From patchwork Mon Oct 28 07:19:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "(Exiting) Baolin Wang" X-Patchwork-Id: 11214697 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CB6DD1864 for ; Mon, 28 Oct 2019 07:20:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A222321D80 for ; Mon, 28 Oct 2019 07:20:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="v6uDInPr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732641AbfJ1HUL (ORCPT ); Mon, 28 Oct 2019 03:20:11 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:41791 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732605AbfJ1HUK (ORCPT ); Mon, 28 Oct 2019 03:20:10 -0400 Received: by mail-pf1-f196.google.com with SMTP id p26so2148009pfq.8 for ; Mon, 28 Oct 2019 00:20:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :in-reply-to:references; bh=HKtGe92TapQ2KIwqzwkswK8RAIuyaGxBvNdNmUU4dN4=; b=v6uDInPrs2q1qq4SFLLdTjpdDc3eS25cnyOgpZtsm/H1e6dUBVUjCnRTrIW9Je4DLe XqJz6uv+N5YdTtXGCsY5Nwk+YABBQWVqJRGdRpgtWscX0dTeHgTPJbLMsxO2Nn6Hjz3S dbBAmtfdRa2obhR4Db360QfEdyh2kQKCBrXYwvs4DQUeecLSmuAgCNg+8vDcZ+byWbxq kvfNWHa1AXgqxiYlqzAl/rAe0f36GBnVfL8P29Oh6h2SM/31I+Xd91PIcC63SXDmcHIo jZzak31XqYgXmaToPXOP0+62BYK/AyoRWAgahLk4g/uE6jWTpMz8/SETq2QRPAsWDrvB +2AQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:in-reply-to:references; bh=HKtGe92TapQ2KIwqzwkswK8RAIuyaGxBvNdNmUU4dN4=; b=OfgSjXDeppjY9teCFBmzVlg/D7ZeZ89kyXWgUYCw3xXnSBnQG5DiNJHmn4Nc5+OTzH CADKamoG9bhnFVbVyaCIzOSjwEPkUgSJ0S2C/INXKjBh7gGcPmpBu/36LaOpbF0GnH6B rnQPdV68MW0IOVfhEnM+JMmdI+egv/r9Oc0haBks/TatXRggoljctLkZ4WxPko46nOng 8y9E7VNRIcHvFSkW1+U00zX1nIWxy5gBLfoIXWcSM9j+hHgQ1WBJ90//YTpLGTAhA32O LyeiHYRbDTQwYr3alyLHrSQCN8gSxas5crI5Ptl17r+RF1NaJziIJv5R6I2SOVtp9scf EX4w== X-Gm-Message-State: APjAAAUvkEBMD6RRjfwDpz7z3S3GuwkIjn2bT7Heb7uYTBjrSj7jyaA2 R9cHIy5xyl8c4eTUmNi9ln3Ipg== X-Google-Smtp-Source: APXvYqy3mTOff/5UucNGniK8fyS/O+Xgm14NgFfPUR1PrG8IBcUY/kuiLl/NHA1b0kfdyxfyfp644Q== X-Received: by 2002:a62:108:: with SMTP id 8mr9220601pfb.53.1572247209947; Mon, 28 Oct 2019 00:20:09 -0700 (PDT) Received: from baolinwangubtpc.spreadtrum.com ([117.18.48.82]) by smtp.gmail.com with ESMTPSA id 13sm11504703pgq.72.2019.10.28.00.20.06 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 28 Oct 2019 00:20:09 -0700 (PDT) From: Baolin Wang To: sre@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, yuanjiang.yu@unisoc.com, baolin.wang@linaro.org, baolin.wang7@gmail.com, zhang.lyra@gmail.com, orsonzhai@gmail.com Subject: [PATCH 5/5] power: supply: sc27xx: Calibrate the resistance of coulomb counter Date: Mon, 28 Oct 2019 15:19:01 +0800 Message-Id: <9c25e3ab9bdba2914b22cfe7495818740437ef27.1572245011.git.baolin.wang@linaro.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: In-Reply-To: References: Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org There are some deviations between the real resistance and the ideal resistance of coulomb counter, which will affect the accuracy of the coulomb counter, thus calibrate the real resistance of coulomb counter to improve the accuracy. Signed-off-by: Baolin Wang --- drivers/power/supply/sc27xx_fuel_gauge.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c index 221b6fb..f363fa7 100644 --- a/drivers/power/supply/sc27xx_fuel_gauge.c +++ b/drivers/power/supply/sc27xx_fuel_gauge.c @@ -62,6 +62,8 @@ #define SC27XX_FGU_CUR_BASIC_ADC 8192 #define SC27XX_FGU_SAMPLE_HZ 2 +/* micro Ohms */ +#define SC27XX_FGU_IDEAL_RESISTANCE 20000 /* * struct sc27xx_fgu_data: describe the FGU device @@ -84,6 +86,7 @@ * @resist_table_len: the resistance table length * @cur_1000ma_adc: ADC value corresponding to 1000 mA * @vol_1000mv_adc: ADC value corresponding to 1000 mV + * @calib_resist: the real resistance of coulomb counter chip in mOhm * @cap_table: capacity table with corresponding ocv * @resist_table: resistance percent table with corresponding temperature */ @@ -108,6 +111,7 @@ struct sc27xx_fgu_data { int resist_table_len; int cur_1000ma_adc; int vol_1000mv_adc; + int calib_resist; struct power_supply_battery_ocv_table *cap_table; struct power_supply_resistance_temp_table *resist_table; }; @@ -900,7 +904,9 @@ static int sc27xx_fgu_calibration(struct sc27xx_fgu_data *data) */ cal_4200mv = (calib_data & 0x1ff) + 6963 - 4096 - 256; data->vol_1000mv_adc = DIV_ROUND_CLOSEST(cal_4200mv * 10, 42); - data->cur_1000ma_adc = data->vol_1000mv_adc * 4; + data->cur_1000ma_adc = + DIV_ROUND_CLOSEST(data->vol_1000mv_adc * 4 * data->calib_resist, + SC27XX_FGU_IDEAL_RESISTANCE); kfree(buf); return 0; @@ -1079,6 +1085,15 @@ static int sc27xx_fgu_probe(struct platform_device *pdev) return ret; } + ret = device_property_read_u32(&pdev->dev, + "sprd,calib-resistance", + &data->calib_resist); + if (ret) { + dev_err(&pdev->dev, + "failed to get fgu calibration resistance\n"); + return ret; + } + data->channel = devm_iio_channel_get(dev, "bat-temp"); if (IS_ERR(data->channel)) { dev_err(dev, "failed to get IIO channel\n");