From patchwork Fri Sep 28 12:59:11 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 11847 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 8368824146 for ; Fri, 28 Sep 2012 12:59:37 +0000 (UTC) Received: from mail-ie0-f180.google.com (mail-ie0-f180.google.com [209.85.223.180]) by fiordland.canonical.com (Postfix) with ESMTP id 11442A18D13 for ; Fri, 28 Sep 2012 12:59:36 +0000 (UTC) Received: by ieje10 with SMTP id e10so6791519iej.11 for ; Fri, 28 Sep 2012 05:59:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-forwarded-to:x-forwarded-for:delivered-to:received-spf:from:to:cc :subject:date:message-id:x-mailer:mime-version:content-type :x-gm-message-state; bh=Y98cBv9fEKE0C9zc0NTAARy9CVRFRjexoCT5/6IQafs=; b=mkJiC0C2eA2whfBK0xE0Mcgt0mApN+e595wmUH6wyZoRppGT81aBuq98N+KmvPGpKV VOwtJ9YyHI2aiwF7hVRonKcnzwYikQzr3StCLupdOdiAvtTMCH9ZrmK2gFjTqk6edjyz +ts5+HSYMyFo+aQxlJ5KVTw7M6t2C7l3Szehzbo9CZSnlYUyGafJtb1ftbYTMlxA/5RA YQBXWXf7o7MKAj7pECyoBdcJ1nkXB4tVBw9aTehgH8IXKpk6tPRr5ygeGmfFrcnofz+w daIaF5YnbBEbQI1aYnm6XfsFVeFgH6yr7EZnukHtk2kVdesMNdE+bZxNDjnM1IIJvkpt Ndwg== Received: by 10.50.194.136 with SMTP id hw8mr1025548igc.28.1348837176389; Fri, 28 Sep 2012 05:59:36 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.50.184.232 with SMTP id ex8csp470585igc; Fri, 28 Sep 2012 05:59:35 -0700 (PDT) Received: by 10.14.218.134 with SMTP id k6mr9978146eep.14.1348837174299; Fri, 28 Sep 2012 05:59:34 -0700 (PDT) Received: from eu1sys200aog120.obsmtp.com (eu1sys200aog120.obsmtp.com [207.126.144.149]) by mx.google.com with SMTP id 42si7360748eee.72.2012.09.28.05.59.28 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 28 Sep 2012 05:59:34 -0700 (PDT) Received-SPF: neutral (google.com: 207.126.144.149 is neither permitted nor denied by best guess record for domain of linus.walleij@stericsson.com) client-ip=207.126.144.149; Authentication-Results: mx.google.com; spf=neutral (google.com: 207.126.144.149 is neither permitted nor denied by best guess record for domain of linus.walleij@stericsson.com) smtp.mail=linus.walleij@stericsson.com Received: from beta.dmz-ap.st.com ([138.198.100.35]) (using TLSv1) by eu1sys200aob120.postini.com ([207.126.147.11]) with SMTP ID DSNKUGWfLzEsxsiZ77T43ckHGb7SiefzJsNk@postini.com; Fri, 28 Sep 2012 12:59:33 UTC Received: from zeta.dmz-ap.st.com (ns6.st.com [138.198.234.13]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id 7D435AB; Fri, 28 Sep 2012 12:51:09 +0000 (GMT) Received: from relay2.stm.gmessaging.net (unknown [10.230.100.18]) by zeta.dmz-ap.st.com (STMicroelectronics) with ESMTP id E12341061; Fri, 28 Sep 2012 12:59:21 +0000 (GMT) Received: from exdcvycastm022.EQ1STM.local (alteon-source-exch [10.230.100.61]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (Client CN "exdcvycastm022", Issuer "exdcvycastm022" (not verified)) by relay2.stm.gmessaging.net (Postfix) with ESMTPS id CBC2DA8065; Fri, 28 Sep 2012 14:59:15 +0200 (CEST) Received: from steludxu4075.lud.stericsson.com (10.230.100.153) by smtp.stericsson.com (10.230.100.30) with Microsoft SMTP Server (TLS) id 8.3.83.0; Fri, 28 Sep 2012 14:59:20 +0200 From: Linus Walleij To: Ben Dooks , Wolfram Sang , Cc: Anmar Oueja , Patrice Chotard , Linus Walleij Subject: [PATCH v2] i2c: nomadik: adopt pinctrl support Date: Fri, 28 Sep 2012 14:59:11 +0200 Message-ID: <1348837151-20820-1-git-send-email-linus.walleij@stericsson.com> X-Mailer: git-send-email 1.7.11.3 MIME-Version: 1.0 X-Gm-Message-State: ALoCoQlxzgnDN0yFLUTSAZs0oCLjuh2nKJJTtQQxNIQtnKhe87FqsCFE+VIW8NOaKzfDa3cG1Gnc From: Patrice Chotard Amend the I2C nomadik 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() This should make it possible to optimize energy usage for the pins both for the suspend/resume cycle, and for runtime cases inbetween I2C transfers. Signed-off-by: Patrice Chotard Signed-off-by: Linus Walleij --- ChangeLog v1->v2: - We used only two states initially: default and sleep. It turns out you can save some energy when idling (between transfers) and even more when suspending on our platform, so grab all three states and use them as applicable. --- drivers/i2c/busses/i2c-nomadik.c | 102 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c index 1b898b6..bd3da46 100644 --- a/drivers/i2c/busses/i2c-nomadik.c +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -24,6 +24,7 @@ #include #include #include +#include #define DRIVER_NAME "nmk-i2c" @@ -145,6 +146,10 @@ struct i2c_nmk_client { * @stop: stop condition. * @xfer_complete: acknowledge completion for a I2C message. * @result: controller propogated result. + * @pinctrl: pinctrl handle. + * @pins_default: default state for the pins. + * @pins_idle: idle state for the pins. + * @pins_sleep: sleep state for the pins. * @busy: Busy doing transfer. */ struct nmk_i2c_dev { @@ -158,6 +163,11 @@ struct nmk_i2c_dev { int stop; struct completion xfer_complete; int result; + /* Three pin states - default, idle & sleep */ + struct pinctrl *pinctrl; + struct pinctrl_state *pins_default; + struct pinctrl_state *pins_idle; + struct pinctrl_state *pins_sleep; bool busy; }; @@ -642,6 +652,15 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, pm_runtime_get_sync(&dev->adev->dev); + /* Optionaly enable pins to be muxed in and configured */ + if (!IS_ERR(dev->pins_default)) { + status = pinctrl_select_state(dev->pinctrl, + dev->pins_default); + if (status) + dev_err(&dev->adev->dev, + "could not set default pins\n"); + } + clk_enable(dev->clk); status = init_hw(dev); @@ -670,6 +689,16 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, out: clk_disable(dev->clk); + + /* Optionally let pins go into idle state */ + if (!IS_ERR(dev->pins_idle)) { + status = pinctrl_select_state(dev->pinctrl, + dev->pins_idle); + if (status) + dev_err(&dev->adev->dev, + "could not set pins to idle state\n"); + } + pm_runtime_put_sync(&dev->adev->dev); dev->busy = false; @@ -864,15 +893,44 @@ static int nmk_i2c_suspend(struct device *dev) { struct amba_device *adev = to_amba_device(dev); struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev); + int ret; if (nmk_i2c->busy) return -EBUSY; + if (!IS_ERR(nmk_i2c->pins_sleep)) { + ret = pinctrl_select_state(nmk_i2c->pinctrl, + nmk_i2c->pins_sleep); + if (ret) + dev_err(dev, + "could not set pins to sleep state\n"); + } + return 0; } static int nmk_i2c_resume(struct device *dev) { + struct amba_device *adev = to_amba_device(dev); + struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev); + int ret; + + /* First go to the default state */ + if (!IS_ERR(nmk_i2c->pins_default)) { + ret = pinctrl_select_state(nmk_i2c->pinctrl, + nmk_i2c->pins_default); + if (ret) + 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(nmk_i2c->pins_idle)) { + ret = pinctrl_select_state(nmk_i2c->pinctrl, + nmk_i2c->pins_idle); + if (ret) + dev_err(dev, + "could not set pins to idle state\n"); + } return 0; } #else @@ -936,6 +994,40 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) dev->adev = adev; amba_set_drvdata(adev, dev); + dev->pinctrl = devm_pinctrl_get(&adev->dev); + if (IS_ERR(dev->pinctrl)) { + ret = PTR_ERR(dev->pinctrl); + goto err_pinctrl; + } + + dev->pins_default = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_DEFAULT); + if (IS_ERR(dev->pins_default)) + dev_err(&adev->dev, "could not get default pinstate\n"); + else { + ret = pinctrl_select_state(dev->pinctrl, + dev->pins_default); + if (ret) + dev_dbg(&adev->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(&adev->dev, "could not get idle pinstate\n"); + else { + /* If possible, let's go to idle until the first transfer */ + ret = pinctrl_select_state(dev->pinctrl, + dev->pins_idle); + if (ret) + dev_dbg(&adev->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(&adev->dev, "could not get sleep pinstate\n"); + dev->virtbase = ioremap(adev->res.start, resource_size(&adev->res)); if (!dev->virtbase) { ret = -ENOMEM; @@ -959,6 +1051,12 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) goto err_no_clk; } + ret = clk_prepare(dev->clk); + if (ret) { + dev_err(&adev->dev, "can't prepare clock\n"); + goto err_prep_clk; + } + adap = &dev->adap; adap->dev.parent = &adev->dev; adap->owner = THIS_MODULE; @@ -994,6 +1092,8 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) return 0; err_add_adap: + clk_unprepare(dev->clk); + err_prep_clk: clk_put(dev->clk); err_no_clk: free_irq(dev->irq, dev); @@ -1002,6 +1102,7 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) err_no_ioremap: amba_set_drvdata(adev, NULL); kfree(dev); + err_pinctrl: err_no_mem: return ret; @@ -1022,6 +1123,7 @@ static int nmk_i2c_remove(struct amba_device *adev) iounmap(dev->virtbase); if (res) release_mem_region(res->start, resource_size(res)); + clk_unprepare(dev->clk); clk_put(dev->clk); pm_runtime_disable(&adev->dev); amba_set_drvdata(adev, NULL);