend(struct device *dev) +{ + struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int ret; + + i2c_mark_adapter_suspended(&i2c_dev->adap); + ret = stm32f7_i2c_regs_backup(i2c_dev); + if (ret < 0) { + i2c_mark_adapter_resumed(&i2c_dev->adap); + return ret; + } + + pinctrl_pm_select_sleep_state(dev); + pm_runtime_force_suspend(dev); + + return 0; +} + +static int __maybe_unused stm32f7_i2c_resume(struct device *dev) +{ + struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_resume(dev); + if (ret < 0) + return ret; + pinctrl_pm_select_default_state(dev); + + ret = stm32f7_i2c_regs_restore(i2c_dev); + if (ret < 0) + return ret; + i2c_mark_adapter_resumed(&i2c_dev->adap); + + return 0; +} static const struct dev_pm_ops stm32f7_i2c_pm_ops = { SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend, stm32f7_i2c_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume) }; static const struct of_device_id stm32f7_i2c_match[] = { -- 2.7.4