| Message ID | 2263220.rhyqmTfAiL@diego (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 09/07/14 11:22, Heiko Stübner 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 <heiko@sntech.de> 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? 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. 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 <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/of.h> > +#include <linux/clk.h> > +#include <linux/completion.h> > +#include <linux/regulator/consumer.h> > +#include <linux/iio/iio.h> > + > +#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); >
Am Samstag, 12. Juli 2014, 15:35:04 schrieb Jonathan Cameron: > On 09/07/14 11:22, Heiko Stübner 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 <heiko@sntech.de> > > 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 <linux/module.h> > > +#include <linux/platform_device.h> > > +#include <linux/interrupt.h> > > +#include <linux/io.h> > > +#include <linux/of.h> > > +#include <linux/clk.h> > > +#include <linux/completion.h> > > +#include <linux/regulator/consumer.h> > > +#include <linux/iio/iio.h> > > + > > +#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);
On July 12, 2014 4:14:58 PM GMT+01:00, "Heiko Stübner" <heiko@sntech.de> wrote: >Am Samstag, 12. Juli 2014, 15:35:04 schrieb Jonathan Cameron: >> On 09/07/14 11:22, Heiko Stübner 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 <heiko@sntech.de> >> >> 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? :-) > Which ever you prefer. Either will get hammered by the autobuilders so we will get plenty of test coverage. > > >> 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 <linux/module.h> >> > +#include <linux/platform_device.h> >> > +#include <linux/interrupt.h> >> > +#include <linux/io.h> >> > +#include <linux/of.h> >> > +#include <linux/clk.h> >> > +#include <linux/completion.h> >> > +#include <linux/regulator/consumer.h> >> > +#include <linux/iio/iio.h> >> > + >> > +#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-iio" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html
Heiko Stübner schrieb: > 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. Is there a datasheet available anywhere, or just under some NDA? I've got some comments in line, which might be answered by reading the datasheet. > Signed-off-by: Heiko Stuebner <heiko@sntech.de> > --- > 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. Does this mean, that you are working for Rockchip? > + * > + * 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 <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/of.h> > +#include <linux/clk.h> > +#include <linux/completion.h> > +#include <linux/regulator/consumer.h> > +#include <linux/iio/iio.h> > + > +#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); This could need a bit more explanation. Maybe represent the magic value of 0x8 with a more self explaining definition. > + 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; Are there only fixed voltage regulators used, or are there chances that variable voltage regulators could be used for vref? In the second case, it would be better to determine the current regulator voltage here. > + 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; return -ENODEV is usually used, and a bit more obvious. That would also make the initialization of ret obsolete. > + > + 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; > + > + 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);
Am Sonntag, 13. Juli 2014, 14:09:48 schrieb Hartmut Knaack: > Heiko Stübner schrieb: > > 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. > Is there a datasheet available anywhere, or just under some NDA? I've got > some comments in line, which might be answered by reading the datasheet. Sadly, there is no datasheet available to the public. > > Signed-off-by: Heiko Stuebner <heiko@sntech.de> > > --- > > > > 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. > > Does this mean, that you are working for Rockchip? I'm doing consulting on the mainline integration and the code is largely the one taken from the upstream tree and only cleaned up in places. > > > + * > > + * 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 <linux/module.h> > > +#include <linux/platform_device.h> > > +#include <linux/interrupt.h> > > +#include <linux/io.h> > > +#include <linux/of.h> > > +#include <linux/clk.h> > > +#include <linux/completion.h> > > +#include <linux/regulator/consumer.h> > > +#include <linux/iio/iio.h> > > + > > +#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); > > This could need a bit more explanation. Maybe represent the magic value of > 0x8 with a more self explaining definition. This actually isn't a magic value, but the "delay between power up and start command" in clock periods. But you're right, this might benefit from a better explaination, as the channel selection and start is done by the setting below. > > + 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; > > Are there only fixed voltage regulators used, or are there chances that > variable voltage regulators could be used for vref? In the second case, it > would be better to determine the current regulator voltage here. The voltage regulators used are generally variable, but set to a fixed setting that is not supposed to be changed. Nevertheless I think you're right and the driver could be prepared for the case where the voltage might really change. > > + 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; > > return -ENODEV is usually used, and a bit more obvious. That would also make > the initialization of ret obsolete. ok Thanks for the review Heiko > > + > > + 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; > > + > > + 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);
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 <linux/module.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/regulator/consumer.h> +#include <linux/iio/iio.h> + +#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; + + 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);
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 <heiko@sntech.de> --- 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