From patchwork Fri May 31 10:13:11 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Hebbar, Gururaja" X-Patchwork-Id: 2642101 Return-Path: X-Original-To: patchwork-davinci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from bear.ext.ti.com (bear.ext.ti.com [192.94.94.41]) by patchwork2.kernel.org (Postfix) with ESMTP id 7DA58DFB79 for ; Fri, 31 May 2013 10:17:02 +0000 (UTC) Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id r4VAFMMB025084; Fri, 31 May 2013 05:15:22 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r4VAFMpS012535; Fri, 31 May 2013 05:15:22 -0500 Received: from dlelxv24.itg.ti.com (172.17.1.199) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Fri, 31 May 2013 05:15:22 -0500 Received: from linux.omap.com (dlelxs01.itg.ti.com [157.170.227.31]) by dlelxv24.itg.ti.com (8.13.8/8.13.8) with ESMTP id r4VAFM2Q022076; Fri, 31 May 2013 05:15:22 -0500 Received: from linux.omap.com (localhost [127.0.0.1]) by linux.omap.com (Postfix) with ESMTP id 4CD398062F; Fri, 31 May 2013 05:15:22 -0500 (CDT) X-Original-To: davinci-linux-open-source@linux.davincidsp.com Delivered-To: davinci-linux-open-source@linux.davincidsp.com Received: from dlelxv90.itg.ti.com (dlelxv90.itg.ti.com [172.17.2.17]) by linux.omap.com (Postfix) with ESMTP id DDEA480633 for ; Fri, 31 May 2013 05:11:25 -0500 (CDT) Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r4VABPqM003728; Fri, 31 May 2013 05:11:25 -0500 Received: from dlelxv23.itg.ti.com (172.17.1.198) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Fri, 31 May 2013 05:11:25 -0500 Received: from ucmsshproxy.india.ext.ti.com (dbdp20.itg.ti.com [172.24.170.38]) by dlelxv23.itg.ti.com (8.13.8/8.13.8) with SMTP id r4VABI3E005912; Fri, 31 May 2013 05:11:19 -0500 Received: from symphony.india.ext.ti.com (unknown [192.168.247.13]) by ucmsshproxy.india.ext.ti.com (Postfix) with ESMTP id BB8DF158005; Fri, 31 May 2013 15:41:17 +0530 (IST) Received: from ubuntu-psp-linux.india.ext.ti.com (ubuntu-psp-linux [192.168.247.46]) by symphony.india.ext.ti.com (8.11.7p1+Sun/8.11.7) with ESMTP id r4VABGR05862; Fri, 31 May 2013 15:41:16 +0530 (IST) From: Hebbar Gururaja To: , , , Subject: [PATCH 11/11] i2c: omap: enhance pinctrl support Date: Fri, 31 May 2013 15:43:11 +0530 Message-ID: <1369995191-20855-12-git-send-email-gururaja.hebbar@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1369995191-20855-1-git-send-email-gururaja.hebbar@ti.com> References: <1369995191-20855-1-git-send-email-gururaja.hebbar@ti.com> MIME-Version: 1.0 CC: , , Wolfram Sang , Tony Lindgren , , , , , X-BeenThere: davinci-linux-open-source@linux.davincidsp.com X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: Errors-To: davinci-linux-open-source-bounces@linux.davincidsp.com Amend the I2C omap pin controller to optionally take a pin control handle and set the state of the pins to: - "default" on boot, resume and before performing an i2c transfer - "idle" after initial default, after resume default, and after each i2c xfer - "sleep" on suspend() By optionally putting the pins into sleep state in the suspend callback we can accomplish two things. - One is to minimize current leakage from pins and thus save power, - second, we can prevent the IP from driving pins output in an uncontrolled manner, which may happen if the power domain drops the domain regulator. Note: A .suspend & .resume callback is added which simply puts the pins to sleep state upon suspend & are moved to default & idle state upon resume. If any of the above pin states are missing in dt, a warning message about the missing state is displayed. If certain pin-states are not available, to remove this warning message pass respective state name with null phandler. (Changes based on i2c-nomadik.c) Signed-off-by: Hebbar Gururaja Cc: Tony Lindgren Cc: Wolfram Sang Cc: linux-omap@vger.kernel.org Cc: linux-i2c@vger.kernel.org --- :100644 100644 e02f9e3... 588ba28... M drivers/i2c/busses/i2c-omap.c drivers/i2c/busses/i2c-omap.c | 112 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 105 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index e02f9e3..588ba28 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -214,7 +214,11 @@ struct omap_i2c_dev { u16 westate; u16 errata; - struct pinctrl *pins; + /* Three pin states - default, idle & sleep */ + struct pinctrl *pinctrl; + struct pinctrl_state *pins_default; + struct pinctrl_state *pins_idle; + struct pinctrl_state *pins_sleep; }; static const u8 reg_map_ip_v1[] = { @@ -641,6 +645,11 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) if (IS_ERR_VALUE(r)) goto out; + /* Optionaly enable pins to be muxed in and configured */ + if (!IS_ERR(dev->pins_default)) + if (pinctrl_select_state(dev->pinctrl, dev->pins_default)) + dev_err(dev->dev, "could not set default pins\n"); + r = omap_i2c_wait_for_bb(dev); if (r < 0) goto out; @@ -664,7 +673,13 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) out: pm_runtime_mark_last_busy(dev->dev); + pm_runtime_put_autosuspend(dev->dev); + /* Optionally let pins go into idle state */ + if (!IS_ERR(dev->pins_idle)) + if (pinctrl_select_state(dev->pinctrl, dev->pins_idle)) + dev_err(dev->dev, "could not set pins to idle state\n"); + return r; } @@ -1123,14 +1138,47 @@ omap_i2c_probe(struct platform_device *pdev) dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat; } - dev->pins = devm_pinctrl_get_select_default(&pdev->dev); - if (IS_ERR(dev->pins)) { - if (PTR_ERR(dev->pins) == -EPROBE_DEFER) + dev->pinctrl = devm_pinctrl_get(&pdev->dev); + if (!IS_ERR(dev->pinctrl)) { + dev->pins_default = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_DEFAULT); + if (IS_ERR(dev->pins_default)) + dev_dbg(&pdev->dev, "could not get default pinstate\n"); + else + if (pinctrl_select_state(dev->pinctrl, + dev->pins_default)) + dev_err(&pdev->dev, + "could not set default pinstate\n"); + + dev->pins_idle = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_IDLE); + if (IS_ERR(dev->pins_idle)) + dev_dbg(&pdev->dev, "could not get idle pinstate\n"); + else + /* If possible, let's idle until the first transfer */ + if (pinctrl_select_state(dev->pinctrl, dev->pins_idle)) + dev_err(&pdev->dev, + "could not set idle pinstate\n"); + + dev->pins_sleep = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_SLEEP); + if (IS_ERR(dev->pins_sleep)) + dev_dbg(&pdev->dev, "could not get sleep pinstate\n"); + } else { + if (PTR_ERR(dev->pinctrl) == -EPROBE_DEFER) return -EPROBE_DEFER; - dev_warn(&pdev->dev, "did not get pins for i2c error: %li\n", - PTR_ERR(dev->pins)); - dev->pins = NULL; + /* + * Since we continue even when pinctrl node is not found, + * Invalidate pins as not available. This is to make sure that + * IS_ERR(pins_xxx) results in failure when used. + */ + dev->pins_default = ERR_PTR(-ENODATA); + dev->pins_idle = ERR_PTR(-ENODATA); + dev->pins_sleep = ERR_PTR(-ENODATA); + + dev_dbg(&pdev->dev, "did not get pins for i2c error: %li\n", + PTR_ERR(dev->pinctrl)); } dev->dev = &pdev->dev; @@ -1300,6 +1348,10 @@ static int omap_i2c_runtime_suspend(struct device *dev) omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG); } + if (!IS_ERR(_dev->pins_idle)) + if (pinctrl_select_state(_dev->pinctrl, _dev->pins_idle)) + dev_err(dev, "could not set pins to idle state\n"); + return 0; } @@ -1311,13 +1363,59 @@ static int omap_i2c_runtime_resume(struct device *dev) if (!_dev->regs) return 0; + /* Optionally place the pins to the default state */ + if (!IS_ERR(_dev->pins_default)) + if (pinctrl_select_state(_dev->pinctrl, _dev->pins_default)) + dev_err(dev, "could not set pins to default state\n"); + __omap_i2c_init(_dev); return 0; } #endif /* CONFIG_PM_RUNTIME */ +#ifdef CONFIG_PM_SLEEP +static int omap_i2c_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); + + pm_runtime_get_sync(dev); + if (omap_i2c_wait_for_bb(_dev) < 0) { + pm_runtime_put_sync(dev); + return -EBUSY; + } + pm_runtime_put_sync(dev); + + if (!IS_ERR(_dev->pins_sleep)) + if (pinctrl_select_state(_dev->pinctrl, _dev->pins_sleep)) + dev_err(dev, "could not set pins to sleep state\n"); + + return 0; +} + +static int omap_i2c_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); + + /* First go to the default state */ + if (!IS_ERR(_dev->pins_default)) + if (pinctrl_select_state(_dev->pinctrl, _dev->pins_default)) + dev_err(dev, "could not set pins to default state\n"); + + /* Then let's idle the pins until the next transfer happens */ + if (!IS_ERR(_dev->pins_idle)) + if (pinctrl_select_state(_dev->pinctrl, _dev->pins_idle)) + dev_err(dev, "could not set pins to idle state\n"); + + return 0; +} +#endif + + static struct dev_pm_ops omap_i2c_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, omap_i2c_resume) SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend, omap_i2c_runtime_resume, NULL) };