From patchwork Tue Dec 6 13:51:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 9462615 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9E3BF60236 for ; Tue, 6 Dec 2016 13:51:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 89DEB283EB for ; Tue, 6 Dec 2016 13:51:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7E6CF283ED; Tue, 6 Dec 2016 13:51:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 03ABB283EC for ; Tue, 6 Dec 2016 13:51:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753266AbcLFNv1 (ORCPT ); Tue, 6 Dec 2016 08:51:27 -0500 Received: from mail-wj0-f182.google.com ([209.85.210.182]:36728 "EHLO mail-wj0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753189AbcLFNv0 (ORCPT ); Tue, 6 Dec 2016 08:51:26 -0500 Received: by mail-wj0-f182.google.com with SMTP id tk12so26681121wjb.3 for ; Tue, 06 Dec 2016 05:51:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=QOMoSj7Oc3mMjesrRI9HXSlGieP2idrRe6zJdgfwP0Q=; b=d5+4zTf7yaSxqBNifSmbAn29k8aXnYCWwrg+PoteoTaTQKCIKVYMvoDGJJi6iXvtrY /D0B/yRY/vzX/sAqschBXHk1+UX0mGly6hTowoGhMC69XmIn9Wd5QyeGiKbpjToIrw4Q avgrdTRcG6vkBulFRtthbwCG/1o0x/yIxGSgk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=QOMoSj7Oc3mMjesrRI9HXSlGieP2idrRe6zJdgfwP0Q=; b=QSQWFryjUTL62uVWJvqY/LFw0wTbgVogUZLoo4qTNxj+50qurjo5Lttjkjj1LO8ixD jepeWaL/uFnQas4hXORwjeMTxaw8CsNqsD+ELvvgrn0jzLbXEvxNggZlgNE/mE/Zyu1b sI2OaqIbvOuu0u8eQ569Ys8BwunzR7SgiEQNzeLicLa7ZHttBkt/ddF88hnO64DNJfbS pB4h3JKZWv+m8aivYh5o+/g1WikDm11VXgqFlbT4QFLvrDn4n1bnHVEiPvavD7OgK0Tr p1tkaENw8j4MG7whxgjC3bofD8adX23c7uJ2GxdPaMY6/guNreMlcRC/9bj5iFjgVrCK NZuw== X-Gm-Message-State: AKaTC01jjd+twKwk88phS5Pl3U2bLojK7BuEjj1Bcr+ZsHiKKvnlgHp6ngXCoNX+WEQGgmzy X-Received: by 10.25.29.8 with SMTP id d8mr19284905lfd.18.1481032283986; Tue, 06 Dec 2016 05:51:23 -0800 (PST) Received: from linuslaptop.ideon.se ([85.235.10.227]) by smtp.gmail.com with ESMTPSA id g38sm3814814lfi.40.2016.12.06.05.51.22 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Dec 2016 05:51:23 -0800 (PST) From: Linus Walleij To: Jonathan Cameron , linux-iio@vger.kernel.org Cc: Linus Walleij , linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, "Ivan T . Ivanov" , Andy Gross , Bjorn Andersson , Stephen Boyd Subject: [PATCH 3/3] iio: adc: add a driver for Qualcomm PM8xxx HK/XOADC Date: Tue, 6 Dec 2016 14:51:19 +0100 Message-Id: <1481032279-27115-1-git-send-email-linus.walleij@linaro.org> X-Mailer: git-send-email 2.7.4 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The Qualcomm PM8xxx PMICs contain a simpler ADC than its successors (already in the kernel as qcom-spmi-adc.c): the HK/XO ADC (Housekeeping/Chrystal oscillator ADC). As far as I can understand this is equal to the PMICs using SSBI transport and encompass PM8018, PM8038, PM8058, PM8917 and PM8921, so this is shortly named PM8xxx. This ADC monitors a bunch of on-board voltages and the die temperature of the PMIC itself, but it can also be routed to convert a few external MPPs (multi-purpose pins). On the APQ8060 DragonBoard this feature is used to let this ADC convert an analog ALS (Ambient Light Sensor) voltage signal from a Capella CM3605 ALS into a LUX value. Developed and tested with APQ8060 DragonBoard based on Ivan's driver. The SPMI VADC driver is quite different, but share enough minor functionality that I have split out to the common file in a previous patch. Cc: linux-arm-kernel@lists.infradead.org Cc: linux-arm-msm@vger.kernel.org Cc: Ivan T. Ivanov Cc: Andy Gross Cc: Bjorn Andersson Cc: Stephen Boyd Signed-off-by: Linus Walleij --- drivers/iio/adc/Kconfig | 10 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/qcom-pm8xxx-xoadc.c | 755 ++++++++++++++++++++++++++++++++++++ 3 files changed, 766 insertions(+) create mode 100644 drivers/iio/adc/qcom-pm8xxx-xoadc.c diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 7edcf3238620..f0b0cbdb9519 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -380,6 +380,16 @@ config PALMAS_GPADC is used in smartphones and tablets and supports a 16 channel general purpose ADC. +config QCOM_PM8XXX_XOADC + tristate "Qualcomm SSBI PM8xxx PMIC XOADCs" + depends on MFD_PM8XXX + help + ADC driver for the XOADC portions of the Qualcomm PM8xxx PMICs + using SSBI transport: PM8018, PM8038, PM8058, PM8917, PM8921. + + To compile this driver as a module, choose M here: the module + will be called qcom-pm8xxx-xoadc. + config QCOM_SPMI_IADC tristate "Qualcomm SPMI PMIC current ADC" depends on SPMI diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index f9468d228b1e..234d45c805f9 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o qcom-vadc-y := qcom-vadc-common.o obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-vadc.o qcom-spmi-vadc.o +obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-vadc.o qcom-pm8xxx-xoadc.o obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o obj-$(CONFIG_STX104) += stx104.o obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o diff --git a/drivers/iio/adc/qcom-pm8xxx-xoadc.c b/drivers/iio/adc/qcom-pm8xxx-xoadc.c new file mode 100644 index 000000000000..a045d260715b --- /dev/null +++ b/drivers/iio/adc/qcom-pm8xxx-xoadc.c @@ -0,0 +1,755 @@ +/* + * Qualcomm PM8xxx PMIC XOADC driver + * + * These ADCs are known as HK/XO (house keeping / chrystal oscillator) + * "XO" in "XOADC" means Chrystal Oscillator. It's a bunch of + * specific-purpose and general purpose ADC converters and channels. + * + * Copyright (C) 2016 Linaro Ltd. + * Author: Linus Walleij + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "qcom-vadc-common.h" + +/* + * Definitions for the "user processor" registers lifted from the v3.4 + * Qualcomm tree. Their kernel has two out-of-tree drivers for the ADC: + * drivers/misc/pmic8058-xoadc.c + * drivers/hwmon/pm8xxx-adc.c + * None of them contain any complete register specification, so this is + * a best effort of combining the information. + */ + +/* These appear to be "battery monitor" registers */ +#define ADC_ARB_BTM_CNTRL1 0x17e +#define ADC_ARB_BTM_CNTRL1_EN_BTM BIT(0) +#define ADC_ARB_BTM_CNTRL1_SEL_OP_MODE BIT(1) +#define ADC_ARB_BTM_CNTRL1_MEAS_INTERVAL1 BIT(2) +#define ADC_ARB_BTM_CNTRL1_MEAS_INTERVAL2 BIT(3) +#define ADC_ARB_BTM_CNTRL1_MEAS_INTERVAL3 BIT(4) +#define ADC_ARB_BTM_CNTRL1_MEAS_INTERVAL4 BIT(5) +#define ADC_ARB_BTM_CNTRL1_EOC BIT(6) +#define ADC_ARB_BTM_CNTRL1_REQ BIT(7) + +#define ADC_ARB_BTM_AMUX_CNTRL 0x17f +#define ADC_ARB_BTM_ANA_PARAM 0x180 +#define ADC_ARB_BTM_DIG_PARAM 0x181 +#define ADC_ARB_BTM_RSV 0x182 +#define ADC_ARB_BTM_DATA1 0x183 +#define ADC_ARB_BTM_DATA0 0x184 +#define ADC_ARB_BTM_BAT_COOL_THR1 0x185 +#define ADC_ARB_BTM_BAT_COOL_THR0 0x186 +#define ADC_ARB_BTM_BAT_WARM_THR1 0x187 +#define ADC_ARB_BTM_BAT_WARM_THR0 0x188 +#define ADC_ARB_BTM_CNTRL2 0x18c + +/* Proper ADC registers */ + +#define ADC_ARB_USRP_CNTRL 0x197 +#define ADC_ARB_USRP_CNTRL_EN_ARB BIT(0) +#define ADC_ARB_USRP_CNTRL_RSV1 BIT(1) +#define ADC_ARB_USRP_CNTRL_RSV2 BIT(2) +#define ADC_ARB_USRP_CNTRL_RSV3 BIT(3) +#define ADC_ARB_USRP_CNTRL_RSV4 BIT(4) +#define ADC_ARB_USRP_CNTRL_RSV5 BIT(5) +#define ADC_ARB_USRP_CNTRL_EOC BIT(6) +#define ADC_ARB_USRP_CNTRL_REQ BIT(7) + +#define ADC_ARB_USRP_AMUX_CNTRL 0x198 +#define ADC_ARB_USRP_AMUX_CNTRL_RSV0 BIT(0) +#define ADC_ARB_USRP_AMUX_CNTRL_RSV1 BIT(1) +#define ADC_ARB_USRP_AMUX_CNTRL_PREMUX0 BIT(2) +#define ADC_ARB_USRP_AMUX_CNTRL_PREMUX1 BIT(3) +#define ADC_ARB_USRP_AMUX_CNTRL_SEL0 BIT(4) +#define ADC_ARB_USRP_AMUX_CNTRL_SEL1 BIT(5) +#define ADC_ARB_USRP_AMUX_CNTRL_SEL2 BIT(6) +#define ADC_ARB_USRP_AMUX_CNTRL_SEL3 BIT(7) +#define ADC_AMUX_PREMUX_SHIFT 2 +#define ADC_AMUX_SEL_SHIFT 4 + +/* We know very little about the bits in this register */ +#define ADC_ARB_USRP_ANA_PARAM 0x199 +#define ADC_ARB_USRP_ANA_PARAM_DIS 0xFE +#define ADC_ARB_USRP_ANA_PARAM_EN 0xFF + +#define ADC_ARB_USRP_DIG_PARAM 0x19A +#define ADC_ARB_USRP_DIG_PARAM_SEL_SHIFT0 BIT(0) +#define ADC_ARB_USRP_DIG_PARAM_SEL_SHIFT1 BIT(1) +#define ADC_ARB_USRP_DIG_PARAM_CLK_RATE0 BIT(2) +#define ADC_ARB_USRP_DIG_PARAM_CLK_RATE1 BIT(3) +#define ADC_ARB_USRP_DIG_PARAM_EOC BIT(4) +/* + * On a later ADC the decimation factors are defined as + * 00 = 512, 01 = 1024, 10 = 2048, 11 = 4096 so assume this + * holds also for this older XOADC. + */ +#define ADC_ARB_USRP_DIG_PARAM_DEC_RATE0 BIT(5) +#define ADC_ARB_USRP_DIG_PARAM_DEC_RATE1 BIT(6) +#define ADC_ARB_USRP_DIG_PARAM_EN BIT(7) +#define ADC_DIG_PARAM_DEC_SHIFT 5 + +#define ADC_ARB_USRP_RSV 0x19B +#define ADC_ARB_USRP_RSV_RST BIT(0) +#define ADC_ARB_USRP_RSV_DTEST0 BIT(1) +#define ADC_ARB_USRP_RSV_DTEST1 BIT(2) +#define ADC_ARB_USRP_RSV_OP BIT(3) +#define ADC_ARB_USRP_RSV_IP_SEL0 BIT(4) +#define ADC_ARB_USRP_RSV_IP_SEL1 BIT(5) +#define ADC_ARB_USRP_RSV_IP_SEL2 BIT(6) +#define ADC_ARB_USRP_RSV_TRM BIT(7) +#define ADC_RSV_IP_SEL_SHIFT 4 + +#define ADC_ARB_USRP_DATA0 0x19D +#define ADC_ARB_USRP_DATA1 0x19C + +/* Physical channels. MPP = Multi-Purpose Pin */ +#define CHANNEL_VCOIN 0x0 /* Coincell */ +#define CHANNEL_VBAT 0x1 /* Battery voltage */ +#define CHANNEL_VCHG 0x2 /* Charger voltage */ +#define CHANNEL_CHG_MONITOR 0x3 /* Charger current monitor */ +#define CHANNEL_VPH_PWR 0x4 /* Main system power VPH */ +#define CHANNEL_MPP5 0x5 /* "Battery charge current" */ +#define CHANNEL_MPP6 0x6 /* "MPP1" */ +#define CHANNEL_MPP7 0x7 /* "MPP2" */ +#define CHANNEL_MPP8 0x8 /* Battery temperature */ +#define CHANNEL_MPP9 0x9 /* Battery detection */ +#define CHANNEL_USB_VBUS 0xa /* USB charger voltage */ +#define CHANNEL_DIE_TEMP 0xb /* PMIC die temperature */ +#define CHANNEL_INTERNAL 0xc /* 625mV reference channel */ +#define CHANNEL_125V 0xd /* 1.25V reference channel */ +#define CHANNEL_INTERNAL_2 0xe /* Charger temperature */ +#define CHANNEL_MUXOFF 0xf /* Channel to reduce input load on mux */ + +#define XOADC_CHAN_MAX 15 /* 4 bits */ + +/* MPP = Multi-Purpose Pins */ +#define PREMUX_MPP_SCALE_0 0x0 /* No scaling on the signal */ +#define PREMUX_MPP_SCALE_1 0x1 /* Unity scaling selected by the user */ +#define PREMUX_MPP_SCALE_1_DIV3 0x2 /* 1/3 prescaler on the input from MPP */ + +/* Defines reference voltage for the XOADC */ +#define AMUX_RSV0 0x0 /* XO_IN/XOADC_GND */ +#define AMUX_RSV1 0x1 /* PMIC_IN/XOADC_GND */ +#define AMUX_RSV2 0x2 /* PMIC_IN/BMS_CSP */ +#define AMUX_RSV3 0x3 /* not used */ +#define AMUX_RSV4 0x4 /* XOADC_GND/XOADC_GND */ +#define AMUX_RSV5 0x5 /* XOADC_VREF/XOADC_GND */ +#define XOADC_RSV_MAX 5 /* 3 bits 0..7, 3 and 6,7 are invalid */ + +/* + * The different channels have hard-coded prescale ratios defined + * by the hardware. + */ +static const struct vadc_prescale_ratio adc_prescale_ratios[] = { + { .num = 1, .den = 2 }, /* CHANNEL_VCOIN */ + { .num = 1, .den = 3 }, /* CHANNEL_VBAT */ + { .num = 1, .den = 10 }, /* CHANNEL_VCHG */ + { .num = 1, .den = 1 }, /* CHANNEL_CHG_MONITOR */ + { .num = 1, .den = 3 }, /* CHANNEL_VPH_PWR */ + { .num = 1, .den = 1 }, /* CHANNEL_MPP5 */ + { .num = 1, .den = 1 }, /* CHANNEL_MPP6 */ + { .num = 1, .den = 2 }, /* CHANNEL_MPP7 */ + { .num = 1, .den = 2 }, /* CHANNEL_MPP8 */ + { .num = 1, .den = 3 }, /* CHANNEL_MPP9 */ + { .num = 1, .den = 3 }, /* CHANNEL_USB_VBUS */ + { .num = 1, .den = 1 }, /* CHANNEL_DIE_TEMP */ + { .num = 1, .den = 1 }, /* CHANNEL_INTERNAL */ + { .num = 1, .den = 1 }, /* CHANNEL_125V */ + { .num = 1, .den = 1 }, /* CHANNEL_INTERNAL_2 */ + { .num = 1, .den = 1 }, /* CHANNEL_MUXOFF */ +}; + +/** + * struct pm8xxx_chan_info - ADC channel information + * @name: name of this channel + * @calibration: whether to use absolute or ratiometric calibration + * @amux_channel: channel 0..15 + * @decimation: 0,1,2,3 + * @amux_mpp_channel: MPP channel 0..3 + * @amux_ip_rsv: ratiometric scale value if using ratiometric + * calibration: 0, 1, 2, 4, 5. + */ +struct pm8xxx_chan_info { + const char *name; + enum vadc_calibration calibration; + u8 amux_channel:4; + u8 decimation:2; + u8 amux_mpp_channel:2; + u8 amux_ip_rsv:3; +}; + +/** + * struct pm8xxx_xoadc - state container for the XOADC + * @dev: pointer to device + * @map: regmap to access registers + * @vref: reference voltage regulator + * @nchans: number of channels + * @chans: the channel information per-channel + * @iio_chans: IIO channel specifiers + * @graph: linear calibration parameters for absolute and + * ratiometric measurements + * @complete: completion to indicate end of conversion + */ +struct pm8xxx_xoadc { + struct device *dev; + struct regmap *map; + struct regulator *vref; + unsigned int nchans; + struct pm8xxx_chan_info *chans; + struct iio_chan_spec *iio_chans; + struct vadc_linear_graph graph[2]; + struct completion complete; +}; + +static irqreturn_t pm8xxx_eoc_irq(int irq, void *d) +{ + struct iio_dev *indio_dev = d; + struct pm8xxx_xoadc *adc = iio_priv(indio_dev); + + complete(&adc->complete); + + return IRQ_HANDLED; +} + +static struct pm8xxx_chan_info * +pm8xxx_get_channel(struct pm8xxx_xoadc *adc, u8 chan) +{ + struct pm8xxx_chan_info *ch; + int i; + + if (chan >= adc->nchans) + return NULL; + + for (i = 0; i < adc->nchans; i++) { + ch = &adc->chans[i]; + if (ch->amux_channel == chan) + break; + } + if (i == adc->nchans) + return NULL; + + return ch; +} + +static int pm8xxx_read_channel_rsv(struct pm8xxx_xoadc *adc, + const struct pm8xxx_chan_info *ch, + u8 rsv, u16 *adc_code) +{ + int ret; + unsigned int val; + u8 rsvmask, rsvval; + u8 lsb, msb; + + dev_dbg(adc->dev, "read channel \"%s\", amux %d, mpp %d, rsv %d\n", + ch->name, ch->amux_channel, ch->amux_mpp_channel, rsv); + + /* Mux in this channel */ + ret = regmap_write(adc->map, ADC_ARB_USRP_AMUX_CNTRL, + ch->amux_channel << ADC_AMUX_SEL_SHIFT | + ch->amux_mpp_channel << ADC_AMUX_PREMUX_SHIFT); + if (ret) + return ret; + + /* Set up ratiometric scale value */ + rsvmask = (ADC_ARB_USRP_RSV_RST | ADC_ARB_USRP_RSV_DTEST0 | + ADC_ARB_USRP_RSV_DTEST1 | ADC_ARB_USRP_RSV_OP); + if (ch->calibration == VADC_CALIB_RATIOMETRIC) { + if (rsv == 0xff) + rsvval = (ch->amux_ip_rsv << ADC_RSV_IP_SEL_SHIFT) | + ADC_ARB_USRP_RSV_TRM; + else + rsvval = (rsv << ADC_RSV_IP_SEL_SHIFT) | + ADC_ARB_USRP_RSV_TRM; + } else { + /* We are not ratiometric so turn this off */ + rsvval = ADC_ARB_USRP_RSV_IP_SEL1; + } + + ret = regmap_update_bits(adc->map, + ADC_ARB_USRP_RSV, + ~rsvmask, + rsvval); + if (ret) + return ret; + + ret = regmap_write(adc->map, ADC_ARB_USRP_ANA_PARAM, + ADC_ARB_USRP_ANA_PARAM_DIS); + if (ret) + return ret; + + /* Decimation factor */ + ret = regmap_write(adc->map, ADC_ARB_USRP_DIG_PARAM, + ADC_ARB_USRP_DIG_PARAM_SEL_SHIFT0 | + ADC_ARB_USRP_DIG_PARAM_SEL_SHIFT1 | + ch->decimation << ADC_DIG_PARAM_DEC_SHIFT); + if (ret) + return ret; + + ret = regmap_write(adc->map, ADC_ARB_USRP_ANA_PARAM, + ADC_ARB_USRP_ANA_PARAM_EN); + if (ret) + return ret; + + /* Enable the arbiter, the Qualcomm code does it twice like this */ + ret = regmap_write(adc->map, ADC_ARB_USRP_CNTRL, + ADC_ARB_USRP_CNTRL_EN_ARB); + if (ret) + return ret; + ret = regmap_write(adc->map, ADC_ARB_USRP_CNTRL, + ADC_ARB_USRP_CNTRL_EN_ARB); + if (ret) + return ret; + + + /* Fire a request! */ + reinit_completion(&adc->complete); + ret = regmap_write(adc->map, ADC_ARB_USRP_CNTRL, + ADC_ARB_USRP_CNTRL_EN_ARB | + ADC_ARB_USRP_CNTRL_REQ); + if (ret) + return ret; + + /* Next the interrupt occurs */ + ret = wait_for_completion_timeout(&adc->complete, + VADC_CONV_TIME_MAX_US); + if (!ret) { + dev_err(adc->dev, "conversion timed out\n"); + return -ETIMEDOUT; + } + + ret = regmap_read(adc->map, ADC_ARB_USRP_DATA0, &val); + if (ret) + return ret; + lsb = val; + ret = regmap_read(adc->map, ADC_ARB_USRP_DATA1, &val); + if (ret) + return ret; + msb = val; + *adc_code = (msb << 8) | lsb; + + /* Turn off the ADC by setting the arbiter to 0 twice */ + ret = regmap_write(adc->map, ADC_ARB_USRP_CNTRL, 0); + if (ret) + return ret; + ret = regmap_write(adc->map, ADC_ARB_USRP_CNTRL, 0); + if (ret) + return ret; + + return 0; +} + +static int pm8xxx_read_channel(struct pm8xxx_xoadc *adc, + const struct pm8xxx_chan_info *ch, + u16 *adc_code) +{ + /* + * Normally we just use the ratiometric scale value (RSV) predefined + * for the channel, but during calibration we need to modify this + * so this wrapper is a helper hiding the more complex version. + */ + return pm8xxx_read_channel_rsv(adc, ch, 0xff, adc_code); +} + +static s32 pm8xxx_calibrate(struct pm8xxx_xoadc *adc, + const struct pm8xxx_chan_info *ch, + u16 adc_code) +{ + return qcom_vadc_calibrate(&adc_prescale_ratios[ch->amux_channel], + &adc->graph[ch->calibration], + (ch->calibration == VADC_CALIB_ABSOLUTE), + adc_code); +} + +static int pm8xxx_calibrate_device(struct pm8xxx_xoadc *adc) +{ + const struct pm8xxx_chan_info *ch; + u16 read_1250v; + u16 read_0625v; + u16 read_nomux_rsv5; + u16 read_nomux_rsv4; + int ret; + + + adc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV; + adc->graph[VADC_CALIB_RATIOMETRIC].dx = VADC_RATIOMETRIC_RANGE_UV; + + /* Common reference channel calibration */ + ch = pm8xxx_get_channel(adc, CHANNEL_125V); + if (!ch) + return -ENODEV; + ret = pm8xxx_read_channel(adc, ch, &read_1250v); + if (ret) { + dev_err(adc->dev, "could not read 1.25V reference channel\n"); + return -ENODEV; + } + ch = pm8xxx_get_channel(adc, CHANNEL_INTERNAL); + if (!ch) + return -ENODEV; + ret = pm8xxx_read_channel(adc, ch, &read_0625v); + if (ret) { + dev_err(adc->dev, "could not read 0.625V reference channel\n"); + return -ENODEV; + } + if (read_1250v == read_0625v) { + dev_err(adc->dev, "read same ADC code for 1.25V and 0.625V\n"); + return -ENODEV; + } + + adc->graph[VADC_CALIB_ABSOLUTE].dy = read_1250v - read_0625v; + adc->graph[VADC_CALIB_ABSOLUTE].gnd = read_0625v; + + dev_info(adc->dev, "absolute calibration dx = %d uV, dy = %d units\n", + VADC_ABSOLUTE_RANGE_UV, adc->graph[VADC_CALIB_ABSOLUTE].dy); + + /* Ratiometric calibration */ + ch = pm8xxx_get_channel(adc, CHANNEL_MUXOFF); + if (!ch) + return -ENODEV; + ret = pm8xxx_read_channel_rsv(adc, ch, AMUX_RSV5, &read_nomux_rsv5); + if (ret) { + dev_err(adc->dev, "could not read MUXOFF reference channel\n"); + return -ENODEV; + } + ret = pm8xxx_read_channel_rsv(adc, ch, AMUX_RSV4, &read_nomux_rsv4); + if (ret) { + dev_err(adc->dev, "could not read MUXOFF reference channel\n"); + return -ENODEV; + } + adc->graph[VADC_CALIB_RATIOMETRIC].dy = + read_nomux_rsv5 - read_nomux_rsv4; + adc->graph[VADC_CALIB_RATIOMETRIC].gnd = read_nomux_rsv4; + + dev_info(adc->dev, "ratiometric calibration dx = %d uV, dy = %d units\n", + VADC_RATIOMETRIC_RANGE_UV, + adc->graph[VADC_CALIB_RATIOMETRIC].dy); + + return 0; +} + +static int pm8xxx_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct pm8xxx_xoadc *adc = iio_priv(indio_dev); + const struct pm8xxx_chan_info *ch; + u16 adc_code; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + /* Only die temperature ends up here */ + ch = pm8xxx_get_channel(adc, chan->address); + if (!ch) { + dev_err(adc->dev, "no such channel %lu\n", + chan->address); + return -EINVAL; + } + ret = pm8xxx_read_channel(adc, ch, &adc_code); + if (ret) + return ret; + *val = pm8xxx_calibrate(adc, ch, adc_code); + /* 2mV/K, return milli Celsius */ + *val /= 2; + *val -= KELVINMIL_CELSIUSMIL; + return IIO_VAL_INT; + case IIO_CHAN_INFO_RAW: + switch (chan->type) { + case IIO_VOLTAGE: + ch = pm8xxx_get_channel(adc, chan->address); + if (!ch) { + dev_err(adc->dev, "no such channel %lu\n", + chan->address); + return -EINVAL; + } + ret = pm8xxx_read_channel(adc, ch, &adc_code); + if (ret) + return ret; + *val = pm8xxx_calibrate(adc, ch, adc_code); + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SCALE: + /* + * Applies to all voltage channels: we scale the microvolts + * to millivolts as required by the userspace ABI. + */ + *val = 0; + *val2 = 1000; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static const struct iio_info pm8xxx_xoadc_info = { + .driver_module = THIS_MODULE, + .read_raw = pm8xxx_read_raw, +}; + +static int pm8xxx_xoadc_parse_channel(struct device *dev, + struct device_node *np, + struct pm8xxx_chan_info *ch) +{ + const char *name = np->name; + u32 chan, rsv, dec; + int ret; + + ret = of_property_read_u32(np, "reg", &chan); + if (ret) { + dev_err(dev, "invalid channel number %s\n", name); + return ret; + } + if (chan > XOADC_CHAN_MAX) { + dev_err(dev, "%s too big channel number %d\n", name, chan); + return -EINVAL; + } + + if (of_property_read_bool(np, "qcom,ratiometric")) { + ch->calibration = VADC_CALIB_RATIOMETRIC; + ret = of_property_read_u32(np, "qcom,ratiometric-ref", &rsv); + if (ret) { + dev_err(dev, "invalid RSV %s\n", name); + return ret; + } + if (rsv > XOADC_RSV_MAX) { + dev_err(dev, "%s too large RSV value %d\n", name, rsv); + return -EINVAL; + } + if (rsv == AMUX_RSV3) { + dev_err(dev, "%s invalid RSV value %d\n", name, rsv); + return -EINVAL; + } + } else { + ch->calibration = VADC_CALIB_ABSOLUTE; + rsv = 0; + } + + ret = of_property_read_u32(np, "qcom,decimation", &dec); + if (!ret) { + /* It's OK to skip this ... */ + ret = qcom_vadc_decimation_from_dt(dec); + if (ret < 0) { + dev_err(dev, "%s invalid decimation %d\n", + name, dec); + return ret; + } + ch->decimation = ret; + } else { + ch->decimation = VADC_DEF_DECIMATION; + } + + ch->amux_channel = chan; + ch->name = name; + ch->amux_ip_rsv = rsv; + ch->amux_mpp_channel = PREMUX_MPP_SCALE_0; /* FIXME: get from DT */ + + dev_dbg(dev, "channel %d \"%s\" ref voltage: %d, decimation %d\n", + ch->amux_channel, + ch->name, + ch->amux_ip_rsv, + ch->decimation); + return 0; +} + +static int pm8xxx_xoadc_parse_channels(struct pm8xxx_xoadc *adc, + struct device_node *np) +{ + struct device_node *child; + struct pm8xxx_chan_info *ch; + int ret; + int i; + + adc->nchans = of_get_available_child_count(np); + if (!adc->nchans) { + dev_err(adc->dev, "no channel children\n"); + return -ENODEV; + } + dev_dbg(adc->dev, "found %d ADC channels\n", adc->nchans); + + adc->iio_chans = devm_kcalloc(adc->dev, adc->nchans, + sizeof(*adc->iio_chans), GFP_KERNEL); + if (!adc->iio_chans) + return -ENOMEM; + + adc->chans = devm_kcalloc(adc->dev, adc->nchans, + sizeof(*adc->chans), GFP_KERNEL); + if (!adc->chans) + return -ENOMEM; + + i = 0; + for_each_available_child_of_node(np, child) { + struct iio_chan_spec *iio_chan; + + ch = &adc->chans[i]; + ret = pm8xxx_xoadc_parse_channel(adc->dev, child, ch); + if (ret) { + of_node_put(child); + return ret; + } + + iio_chan = &adc->iio_chans[i]; + iio_chan->channel = ch->amux_channel; + iio_chan->datasheet_name = ch->name; + /* A single temperature channel, the rest are voltages */ + if (ch->amux_channel == CHANNEL_DIE_TEMP) { + iio_chan->type = IIO_TEMP; + iio_chan->info_mask_separate = + BIT(IIO_CHAN_INFO_PROCESSED); + } else { + iio_chan->type = IIO_VOLTAGE; + iio_chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE); + } + iio_chan->indexed = 1; + iio_chan->address = ch->amux_channel; + + i++; + } + + /* Check for required channels */ + ch = pm8xxx_get_channel(adc, CHANNEL_125V); + if (!ch) { + dev_err(adc->dev, "missing 1.25V reference channel\n"); + return -ENODEV; + } + ch = pm8xxx_get_channel(adc, CHANNEL_INTERNAL); + if (!ch) { + dev_err(adc->dev, "missing 0.625V reference channel\n"); + return -ENODEV; + } + ch = pm8xxx_get_channel(adc, CHANNEL_MUXOFF); + if (!ch) { + dev_err(adc->dev, "missing MUXOFF reference channel\n"); + return -ENODEV; + } + + return 0; +} + +static int pm8xxx_xoadc_probe(struct platform_device *pdev) +{ + struct pm8xxx_xoadc *adc; + struct iio_dev *indio_dev; + struct device_node *np = pdev->dev.of_node; + struct regmap *map; + struct device *dev = &pdev->dev; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*adc)); + if (!indio_dev) + return -ENOMEM; + platform_set_drvdata(pdev, indio_dev); + + adc = iio_priv(indio_dev); + adc->dev = dev; + init_completion(&adc->complete); + + ret = pm8xxx_xoadc_parse_channels(adc, np); + if (ret) + return ret; + + map = dev_get_regmap(dev->parent, NULL); + if (!map) { + dev_err(dev, "Parent regmap unavailable.\n"); + return -ENXIO; + } + adc->map = map; + + /* Bring up regulator */ + adc->vref = devm_regulator_get(dev, "xoadc-ref"); + if (IS_ERR(adc->vref)) { + dev_err(dev, "failed to get XOADC VREF regulator\n"); + return PTR_ERR(adc->vref); + } + /* We strictly require this voltage */ + ret = regulator_set_voltage(adc->vref, 2200000, 2200000); + if (ret) { + dev_err(dev, "unable to set LDO18 voltage to 2.2V\n"); + return ret; + } + ret = regulator_enable(adc->vref); + if (ret) { + dev_err(dev, "failed to enable XOADC VREF regulator\n"); + return ret; + } + + ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0), + pm8xxx_eoc_irq, NULL, 0, "pm8xxx-adc", indio_dev); + if (ret) { + dev_err(dev, "unable to request IRQ\n"); + goto out_disable_vref; + } + + indio_dev->dev.parent = dev; + indio_dev->dev.of_node = np; + indio_dev->name = "pm8xxx-xoadc"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &pm8xxx_xoadc_info; + indio_dev->channels = adc->iio_chans; + indio_dev->num_channels = adc->nchans; + + ret = iio_device_register(indio_dev); + if (ret) + goto out_disable_vref; + + ret = pm8xxx_calibrate_device(adc); + if (ret) + goto out_unreg_device; + + dev_info(dev, "PM8xxx XOADC driver enabled\n"); + + return 0; + +out_unreg_device: + iio_device_unregister(indio_dev); +out_disable_vref: + regulator_disable(adc->vref); + + return ret; +} + +static int pm8xxx_xoadc_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + struct pm8xxx_xoadc *adc = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + regulator_disable(adc->vref); + + return 0; +} + +static const struct of_device_id pm8xxx_xoadc_id_table[] = { + { + .compatible = "qcom,pm8058-adc", + }, + { }, +}; +MODULE_DEVICE_TABLE(of, pm8xxx_xoadc_id_table); + +static struct platform_driver pm8xxx_xoadc_driver = { + .driver = { + .name = "pm8xxx-adc", + .of_match_table = pm8xxx_xoadc_id_table, + }, + .probe = pm8xxx_xoadc_probe, + .remove = pm8xxx_xoadc_remove, +}; +module_platform_driver(pm8xxx_xoadc_driver); + +MODULE_DESCRIPTION("PM8xxx XOADC driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:pm8xxx-xoadc");