On Mon, 3 Aug 2015, Sanchayan Maity wrote: > This patch adds support for IIO buffer to the Vybrid ADC driver. > IIO triggered buffer infrastructure along with iio sysfs trigger > is used to leverage continuous sampling support provided by the > ADC block.
comments below > Signed-off-by: Sanchayan Maity <[email protected]> > --- > drivers/iio/adc/Kconfig | 4 ++ > drivers/iio/adc/vf610_adc.c | 122 > +++++++++++++++++++++++++++++++++++++++++--- > 2 files changed, 120 insertions(+), 6 deletions(-) > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 7c55658..4661241 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -337,6 +337,10 @@ config TWL6030_GPADC > config VF610_ADC > tristate "Freescale vf610 ADC driver" > depends on OF > + select IIO_BUFFER > + select IIO_TRIGGER > + select IIO_SYSFS_TRIGGER > + select IIO_TRIGGERED_BUFFER > help > Say yes here to support for Vybrid board analog-to-digital converter. > Since the IP is used for i.MX6SLX, the driver also support i.MX6SLX. > diff --git a/drivers/iio/adc/vf610_adc.c b/drivers/iio/adc/vf610_adc.c > index 23b8fb9..af72b9a 100644 > --- a/drivers/iio/adc/vf610_adc.c > +++ b/drivers/iio/adc/vf610_adc.c > @@ -34,8 +34,11 @@ > #include <linux/err.h> > > #include <linux/iio/iio.h> > +#include <linux/iio/buffer.h> > #include <linux/iio/sysfs.h> > -#include <linux/iio/driver.h> > +#include <linux/iio/trigger.h> > +#include <linux/iio/trigger_consumer.h> > +#include <linux/iio/triggered_buffer.h> > > /* This will be the driver name the kernel reports */ > #define DRIVER_NAME "vf610-adc" > @@ -170,6 +173,7 @@ struct vf610_adc { > u32 sample_freq_avail[5]; > > struct completion completion; > + u16 *buffer; > }; > > static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 }; > @@ -505,12 +509,22 @@ static const struct iio_chan_spec_ext_info > vf610_ext_info[] = { > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ > BIT(IIO_CHAN_INFO_SAMP_FREQ), \ > .ext_info = vf610_ext_info, \ > + .address = (_idx), \ address is not used, no need to set it > + .scan_index = (_idx), \ often this is written .scan_type = {.sign = 'u', ...} > + .scan_type.sign = 'u', \ > + .scan_type.realbits = 12, \ > + .scan_type.storagebits = 16, \ > } > > #define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \ > .type = (_chan_type), \ > .channel = (_idx), \ > .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ > + .address = (_idx), \ > + .scan_index = (_idx), \ > + .scan_type.sign = 'u', \ > + .scan_type.realbits = 12, \ > + .scan_type.storagebits = 16, \ > } > > static const struct iio_chan_spec vf610_adc_iio_channels[] = { > @@ -531,6 +545,7 @@ static const struct iio_chan_spec > vf610_adc_iio_channels[] = { > VF610_ADC_CHAN(14, IIO_VOLTAGE), > VF610_ADC_CHAN(15, IIO_VOLTAGE), > VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP), > + IIO_CHAN_SOFT_TIMESTAMP(32), > /* sentinel */ > }; > > @@ -559,13 +574,21 @@ static int vf610_adc_read_data(struct vf610_adc *info) > > static irqreturn_t vf610_adc_isr(int irq, void *dev_id) > { > - struct vf610_adc *info = (struct vf610_adc *)dev_id; > + struct iio_dev *indio_dev = (struct iio_dev *)dev_id; > + struct vf610_adc *info = iio_priv(indio_dev); > int coco; > > coco = readl(info->regs + VF610_REG_ADC_HS); > if (coco & VF610_ADC_HS_COCO0) { > info->value = vf610_adc_read_data(info); > - complete(&info->completion); > + if (iio_buffer_enabled(indio_dev)) { > + info->buffer[0] = info->value; > + writel(0, info->regs + VF610_REG_ADC_HS); > + iio_push_to_buffers_with_timestamp(indio_dev, > + info->buffer, iio_get_time_ns()); > + iio_trigger_notify_done(indio_dev->trig); > + } else > + complete(&info->completion); > } > > return IRQ_HANDLED; > @@ -612,6 +635,9 @@ static int vf610_read_raw(struct iio_dev *indio_dev, > switch (mask) { > case IIO_CHAN_INFO_RAW: > case IIO_CHAN_INFO_PROCESSED: > + if (iio_buffer_enabled(indio_dev)) > + return -EBUSY; > + > mutex_lock(&indio_dev->mlock); > reinit_completion(&info->completion); > > @@ -694,6 +720,81 @@ static int vf610_write_raw(struct iio_dev *indio_dev, > return -EINVAL; > } > > +static int vf610_adc_buffer_postenable(struct iio_dev *indio_dev) > +{ > + struct vf610_adc *info = iio_priv(indio_dev); > + unsigned int channel; > + int ret; > + int val; > + > + ret = iio_triggered_buffer_postenable(indio_dev); > + if (ret) > + return ret; > + > + val = readl(info->regs + VF610_REG_ADC_GC); > + val |= VF610_ADC_ADCON; > + writel(val, info->regs + VF610_REG_ADC_GC); > + > + channel = find_first_bit(indio_dev->active_scan_mask, > + indio_dev->masklength); > + > + val = VF610_ADC_ADCHC(channel); > + val |= VF610_ADC_AIEN; > + > + writel(val, info->regs + VF610_REG_ADC_HC0); > + > + return 0; > +} > + > +static int vf610_adc_buffer_postdisable(struct iio_dev *indio_dev) > +{ > + struct vf610_adc *info = iio_priv(indio_dev); > + unsigned int hc_cfg = 0; > + int val; > + > + val = readl(info->regs + VF610_REG_ADC_GC); > + val &= ~VF610_ADC_ADCON; > + writel(val, info->regs + VF610_REG_ADC_GC); > + > + hc_cfg |= VF610_ADC_CONV_DISABLE; > + hc_cfg &= ~VF610_ADC_AIEN; > + > + writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); > + > + return 0; > +} > + > +static int vf610_adc_update_scan_mode(struct iio_dev *indio_dev, > + const unsigned long *scan_mask) > +{ > + struct vf610_adc *info = iio_priv(indio_dev); > + > + kfree(info->buffer); only one channel can be read (onehot), why not use a fixed size buffer (one u16, perhaps as a local variable in _adc_isr()? > + info->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL); > + if (!info->buffer) > + return -ENOMEM; > + > + return 0; > +} > + > +static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { > + .postenable = &vf610_adc_buffer_postenable, > + .predisable = &iio_triggered_buffer_predisable, > + .postdisable = &vf610_adc_buffer_postdisable, > + .validate_scan_mask = &iio_validate_scan_mask_onehot, > +}; > + > +static int vf610_adc_buffer_init(struct iio_dev *indio_dev) > +{ > + return iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, > + NULL, &iio_triggered_buffer_setup_ops); > +} > + > +static void vf610_adc_buffer_remove(struct iio_dev *indio_dev) > +{ > + iio_triggered_buffer_cleanup(indio_dev); > +} > + > static int vf610_adc_reg_access(struct iio_dev *indio_dev, > unsigned reg, unsigned writeval, > unsigned *readval) > @@ -714,6 +815,7 @@ static const struct iio_info vf610_adc_iio_info = { > .read_raw = &vf610_read_raw, > .write_raw = &vf610_write_raw, > .debugfs_reg_access = &vf610_adc_reg_access, > + .update_scan_mode = &vf610_adc_update_scan_mode, > .attrs = &vf610_attribute_group, > }; > > @@ -753,7 +855,7 @@ static int vf610_adc_probe(struct platform_device *pdev) > > ret = devm_request_irq(info->dev, irq, > vf610_adc_isr, 0, > - dev_name(&pdev->dev), info); > + dev_name(&pdev->dev), indio_dev); > if (ret < 0) { > dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq); > return ret; > @@ -806,15 +908,22 @@ static int vf610_adc_probe(struct platform_device *pdev) > vf610_adc_cfg_init(info); > vf610_adc_hw_init(info); > > + ret = vf610_adc_buffer_init(indio_dev); > + if (ret < 0) { > + dev_err(&pdev->dev, "Couldn't initialise the buffer\n"); > + goto error_iio_device_register; > + } > + > ret = iio_device_register(indio_dev); > if (ret) { > dev_err(&pdev->dev, "Couldn't register the device.\n"); > - goto error_iio_device_register; > + goto error_adc_buffer_init; > } > > return 0; > > - > +error_adc_buffer_init: > + vf610_adc_buffer_remove(indio_dev); > error_iio_device_register: > clk_disable_unprepare(info->clk); > error_adc_clk_enable: > @@ -829,6 +938,7 @@ static int vf610_adc_remove(struct platform_device *pdev) > struct vf610_adc *info = iio_priv(indio_dev); > > iio_device_unregister(indio_dev); > + vf610_adc_buffer_remove(indio_dev); > regulator_disable(info->vref); > clk_disable_unprepare(info->clk); > > -- Peter Meerwald +43-664-2444418 (mobile) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
