| Message ID | 1473943444-23979-3-git-send-email-quentin.schulz@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 15/09/16 13:44, Quentin Schulz wrote: > The Allwinner SoCs all have an ADC that can also act as a touchscreen > controller and a thermal sensor. This patch adds the ADC driver which is > based on the MFD for the same SoCs ADC. > > This also registers the thermal adc channel in the iio map array so > iio_hwmon could use it without modifying the Device Tree. This registers > the driver in the thermal framework. > > This driver probes on three different platform_device_id to take into > account slight differences (registers bit and temperature computation) > between Allwinner SoCs ADCs. > > Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> > Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> > Acked-by: Jonathan Cameron <jic23@kernel.org> Hi Lee, As you applied the MFD part of this series, could you pick this up as well? Thanks, Jonathan > --- > > v6: > - remove useless member (regs) from sun4i_gpadc_dev structure, > - rename sun4i_gpadc_dev structure to sun4i_gpadc_iio, > - remove regmap_update_bits used to disable hardware interrupts, it is already > handled by devm functions, > > v5: > - correct mail address, > - correct several typos, > - move from const to static for sunxi_gpadc_chan_select functions, > - rename soc_specific struct to gpadc_data, > - rename soc_specific field to data in sun4i_gpadc_dev, > - return error code from regmap_write in case of failure in read_raws, > - share if condition in IIO_CHAN_INFO_RAW case, > - add comment on why we use parent device for registering in thermal, > - reordering remove function, > > v4: > - rename files and variables from sunxi* to sun4i*, > - shorten sunxi_gpadc_soc_specific structure to soc_specific, > - factorize sysfs ADC and temp read_raws, > - use cached values when read_raw times out (except before a first value > is gotten), > - remove mutex locks and unlocks from runtime_pm functions, > - factorize irq initializations, > - initialize temp_data and fifo_data values to -1 (error value), > - "impersonate" MFD to register in thermal framework, > - deactivate hardware interrupts one by one when probe fails or when > removing driver instead of blindly deactivating all hardware interrupts, > - selects THERMAL_OF in Kconfig, > > v3: > - correct wrapping, > - add comment about thermal sensor inner working, > - move defines in mfd header, > - use structure to define SoC specific registers or behaviour, > - attach this structure to the device according to of_device_id of the > platform device, > - use new mutex instead of iio_dev mutex, > - use atomic flags to avoid race between request_irq and disable_irq in > probe, > - switch from processed value to raw, offset and scale values for > temperature ADC channel, > - remove faulty sentinel in iio_chan_spec array, > - add pm_runtime support, > - register thermal sensor in thermal framework (forgotten since the > beginning whereas it is present in current sun4i-ts driver), > - remove useless ret variables to store return value of regmap_reads, > - move comments on thermal sensor acquisition period in code instead of > header, > - adding goto label to unregister iio_map_array when failing to register > iio_dev, > > v2: > - add SUNXI_GPADC_ prefixes for defines, > - correct typo in Kconfig, > - reorder alphabetically includes, makefile, > - add license header, > - fix architecture variations not being handled in interrupt handlers or > read raw functions, > - fix unability to return negative values from thermal sensor, > - add gotos to reduce code repetition, > - fix irq variable being unsigned int instead of int, > - remove useless dev_err and dev_info, > - deactivate all interrupts if probe fails, > - fix iio_device_register on NULL variable, > - deactivate ADC in the IP when probe fails or when removing driver, > > drivers/iio/adc/Kconfig | 13 + > drivers/iio/adc/Makefile | 1 + > drivers/iio/adc/sun4i-gpadc-iio.c | 522 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 536 insertions(+) > create mode 100644 drivers/iio/adc/sun4i-gpadc-iio.c > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 25378c5..ea36a4f 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -384,6 +384,19 @@ config ROCKCHIP_SARADC > To compile this driver as a module, choose M here: the > module will be called rockchip_saradc. > > +config SUN4I_GPADC > + tristate "Support for the Allwinner SoCs GPADC" > + depends on IIO > + depends on MFD_SUN4I_GPADC > + select THERMAL_OF > + help > + Say yes here to build support for Allwinner (A10, A13 and A31) SoCs > + GPADC. This ADC provides 4 channels which can be used as an ADC or as > + a touchscreen input and one channel for thermal sensor. > + > + To compile this driver as a module, choose M here: the module will be > + called sun4i-gpadc-iio. > + > config TI_ADC081C > tristate "Texas Instruments ADC081C/ADC101C/ADC121C family" > depends on I2C > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > index 38638d4..204372d 100644 > --- a/drivers/iio/adc/Makefile > +++ b/drivers/iio/adc/Makefile > @@ -37,6 +37,7 @@ obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o > obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o > obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o > obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o > +obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o > obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o > obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o > obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o > diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c > new file mode 100644 > index 0000000..e2c5ba8 > --- /dev/null > +++ b/drivers/iio/adc/sun4i-gpadc-iio.c > @@ -0,0 +1,522 @@ > +/* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC > + * > + * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com> > + * > + * This program is free software; you can redistribute it and/or modify it under > + * the terms of the GNU General Public License version 2 as published by the > + * Free Software Foundation. > + * > + * The Allwinner SoCs all have an ADC that can also act as a touchscreen > + * controller and a thermal sensor. > + * The thermal sensor works only when the ADC acts as a touchscreen controller > + * and is configured to throw an interrupt every fixed periods of time (let say > + * every X seconds). > + * One would be tempted to disable the IP on the hardware side rather than > + * disabling interrupts to save some power but that resets the internal clock of > + * the IP, resulting in having to wait X seconds every time we want to read the > + * value of the thermal sensor. > + * This is also the reason of using autosuspend in pm_runtime. If there was no > + * autosuspend, the thermal sensor would need X seconds after every > + * pm_runtime_get_sync to get a value from the ADC. The autosuspend allows the > + * thermal sensor to be requested again in a certain time span before it gets > + * shutdown for not being used. > + */ > + > +#include <linux/completion.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> > +#include <linux/pm_runtime.h> > +#include <linux/regmap.h> > +#include <linux/thermal.h> > + > +#include <linux/iio/iio.h> > +#include <linux/iio/driver.h> > +#include <linux/iio/machine.h> > +#include <linux/mfd/sun4i-gpadc.h> > + > +static unsigned int sun4i_gpadc_chan_select(unsigned int chan) > +{ > + return SUN4I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); > +} > + > +static unsigned int sun6i_gpadc_chan_select(unsigned int chan) > +{ > + return SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); > +} > + > +struct gpadc_data { > + int temp_offset; > + int temp_scale; > + unsigned int tp_mode_en; > + unsigned int tp_adc_select; > + unsigned int (*adc_chan_select)(unsigned int chan); > +}; > + > +static const struct gpadc_data sun4i_gpadc_data = { > + .temp_offset = -1932, > + .temp_scale = 133, > + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, > + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, > + .adc_chan_select = &sun4i_gpadc_chan_select, > +}; > + > +static const struct gpadc_data sun5i_gpadc_data = { > + .temp_offset = -1447, > + .temp_scale = 100, > + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, > + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, > + .adc_chan_select = &sun4i_gpadc_chan_select, > +}; > + > +static const struct gpadc_data sun6i_gpadc_data = { > + .temp_offset = -1623, > + .temp_scale = 167, > + .tp_mode_en = SUN6I_GPADC_CTRL1_TP_MODE_EN, > + .tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT, > + .adc_chan_select = &sun6i_gpadc_chan_select, > +}; > + > +struct sun4i_gpadc_iio { > + struct iio_dev *indio_dev; > + struct completion completion; > + int temp_data; > + u32 adc_data; > + struct regmap *regmap; > + unsigned int fifo_data_irq; > + atomic_t ignore_fifo_data_irq; > + unsigned int temp_data_irq; > + atomic_t ignore_temp_data_irq; > + const struct gpadc_data *data; > + /* prevents concurrent reads of temperature and ADC */ > + struct mutex mutex; > +}; > + > +#define SUN4I_GPADC_ADC_CHANNEL(_channel, _name) { \ > + .type = IIO_VOLTAGE, \ > + .indexed = 1, \ > + .channel = _channel, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .datasheet_name = _name, \ > +} > + > +static struct iio_map sun4i_gpadc_hwmon_maps[] = { > + { > + .adc_channel_label = "temp_adc", > + .consumer_dev_name = "iio_hwmon.0", > + }, > + { /* sentinel */ }, > +}; > + > +static const struct iio_chan_spec sun4i_gpadc_channels[] = { > + SUN4I_GPADC_ADC_CHANNEL(0, "adc_chan0"), > + SUN4I_GPADC_ADC_CHANNEL(1, "adc_chan1"), > + SUN4I_GPADC_ADC_CHANNEL(2, "adc_chan2"), > + SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"), > + { > + .type = IIO_TEMP, > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | > + BIT(IIO_CHAN_INFO_SCALE) | > + BIT(IIO_CHAN_INFO_OFFSET), > + .datasheet_name = "temp_adc", > + }, > +}; > + > +static int sun4i_gpadc_read(struct iio_dev *indio_dev, int channel, int *val, > + unsigned int irq) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); > + int ret = 0; > + > + pm_runtime_get_sync(indio_dev->dev.parent); > + mutex_lock(&info->mutex); > + > + reinit_completion(&info->completion); > + > + ret = regmap_write(info->regmap, SUN4I_GPADC_INT_FIFOC, > + SUN4I_GPADC_INT_FIFOC_TP_FIFO_TRIG_LEVEL(1) | > + SUN4I_GPADC_INT_FIFOC_TP_FIFO_FLUSH); > + if (ret) > + return ret; > + > + if (irq == info->fifo_data_irq) { > + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, > + info->data->tp_mode_en | > + info->data->tp_adc_select | > + info->data->adc_chan_select(channel)); > + } else { > + /* > + * The temperature sensor returns valid data only when the ADC > + * operates in touchscreen mode. > + */ > + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, > + info->data->tp_mode_en); > + } > + > + if (ret) > + return ret; > + > + enable_irq(irq); > + > + if (!wait_for_completion_timeout(&info->completion, > + msecs_to_jiffies(100))) { > + if ((irq == info->fifo_data_irq && info->adc_data == -1) || > + (irq == info->temp_data_irq && info->temp_data == -1)) { > + ret = -ETIMEDOUT; > + goto out; > + } > + } > + > + if (irq == info->fifo_data_irq) > + *val = info->adc_data; > + else > + *val = info->temp_data; > + > + ret = 0; > + > +out: > + disable_irq(irq); > + mutex_unlock(&info->mutex); > + pm_runtime_mark_last_busy(indio_dev->dev.parent); > + pm_runtime_put_autosuspend(indio_dev->dev.parent); > + > + return ret; > +} > + > +static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel, > + int *val) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); > + > + return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq); > +} > + > +static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); > + > + return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq); > +} > + > +static int sun4i_gpadc_temp_offset(struct iio_dev *indio_dev, int *val) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); > + > + *val = info->data->temp_offset; > + > + return 0; > +} > + > +static int sun4i_gpadc_temp_scale(struct iio_dev *indio_dev, int *val) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); > + > + *val = info->data->temp_scale; > + > + return 0; > +} > + > +static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, int *val, > + int *val2, long mask) > +{ > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_OFFSET: > + ret = sun4i_gpadc_temp_offset(indio_dev, val); > + if (ret) > + return ret; > + > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_RAW: > + if (chan->type == IIO_VOLTAGE) > + ret = sun4i_gpadc_adc_read(indio_dev, chan->channel, > + val); > + else > + ret = sun4i_gpadc_temp_read(indio_dev, val); > + > + if (ret) > + return ret; > + > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + ret = sun4i_gpadc_temp_scale(indio_dev, val); > + if (ret) > + return ret; > + > + return IIO_VAL_INT; > + default: > + return -EINVAL; > + } > + > + return -EINVAL; > +} > + > +static const struct iio_info sun4i_gpadc_iio_info = { > + .read_raw = sun4i_gpadc_read_raw, > + .driver_module = THIS_MODULE, > +}; > + > +static irqreturn_t sun4i_gpadc_temp_data_irq_handler(int irq, void *dev_id) > +{ > + struct sun4i_gpadc_iio *info = dev_id; > + > + if (atomic_read(&info->ignore_temp_data_irq)) > + return IRQ_HANDLED; > + > + if (!regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, &info->temp_data)) > + complete(&info->completion); > + > + return IRQ_HANDLED; > +} > + > +static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id) > +{ > + struct sun4i_gpadc_iio *info = dev_id; > + > + if (atomic_read(&info->ignore_fifo_data_irq)) > + return IRQ_HANDLED; > + > + if (!regmap_read(info->regmap, SUN4I_GPADC_DATA, &info->adc_data)) > + complete(&info->completion); > + > + return IRQ_HANDLED; > +} > + > +static int sun4i_gpadc_runtime_suspend(struct device *dev) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); > + > + /* Disable the ADC on IP */ > + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, 0); > + /* Disable temperature sensor on IP */ > + regmap_write(info->regmap, SUN4I_GPADC_TPR, 0); > + > + return 0; > +} > + > +static int sun4i_gpadc_runtime_resume(struct device *dev) > +{ > + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); > + > + /* clkin = 6MHz */ > + regmap_write(info->regmap, SUN4I_GPADC_CTRL0, > + SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(2) | > + SUN4I_GPADC_CTRL0_FS_DIV(7) | > + SUN4I_GPADC_CTRL0_T_ACQ(63)); > + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, info->data->tp_mode_en); > + regmap_write(info->regmap, SUN4I_GPADC_CTRL3, > + SUN4I_GPADC_CTRL3_FILTER_EN | > + SUN4I_GPADC_CTRL3_FILTER_TYPE(1)); > + /* period = SUN4I_GPADC_TPR_TEMP_PERIOD * 256 * 16 / clkin; ~1.3s */ > + regmap_write(info->regmap, SUN4I_GPADC_TPR, > + SUN4I_GPADC_TPR_TEMP_ENABLE | > + SUN4I_GPADC_TPR_TEMP_PERIOD(1953)); > + > + return 0; > +} > + > +static int sun4i_gpadc_get_temp(void *data, int *temp) > +{ > + struct sun4i_gpadc_iio *info = (struct sun4i_gpadc_iio *)data; > + int val, scale, offset; > + > + /* If reading temperature times out, take stored previous value. */ > + if (sun4i_gpadc_temp_read(info->indio_dev, &val)) > + val = info->temp_data; > + sun4i_gpadc_temp_scale(info->indio_dev, &scale); > + sun4i_gpadc_temp_offset(info->indio_dev, &offset); > + > + *temp = (val + offset) * scale; > + > + return 0; > +} > + > +static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { > + .get_temp = &sun4i_gpadc_get_temp, > +}; > + > +static const struct dev_pm_ops sun4i_gpadc_pm_ops = { > + .runtime_suspend = &sun4i_gpadc_runtime_suspend, > + .runtime_resume = &sun4i_gpadc_runtime_resume, > +}; > + > +static int sun4i_irq_init(struct platform_device *pdev, const char *name, > + irq_handler_t handler, const char *devname, > + unsigned int *irq, atomic_t *atomic) > +{ > + int ret; > + struct sun4i_gpadc_dev *mfd_dev = dev_get_drvdata(pdev->dev.parent); > + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(&pdev->dev)); > + > + /* > + * Once the interrupt is activated, the IP continuously performs > + * conversions thus throws interrupts. The interrupt is activated right > + * after being requested but we want to control when these interrupts > + * occur thus we disable it right after being requested. However, an > + * interrupt might occur between these two instructions and we have to > + * make sure that does not happen, by using atomic flags. We set the > + * flag before requesting the interrupt and unset it right after > + * disabling the interrupt. When an interrupt occurs between these two > + * instructions, reading the atomic flag will tell us to ignore the > + * interrupt. > + */ > + atomic_set(atomic, 1); > + > + *irq = platform_get_irq_byname(pdev, name); > + if (*irq < 0) { > + dev_err(&pdev->dev, "no %s interrupt registered\n", name); > + return *irq; > + } > + > + *irq = regmap_irq_get_virq(mfd_dev->regmap_irqc, *irq); > + ret = devm_request_any_context_irq(&pdev->dev, *irq, handler, 0, > + devname, info); > + if (ret < 0) { > + dev_err(&pdev->dev, "could not request %s interrupt: %d\n", > + name, ret); > + return ret; > + } > + > + disable_irq(*irq); > + atomic_set(atomic, 0); > + > + return 0; > +} > + > +static int sun4i_gpadc_probe(struct platform_device *pdev) > +{ > + struct sun4i_gpadc_iio *info; > + struct iio_dev *indio_dev; > + int ret; > + struct sun4i_gpadc_dev *sun4i_gpadc_dev; > + struct thermal_zone_device *tzd; > + > + sun4i_gpadc_dev = dev_get_drvdata(pdev->dev.parent); > + > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); > + if (!indio_dev) > + return -ENOMEM; > + > + info = iio_priv(indio_dev); > + platform_set_drvdata(pdev, indio_dev); > + > + mutex_init(&info->mutex); > + info->regmap = sun4i_gpadc_dev->regmap; > + info->indio_dev = indio_dev; > + info->temp_data = -1; > + info->adc_data = -1; > + init_completion(&info->completion); > + 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 = &sun4i_gpadc_iio_info; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->num_channels = ARRAY_SIZE(sun4i_gpadc_channels); > + indio_dev->channels = sun4i_gpadc_channels; > + > + info->data = (struct gpadc_data *)platform_get_device_id(pdev)->driver_data; > + > + /* > + * This driver is a child of an MFD which has a node in the DT but not > + * its children. Therefore, the resulting devices of this driver do not > + * have an of_node variable. > + * However, its parent (the MFD driver) has an of_node variable and > + * since devm_thermal_zone_of_sensor_register uses its first argument to > + * match the phandle defined in the node of the thermal driver with the > + * of_node of the device passed as first argument and the third argument > + * to call ops from thermal_zone_of_device_ops, the solution is to use > + * the parent device as first argument to match the phandle with its > + * of_node, and the device from this driver as third argument to return > + * the temperature. > + */ > + tzd = devm_thermal_zone_of_sensor_register(pdev->dev.parent, 0, info, > + &sun4i_ts_tz_ops); > + if (IS_ERR(tzd)) { > + dev_err(&pdev->dev, "could not register thermal sensor: %ld\n", > + PTR_ERR(tzd)); > + return PTR_ERR(tzd); > + } > + > + pm_runtime_set_autosuspend_delay(&pdev->dev, > + SUN4I_GPADC_AUTOSUSPEND_DELAY); > + pm_runtime_use_autosuspend(&pdev->dev); > + pm_runtime_set_suspended(&pdev->dev); > + pm_runtime_enable(&pdev->dev); > + > + ret = sun4i_irq_init(pdev, "TEMP_DATA_PENDING", > + sun4i_gpadc_temp_data_irq_handler, "temp_data", > + &info->temp_data_irq, &info->ignore_temp_data_irq); > + if (ret < 0) > + goto err; > + > + ret = sun4i_irq_init(pdev, "FIFO_DATA_PENDING", > + sun4i_gpadc_fifo_data_irq_handler, "fifo_data", > + &info->fifo_data_irq, &info->ignore_fifo_data_irq); > + if (ret < 0) > + goto err; > + > + ret = iio_map_array_register(indio_dev, sun4i_gpadc_hwmon_maps); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to register iio map array\n"); > + goto err; > + } > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(&pdev->dev, "could not register the device\n"); > + goto err_map; > + } > + > + return 0; > + > +err_map: > + iio_map_array_unregister(indio_dev); > + > +err: > + pm_runtime_put(&pdev->dev); > + pm_runtime_disable(&pdev->dev); > + > + return ret; > +} > + > +static int sun4i_gpadc_remove(struct platform_device *pdev) > +{ > + struct sun4i_gpadc_iio *info; > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + > + pm_runtime_put(&pdev->dev); > + pm_runtime_disable(&pdev->dev); > + info = iio_priv(indio_dev); > + iio_map_array_unregister(indio_dev); > + iio_device_unregister(indio_dev); > + > + return 0; > +} > + > +static const struct platform_device_id sun4i_gpadc_id[] = { > + { "sun4i-a10-gpadc-iio", (kernel_ulong_t)&sun4i_gpadc_data }, > + { "sun5i-a13-gpadc-iio", (kernel_ulong_t)&sun5i_gpadc_data }, > + { "sun6i-a31-gpadc-iio", (kernel_ulong_t)&sun6i_gpadc_data }, > + { /* sentinel */ }, > +}; > + > +static struct platform_driver sun4i_gpadc_driver = { > + .driver = { > + .name = "sun4i-gpadc-iio", > + .pm = &sun4i_gpadc_pm_ops, > + }, > + .id_table = sun4i_gpadc_id, > + .probe = sun4i_gpadc_probe, > + .remove = sun4i_gpadc_remove, > +}; > + > +module_platform_driver(sun4i_gpadc_driver); > + > +MODULE_DESCRIPTION("ADC driver for sunxi platforms"); > +MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>"); > +MODULE_LICENSE("GPL v2"); >
Hi Jonathan and Lee, On 30/10/2016 17:59, Jonathan Cameron wrote: > On 15/09/16 13:44, Quentin Schulz wrote: >> The Allwinner SoCs all have an ADC that can also act as a touchscreen >> controller and a thermal sensor. This patch adds the ADC driver which is >> based on the MFD for the same SoCs ADC. >> >> This also registers the thermal adc channel in the iio map array so >> iio_hwmon could use it without modifying the Device Tree. This registers >> the driver in the thermal framework. >> >> This driver probes on three different platform_device_id to take into >> account slight differences (registers bit and temperature computation) >> between Allwinner SoCs ADCs. >> >> Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> >> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> >> Acked-by: Jonathan Cameron <jic23@kernel.org> > Hi Lee, > > As you applied the MFD part of this series, could you pick this up as well? > Someone reported some bugs on the CHIP (sun5i-r8). I'm investigating that. Also, it misses a scale for voltage (not that critical but still). And also, Thomas Petazzoni just found a deadlock in sun4i_gpadc_read. If a regmap_write fails after getting the mutex, it is never released. Is there some sort of deadline you want for a v7 since the mfd patch has been merged? Thanks, Quentin > Thanks, > > Jonathan >> --- >> >> v6: >> - remove useless member (regs) from sun4i_gpadc_dev structure, >> - rename sun4i_gpadc_dev structure to sun4i_gpadc_iio, >> - remove regmap_update_bits used to disable hardware interrupts, it is already >> handled by devm functions, >> >> v5: >> - correct mail address, >> - correct several typos, >> - move from const to static for sunxi_gpadc_chan_select functions, >> - rename soc_specific struct to gpadc_data, >> - rename soc_specific field to data in sun4i_gpadc_dev, >> - return error code from regmap_write in case of failure in read_raws, >> - share if condition in IIO_CHAN_INFO_RAW case, >> - add comment on why we use parent device for registering in thermal, >> - reordering remove function, >> >> v4: >> - rename files and variables from sunxi* to sun4i*, >> - shorten sunxi_gpadc_soc_specific structure to soc_specific, >> - factorize sysfs ADC and temp read_raws, >> - use cached values when read_raw times out (except before a first value >> is gotten), >> - remove mutex locks and unlocks from runtime_pm functions, >> - factorize irq initializations, >> - initialize temp_data and fifo_data values to -1 (error value), >> - "impersonate" MFD to register in thermal framework, >> - deactivate hardware interrupts one by one when probe fails or when >> removing driver instead of blindly deactivating all hardware interrupts, >> - selects THERMAL_OF in Kconfig, >> >> v3: >> - correct wrapping, >> - add comment about thermal sensor inner working, >> - move defines in mfd header, >> - use structure to define SoC specific registers or behaviour, >> - attach this structure to the device according to of_device_id of the >> platform device, >> - use new mutex instead of iio_dev mutex, >> - use atomic flags to avoid race between request_irq and disable_irq in >> probe, >> - switch from processed value to raw, offset and scale values for >> temperature ADC channel, >> - remove faulty sentinel in iio_chan_spec array, >> - add pm_runtime support, >> - register thermal sensor in thermal framework (forgotten since the >> beginning whereas it is present in current sun4i-ts driver), >> - remove useless ret variables to store return value of regmap_reads, >> - move comments on thermal sensor acquisition period in code instead of >> header, >> - adding goto label to unregister iio_map_array when failing to register >> iio_dev, >> >> v2: >> - add SUNXI_GPADC_ prefixes for defines, >> - correct typo in Kconfig, >> - reorder alphabetically includes, makefile, >> - add license header, >> - fix architecture variations not being handled in interrupt handlers or >> read raw functions, >> - fix unability to return negative values from thermal sensor, >> - add gotos to reduce code repetition, >> - fix irq variable being unsigned int instead of int, >> - remove useless dev_err and dev_info, >> - deactivate all interrupts if probe fails, >> - fix iio_device_register on NULL variable, >> - deactivate ADC in the IP when probe fails or when removing driver, >> >> drivers/iio/adc/Kconfig | 13 + >> drivers/iio/adc/Makefile | 1 + >> drivers/iio/adc/sun4i-gpadc-iio.c | 522 ++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 536 insertions(+) >> create mode 100644 drivers/iio/adc/sun4i-gpadc-iio.c >> >> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >> index 25378c5..ea36a4f 100644 >> --- a/drivers/iio/adc/Kconfig >> +++ b/drivers/iio/adc/Kconfig >> @@ -384,6 +384,19 @@ config ROCKCHIP_SARADC >> To compile this driver as a module, choose M here: the >> module will be called rockchip_saradc. >> >> +config SUN4I_GPADC >> + tristate "Support for the Allwinner SoCs GPADC" >> + depends on IIO >> + depends on MFD_SUN4I_GPADC >> + select THERMAL_OF >> + help >> + Say yes here to build support for Allwinner (A10, A13 and A31) SoCs >> + GPADC. This ADC provides 4 channels which can be used as an ADC or as >> + a touchscreen input and one channel for thermal sensor. >> + >> + To compile this driver as a module, choose M here: the module will be >> + called sun4i-gpadc-iio. >> + >> config TI_ADC081C >> tristate "Texas Instruments ADC081C/ADC101C/ADC121C family" >> depends on I2C >> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile >> index 38638d4..204372d 100644 >> --- a/drivers/iio/adc/Makefile >> +++ b/drivers/iio/adc/Makefile >> @@ -37,6 +37,7 @@ obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o >> obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o >> obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o >> obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o >> +obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o >> obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o >> obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o >> obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o >> diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c >> new file mode 100644 >> index 0000000..e2c5ba8 >> --- /dev/null >> +++ b/drivers/iio/adc/sun4i-gpadc-iio.c >> @@ -0,0 +1,522 @@ >> +/* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC >> + * >> + * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com> >> + * >> + * This program is free software; you can redistribute it and/or modify it under >> + * the terms of the GNU General Public License version 2 as published by the >> + * Free Software Foundation. >> + * >> + * The Allwinner SoCs all have an ADC that can also act as a touchscreen >> + * controller and a thermal sensor. >> + * The thermal sensor works only when the ADC acts as a touchscreen controller >> + * and is configured to throw an interrupt every fixed periods of time (let say >> + * every X seconds). >> + * One would be tempted to disable the IP on the hardware side rather than >> + * disabling interrupts to save some power but that resets the internal clock of >> + * the IP, resulting in having to wait X seconds every time we want to read the >> + * value of the thermal sensor. >> + * This is also the reason of using autosuspend in pm_runtime. If there was no >> + * autosuspend, the thermal sensor would need X seconds after every >> + * pm_runtime_get_sync to get a value from the ADC. The autosuspend allows the >> + * thermal sensor to be requested again in a certain time span before it gets >> + * shutdown for not being used. >> + */ >> + >> +#include <linux/completion.h> >> +#include <linux/interrupt.h> >> +#include <linux/io.h> >> +#include <linux/module.h> >> +#include <linux/of.h> >> +#include <linux/of_device.h> >> +#include <linux/platform_device.h> >> +#include <linux/pm_runtime.h> >> +#include <linux/regmap.h> >> +#include <linux/thermal.h> >> + >> +#include <linux/iio/iio.h> >> +#include <linux/iio/driver.h> >> +#include <linux/iio/machine.h> >> +#include <linux/mfd/sun4i-gpadc.h> >> + >> +static unsigned int sun4i_gpadc_chan_select(unsigned int chan) >> +{ >> + return SUN4I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); >> +} >> + >> +static unsigned int sun6i_gpadc_chan_select(unsigned int chan) >> +{ >> + return SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); >> +} >> + >> +struct gpadc_data { >> + int temp_offset; >> + int temp_scale; >> + unsigned int tp_mode_en; >> + unsigned int tp_adc_select; >> + unsigned int (*adc_chan_select)(unsigned int chan); >> +}; >> + >> +static const struct gpadc_data sun4i_gpadc_data = { >> + .temp_offset = -1932, >> + .temp_scale = 133, >> + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, >> + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, >> + .adc_chan_select = &sun4i_gpadc_chan_select, >> +}; >> + >> +static const struct gpadc_data sun5i_gpadc_data = { >> + .temp_offset = -1447, >> + .temp_scale = 100, >> + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, >> + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, >> + .adc_chan_select = &sun4i_gpadc_chan_select, >> +}; >> + >> +static const struct gpadc_data sun6i_gpadc_data = { >> + .temp_offset = -1623, >> + .temp_scale = 167, >> + .tp_mode_en = SUN6I_GPADC_CTRL1_TP_MODE_EN, >> + .tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT, >> + .adc_chan_select = &sun6i_gpadc_chan_select, >> +}; >> + >> +struct sun4i_gpadc_iio { >> + struct iio_dev *indio_dev; >> + struct completion completion; >> + int temp_data; >> + u32 adc_data; >> + struct regmap *regmap; >> + unsigned int fifo_data_irq; >> + atomic_t ignore_fifo_data_irq; >> + unsigned int temp_data_irq; >> + atomic_t ignore_temp_data_irq; >> + const struct gpadc_data *data; >> + /* prevents concurrent reads of temperature and ADC */ >> + struct mutex mutex; >> +}; >> + >> +#define SUN4I_GPADC_ADC_CHANNEL(_channel, _name) { \ >> + .type = IIO_VOLTAGE, \ >> + .indexed = 1, \ >> + .channel = _channel, \ >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ >> + .datasheet_name = _name, \ >> +} >> + >> +static struct iio_map sun4i_gpadc_hwmon_maps[] = { >> + { >> + .adc_channel_label = "temp_adc", >> + .consumer_dev_name = "iio_hwmon.0", >> + }, >> + { /* sentinel */ }, >> +}; >> + >> +static const struct iio_chan_spec sun4i_gpadc_channels[] = { >> + SUN4I_GPADC_ADC_CHANNEL(0, "adc_chan0"), >> + SUN4I_GPADC_ADC_CHANNEL(1, "adc_chan1"), >> + SUN4I_GPADC_ADC_CHANNEL(2, "adc_chan2"), >> + SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"), >> + { >> + .type = IIO_TEMP, >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | >> + BIT(IIO_CHAN_INFO_SCALE) | >> + BIT(IIO_CHAN_INFO_OFFSET), >> + .datasheet_name = "temp_adc", >> + }, >> +}; >> + >> +static int sun4i_gpadc_read(struct iio_dev *indio_dev, int channel, int *val, >> + unsigned int irq) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >> + int ret = 0; >> + >> + pm_runtime_get_sync(indio_dev->dev.parent); >> + mutex_lock(&info->mutex); >> + >> + reinit_completion(&info->completion); >> + >> + ret = regmap_write(info->regmap, SUN4I_GPADC_INT_FIFOC, >> + SUN4I_GPADC_INT_FIFOC_TP_FIFO_TRIG_LEVEL(1) | >> + SUN4I_GPADC_INT_FIFOC_TP_FIFO_FLUSH); >> + if (ret) >> + return ret; >> + >> + if (irq == info->fifo_data_irq) { >> + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, >> + info->data->tp_mode_en | >> + info->data->tp_adc_select | >> + info->data->adc_chan_select(channel)); >> + } else { >> + /* >> + * The temperature sensor returns valid data only when the ADC >> + * operates in touchscreen mode. >> + */ >> + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, >> + info->data->tp_mode_en); >> + } >> + >> + if (ret) >> + return ret; >> + >> + enable_irq(irq); >> + >> + if (!wait_for_completion_timeout(&info->completion, >> + msecs_to_jiffies(100))) { >> + if ((irq == info->fifo_data_irq && info->adc_data == -1) || >> + (irq == info->temp_data_irq && info->temp_data == -1)) { >> + ret = -ETIMEDOUT; >> + goto out; >> + } >> + } >> + >> + if (irq == info->fifo_data_irq) >> + *val = info->adc_data; >> + else >> + *val = info->temp_data; >> + >> + ret = 0; >> + >> +out: >> + disable_irq(irq); >> + mutex_unlock(&info->mutex); >> + pm_runtime_mark_last_busy(indio_dev->dev.parent); >> + pm_runtime_put_autosuspend(indio_dev->dev.parent); >> + >> + return ret; >> +} >> + >> +static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel, >> + int *val) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >> + >> + return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq); >> +} >> + >> +static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >> + >> + return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq); >> +} >> + >> +static int sun4i_gpadc_temp_offset(struct iio_dev *indio_dev, int *val) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >> + >> + *val = info->data->temp_offset; >> + >> + return 0; >> +} >> + >> +static int sun4i_gpadc_temp_scale(struct iio_dev *indio_dev, int *val) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >> + >> + *val = info->data->temp_scale; >> + >> + return 0; >> +} >> + >> +static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev, >> + struct iio_chan_spec const *chan, int *val, >> + int *val2, long mask) >> +{ >> + int ret; >> + >> + switch (mask) { >> + case IIO_CHAN_INFO_OFFSET: >> + ret = sun4i_gpadc_temp_offset(indio_dev, val); >> + if (ret) >> + return ret; >> + >> + return IIO_VAL_INT; >> + case IIO_CHAN_INFO_RAW: >> + if (chan->type == IIO_VOLTAGE) >> + ret = sun4i_gpadc_adc_read(indio_dev, chan->channel, >> + val); >> + else >> + ret = sun4i_gpadc_temp_read(indio_dev, val); >> + >> + if (ret) >> + return ret; >> + >> + return IIO_VAL_INT; >> + case IIO_CHAN_INFO_SCALE: >> + ret = sun4i_gpadc_temp_scale(indio_dev, val); >> + if (ret) >> + return ret; >> + >> + return IIO_VAL_INT; >> + default: >> + return -EINVAL; >> + } >> + >> + return -EINVAL; >> +} >> + >> +static const struct iio_info sun4i_gpadc_iio_info = { >> + .read_raw = sun4i_gpadc_read_raw, >> + .driver_module = THIS_MODULE, >> +}; >> + >> +static irqreturn_t sun4i_gpadc_temp_data_irq_handler(int irq, void *dev_id) >> +{ >> + struct sun4i_gpadc_iio *info = dev_id; >> + >> + if (atomic_read(&info->ignore_temp_data_irq)) >> + return IRQ_HANDLED; >> + >> + if (!regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, &info->temp_data)) >> + complete(&info->completion); >> + >> + return IRQ_HANDLED; >> +} >> + >> +static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id) >> +{ >> + struct sun4i_gpadc_iio *info = dev_id; >> + >> + if (atomic_read(&info->ignore_fifo_data_irq)) >> + return IRQ_HANDLED; >> + >> + if (!regmap_read(info->regmap, SUN4I_GPADC_DATA, &info->adc_data)) >> + complete(&info->completion); >> + >> + return IRQ_HANDLED; >> +} >> + >> +static int sun4i_gpadc_runtime_suspend(struct device *dev) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); >> + >> + /* Disable the ADC on IP */ >> + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, 0); >> + /* Disable temperature sensor on IP */ >> + regmap_write(info->regmap, SUN4I_GPADC_TPR, 0); >> + >> + return 0; >> +} >> + >> +static int sun4i_gpadc_runtime_resume(struct device *dev) >> +{ >> + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); >> + >> + /* clkin = 6MHz */ >> + regmap_write(info->regmap, SUN4I_GPADC_CTRL0, >> + SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(2) | >> + SUN4I_GPADC_CTRL0_FS_DIV(7) | >> + SUN4I_GPADC_CTRL0_T_ACQ(63)); >> + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, info->data->tp_mode_en); >> + regmap_write(info->regmap, SUN4I_GPADC_CTRL3, >> + SUN4I_GPADC_CTRL3_FILTER_EN | >> + SUN4I_GPADC_CTRL3_FILTER_TYPE(1)); >> + /* period = SUN4I_GPADC_TPR_TEMP_PERIOD * 256 * 16 / clkin; ~1.3s */ >> + regmap_write(info->regmap, SUN4I_GPADC_TPR, >> + SUN4I_GPADC_TPR_TEMP_ENABLE | >> + SUN4I_GPADC_TPR_TEMP_PERIOD(1953)); >> + >> + return 0; >> +} >> + >> +static int sun4i_gpadc_get_temp(void *data, int *temp) >> +{ >> + struct sun4i_gpadc_iio *info = (struct sun4i_gpadc_iio *)data; >> + int val, scale, offset; >> + >> + /* If reading temperature times out, take stored previous value. */ >> + if (sun4i_gpadc_temp_read(info->indio_dev, &val)) >> + val = info->temp_data; >> + sun4i_gpadc_temp_scale(info->indio_dev, &scale); >> + sun4i_gpadc_temp_offset(info->indio_dev, &offset); >> + >> + *temp = (val + offset) * scale; >> + >> + return 0; >> +} >> + >> +static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { >> + .get_temp = &sun4i_gpadc_get_temp, >> +}; >> + >> +static const struct dev_pm_ops sun4i_gpadc_pm_ops = { >> + .runtime_suspend = &sun4i_gpadc_runtime_suspend, >> + .runtime_resume = &sun4i_gpadc_runtime_resume, >> +}; >> + >> +static int sun4i_irq_init(struct platform_device *pdev, const char *name, >> + irq_handler_t handler, const char *devname, >> + unsigned int *irq, atomic_t *atomic) >> +{ >> + int ret; >> + struct sun4i_gpadc_dev *mfd_dev = dev_get_drvdata(pdev->dev.parent); >> + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(&pdev->dev)); >> + >> + /* >> + * Once the interrupt is activated, the IP continuously performs >> + * conversions thus throws interrupts. The interrupt is activated right >> + * after being requested but we want to control when these interrupts >> + * occur thus we disable it right after being requested. However, an >> + * interrupt might occur between these two instructions and we have to >> + * make sure that does not happen, by using atomic flags. We set the >> + * flag before requesting the interrupt and unset it right after >> + * disabling the interrupt. When an interrupt occurs between these two >> + * instructions, reading the atomic flag will tell us to ignore the >> + * interrupt. >> + */ >> + atomic_set(atomic, 1); >> + >> + *irq = platform_get_irq_byname(pdev, name); >> + if (*irq < 0) { >> + dev_err(&pdev->dev, "no %s interrupt registered\n", name); >> + return *irq; >> + } >> + >> + *irq = regmap_irq_get_virq(mfd_dev->regmap_irqc, *irq); >> + ret = devm_request_any_context_irq(&pdev->dev, *irq, handler, 0, >> + devname, info); >> + if (ret < 0) { >> + dev_err(&pdev->dev, "could not request %s interrupt: %d\n", >> + name, ret); >> + return ret; >> + } >> + >> + disable_irq(*irq); >> + atomic_set(atomic, 0); >> + >> + return 0; >> +} >> + >> +static int sun4i_gpadc_probe(struct platform_device *pdev) >> +{ >> + struct sun4i_gpadc_iio *info; >> + struct iio_dev *indio_dev; >> + int ret; >> + struct sun4i_gpadc_dev *sun4i_gpadc_dev; >> + struct thermal_zone_device *tzd; >> + >> + sun4i_gpadc_dev = dev_get_drvdata(pdev->dev.parent); >> + >> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); >> + if (!indio_dev) >> + return -ENOMEM; >> + >> + info = iio_priv(indio_dev); >> + platform_set_drvdata(pdev, indio_dev); >> + >> + mutex_init(&info->mutex); >> + info->regmap = sun4i_gpadc_dev->regmap; >> + info->indio_dev = indio_dev; >> + info->temp_data = -1; >> + info->adc_data = -1; >> + init_completion(&info->completion); >> + 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 = &sun4i_gpadc_iio_info; >> + indio_dev->modes = INDIO_DIRECT_MODE; >> + indio_dev->num_channels = ARRAY_SIZE(sun4i_gpadc_channels); >> + indio_dev->channels = sun4i_gpadc_channels; >> + >> + info->data = (struct gpadc_data *)platform_get_device_id(pdev)->driver_data; >> + >> + /* >> + * This driver is a child of an MFD which has a node in the DT but not >> + * its children. Therefore, the resulting devices of this driver do not >> + * have an of_node variable. >> + * However, its parent (the MFD driver) has an of_node variable and >> + * since devm_thermal_zone_of_sensor_register uses its first argument to >> + * match the phandle defined in the node of the thermal driver with the >> + * of_node of the device passed as first argument and the third argument >> + * to call ops from thermal_zone_of_device_ops, the solution is to use >> + * the parent device as first argument to match the phandle with its >> + * of_node, and the device from this driver as third argument to return >> + * the temperature. >> + */ >> + tzd = devm_thermal_zone_of_sensor_register(pdev->dev.parent, 0, info, >> + &sun4i_ts_tz_ops); >> + if (IS_ERR(tzd)) { >> + dev_err(&pdev->dev, "could not register thermal sensor: %ld\n", >> + PTR_ERR(tzd)); >> + return PTR_ERR(tzd); >> + } >> + >> + pm_runtime_set_autosuspend_delay(&pdev->dev, >> + SUN4I_GPADC_AUTOSUSPEND_DELAY); >> + pm_runtime_use_autosuspend(&pdev->dev); >> + pm_runtime_set_suspended(&pdev->dev); >> + pm_runtime_enable(&pdev->dev); >> + >> + ret = sun4i_irq_init(pdev, "TEMP_DATA_PENDING", >> + sun4i_gpadc_temp_data_irq_handler, "temp_data", >> + &info->temp_data_irq, &info->ignore_temp_data_irq); >> + if (ret < 0) >> + goto err; >> + >> + ret = sun4i_irq_init(pdev, "FIFO_DATA_PENDING", >> + sun4i_gpadc_fifo_data_irq_handler, "fifo_data", >> + &info->fifo_data_irq, &info->ignore_fifo_data_irq); >> + if (ret < 0) >> + goto err; >> + >> + ret = iio_map_array_register(indio_dev, sun4i_gpadc_hwmon_maps); >> + if (ret < 0) { >> + dev_err(&pdev->dev, "failed to register iio map array\n"); >> + goto err; >> + } >> + >> + ret = iio_device_register(indio_dev); >> + if (ret < 0) { >> + dev_err(&pdev->dev, "could not register the device\n"); >> + goto err_map; >> + } >> + >> + return 0; >> + >> +err_map: >> + iio_map_array_unregister(indio_dev); >> + >> +err: >> + pm_runtime_put(&pdev->dev); >> + pm_runtime_disable(&pdev->dev); >> + >> + return ret; >> +} >> + >> +static int sun4i_gpadc_remove(struct platform_device *pdev) >> +{ >> + struct sun4i_gpadc_iio *info; >> + struct iio_dev *indio_dev = platform_get_drvdata(pdev); >> + >> + pm_runtime_put(&pdev->dev); >> + pm_runtime_disable(&pdev->dev); >> + info = iio_priv(indio_dev); >> + iio_map_array_unregister(indio_dev); >> + iio_device_unregister(indio_dev); >> + >> + return 0; >> +} >> + >> +static const struct platform_device_id sun4i_gpadc_id[] = { >> + { "sun4i-a10-gpadc-iio", (kernel_ulong_t)&sun4i_gpadc_data }, >> + { "sun5i-a13-gpadc-iio", (kernel_ulong_t)&sun5i_gpadc_data }, >> + { "sun6i-a31-gpadc-iio", (kernel_ulong_t)&sun6i_gpadc_data }, >> + { /* sentinel */ }, >> +}; >> + >> +static struct platform_driver sun4i_gpadc_driver = { >> + .driver = { >> + .name = "sun4i-gpadc-iio", >> + .pm = &sun4i_gpadc_pm_ops, >> + }, >> + .id_table = sun4i_gpadc_id, >> + .probe = sun4i_gpadc_probe, >> + .remove = sun4i_gpadc_remove, >> +}; >> + >> +module_platform_driver(sun4i_gpadc_driver); >> + >> +MODULE_DESCRIPTION("ADC driver for sunxi platforms"); >> +MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>"); >> +MODULE_LICENSE("GPL v2"); >> >
On 31/10/16 09:34, Quentin Schulz wrote: > Hi Jonathan and Lee, > > On 30/10/2016 17:59, Jonathan Cameron wrote: >> On 15/09/16 13:44, Quentin Schulz wrote: >>> The Allwinner SoCs all have an ADC that can also act as a touchscreen >>> controller and a thermal sensor. This patch adds the ADC driver which is >>> based on the MFD for the same SoCs ADC. >>> >>> This also registers the thermal adc channel in the iio map array so >>> iio_hwmon could use it without modifying the Device Tree. This registers >>> the driver in the thermal framework. >>> >>> This driver probes on three different platform_device_id to take into >>> account slight differences (registers bit and temperature computation) >>> between Allwinner SoCs ADCs. >>> >>> Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> >>> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> >>> Acked-by: Jonathan Cameron <jic23@kernel.org> >> Hi Lee, >> >> As you applied the MFD part of this series, could you pick this up as well? >> > > Someone reported some bugs on the CHIP (sun5i-r8). I'm investigating that. > > Also, it misses a scale for voltage (not that critical but still). > > And also, Thomas Petazzoni just found a deadlock in sun4i_gpadc_read. If > a regmap_write fails after getting the mutex, it is never released. > > Is there some sort of deadline you want for a v7 since the mfd patch has > been merged? > No rush at all. Doesn't matter as long as we know it's on it's way sooner or later. If it falls into the next cycle, that's fine - I'll just pick it up directly as dependencies will in place by then. Jonathan > Thanks, > Quentin > >> Thanks, >> >> Jonathan >>> --- >>> >>> v6: >>> - remove useless member (regs) from sun4i_gpadc_dev structure, >>> - rename sun4i_gpadc_dev structure to sun4i_gpadc_iio, >>> - remove regmap_update_bits used to disable hardware interrupts, it is already >>> handled by devm functions, >>> >>> v5: >>> - correct mail address, >>> - correct several typos, >>> - move from const to static for sunxi_gpadc_chan_select functions, >>> - rename soc_specific struct to gpadc_data, >>> - rename soc_specific field to data in sun4i_gpadc_dev, >>> - return error code from regmap_write in case of failure in read_raws, >>> - share if condition in IIO_CHAN_INFO_RAW case, >>> - add comment on why we use parent device for registering in thermal, >>> - reordering remove function, >>> >>> v4: >>> - rename files and variables from sunxi* to sun4i*, >>> - shorten sunxi_gpadc_soc_specific structure to soc_specific, >>> - factorize sysfs ADC and temp read_raws, >>> - use cached values when read_raw times out (except before a first value >>> is gotten), >>> - remove mutex locks and unlocks from runtime_pm functions, >>> - factorize irq initializations, >>> - initialize temp_data and fifo_data values to -1 (error value), >>> - "impersonate" MFD to register in thermal framework, >>> - deactivate hardware interrupts one by one when probe fails or when >>> removing driver instead of blindly deactivating all hardware interrupts, >>> - selects THERMAL_OF in Kconfig, >>> >>> v3: >>> - correct wrapping, >>> - add comment about thermal sensor inner working, >>> - move defines in mfd header, >>> - use structure to define SoC specific registers or behaviour, >>> - attach this structure to the device according to of_device_id of the >>> platform device, >>> - use new mutex instead of iio_dev mutex, >>> - use atomic flags to avoid race between request_irq and disable_irq in >>> probe, >>> - switch from processed value to raw, offset and scale values for >>> temperature ADC channel, >>> - remove faulty sentinel in iio_chan_spec array, >>> - add pm_runtime support, >>> - register thermal sensor in thermal framework (forgotten since the >>> beginning whereas it is present in current sun4i-ts driver), >>> - remove useless ret variables to store return value of regmap_reads, >>> - move comments on thermal sensor acquisition period in code instead of >>> header, >>> - adding goto label to unregister iio_map_array when failing to register >>> iio_dev, >>> >>> v2: >>> - add SUNXI_GPADC_ prefixes for defines, >>> - correct typo in Kconfig, >>> - reorder alphabetically includes, makefile, >>> - add license header, >>> - fix architecture variations not being handled in interrupt handlers or >>> read raw functions, >>> - fix unability to return negative values from thermal sensor, >>> - add gotos to reduce code repetition, >>> - fix irq variable being unsigned int instead of int, >>> - remove useless dev_err and dev_info, >>> - deactivate all interrupts if probe fails, >>> - fix iio_device_register on NULL variable, >>> - deactivate ADC in the IP when probe fails or when removing driver, >>> >>> drivers/iio/adc/Kconfig | 13 + >>> drivers/iio/adc/Makefile | 1 + >>> drivers/iio/adc/sun4i-gpadc-iio.c | 522 ++++++++++++++++++++++++++++++++++++++ >>> 3 files changed, 536 insertions(+) >>> create mode 100644 drivers/iio/adc/sun4i-gpadc-iio.c >>> >>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >>> index 25378c5..ea36a4f 100644 >>> --- a/drivers/iio/adc/Kconfig >>> +++ b/drivers/iio/adc/Kconfig >>> @@ -384,6 +384,19 @@ config ROCKCHIP_SARADC >>> To compile this driver as a module, choose M here: the >>> module will be called rockchip_saradc. >>> >>> +config SUN4I_GPADC >>> + tristate "Support for the Allwinner SoCs GPADC" >>> + depends on IIO >>> + depends on MFD_SUN4I_GPADC >>> + select THERMAL_OF >>> + help >>> + Say yes here to build support for Allwinner (A10, A13 and A31) SoCs >>> + GPADC. This ADC provides 4 channels which can be used as an ADC or as >>> + a touchscreen input and one channel for thermal sensor. >>> + >>> + To compile this driver as a module, choose M here: the module will be >>> + called sun4i-gpadc-iio. >>> + >>> config TI_ADC081C >>> tristate "Texas Instruments ADC081C/ADC101C/ADC121C family" >>> depends on I2C >>> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile >>> index 38638d4..204372d 100644 >>> --- a/drivers/iio/adc/Makefile >>> +++ b/drivers/iio/adc/Makefile >>> @@ -37,6 +37,7 @@ obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o >>> obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o >>> obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o >>> obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o >>> +obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o >>> obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o >>> obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o >>> obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o >>> diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c >>> new file mode 100644 >>> index 0000000..e2c5ba8 >>> --- /dev/null >>> +++ b/drivers/iio/adc/sun4i-gpadc-iio.c >>> @@ -0,0 +1,522 @@ >>> +/* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC >>> + * >>> + * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com> >>> + * >>> + * This program is free software; you can redistribute it and/or modify it under >>> + * the terms of the GNU General Public License version 2 as published by the >>> + * Free Software Foundation. >>> + * >>> + * The Allwinner SoCs all have an ADC that can also act as a touchscreen >>> + * controller and a thermal sensor. >>> + * The thermal sensor works only when the ADC acts as a touchscreen controller >>> + * and is configured to throw an interrupt every fixed periods of time (let say >>> + * every X seconds). >>> + * One would be tempted to disable the IP on the hardware side rather than >>> + * disabling interrupts to save some power but that resets the internal clock of >>> + * the IP, resulting in having to wait X seconds every time we want to read the >>> + * value of the thermal sensor. >>> + * This is also the reason of using autosuspend in pm_runtime. If there was no >>> + * autosuspend, the thermal sensor would need X seconds after every >>> + * pm_runtime_get_sync to get a value from the ADC. The autosuspend allows the >>> + * thermal sensor to be requested again in a certain time span before it gets >>> + * shutdown for not being used. >>> + */ >>> + >>> +#include <linux/completion.h> >>> +#include <linux/interrupt.h> >>> +#include <linux/io.h> >>> +#include <linux/module.h> >>> +#include <linux/of.h> >>> +#include <linux/of_device.h> >>> +#include <linux/platform_device.h> >>> +#include <linux/pm_runtime.h> >>> +#include <linux/regmap.h> >>> +#include <linux/thermal.h> >>> + >>> +#include <linux/iio/iio.h> >>> +#include <linux/iio/driver.h> >>> +#include <linux/iio/machine.h> >>> +#include <linux/mfd/sun4i-gpadc.h> >>> + >>> +static unsigned int sun4i_gpadc_chan_select(unsigned int chan) >>> +{ >>> + return SUN4I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); >>> +} >>> + >>> +static unsigned int sun6i_gpadc_chan_select(unsigned int chan) >>> +{ >>> + return SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); >>> +} >>> + >>> +struct gpadc_data { >>> + int temp_offset; >>> + int temp_scale; >>> + unsigned int tp_mode_en; >>> + unsigned int tp_adc_select; >>> + unsigned int (*adc_chan_select)(unsigned int chan); >>> +}; >>> + >>> +static const struct gpadc_data sun4i_gpadc_data = { >>> + .temp_offset = -1932, >>> + .temp_scale = 133, >>> + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, >>> + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, >>> + .adc_chan_select = &sun4i_gpadc_chan_select, >>> +}; >>> + >>> +static const struct gpadc_data sun5i_gpadc_data = { >>> + .temp_offset = -1447, >>> + .temp_scale = 100, >>> + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, >>> + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, >>> + .adc_chan_select = &sun4i_gpadc_chan_select, >>> +}; >>> + >>> +static const struct gpadc_data sun6i_gpadc_data = { >>> + .temp_offset = -1623, >>> + .temp_scale = 167, >>> + .tp_mode_en = SUN6I_GPADC_CTRL1_TP_MODE_EN, >>> + .tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT, >>> + .adc_chan_select = &sun6i_gpadc_chan_select, >>> +}; >>> + >>> +struct sun4i_gpadc_iio { >>> + struct iio_dev *indio_dev; >>> + struct completion completion; >>> + int temp_data; >>> + u32 adc_data; >>> + struct regmap *regmap; >>> + unsigned int fifo_data_irq; >>> + atomic_t ignore_fifo_data_irq; >>> + unsigned int temp_data_irq; >>> + atomic_t ignore_temp_data_irq; >>> + const struct gpadc_data *data; >>> + /* prevents concurrent reads of temperature and ADC */ >>> + struct mutex mutex; >>> +}; >>> + >>> +#define SUN4I_GPADC_ADC_CHANNEL(_channel, _name) { \ >>> + .type = IIO_VOLTAGE, \ >>> + .indexed = 1, \ >>> + .channel = _channel, \ >>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ >>> + .datasheet_name = _name, \ >>> +} >>> + >>> +static struct iio_map sun4i_gpadc_hwmon_maps[] = { >>> + { >>> + .adc_channel_label = "temp_adc", >>> + .consumer_dev_name = "iio_hwmon.0", >>> + }, >>> + { /* sentinel */ }, >>> +}; >>> + >>> +static const struct iio_chan_spec sun4i_gpadc_channels[] = { >>> + SUN4I_GPADC_ADC_CHANNEL(0, "adc_chan0"), >>> + SUN4I_GPADC_ADC_CHANNEL(1, "adc_chan1"), >>> + SUN4I_GPADC_ADC_CHANNEL(2, "adc_chan2"), >>> + SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"), >>> + { >>> + .type = IIO_TEMP, >>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | >>> + BIT(IIO_CHAN_INFO_SCALE) | >>> + BIT(IIO_CHAN_INFO_OFFSET), >>> + .datasheet_name = "temp_adc", >>> + }, >>> +}; >>> + >>> +static int sun4i_gpadc_read(struct iio_dev *indio_dev, int channel, int *val, >>> + unsigned int irq) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >>> + int ret = 0; >>> + >>> + pm_runtime_get_sync(indio_dev->dev.parent); >>> + mutex_lock(&info->mutex); >>> + >>> + reinit_completion(&info->completion); >>> + >>> + ret = regmap_write(info->regmap, SUN4I_GPADC_INT_FIFOC, >>> + SUN4I_GPADC_INT_FIFOC_TP_FIFO_TRIG_LEVEL(1) | >>> + SUN4I_GPADC_INT_FIFOC_TP_FIFO_FLUSH); >>> + if (ret) >>> + return ret; >>> + >>> + if (irq == info->fifo_data_irq) { >>> + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, >>> + info->data->tp_mode_en | >>> + info->data->tp_adc_select | >>> + info->data->adc_chan_select(channel)); >>> + } else { >>> + /* >>> + * The temperature sensor returns valid data only when the ADC >>> + * operates in touchscreen mode. >>> + */ >>> + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, >>> + info->data->tp_mode_en); >>> + } >>> + >>> + if (ret) >>> + return ret; >>> + >>> + enable_irq(irq); >>> + >>> + if (!wait_for_completion_timeout(&info->completion, >>> + msecs_to_jiffies(100))) { >>> + if ((irq == info->fifo_data_irq && info->adc_data == -1) || >>> + (irq == info->temp_data_irq && info->temp_data == -1)) { >>> + ret = -ETIMEDOUT; >>> + goto out; >>> + } >>> + } >>> + >>> + if (irq == info->fifo_data_irq) >>> + *val = info->adc_data; >>> + else >>> + *val = info->temp_data; >>> + >>> + ret = 0; >>> + >>> +out: >>> + disable_irq(irq); >>> + mutex_unlock(&info->mutex); >>> + pm_runtime_mark_last_busy(indio_dev->dev.parent); >>> + pm_runtime_put_autosuspend(indio_dev->dev.parent); >>> + >>> + return ret; >>> +} >>> + >>> +static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel, >>> + int *val) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >>> + >>> + return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq); >>> +} >>> + >>> +static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >>> + >>> + return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq); >>> +} >>> + >>> +static int sun4i_gpadc_temp_offset(struct iio_dev *indio_dev, int *val) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >>> + >>> + *val = info->data->temp_offset; >>> + >>> + return 0; >>> +} >>> + >>> +static int sun4i_gpadc_temp_scale(struct iio_dev *indio_dev, int *val) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); >>> + >>> + *val = info->data->temp_scale; >>> + >>> + return 0; >>> +} >>> + >>> +static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev, >>> + struct iio_chan_spec const *chan, int *val, >>> + int *val2, long mask) >>> +{ >>> + int ret; >>> + >>> + switch (mask) { >>> + case IIO_CHAN_INFO_OFFSET: >>> + ret = sun4i_gpadc_temp_offset(indio_dev, val); >>> + if (ret) >>> + return ret; >>> + >>> + return IIO_VAL_INT; >>> + case IIO_CHAN_INFO_RAW: >>> + if (chan->type == IIO_VOLTAGE) >>> + ret = sun4i_gpadc_adc_read(indio_dev, chan->channel, >>> + val); >>> + else >>> + ret = sun4i_gpadc_temp_read(indio_dev, val); >>> + >>> + if (ret) >>> + return ret; >>> + >>> + return IIO_VAL_INT; >>> + case IIO_CHAN_INFO_SCALE: >>> + ret = sun4i_gpadc_temp_scale(indio_dev, val); >>> + if (ret) >>> + return ret; >>> + >>> + return IIO_VAL_INT; >>> + default: >>> + return -EINVAL; >>> + } >>> + >>> + return -EINVAL; >>> +} >>> + >>> +static const struct iio_info sun4i_gpadc_iio_info = { >>> + .read_raw = sun4i_gpadc_read_raw, >>> + .driver_module = THIS_MODULE, >>> +}; >>> + >>> +static irqreturn_t sun4i_gpadc_temp_data_irq_handler(int irq, void *dev_id) >>> +{ >>> + struct sun4i_gpadc_iio *info = dev_id; >>> + >>> + if (atomic_read(&info->ignore_temp_data_irq)) >>> + return IRQ_HANDLED; >>> + >>> + if (!regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, &info->temp_data)) >>> + complete(&info->completion); >>> + >>> + return IRQ_HANDLED; >>> +} >>> + >>> +static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id) >>> +{ >>> + struct sun4i_gpadc_iio *info = dev_id; >>> + >>> + if (atomic_read(&info->ignore_fifo_data_irq)) >>> + return IRQ_HANDLED; >>> + >>> + if (!regmap_read(info->regmap, SUN4I_GPADC_DATA, &info->adc_data)) >>> + complete(&info->completion); >>> + >>> + return IRQ_HANDLED; >>> +} >>> + >>> +static int sun4i_gpadc_runtime_suspend(struct device *dev) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); >>> + >>> + /* Disable the ADC on IP */ >>> + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, 0); >>> + /* Disable temperature sensor on IP */ >>> + regmap_write(info->regmap, SUN4I_GPADC_TPR, 0); >>> + >>> + return 0; >>> +} >>> + >>> +static int sun4i_gpadc_runtime_resume(struct device *dev) >>> +{ >>> + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); >>> + >>> + /* clkin = 6MHz */ >>> + regmap_write(info->regmap, SUN4I_GPADC_CTRL0, >>> + SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(2) | >>> + SUN4I_GPADC_CTRL0_FS_DIV(7) | >>> + SUN4I_GPADC_CTRL0_T_ACQ(63)); >>> + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, info->data->tp_mode_en); >>> + regmap_write(info->regmap, SUN4I_GPADC_CTRL3, >>> + SUN4I_GPADC_CTRL3_FILTER_EN | >>> + SUN4I_GPADC_CTRL3_FILTER_TYPE(1)); >>> + /* period = SUN4I_GPADC_TPR_TEMP_PERIOD * 256 * 16 / clkin; ~1.3s */ >>> + regmap_write(info->regmap, SUN4I_GPADC_TPR, >>> + SUN4I_GPADC_TPR_TEMP_ENABLE | >>> + SUN4I_GPADC_TPR_TEMP_PERIOD(1953)); >>> + >>> + return 0; >>> +} >>> + >>> +static int sun4i_gpadc_get_temp(void *data, int *temp) >>> +{ >>> + struct sun4i_gpadc_iio *info = (struct sun4i_gpadc_iio *)data; >>> + int val, scale, offset; >>> + >>> + /* If reading temperature times out, take stored previous value. */ >>> + if (sun4i_gpadc_temp_read(info->indio_dev, &val)) >>> + val = info->temp_data; >>> + sun4i_gpadc_temp_scale(info->indio_dev, &scale); >>> + sun4i_gpadc_temp_offset(info->indio_dev, &offset); >>> + >>> + *temp = (val + offset) * scale; >>> + >>> + return 0; >>> +} >>> + >>> +static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { >>> + .get_temp = &sun4i_gpadc_get_temp, >>> +}; >>> + >>> +static const struct dev_pm_ops sun4i_gpadc_pm_ops = { >>> + .runtime_suspend = &sun4i_gpadc_runtime_suspend, >>> + .runtime_resume = &sun4i_gpadc_runtime_resume, >>> +}; >>> + >>> +static int sun4i_irq_init(struct platform_device *pdev, const char *name, >>> + irq_handler_t handler, const char *devname, >>> + unsigned int *irq, atomic_t *atomic) >>> +{ >>> + int ret; >>> + struct sun4i_gpadc_dev *mfd_dev = dev_get_drvdata(pdev->dev.parent); >>> + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(&pdev->dev)); >>> + >>> + /* >>> + * Once the interrupt is activated, the IP continuously performs >>> + * conversions thus throws interrupts. The interrupt is activated right >>> + * after being requested but we want to control when these interrupts >>> + * occur thus we disable it right after being requested. However, an >>> + * interrupt might occur between these two instructions and we have to >>> + * make sure that does not happen, by using atomic flags. We set the >>> + * flag before requesting the interrupt and unset it right after >>> + * disabling the interrupt. When an interrupt occurs between these two >>> + * instructions, reading the atomic flag will tell us to ignore the >>> + * interrupt. >>> + */ >>> + atomic_set(atomic, 1); >>> + >>> + *irq = platform_get_irq_byname(pdev, name); >>> + if (*irq < 0) { >>> + dev_err(&pdev->dev, "no %s interrupt registered\n", name); >>> + return *irq; >>> + } >>> + >>> + *irq = regmap_irq_get_virq(mfd_dev->regmap_irqc, *irq); >>> + ret = devm_request_any_context_irq(&pdev->dev, *irq, handler, 0, >>> + devname, info); >>> + if (ret < 0) { >>> + dev_err(&pdev->dev, "could not request %s interrupt: %d\n", >>> + name, ret); >>> + return ret; >>> + } >>> + >>> + disable_irq(*irq); >>> + atomic_set(atomic, 0); >>> + >>> + return 0; >>> +} >>> + >>> +static int sun4i_gpadc_probe(struct platform_device *pdev) >>> +{ >>> + struct sun4i_gpadc_iio *info; >>> + struct iio_dev *indio_dev; >>> + int ret; >>> + struct sun4i_gpadc_dev *sun4i_gpadc_dev; >>> + struct thermal_zone_device *tzd; >>> + >>> + sun4i_gpadc_dev = dev_get_drvdata(pdev->dev.parent); >>> + >>> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); >>> + if (!indio_dev) >>> + return -ENOMEM; >>> + >>> + info = iio_priv(indio_dev); >>> + platform_set_drvdata(pdev, indio_dev); >>> + >>> + mutex_init(&info->mutex); >>> + info->regmap = sun4i_gpadc_dev->regmap; >>> + info->indio_dev = indio_dev; >>> + info->temp_data = -1; >>> + info->adc_data = -1; >>> + init_completion(&info->completion); >>> + 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 = &sun4i_gpadc_iio_info; >>> + indio_dev->modes = INDIO_DIRECT_MODE; >>> + indio_dev->num_channels = ARRAY_SIZE(sun4i_gpadc_channels); >>> + indio_dev->channels = sun4i_gpadc_channels; >>> + >>> + info->data = (struct gpadc_data *)platform_get_device_id(pdev)->driver_data; >>> + >>> + /* >>> + * This driver is a child of an MFD which has a node in the DT but not >>> + * its children. Therefore, the resulting devices of this driver do not >>> + * have an of_node variable. >>> + * However, its parent (the MFD driver) has an of_node variable and >>> + * since devm_thermal_zone_of_sensor_register uses its first argument to >>> + * match the phandle defined in the node of the thermal driver with the >>> + * of_node of the device passed as first argument and the third argument >>> + * to call ops from thermal_zone_of_device_ops, the solution is to use >>> + * the parent device as first argument to match the phandle with its >>> + * of_node, and the device from this driver as third argument to return >>> + * the temperature. >>> + */ >>> + tzd = devm_thermal_zone_of_sensor_register(pdev->dev.parent, 0, info, >>> + &sun4i_ts_tz_ops); >>> + if (IS_ERR(tzd)) { >>> + dev_err(&pdev->dev, "could not register thermal sensor: %ld\n", >>> + PTR_ERR(tzd)); >>> + return PTR_ERR(tzd); >>> + } >>> + >>> + pm_runtime_set_autosuspend_delay(&pdev->dev, >>> + SUN4I_GPADC_AUTOSUSPEND_DELAY); >>> + pm_runtime_use_autosuspend(&pdev->dev); >>> + pm_runtime_set_suspended(&pdev->dev); >>> + pm_runtime_enable(&pdev->dev); >>> + >>> + ret = sun4i_irq_init(pdev, "TEMP_DATA_PENDING", >>> + sun4i_gpadc_temp_data_irq_handler, "temp_data", >>> + &info->temp_data_irq, &info->ignore_temp_data_irq); >>> + if (ret < 0) >>> + goto err; >>> + >>> + ret = sun4i_irq_init(pdev, "FIFO_DATA_PENDING", >>> + sun4i_gpadc_fifo_data_irq_handler, "fifo_data", >>> + &info->fifo_data_irq, &info->ignore_fifo_data_irq); >>> + if (ret < 0) >>> + goto err; >>> + >>> + ret = iio_map_array_register(indio_dev, sun4i_gpadc_hwmon_maps); >>> + if (ret < 0) { >>> + dev_err(&pdev->dev, "failed to register iio map array\n"); >>> + goto err; >>> + } >>> + >>> + ret = iio_device_register(indio_dev); >>> + if (ret < 0) { >>> + dev_err(&pdev->dev, "could not register the device\n"); >>> + goto err_map; >>> + } >>> + >>> + return 0; >>> + >>> +err_map: >>> + iio_map_array_unregister(indio_dev); >>> + >>> +err: >>> + pm_runtime_put(&pdev->dev); >>> + pm_runtime_disable(&pdev->dev); >>> + >>> + return ret; >>> +} >>> + >>> +static int sun4i_gpadc_remove(struct platform_device *pdev) >>> +{ >>> + struct sun4i_gpadc_iio *info; >>> + struct iio_dev *indio_dev = platform_get_drvdata(pdev); >>> + >>> + pm_runtime_put(&pdev->dev); >>> + pm_runtime_disable(&pdev->dev); >>> + info = iio_priv(indio_dev); >>> + iio_map_array_unregister(indio_dev); >>> + iio_device_unregister(indio_dev); >>> + >>> + return 0; >>> +} >>> + >>> +static const struct platform_device_id sun4i_gpadc_id[] = { >>> + { "sun4i-a10-gpadc-iio", (kernel_ulong_t)&sun4i_gpadc_data }, >>> + { "sun5i-a13-gpadc-iio", (kernel_ulong_t)&sun5i_gpadc_data }, >>> + { "sun6i-a31-gpadc-iio", (kernel_ulong_t)&sun6i_gpadc_data }, >>> + { /* sentinel */ }, >>> +}; >>> + >>> +static struct platform_driver sun4i_gpadc_driver = { >>> + .driver = { >>> + .name = "sun4i-gpadc-iio", >>> + .pm = &sun4i_gpadc_pm_ops, >>> + }, >>> + .id_table = sun4i_gpadc_id, >>> + .probe = sun4i_gpadc_probe, >>> + .remove = sun4i_gpadc_remove, >>> +}; >>> + >>> +module_platform_driver(sun4i_gpadc_driver); >>> + >>> +MODULE_DESCRIPTION("ADC driver for sunxi platforms"); >>> +MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>"); >>> +MODULE_LICENSE("GPL v2"); >>> >> >
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 25378c5..ea36a4f 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -384,6 +384,19 @@ config ROCKCHIP_SARADC To compile this driver as a module, choose M here: the module will be called rockchip_saradc. +config SUN4I_GPADC + tristate "Support for the Allwinner SoCs GPADC" + depends on IIO + depends on MFD_SUN4I_GPADC + select THERMAL_OF + help + Say yes here to build support for Allwinner (A10, A13 and A31) SoCs + GPADC. This ADC provides 4 channels which can be used as an ADC or as + a touchscreen input and one channel for thermal sensor. + + To compile this driver as a module, choose M here: the module will be + called sun4i-gpadc-iio. + config TI_ADC081C tristate "Texas Instruments ADC081C/ADC101C/ADC121C family" depends on I2C diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 38638d4..204372d 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -37,6 +37,7 @@ obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o +obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o obj-$(CONFIG_TI_ADC128S052) += ti-adc128s052.o diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c new file mode 100644 index 0000000..e2c5ba8 --- /dev/null +++ b/drivers/iio/adc/sun4i-gpadc-iio.c @@ -0,0 +1,522 @@ +/* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC + * + * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com> + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. + * + * The Allwinner SoCs all have an ADC that can also act as a touchscreen + * controller and a thermal sensor. + * The thermal sensor works only when the ADC acts as a touchscreen controller + * and is configured to throw an interrupt every fixed periods of time (let say + * every X seconds). + * One would be tempted to disable the IP on the hardware side rather than + * disabling interrupts to save some power but that resets the internal clock of + * the IP, resulting in having to wait X seconds every time we want to read the + * value of the thermal sensor. + * This is also the reason of using autosuspend in pm_runtime. If there was no + * autosuspend, the thermal sensor would need X seconds after every + * pm_runtime_get_sync to get a value from the ADC. The autosuspend allows the + * thermal sensor to be requested again in a certain time span before it gets + * shutdown for not being used. + */ + +#include <linux/completion.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/thermal.h> + +#include <linux/iio/iio.h> +#include <linux/iio/driver.h> +#include <linux/iio/machine.h> +#include <linux/mfd/sun4i-gpadc.h> + +static unsigned int sun4i_gpadc_chan_select(unsigned int chan) +{ + return SUN4I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); +} + +static unsigned int sun6i_gpadc_chan_select(unsigned int chan) +{ + return SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(chan); +} + +struct gpadc_data { + int temp_offset; + int temp_scale; + unsigned int tp_mode_en; + unsigned int tp_adc_select; + unsigned int (*adc_chan_select)(unsigned int chan); +}; + +static const struct gpadc_data sun4i_gpadc_data = { + .temp_offset = -1932, + .temp_scale = 133, + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, + .adc_chan_select = &sun4i_gpadc_chan_select, +}; + +static const struct gpadc_data sun5i_gpadc_data = { + .temp_offset = -1447, + .temp_scale = 100, + .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN, + .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT, + .adc_chan_select = &sun4i_gpadc_chan_select, +}; + +static const struct gpadc_data sun6i_gpadc_data = { + .temp_offset = -1623, + .temp_scale = 167, + .tp_mode_en = SUN6I_GPADC_CTRL1_TP_MODE_EN, + .tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT, + .adc_chan_select = &sun6i_gpadc_chan_select, +}; + +struct sun4i_gpadc_iio { + struct iio_dev *indio_dev; + struct completion completion; + int temp_data; + u32 adc_data; + struct regmap *regmap; + unsigned int fifo_data_irq; + atomic_t ignore_fifo_data_irq; + unsigned int temp_data_irq; + atomic_t ignore_temp_data_irq; + const struct gpadc_data *data; + /* prevents concurrent reads of temperature and ADC */ + struct mutex mutex; +}; + +#define SUN4I_GPADC_ADC_CHANNEL(_channel, _name) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = _channel, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .datasheet_name = _name, \ +} + +static struct iio_map sun4i_gpadc_hwmon_maps[] = { + { + .adc_channel_label = "temp_adc", + .consumer_dev_name = "iio_hwmon.0", + }, + { /* sentinel */ }, +}; + +static const struct iio_chan_spec sun4i_gpadc_channels[] = { + SUN4I_GPADC_ADC_CHANNEL(0, "adc_chan0"), + SUN4I_GPADC_ADC_CHANNEL(1, "adc_chan1"), + SUN4I_GPADC_ADC_CHANNEL(2, "adc_chan2"), + SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"), + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .datasheet_name = "temp_adc", + }, +}; + +static int sun4i_gpadc_read(struct iio_dev *indio_dev, int channel, int *val, + unsigned int irq) +{ + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); + int ret = 0; + + pm_runtime_get_sync(indio_dev->dev.parent); + mutex_lock(&info->mutex); + + reinit_completion(&info->completion); + + ret = regmap_write(info->regmap, SUN4I_GPADC_INT_FIFOC, + SUN4I_GPADC_INT_FIFOC_TP_FIFO_TRIG_LEVEL(1) | + SUN4I_GPADC_INT_FIFOC_TP_FIFO_FLUSH); + if (ret) + return ret; + + if (irq == info->fifo_data_irq) { + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, + info->data->tp_mode_en | + info->data->tp_adc_select | + info->data->adc_chan_select(channel)); + } else { + /* + * The temperature sensor returns valid data only when the ADC + * operates in touchscreen mode. + */ + ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1, + info->data->tp_mode_en); + } + + if (ret) + return ret; + + enable_irq(irq); + + if (!wait_for_completion_timeout(&info->completion, + msecs_to_jiffies(100))) { + if ((irq == info->fifo_data_irq && info->adc_data == -1) || + (irq == info->temp_data_irq && info->temp_data == -1)) { + ret = -ETIMEDOUT; + goto out; + } + } + + if (irq == info->fifo_data_irq) + *val = info->adc_data; + else + *val = info->temp_data; + + ret = 0; + +out: + disable_irq(irq); + mutex_unlock(&info->mutex); + pm_runtime_mark_last_busy(indio_dev->dev.parent); + pm_runtime_put_autosuspend(indio_dev->dev.parent); + + return ret; +} + +static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel, + int *val) +{ + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); + + return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq); +} + +static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val) +{ + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); + + return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq); +} + +static int sun4i_gpadc_temp_offset(struct iio_dev *indio_dev, int *val) +{ + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); + + *val = info->data->temp_offset; + + return 0; +} + +static int sun4i_gpadc_temp_scale(struct iio_dev *indio_dev, int *val) +{ + struct sun4i_gpadc_iio *info = iio_priv(indio_dev); + + *val = info->data->temp_scale; + + return 0; +} + +static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + int ret; + + switch (mask) { + case IIO_CHAN_INFO_OFFSET: + ret = sun4i_gpadc_temp_offset(indio_dev, val); + if (ret) + return ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_RAW: + if (chan->type == IIO_VOLTAGE) + ret = sun4i_gpadc_adc_read(indio_dev, chan->channel, + val); + else + ret = sun4i_gpadc_temp_read(indio_dev, val); + + if (ret) + return ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + ret = sun4i_gpadc_temp_scale(indio_dev, val); + if (ret) + return ret; + + return IIO_VAL_INT; + default: + return -EINVAL; + } + + return -EINVAL; +} + +static const struct iio_info sun4i_gpadc_iio_info = { + .read_raw = sun4i_gpadc_read_raw, + .driver_module = THIS_MODULE, +}; + +static irqreturn_t sun4i_gpadc_temp_data_irq_handler(int irq, void *dev_id) +{ + struct sun4i_gpadc_iio *info = dev_id; + + if (atomic_read(&info->ignore_temp_data_irq)) + return IRQ_HANDLED; + + if (!regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, &info->temp_data)) + complete(&info->completion); + + return IRQ_HANDLED; +} + +static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id) +{ + struct sun4i_gpadc_iio *info = dev_id; + + if (atomic_read(&info->ignore_fifo_data_irq)) + return IRQ_HANDLED; + + if (!regmap_read(info->regmap, SUN4I_GPADC_DATA, &info->adc_data)) + complete(&info->completion); + + return IRQ_HANDLED; +} + +static int sun4i_gpadc_runtime_suspend(struct device *dev) +{ + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); + + /* Disable the ADC on IP */ + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, 0); + /* Disable temperature sensor on IP */ + regmap_write(info->regmap, SUN4I_GPADC_TPR, 0); + + return 0; +} + +static int sun4i_gpadc_runtime_resume(struct device *dev) +{ + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); + + /* clkin = 6MHz */ + regmap_write(info->regmap, SUN4I_GPADC_CTRL0, + SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(2) | + SUN4I_GPADC_CTRL0_FS_DIV(7) | + SUN4I_GPADC_CTRL0_T_ACQ(63)); + regmap_write(info->regmap, SUN4I_GPADC_CTRL1, info->data->tp_mode_en); + regmap_write(info->regmap, SUN4I_GPADC_CTRL3, + SUN4I_GPADC_CTRL3_FILTER_EN | + SUN4I_GPADC_CTRL3_FILTER_TYPE(1)); + /* period = SUN4I_GPADC_TPR_TEMP_PERIOD * 256 * 16 / clkin; ~1.3s */ + regmap_write(info->regmap, SUN4I_GPADC_TPR, + SUN4I_GPADC_TPR_TEMP_ENABLE | + SUN4I_GPADC_TPR_TEMP_PERIOD(1953)); + + return 0; +} + +static int sun4i_gpadc_get_temp(void *data, int *temp) +{ + struct sun4i_gpadc_iio *info = (struct sun4i_gpadc_iio *)data; + int val, scale, offset; + + /* If reading temperature times out, take stored previous value. */ + if (sun4i_gpadc_temp_read(info->indio_dev, &val)) + val = info->temp_data; + sun4i_gpadc_temp_scale(info->indio_dev, &scale); + sun4i_gpadc_temp_offset(info->indio_dev, &offset); + + *temp = (val + offset) * scale; + + return 0; +} + +static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { + .get_temp = &sun4i_gpadc_get_temp, +}; + +static const struct dev_pm_ops sun4i_gpadc_pm_ops = { + .runtime_suspend = &sun4i_gpadc_runtime_suspend, + .runtime_resume = &sun4i_gpadc_runtime_resume, +}; + +static int sun4i_irq_init(struct platform_device *pdev, const char *name, + irq_handler_t handler, const char *devname, + unsigned int *irq, atomic_t *atomic) +{ + int ret; + struct sun4i_gpadc_dev *mfd_dev = dev_get_drvdata(pdev->dev.parent); + struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(&pdev->dev)); + + /* + * Once the interrupt is activated, the IP continuously performs + * conversions thus throws interrupts. The interrupt is activated right + * after being requested but we want to control when these interrupts + * occur thus we disable it right after being requested. However, an + * interrupt might occur between these two instructions and we have to + * make sure that does not happen, by using atomic flags. We set the + * flag before requesting the interrupt and unset it right after + * disabling the interrupt. When an interrupt occurs between these two + * instructions, reading the atomic flag will tell us to ignore the + * interrupt. + */ + atomic_set(atomic, 1); + + *irq = platform_get_irq_byname(pdev, name); + if (*irq < 0) { + dev_err(&pdev->dev, "no %s interrupt registered\n", name); + return *irq; + } + + *irq = regmap_irq_get_virq(mfd_dev->regmap_irqc, *irq); + ret = devm_request_any_context_irq(&pdev->dev, *irq, handler, 0, + devname, info); + if (ret < 0) { + dev_err(&pdev->dev, "could not request %s interrupt: %d\n", + name, ret); + return ret; + } + + disable_irq(*irq); + atomic_set(atomic, 0); + + return 0; +} + +static int sun4i_gpadc_probe(struct platform_device *pdev) +{ + struct sun4i_gpadc_iio *info; + struct iio_dev *indio_dev; + int ret; + struct sun4i_gpadc_dev *sun4i_gpadc_dev; + struct thermal_zone_device *tzd; + + sun4i_gpadc_dev = dev_get_drvdata(pdev->dev.parent); + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); + if (!indio_dev) + return -ENOMEM; + + info = iio_priv(indio_dev); + platform_set_drvdata(pdev, indio_dev); + + mutex_init(&info->mutex); + info->regmap = sun4i_gpadc_dev->regmap; + info->indio_dev = indio_dev; + info->temp_data = -1; + info->adc_data = -1; + init_completion(&info->completion); + 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 = &sun4i_gpadc_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->num_channels = ARRAY_SIZE(sun4i_gpadc_channels); + indio_dev->channels = sun4i_gpadc_channels; + + info->data = (struct gpadc_data *)platform_get_device_id(pdev)->driver_data; + + /* + * This driver is a child of an MFD which has a node in the DT but not + * its children. Therefore, the resulting devices of this driver do not + * have an of_node variable. + * However, its parent (the MFD driver) has an of_node variable and + * since devm_thermal_zone_of_sensor_register uses its first argument to + * match the phandle defined in the node of the thermal driver with the + * of_node of the device passed as first argument and the third argument + * to call ops from thermal_zone_of_device_ops, the solution is to use + * the parent device as first argument to match the phandle with its + * of_node, and the device from this driver as third argument to return + * the temperature. + */ + tzd = devm_thermal_zone_of_sensor_register(pdev->dev.parent, 0, info, + &sun4i_ts_tz_ops); + if (IS_ERR(tzd)) { + dev_err(&pdev->dev, "could not register thermal sensor: %ld\n", + PTR_ERR(tzd)); + return PTR_ERR(tzd); + } + + pm_runtime_set_autosuspend_delay(&pdev->dev, + SUN4I_GPADC_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = sun4i_irq_init(pdev, "TEMP_DATA_PENDING", + sun4i_gpadc_temp_data_irq_handler, "temp_data", + &info->temp_data_irq, &info->ignore_temp_data_irq); + if (ret < 0) + goto err; + + ret = sun4i_irq_init(pdev, "FIFO_DATA_PENDING", + sun4i_gpadc_fifo_data_irq_handler, "fifo_data", + &info->fifo_data_irq, &info->ignore_fifo_data_irq); + if (ret < 0) + goto err; + + ret = iio_map_array_register(indio_dev, sun4i_gpadc_hwmon_maps); + if (ret < 0) { + dev_err(&pdev->dev, "failed to register iio map array\n"); + goto err; + } + + ret = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&pdev->dev, "could not register the device\n"); + goto err_map; + } + + return 0; + +err_map: + iio_map_array_unregister(indio_dev); + +err: + pm_runtime_put(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return ret; +} + +static int sun4i_gpadc_remove(struct platform_device *pdev) +{ + struct sun4i_gpadc_iio *info; + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + + pm_runtime_put(&pdev->dev); + pm_runtime_disable(&pdev->dev); + info = iio_priv(indio_dev); + iio_map_array_unregister(indio_dev); + iio_device_unregister(indio_dev); + + return 0; +} + +static const struct platform_device_id sun4i_gpadc_id[] = { + { "sun4i-a10-gpadc-iio", (kernel_ulong_t)&sun4i_gpadc_data }, + { "sun5i-a13-gpadc-iio", (kernel_ulong_t)&sun5i_gpadc_data }, + { "sun6i-a31-gpadc-iio", (kernel_ulong_t)&sun6i_gpadc_data }, + { /* sentinel */ }, +}; + +static struct platform_driver sun4i_gpadc_driver = { + .driver = { + .name = "sun4i-gpadc-iio", + .pm = &sun4i_gpadc_pm_ops, + }, + .id_table = sun4i_gpadc_id, + .probe = sun4i_gpadc_probe, + .remove = sun4i_gpadc_remove, +}; + +module_platform_driver(sun4i_gpadc_driver); + +MODULE_DESCRIPTION("ADC driver for sunxi platforms"); +MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>"); +MODULE_LICENSE("GPL v2");