From patchwork Mon Jan 12 04:34:01 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 5607821 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 9B8AF9F358 for ; Mon, 12 Jan 2015 04:34:40 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B4E632039E for ; Mon, 12 Jan 2015 04:34:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE9D820649 for ; Mon, 12 Jan 2015 04:34:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750846AbbALEe1 (ORCPT ); Sun, 11 Jan 2015 23:34:27 -0500 Received: from smtp.csie.ntu.edu.tw ([140.112.30.61]:44975 "EHLO smtp.csie.ntu.edu.tw" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750887AbbALEeV (ORCPT ); Sun, 11 Jan 2015 23:34:21 -0500 Received: from mirror2.csie.ntu.edu.tw (mirror2.csie.ntu.edu.tw [140.112.30.76]) (Authenticated sender: b93043) by smtp.csie.ntu.edu.tw (Postfix) with ESMTPSA id 184582091A; Mon, 12 Jan 2015 12:34:16 +0800 (CST) Received: by mirror2.csie.ntu.edu.tw (Postfix, from userid 1000) id ED3175F7AF; Mon, 12 Jan 2015 12:34:15 +0800 (CST) From: Chen-Yu Tsai To: Maxime Ripard , Dmitry Torokhov , Zhang Rui , Eduardo Valentin Cc: Chen-Yu Tsai , Hans de Goede , linux-input@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org Subject: [PATCH v3 1/9] Input: sun4i-ts: Add thermal zone sensor support Date: Mon, 12 Jan 2015 12:34:01 +0800 Message-Id: <1421037249-28461-2-git-send-email-wens@csie.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1421037249-28461-1-git-send-email-wens@csie.org> References: <1421037249-28461-1-git-send-email-wens@csie.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The touchscreen controller has a temperature sensor embedded in the SoC, which already has hwmon support in the driver. Add DT thermal zone support so we can use it with cpufreq for thermal throttling. This also adds a comment stating that we do not know the actual formula for calculating the temperature. Signed-off-by: Chen-Yu Tsai Acked-by: Eduardo Valentin --- changes since v2: - Use common function for temperature calculation changes since v1: - clean up thermal zone sensor when input device register fails - unconditionally unregister thermal zone sensor on removal. the unregister function checks the pointers passed in. - add comment explaining the lack of documents for the temperature calculation formula --- .../bindings/input/touchscreen/sun4i.txt | 2 + drivers/input/touchscreen/sun4i-ts.c | 54 ++++++++++++++++++++-- 2 files changed, 52 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt index aef57791f40b..a8405bab6c00 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/sun4i.txt @@ -5,6 +5,7 @@ Required properties: - compatible: "allwinner,sun4i-a10-ts" - reg: mmio address range of the chip - interrupts: interrupt to which the chip is connected + - #thermal-sensor-cells: shall be 0 Optional properties: - allwinner,ts-attached: boolean indicating that an actual touchscreen is @@ -17,4 +18,5 @@ Example: reg = <0x01c25000 0x100>; interrupts = <29>; allwinner,ts-attached; + #thermal-sensor-cells = <0>; }; diff --git a/drivers/input/touchscreen/sun4i-ts.c b/drivers/input/touchscreen/sun4i-ts.c index 28a06749ae42..5851aa0bd78b 100644 --- a/drivers/input/touchscreen/sun4i-ts.c +++ b/drivers/input/touchscreen/sun4i-ts.c @@ -34,6 +34,7 @@ #include #include +#include #include #include #include @@ -107,6 +108,7 @@ struct sun4i_ts_data { struct device *dev; struct input_dev *input; + struct thermal_zone_device *tz; void __iomem *base; unsigned int irq; bool ignore_fifo_data; @@ -180,16 +182,48 @@ static void sun4i_ts_close(struct input_dev *dev) writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); } +static int get_temp(const struct sun4i_ts_data *ts, long *temp) +{ + /* No temp_data until the first irq */ + if (ts->temp_data == -1) + return -EAGAIN; + + /* + * The user manuals do not contain the formula for calculating + * the temperature. The formula used here is from the AXP209, + * which is designed by X-Powers, an affiliate of Allwinner: + * + * temperature = -144.7 + (value * 0.1) + * + * This should be replaced with the correct one if such information + * becomes available. + */ + *temp = (ts->temp_data - 1447) * 100; + + return 0; +} + +static int get_tz_temp(void *data, long *temp) +{ + return get_temp(data, temp); +} + +static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { + .get_temp = get_tz_temp, +}; + static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, char *buf) { struct sun4i_ts_data *ts = dev_get_drvdata(dev); + long temp; + int ret; - /* No temp_data until the first irq */ - if (ts->temp_data == -1) - return -EAGAIN; + ret = get_temp(ts, &temp); + if (ret) + return ret; - return sprintf(buf, "%d\n", (ts->temp_data - 1447) * 100); + return sprintf(buf, "%ld\n", temp); } static ssize_t show_temp_label(struct device *dev, @@ -283,17 +317,27 @@ static int sun4i_ts_probe(struct platform_device *pdev) writel(STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1) | TP_MODE_EN(1), ts->base + TP_CTRL1); + /* + * The thermal core does not register hwmon devices for DT-based + * thermal zone sensors, such as this one. + */ hwmon = devm_hwmon_device_register_with_groups(ts->dev, "sun4i_ts", ts, sun4i_ts_groups); if (IS_ERR(hwmon)) return PTR_ERR(hwmon); + ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts, + &sun4i_ts_tz_ops); + if (IS_ERR(ts->tz)) + ts->tz = NULL; + writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); if (ts_attached) { error = input_register_device(ts->input); if (error) { writel(0, ts->base + TP_INT_FIFOC); + thermal_zone_of_sensor_unregister(ts->dev, ts->tz); return error; } } @@ -310,6 +354,8 @@ static int sun4i_ts_remove(struct platform_device *pdev) if (ts->input) input_unregister_device(ts->input); + thermal_zone_of_sensor_unregister(ts->dev, ts->tz); + /* Deactivate all IRQs */ writel(0, ts->base + TP_INT_FIFOC);