Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752893AbaGLPNj (ORCPT ); Sat, 12 Jul 2014 11:13:39 -0400 Received: from gloria.sntech.de ([95.129.55.99]:39997 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751142AbaGLPNh convert rfc822-to-8bit (ORCPT ); Sat, 12 Jul 2014 11:13:37 -0400 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Jonathan Cameron Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , =?utf-8?B?ZWRkaWUo6JSh5p6rKQ==?= , huangtao@rock-chips.com, Peter Meerwald Subject: Re: [PATCH v3 1/2] iio: adc: add driver for Rockchip saradc Date: Sat, 12 Jul 2014 17:14:58 +0200 Message-ID: <6420933.hxc5MxPS5k@diego> User-Agent: KMail/4.11.5 (Linux/3.13-1-amd64; KDE/4.11.3; x86_64; ; ) In-Reply-To: <53C14798.7070706@kernel.org> References: <2959154.xc8BQActsn@diego> <2263220.rhyqmTfAiL@diego> <53C14798.7070706@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Samstag, 12. Juli 2014, 15:35:04 schrieb Jonathan Cameron: > On 09/07/14 11:22, Heiko St?bner wrote: > > The ADC is a 3-channel signal-ended 10-bit Successive Approximation > > Register (SAR) A/D Converter. It uses the supply and ground as its > > reference and converts the analog input signal into 10-bit binary digital > > codes. > > > > Signed-off-by: Heiko Stuebner > > Very nice. One utterly trivial comment inline that doesn't really > bother me (made the review take a good 10 seconds longer than it > otherwise would have done!) > > Ah, and as my build tests (x86_64) just finished, a build issue: > > drivers/iio/adc/rockchip_saradc.c:65:17: error: undefined identifier > 'writel_relaxed' drivers/iio/adc/rockchip_saradc.c:73:25: error: undefined > identifier 'writel_relaxed' drivers/iio/adc/rockchip_saradc.c:99:9: error: > undefined identifier 'writel_relaxed' > > I can't immediately identify if there is a CONFIG element to indicate > the availability of the relaxed form. Anyone else know? taking a spi driver from another architecture (spi_qup), I see config SPI_QUP depends on ARCH_QCOM || (ARM && COMPILE_TEST) A fix Mark Brown did for the actual rockchip spi driver does config SPI_ROCKCHIP depends on ARM || ARM64 || AVR32 || HEXAGON || MIPS || SUPERH so I guess the saradc also could do one of the two ... preferences? :-) > I'm in two minds on whether the binding is obvous enough to take without > a device-tree maintainer ack. I'll let it sit for a bit - perhaps > even the standard 3 weeks (please repost with the typos fixed though) > and see if anyone want to comment. ok, so I'll repost the two patches, fixing the typos and Kconfig and changing the of_property_read_u32 behaviour. Heiko > > Jonathan > > > --- > > > > changes since v2: > > - address more comments from Peter Meerwald > > > > mainly the missing info_mask_shared_by_type element > > > > changes since v1: > > - address comments from Peter Meerwald > > > > drivers/iio/adc/Kconfig | 10 ++ > > > > drivers/iio/adc/Makefile | 1 + > > drivers/iio/adc/rockchip_saradc.c | 314 > > ++++++++++++++++++++++++++++++++++++++ 3 files changed, 325 > > insertions(+) > > create mode 100644 drivers/iio/adc/rockchip_saradc.c > > > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > > index a80d236..5d36bdb 100644 > > --- a/drivers/iio/adc/Kconfig > > +++ b/drivers/iio/adc/Kconfig > > @@ -187,6 +187,16 @@ config NAU7802 > > > > To compile this driver as a module, choose M here: the > > module will be called nau7802. > > > > +config ROCKCHIP_SARADC > > + tristate "Rockchip SARADC driver" > > + depends on ARCH_ROCKCHIP || (OF && COMPILE_TEST) > > + help > > + Say yes here to build support for the SARADC found in SoCs from > > + Rockchip. > > + > > + To compile this driver as a module, choose M here: the > > + module will be called rockchip_saradc. > > + > > > > config TI_ADC081C > > > > tristate "Texas Instruments ADC081C021/027" > > depends on I2C > > > > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > > index 9d60f2d..8e2932d 100644 > > --- a/drivers/iio/adc/Makefile > > +++ b/drivers/iio/adc/Makefile > > @@ -20,6 +20,7 @@ obj-$(CONFIG_MCP320X) += mcp320x.o > > > > obj-$(CONFIG_MCP3422) += mcp3422.o > > obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o > > obj-$(CONFIG_NAU7802) += nau7802.o > > > > +obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o > > > > obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o > > obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o > > obj-$(CONFIG_TWL4030_MADC) += twl4030-madc.o > > > > diff --git a/drivers/iio/adc/rockchip_saradc.c > > b/drivers/iio/adc/rockchip_saradc.c new file mode 100644 > > index 0000000..8fc5867 > > --- /dev/null > > +++ b/drivers/iio/adc/rockchip_saradc.c > > @@ -0,0 +1,314 @@ > > +/* > > + * Rockchip Successive Approximation Register (SAR) A/D Converter > > + * Copyright (C) 2014 ROCKCHIP, Inc. > > + * > > + * This program is free software; you can redistribute it and/or modify > > + * it under the terms of the GNU General Public License as published by > > + * the Free Software Foundation; either version 2 of the License, or > > + * (at your option) any later version. > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +#define SARADC_DATA 0x00 > > +#define SARADC_DATA_MASK 0x3ff > > + > > +#define SARADC_STAS 0x04 > > +#define SARADC_STAS_BUSY BIT(0) > > + > > +#define SARADC_CTRL 0x08 > > +#define SARADC_CTRL_IRQ_STATUS BIT(6) > > +#define SARADC_CTRL_IRQ_ENABLE BIT(5) > > +#define SARADC_CTRL_POWER_CTRL BIT(3) > > +#define SARADC_CTRL_CHN_MASK 0x7 > > + > > +#define SARADC_DLY_PU_SOC 0x0c > > +#define SARADC_DLY_PU_SOC_MASK 0x3f > > + > > +#define SARADC_BITS 10 > > +#define SARADC_TIMEOUT msecs_to_jiffies(100) > > + > > +struct rockchip_saradc { > > + void __iomem *regs; > > + struct clk *pclk; > > + struct clk *clk; > > + struct completion completion; > > + struct regulator *vref; > > + int vref_mv; > > + u16 last_val; > > +}; > > + > > +static int rockchip_saradc_read_raw(struct iio_dev *indio_dev, > > + struct iio_chan_spec const *chan, > > + int *val, int *val2, long mask) > > +{ > > + struct rockchip_saradc *info = iio_priv(indio_dev); > > + > > + switch (mask) { > > + case IIO_CHAN_INFO_RAW: > > + mutex_lock(&indio_dev->mlock); > > + > > + /* Select the channel to be used and trigger conversion */ > > + writel_relaxed(0x08, info->regs + SARADC_DLY_PU_SOC); > > + writel(SARADC_CTRL_POWER_CTRL > > + | (chan->channel & SARADC_CTRL_CHN_MASK) > > + | SARADC_CTRL_IRQ_ENABLE, > > + info->regs + SARADC_CTRL); > > + > > + if (!wait_for_completion_timeout(&info->completion, > > + SARADC_TIMEOUT)) { > > + writel_relaxed(0, info->regs + SARADC_CTRL); > > + mutex_unlock(&indio_dev->mlock); > > + return -ETIMEDOUT; > > + } > > + > > + *val = info->last_val; > > + mutex_unlock(&indio_dev->mlock); > > + return IIO_VAL_INT; > > + case IIO_CHAN_INFO_SCALE: > > + *val = info->vref_mv; > > + *val2 = SARADC_BITS; > > + return IIO_VAL_FRACTIONAL_LOG2; > > + default: > > + return -EINVAL; > > + } > > +} > > + > > +static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id) > > +{ > > + struct rockchip_saradc *info = (struct rockchip_saradc *)dev_id; > > + > > + /* Read value */ > > + info->last_val = readl_relaxed(info->regs + SARADC_DATA); > > + info->last_val &= SARADC_DATA_MASK; > > + > > + /* Clear irq & power down adc */ > > + writel_relaxed(0, info->regs + SARADC_CTRL); > > + > > + complete(&info->completion); > > + > > + return IRQ_HANDLED; > > +} > > + > > +static const struct iio_info rockchip_saradc_iio_info = { > > + .read_raw = rockchip_saradc_read_raw, > > + .driver_module = THIS_MODULE, > > +}; > > + > > +#define ADC_CHANNEL(_index, _id) { \ > > + .type = IIO_VOLTAGE, \ > > + .indexed = 1, \ > > + .channel = _index, \ > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > > + .datasheet_name = _id, \ > > +} > > + > > +static const struct iio_chan_spec rockchip_saradc_iio_channels[] = { > > + ADC_CHANNEL(0, "adc0"), > > + ADC_CHANNEL(1, "adc1"), > > + ADC_CHANNEL(2, "adc2"), > > +}; > > + > > +static int rockchip_saradc_probe(struct platform_device *pdev) > > +{ > > + struct rockchip_saradc *info = NULL; > > + struct device_node *np = pdev->dev.of_node; > > + struct iio_dev *indio_dev = NULL; > > + struct resource *mem; > > + int ret = -ENODEV; > > + int irq; > > + u32 rate; > > + > > + if (!np) > > + return ret; > > + > > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); > > + if (!indio_dev) { > > + dev_err(&pdev->dev, "failed allocating iio device\n"); > > + return -ENOMEM; > > + } > > + info = iio_priv(indio_dev); > > + > > + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > + info->regs = devm_request_and_ioremap(&pdev->dev, mem); > > + if (!info->regs) > > + return -ENOMEM; > > + > > + irq = platform_get_irq(pdev, 0); > > + if (irq < 0) { > > + dev_err(&pdev->dev, "no irq resource?\n"); > > + return irq; > > + } > > + > > + ret = devm_request_irq(&pdev->dev, irq, rockchip_saradc_isr, > > + 0, dev_name(&pdev->dev), info); > > + if (ret < 0) { > > + dev_err(&pdev->dev, "failed requesting irq %d\n", irq); > > + return ret; > > + } > > + > > + init_completion(&info->completion); > > + > > + info->pclk = devm_clk_get(&pdev->dev, "apb_pclk"); > > + if (IS_ERR(info->pclk)) { > > + dev_err(&pdev->dev, "failed to get pclk\n"); > > + return PTR_ERR(info->pclk); > > + } > > + > > + info->clk = devm_clk_get(&pdev->dev, "saradc"); > > + if (IS_ERR(info->clk)) { > > + dev_err(&pdev->dev, "failed to get adc clock\n"); > > + return PTR_ERR(info->clk); > > + } > > + > > + info->vref = devm_regulator_get(&pdev->dev, "vref"); > > + if (IS_ERR(info->vref)) { > > + dev_err(&pdev->dev, "failed to get regulator, %ld\n", > > + PTR_ERR(info->vref)); > > + return PTR_ERR(info->vref); > > + } > > + > > + /* use a default of 1MHz for the converter clock */ > > + if (of_property_read_u32(np, "clock-frequency", &rate)) > > + rate = 1000000; > > I'd have a very slight preference of checking for an error rather > than simply non zero (i.e. < 0). The function is clearly > documented as returning 0 for success however. The only > reason I carred is that I had to check that rather than relying > on the tighter standard convention! > > > + > > + ret = clk_set_rate(info->clk, rate); > > + if (ret) { > > + dev_err(&pdev->dev, "failed to set adc clk rate, %d\n", ret); > > + return ret; > > + } > > + > > + ret = regulator_enable(info->vref); > > + if (ret) { > > + dev_err(&pdev->dev, "failed to enable vref regulator\n"); > > + return ret; > > + } > > + > > + ret = regulator_get_voltage(info->vref); > > + if (ret < 0) { > > + dev_err(&pdev->dev, "failed to get regulator voltage\n"); > > + goto err_reg_voltage; > > + } > > + info->vref_mv = ret / 1000; > > + > > + ret = clk_prepare_enable(info->pclk); > > + if (ret) { > > + dev_err(&pdev->dev, "failed to enable pclk\n"); > > + goto err_reg_voltage; > > + } > > + > > + ret = clk_prepare_enable(info->clk); > > + if (ret) { > > + dev_err(&pdev->dev, "failed to enable converter clock\n"); > > + goto err_pclk; > > + } > > + > > + platform_set_drvdata(pdev, indio_dev); > > + > > + indio_dev->name = dev_name(&pdev->dev); > > + indio_dev->dev.parent = &pdev->dev; > > + indio_dev->dev.of_node = pdev->dev.of_node; > > + indio_dev->info = &rockchip_saradc_iio_info; > > + indio_dev->modes = INDIO_DIRECT_MODE; > > + > > + indio_dev->channels = rockchip_saradc_iio_channels; > > + indio_dev->num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels); > > + > > + ret = iio_device_register(indio_dev); > > + if (ret) > > + goto err_clk; > > + > > + return 0; > > + > > +err_clk: > > + clk_disable_unprepare(info->clk); > > +err_pclk: > > + clk_disable_unprepare(info->pclk); > > +err_reg_voltage: > > + regulator_disable(info->vref); > > + return ret; > > +} > > + > > +static int rockchip_saradc_remove(struct platform_device *pdev) > > +{ > > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > > + struct rockchip_saradc *info = iio_priv(indio_dev); > > + > > + iio_device_unregister(indio_dev); > > + clk_disable_unprepare(info->clk); > > + clk_disable_unprepare(info->pclk); > > + regulator_disable(info->vref); > > + > > + return 0; > > +} > > + > > +#ifdef CONFIG_PM_SLEEP > > +static int rockchip_saradc_suspend(struct device *dev) > > +{ > > + struct iio_dev *indio_dev = dev_get_drvdata(dev); > > + struct rockchip_saradc *info = iio_priv(indio_dev); > > + > > + clk_disable_unprepare(info->clk); > > + clk_disable_unprepare(info->pclk); > > + regulator_disable(info->vref); > > + > > + return 0; > > +} > > + > > +static int rockchip_saradc_resume(struct device *dev) > > +{ > > + struct iio_dev *indio_dev = dev_get_drvdata(dev); > > + struct rockchip_saradc *info = iio_priv(indio_dev); > > + int ret; > > + > > + ret = regulator_enable(info->vref); > > + if (ret) > > + return ret; > > + > > + ret = clk_prepare_enable(info->pclk); > > + if (ret) > > + return ret; > > + > > + ret = clk_prepare_enable(info->clk); > > + if (ret) > > + return ret; > > + > > + return ret; > > +} > > +#endif > > + > > +static SIMPLE_DEV_PM_OPS(rockchip_saradc_pm_ops, > > + rockchip_saradc_suspend, rockchip_saradc_resume); > > + > > +static const struct of_device_id rockchip_saradc_match[] = { > > + { .compatible = "rockchip,saradc" }, > > + {}, > > +}; > > +MODULE_DEVICE_TABLE(of, rockchip_saradc_match); > > + > > +static struct platform_driver rockchip_saradc_driver = { > > + .probe = rockchip_saradc_probe, > > + .remove = rockchip_saradc_remove, > > + .driver = { > > + .name = "rockchip-saradc", > > + .owner = THIS_MODULE, > > + .of_match_table = rockchip_saradc_match, > > + .pm = &rockchip_saradc_pm_ops, > > + }, > > +}; > > + > > +module_platform_driver(rockchip_saradc_driver); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/