From patchwork Mon Jul 19 08:58:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prabhakar X-Patchwork-Id: 12385049 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AF13C12002 for ; Mon, 19 Jul 2021 08:59:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54F0A613F2 for ; Mon, 19 Jul 2021 08:59:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235469AbhGSISV (ORCPT ); Mon, 19 Jul 2021 04:18:21 -0400 Received: from relmlor1.renesas.com ([210.160.252.171]:14960 "EHLO relmlie5.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S235466AbhGSISR (ORCPT ); Mon, 19 Jul 2021 04:18:17 -0400 X-IronPort-AV: E=Sophos;i="5.84,251,1620658800"; d="scan'208";a="88109146" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 19 Jul 2021 17:58:56 +0900 Received: from localhost.localdomain (unknown [10.226.36.204]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id 2273F400A0FB; Mon, 19 Jul 2021 17:58:52 +0900 (JST) From: Lad Prabhakar To: Geert Uytterhoeven , Rob Herring , Jonathan Cameron , Lars-Peter Clausen , Michael Turquette , Magnus Damm , Stephen Boyd , Philipp Zabel , Alexandru Ardelean Cc: linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Prabhakar , Biju Das , Lad Prabhakar Subject: [PATCH v2 2/4] iio: adc: Add driver for Renesas RZ/G2L A/D converter Date: Mon, 19 Jul 2021 09:58:38 +0100 Message-Id: <20210719085840.21842-3-prabhakar.mahadev-lad.rj@bp.renesas.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210719085840.21842-1-prabhakar.mahadev-lad.rj@bp.renesas.com> References: <20210719085840.21842-1-prabhakar.mahadev-lad.rj@bp.renesas.com> Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Add ADC driver support for Renesas RZ/G2L A/D converter in SW trigger mode. A/D Converter block is a successive approximation analog-to-digital converter with a 12-bit accuracy and supports a maximum of 8 input channels. Signed-off-by: Lad Prabhakar Reviewed-by: Biju Das --- MAINTAINERS | 8 + drivers/iio/adc/Kconfig | 10 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/rzg2l_adc.c | 545 ++++++++++++++++++++++++++++++++++++ 4 files changed, 564 insertions(+) create mode 100644 drivers/iio/adc/rzg2l_adc.c diff --git a/MAINTAINERS b/MAINTAINERS index 6c8be735cc91..6a52f9f4604c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15839,6 +15839,14 @@ L: linux-renesas-soc@vger.kernel.org S: Maintained F: drivers/phy/renesas/phy-rcar-gen3-usb*.c +RENESAS RZ/G2L A/D DRIVER +M: Lad Prabhakar +L: linux-iio@vger.kernel.org +L: linux-renesas-soc@vger.kernel.org +S: Supported +F: Documentation/devicetree/bindings/iio/adc/renesas,rzg2l-adc.yaml +F: drivers/iio/adc/rzg2l_adc.c + RESET CONTROLLER FRAMEWORK M: Philipp Zabel S: Maintained diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index db0c8fb60515..af168e1c9fdb 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -887,6 +887,16 @@ config ROCKCHIP_SARADC To compile this driver as a module, choose M here: the module will be called rockchip_saradc. +config RZG2L_ADC + tristate "Renesas RZ/G2L ADC driver" + depends on ARCH_R9A07G044 || COMPILE_TEST + help + Say yes here to build support for the ADC found in Renesas + RZ/G2L family. + + To compile this driver as a module, choose M here: the + module will be called rzg2l_adc. + config SC27XX_ADC tristate "Spreadtrum SC27xx series PMICs ADC" depends on MFD_SC27XX_PMIC || COMPILE_TEST diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index f70d877c555a..d68550f493e3 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -82,6 +82,7 @@ obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-pm8xxx-xoadc.o obj-$(CONFIG_RCAR_GYRO_ADC) += rcar-gyroadc.o obj-$(CONFIG_RN5T618_ADC) += rn5t618-adc.o obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o +obj-$(CONFIG_RZG2L_ADC) += rzg2l_adc.o obj-$(CONFIG_SC27XX_ADC) += sc27xx_adc.o obj-$(CONFIG_SPEAR_ADC) += spear_adc.o obj-$(CONFIG_STX104) += stx104.o diff --git a/drivers/iio/adc/rzg2l_adc.c b/drivers/iio/adc/rzg2l_adc.c new file mode 100644 index 000000000000..033cdec9e976 --- /dev/null +++ b/drivers/iio/adc/rzg2l_adc.c @@ -0,0 +1,545 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RZ/G2L A/D Converter driver + * + * Copyright (c) 2021 Renesas Electronics Europe GmbH + * + * Author: Lad Prabhakar + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_NAME "rzg2l-adc" + +#define RZG2L_ADM(n) ((n) * 0x4) +#define RZG2L_ADM0_ADCE BIT(0) +#define RZG2L_ADM0_ADBSY BIT(1) +#define RZG2L_ADM0_PWDWNB BIT(2) +#define RZG2L_ADM0_SRESB BIT(15) +#define RZG2L_ADM1_TRG BIT(0) +#define RZG2L_ADM1_MS BIT(2) +#define RZG2L_ADM1_BS BIT(4) +#define RZG2L_ADM1_EGA_CLEAR ~GENMASK(13, 12) +#define RZG2L_ADM2_CHSEL_CLEAR ~GENMASK(7, 0) +#define RZG2L_ADM3_ADSMP 0x578 +#define RZG2L_ADM3_ADCMP (0xe << 16) +#define RZG2L_ADM3_ADIL_CLEAR ~GENMASK(31, 24) + +#define RZG2L_ADINT 0x20 +#define RZG2L_ADINT_CH_CLEAR ~GENMASK(7, 0) +#define RZG2L_ADINT_CSEEN BIT(16) +#define RZG2L_ADINT_INTS BIT(31) +#define RZG2L_ADSTS 0x24 +#define RZG2L_ADINT_INTST_MASK GENMASK(7, 0) +#define RZG2L_ADSTS_CSEST BIT(16) +#define RZG2L_ADIVC 0x28 +#define RZG2L_ADIVC_DIVADC_CLEAR ~GENMASK(8, 0) +#define RZG2L_ADIVC_DIVADC_4 0x4 +#define RZG2L_ADFIL 0x2c +#define RZG2L_ADCR(n) (0x30 + ((n) * 0x4)) +#define RZG2L_ADCR_AD_MASK GENMASK(11, 0) + +#define RZG2L_ADC_MAX_CHANNELS 8 +#define RZG2L_ADC_CHN_MASK 0x7 +#define RZG2L_ADC_TIMEOUT usecs_to_jiffies(1 * 4) + +struct rzg2l_adc_data { + const struct iio_chan_spec *channels; + u8 num_channels; +}; + +struct rzg2l_adc { + void __iomem *base; + struct clk *pclk; + struct clk *adclk; + struct reset_control *presetn; + struct reset_control *adrstn; + struct completion completion; + const struct rzg2l_adc_data *data; + u16 last_val[RZG2L_ADC_MAX_CHANNELS]; +}; + +static const char * const rzg2l_adc_channel_name[] = { + "adc0", + "adc1", + "adc2", + "adc3", + "adc4", + "adc5", + "adc6", + "adc7", +}; + +static unsigned int rzg2l_adc_readl(struct rzg2l_adc *adc, u32 reg) +{ + return readl(adc->base + reg); +} + +static void rzg2l_adc_writel(struct rzg2l_adc *adc, unsigned int reg, u32 val) +{ + writel(val, adc->base + reg); +} + +static void rzg2l_adc_pwr(struct rzg2l_adc *adc, bool on) +{ + u32 reg; + + reg = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + if (on) + reg |= RZG2L_ADM0_PWDWNB; + else + reg &= ~RZG2L_ADM0_PWDWNB; + rzg2l_adc_writel(adc, RZG2L_ADM(0), reg); + udelay(2); +} + +static void rzg2l_adc_start_stop(struct rzg2l_adc *adc, bool start) +{ + int timeout = 5; + u32 reg; + + /* stop A/D conversion */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + if (start) + reg |= RZG2L_ADM0_ADCE; + else + reg &= ~RZG2L_ADM0_ADCE; + rzg2l_adc_writel(adc, RZG2L_ADM(0), reg); + + if (start) + return; + + do { + usleep_range(100, 200); + reg = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + timeout--; + if (!timeout) { + pr_err("%s stopping ADC timed out\n", __func__); + break; + } + } while (((reg & RZG2L_ADM0_ADBSY) || (reg & RZG2L_ADM0_ADCE))); +} + +static void rzg2l_set_trigger(struct rzg2l_adc *adc) +{ + u32 reg; + + /* SW trigger */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(1)); + reg &= RZG2L_ADM1_EGA_CLEAR; + reg &= ~RZG2L_ADM1_BS; + reg |= RZG2L_ADM1_MS; + reg &= ~RZG2L_ADM1_TRG; + rzg2l_adc_writel(adc, RZG2L_ADM(1), reg); +} + +static int rzg2l_adc_conversion_setup(struct rzg2l_adc *adc, u8 ch) +{ + u32 reg; + + if (rzg2l_adc_readl(adc, RZG2L_ADM(0)) & RZG2L_ADM0_ADBSY) + return -EBUSY; + + rzg2l_set_trigger(adc); + + /* select channel */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(2)); + reg &= RZG2L_ADM2_CHSEL_CLEAR; + reg |= BIT(ch); + rzg2l_adc_writel(adc, RZG2L_ADM(2), reg); + + reg = rzg2l_adc_readl(adc, RZG2L_ADM(3)); + reg &= RZG2L_ADM3_ADIL_CLEAR; + reg |= RZG2L_ADM3_ADCMP; + reg |= RZG2L_ADM3_ADSMP; + rzg2l_adc_writel(adc, RZG2L_ADM(3), reg); + + reg = rzg2l_adc_readl(adc, RZG2L_ADIVC); + reg &= RZG2L_ADIVC_DIVADC_CLEAR; + reg |= RZG2L_ADIVC_DIVADC_4; + rzg2l_adc_writel(adc, RZG2L_ADIVC, reg); + + reg = rzg2l_adc_readl(adc, RZG2L_ADINT); + reg &= ~RZG2L_ADINT_INTS; + reg &= RZG2L_ADINT_CH_CLEAR; + reg |= RZG2L_ADINT_CSEEN; + reg |= BIT(ch); + rzg2l_adc_writel(adc, RZG2L_ADINT, reg); + + return 0; +} + +static int rzg2l_adc_set_power(struct iio_dev *indio_dev, bool on) +{ + struct device *dev = indio_dev->dev.parent; + + if (on) + return pm_runtime_resume_and_get(dev); + + return pm_runtime_put_sync(dev); +} + +static int rzg2l_adc_conversion(struct iio_dev *indio_dev, struct rzg2l_adc *adc, u8 ch) +{ + int ret; + + ret = rzg2l_adc_set_power(indio_dev, true); + if (ret) + return ret; + + ret = rzg2l_adc_conversion_setup(adc, ch); + if (ret) { + rzg2l_adc_set_power(indio_dev, false); + return ret; + } + + reinit_completion(&adc->completion); + + rzg2l_adc_start_stop(adc, true); + + if (!wait_for_completion_timeout(&adc->completion, RZG2L_ADC_TIMEOUT)) { + rzg2l_adc_writel(adc, RZG2L_ADINT, + rzg2l_adc_readl(adc, RZG2L_ADINT) & RZG2L_ADINT_CH_CLEAR); + rzg2l_adc_start_stop(adc, false); + rzg2l_adc_set_power(indio_dev, false); + return -ETIMEDOUT; + } + + return rzg2l_adc_set_power(indio_dev, false); +} + +static int rzg2l_adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct rzg2l_adc *adc = iio_priv(indio_dev); + int ret; + u8 ch; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (chan->type != IIO_VOLTAGE) + return -EINVAL; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + ch = chan->channel & RZG2L_ADC_CHN_MASK; + ret = rzg2l_adc_conversion(indio_dev, adc, ch); + if (ret) { + iio_device_release_direct_mode(indio_dev); + return ret; + } + *val = adc->last_val[ch]; + iio_device_release_direct_mode(indio_dev); + + return IIO_VAL_INT; + + default: + return -EINVAL; + } +} + +static int rzg2l_adc_read_label(struct iio_dev *iio_dev, + const struct iio_chan_spec *chan, + char *label) +{ + if (chan->channel >= RZG2L_ADC_MAX_CHANNELS) + return -EINVAL; + + return snprintf(label, PAGE_SIZE, "%s\n", rzg2l_adc_channel_name[chan->channel]); +} + +static const struct iio_info rzg2l_adc_iio_info = { + .read_raw = rzg2l_adc_read_raw, + .read_label = rzg2l_adc_read_label, +}; + +static irqreturn_t rzg2l_adc_isr(int irq, void *dev_id) +{ + struct rzg2l_adc *adc = (struct rzg2l_adc *)dev_id; + u8 intst; + u32 reg; + u8 i; + + reg = rzg2l_adc_readl(adc, RZG2L_ADSTS); + if (reg & RZG2L_ADSTS_CSEST) { + rzg2l_adc_writel(adc, RZG2L_ADSTS, reg); + return IRQ_HANDLED; + } + + intst = reg & RZG2L_ADINT_INTST_MASK; + if (!intst) + return IRQ_HANDLED; + + for (i = 0; i < RZG2L_ADC_MAX_CHANNELS; i++) { + if (intst & BIT(i)) + adc->last_val[i] = rzg2l_adc_readl(adc, RZG2L_ADCR(i)) & RZG2L_ADCR_AD_MASK; + } + + rzg2l_adc_writel(adc, RZG2L_ADSTS, reg); + + complete(&adc->completion); + + return IRQ_HANDLED; +} + +static int rzg2l_adc_parse_of(struct platform_device *pdev, struct rzg2l_adc *adc) +{ + struct iio_chan_spec *chan_array; + struct fwnode_handle *fwnode; + struct rzg2l_adc_data *data; + unsigned int channel; + int num_channels; + int ret; + u8 i; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + num_channels = device_get_child_node_count(&pdev->dev); + if (!num_channels) { + dev_err(&pdev->dev, "no channel children\n"); + return -ENODEV; + } + + if (num_channels > RZG2L_ADC_MAX_CHANNELS) { + dev_err(&pdev->dev, "num of channel children out of range\n"); + return -EINVAL; + } + + chan_array = devm_kcalloc(&pdev->dev, num_channels, sizeof(*chan_array), + GFP_KERNEL); + if (!chan_array) + return -ENOMEM; + + i = 0; + device_for_each_child_node(&pdev->dev, fwnode) { + ret = fwnode_property_read_u32(fwnode, "reg", &channel); + if (ret) + return ret; + + if (channel >= RZG2L_ADC_MAX_CHANNELS) + return -EINVAL; + + chan_array[i].type = IIO_VOLTAGE; + chan_array[i].indexed = 1; + chan_array[i].channel = channel; + chan_array[i].info_mask_separate = BIT(IIO_CHAN_INFO_RAW); + chan_array[i].datasheet_name = rzg2l_adc_channel_name[channel]; + i++; + } + + data->num_channels = num_channels; + data->channels = chan_array; + adc->data = data; + + return 0; +} + +static int rzg2l_adc_sw_reset(struct rzg2l_adc *adc) +{ + int timeout = 5; + u32 val; + + val = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + val |= RZG2L_ADM0_SRESB; + rzg2l_adc_writel(adc, RZG2L_ADM(0), val); + + while (!(rzg2l_adc_readl(adc, RZG2L_ADM(0)) & RZG2L_ADM0_SRESB)) { + if (!timeout) + return -EBUSY; + timeout--; + usleep_range(100, 200); + } + + return 0; +} + +static int rzg2l_adc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *indio_dev; + struct rzg2l_adc *adc; + int ret; + int irq; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*adc)); + if (!indio_dev) + return -ENOMEM; + + adc = iio_priv(indio_dev); + + ret = rzg2l_adc_parse_of(pdev, adc); + if (ret) + return ret; + + adc->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(adc->base)) + return PTR_ERR(adc->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "no irq resource\n"); + return irq; + } + + adc->pclk = devm_clk_get(dev, "pclk"); + if (IS_ERR(adc->pclk)) { + dev_err(dev, "Failed to get pclk"); + return PTR_ERR(adc->pclk); + } + + adc->adclk = devm_clk_get(dev, "adclk"); + if (IS_ERR(adc->adclk)) { + dev_err(dev, "Failed to get adclk"); + return PTR_ERR(adc->adclk); + } + + adc->adrstn = devm_reset_control_get_exclusive(dev, "adrst-n"); + if (IS_ERR(adc->adrstn)) { + dev_err(dev, "failed to get adrstn\n"); + return PTR_ERR(adc->adrstn); + } + + adc->presetn = devm_reset_control_get_exclusive(dev, "presetn"); + if (IS_ERR(adc->presetn)) { + dev_err(dev, "failed to get presetn\n"); + return PTR_ERR(adc->presetn); + } + + ret = reset_control_deassert(adc->adrstn); + if (ret) + return ret; + + ret = reset_control_deassert(adc->presetn); + if (ret) + goto assert_adrstn; + + ret = clk_prepare_enable(adc->pclk); + if (ret) + goto assert_presetn; + + ret = rzg2l_adc_sw_reset(adc); + if (ret) + goto unprepare_pclk; + + clk_disable_unprepare(adc->pclk); + + init_completion(&adc->completion); + + platform_set_drvdata(pdev, indio_dev); + + ret = devm_request_irq(dev, irq, rzg2l_adc_isr, + 0, dev_name(dev), adc); + if (ret < 0) + goto assert_presetn; + + indio_dev->name = DRIVER_NAME; + indio_dev->info = &rzg2l_adc_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = adc->data->channels; + indio_dev->num_channels = adc->data->num_channels; + + pm_runtime_enable(dev); + + ret = devm_iio_device_register(dev, indio_dev); + if (ret) + goto err_iio_device_register; + + return 0; + +unprepare_pclk: + clk_disable_unprepare(adc->pclk); +err_iio_device_register: + pm_runtime_disable(dev); +assert_presetn: + reset_control_assert(adc->presetn); +assert_adrstn: + reset_control_assert(adc->adrstn); + return ret; +} + +static int rzg2l_adc_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + + reset_control_assert(adc->presetn); + reset_control_assert(adc->adrstn); + pm_runtime_disable(indio_dev->dev.parent); + + return 0; +} + +static const struct of_device_id rzg2l_adc_match[] = { + { .compatible = "renesas,rzg2l-adc",}, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rzg2l_adc_match); + +static int __maybe_unused rzg2l_adc_pm_runtime_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + + rzg2l_adc_pwr(adc, false); + clk_disable_unprepare(adc->adclk); + clk_disable_unprepare(adc->pclk); + + return 0; +} + +static int __maybe_unused rzg2l_adc_pm_runtime_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + int ret; + + ret = clk_prepare_enable(adc->pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(adc->adclk); + if (ret) + return ret; + + rzg2l_adc_pwr(adc, true); + + return 0; +} + +static const struct dev_pm_ops rzg2l_adc_pm_ops = { + SET_RUNTIME_PM_OPS(rzg2l_adc_pm_runtime_suspend, + rzg2l_adc_pm_runtime_resume, + NULL) +}; + +static struct platform_driver rzg2l_adc_driver = { + .probe = rzg2l_adc_probe, + .remove = rzg2l_adc_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = rzg2l_adc_match, + .pm = &rzg2l_adc_pm_ops, + }, +}; + +module_platform_driver(rzg2l_adc_driver); + +MODULE_AUTHOR("Lad Prabhakar "); +MODULE_DESCRIPTION("Renesas RZ/G2L ADC driver"); +MODULE_LICENSE("GPL v2");