Hi, On Wed, Feb 04, 2015 at 04:48:35PM +0000, Jonathan Cameron wrote: > On 29/01/15 14:09, Markus Pargmann wrote: > > This is a conversion queue driver for the mx25 SoC. It uses the central > > ADC which is used by two seperate independent queues. This driver > > prepares different conversion configurations for each possible input. > > For a conversion it creates a conversionqueue of one item with the > > correct configuration for the chosen channel. It then executes the queue > > once and disables the conversion queue afterwards. > > > > The reference voltages are configurable through devicetree subnodes, > > depending on the connections of the ADC inputs. > > > > Signed-off-by: Markus Pargmann <[email protected]> > > Signed-off-by: Denis Carikli <[email protected]> > > Signed-off-by: Markus Pargmann <[email protected]> > Some really small bits and bobs inline... > Only non trivial one is that I'd prefer that the need for a regulator > in the event of an external reference being specified was explicitly enforced. > > --- > > drivers/iio/adc/Kconfig | 7 + > > drivers/iio/adc/Makefile | 1 + > > drivers/iio/adc/fsl-imx25-gcq.c | 361 > > ++++++++++++++++++++++++++++ > > include/dt-bindings/iio/adc/fsl-imx25-gcq.h | 18 ++ > > 4 files changed, 387 insertions(+) > > create mode 100644 drivers/iio/adc/fsl-imx25-gcq.c > > create mode 100644 include/dt-bindings/iio/adc/fsl-imx25-gcq.h > > > > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > > index 0f79e4725763..fccbb4bf44cc 100644 > > --- a/drivers/iio/adc/Kconfig > > +++ b/drivers/iio/adc/Kconfig > > @@ -143,6 +143,13 @@ config EXYNOS_ADC > > of SoCs for drivers such as the touchscreen and hwmon to use to share > > this resource. > > > > +config FSL_MX25_ADC > > + tristate "Freescale MX25 ADC driver" > > + depends on MFD_MX25_TSADC > > + help > > + Generic Conversion Queue driver used for general purpose ADC in the > > + MX25. This driver supports single measurements using the MX25 ADC. > > + > > config LP8788_ADC > > tristate "LP8788 ADC driver" > > depends on MFD_LP8788 > > diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile > > index 701fdb7c96aa..acab8d956371 100644 > > --- a/drivers/iio/adc/Makefile > > +++ b/drivers/iio/adc/Makefile > > @@ -16,6 +16,7 @@ obj-$(CONFIG_AD799X) += ad799x.o > > obj-$(CONFIG_AT91_ADC) += at91_adc.o > > obj-$(CONFIG_AXP288_ADC) += axp288_adc.o > > obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o > > +obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o > > obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o > > obj-$(CONFIG_MAX1027) += max1027.o > > obj-$(CONFIG_MAX1363) += max1363.o > > diff --git a/drivers/iio/adc/fsl-imx25-gcq.c > > b/drivers/iio/adc/fsl-imx25-gcq.c > > new file mode 100644 > > index 000000000000..398e40c0e4fd > > --- /dev/null > > +++ b/drivers/iio/adc/fsl-imx25-gcq.c > > @@ -0,0 +1,361 @@ > > +/* > > + * Copyright 2014 Markus Pargmann, Pengutronix <[email protected]> > > + * > > + * The code contained herein is licensed under the GNU General Public > > + * License. You may obtain a copy of the GNU General Public License > > + * Version 2 or later at the following locations: > > + * > > + * http://www.opensource.org/licenses/gpl-license.html > > + * http://www.gnu.org/copyleft/gpl.html > > + * > > + * This is the driver for the imx25 GCQ (Generic Conversion Queue) > > + * connected to the imx25 ADC. > > + */ > > + > > +#include <dt-bindings/iio/adc/fsl-imx25-gcq.h> > > +#include <linux/clk.h> > > +#include <linux/iio/iio.h> > > +#include <linux/interrupt.h> > > +#include <linux/mfd/imx25-tsadc.h> > > +#include <linux/module.h> > > +#include <linux/of.h> > > +#include <linux/platform_device.h> > > +#include <linux/regmap.h> > > +#include <linux/regulator/consumer.h> > > + > > +#define MX25_GCQ_TIMEOUT (msecs_to_jiffies(2000)) > > + > > +enum mx25_gcq_cfgs { > > + MX25_CFG_XP = 0, > > + MX25_CFG_YP, > > + MX25_CFG_XN, > > + MX25_CFG_YN, > > + MX25_CFG_WIPER, > > + MX25_CFG_INAUX0, > > + MX25_CFG_INAUX1, > > + MX25_CFG_INAUX2, > > + MX25_NUM_CFGS, > > +}; > > + > > +struct mx25_gcq_priv { > > + struct regmap *regs; > > + struct completion completed; > > + unsigned int settling_time; > > + struct clk *clk; > > + int irq; > > + struct regulator *ext_vref; > > + u32 channel_vref_mv[MX25_NUM_CFGS]; > > +}; > > + > > +#define MX25_CQG_CHAN(chan, id) {\ > > + .type = IIO_VOLTAGE,\ > > + .indexed = 1,\ > > + .channel = chan,\ > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),\ > > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\ > > + .datasheet_name = id,\ > > +} > > + > > +static const struct iio_chan_spec mx25_gcq_channels[MX25_NUM_CFGS] = { > > + MX25_CQG_CHAN(0, "xp"), > > + MX25_CQG_CHAN(1, "yp"), > > + MX25_CQG_CHAN(2, "xn"), > > + MX25_CQG_CHAN(3, "yn"), > > + MX25_CQG_CHAN(4, "wiper"), > > + MX25_CQG_CHAN(5, "inaux0"), > > + MX25_CQG_CHAN(6, "inaux1"), > > + MX25_CQG_CHAN(7, "inaux2"), > > +}; > > + > I'd be tempted to not bother separating out the next two given they > are only used in one place each..
I removed the wrapping functions.
> > +static void mx25_gcq_disable_eoq(struct mx25_gcq_priv *priv)
> > +{
> > + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_EOQ_IRQ,
> > + MX25_ADCQ_MR_EOQ_IRQ);
> > +}
> > +
> > +static void mx25_gcq_enable_eoq(struct mx25_gcq_priv *priv)
> > +{
> > + regmap_update_bits(priv->regs, MX25_ADCQ_MR,
> > + MX25_ADCQ_MR_EOQ_IRQ, 0);
> > +}
> > +
> > +static irqreturn_t mx25_gcq_irq(int irq, void *data)
> > +{
> > + struct mx25_gcq_priv *priv = data;
> > + u32 stats;
> > +
> > + regmap_read(priv->regs, MX25_ADCQ_SR, &stats);
> > +
> > + if (stats & MX25_ADCQ_SR_EOQ) {
> > + mx25_gcq_disable_eoq(priv);
> > + complete(&priv->completed);
> > + }
> > +
> > + /* Disable conversion queue run */
> > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0);
> > +
> > + /* Acknowledge all possible irqs */
> > + regmap_write(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_FRR |
> > + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR |
> > + MX25_ADCQ_SR_EOQ | MX25_ADCQ_SR_PD);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static int mx25_gcq_get_raw_value(struct device *dev,
> > + struct iio_chan_spec const *chan,
> > + struct mx25_gcq_priv *priv,
> > + int *val)
> > +{
> > + long timeout;
> > + u32 data;
> > +
> > + /* Setup the configuration we want to use */
> > + regmap_write(priv->regs, MX25_ADCQ_ITEM_7_0,
> > + MX25_ADCQ_ITEM(0, chan->channel));
> > +
> > + mx25_gcq_enable_eoq(priv);
> > +
> > + /* Trigger queue for one run */
> > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS,
> > + MX25_ADCQ_CR_FQS);
> > +
> > + timeout = wait_for_completion_interruptible_timeout(
> > + &priv->completed, MX25_GCQ_TIMEOUT);
> > + if (timeout < 0) {
> > + dev_err(dev,
> > + "ADC wait for measurement failed\n");
> > + return timeout;
> > + } else if (timeout == 0) {
> > + dev_err(dev, "ADC timed out\n");
> > + return -ETIMEDOUT;
> > + }
> > +
> > + regmap_read(priv->regs, MX25_ADCQ_FIFO, &data);
> > +
> > + *val = MX25_ADCQ_FIFO_DATA(data);
> > +
> > + return IIO_VAL_INT;
> > +}
> > +
> > +static int mx25_gcq_read_raw(struct iio_dev *indio_dev,
> > + struct iio_chan_spec const *chan, int *val,
> > + int *val2, long mask)
> > +{
> > + struct mx25_gcq_priv *priv = iio_priv(indio_dev);
> > + int ret = 0;
> > +
> > + switch (mask) {
> > + case IIO_CHAN_INFO_RAW:
> > + mutex_lock(&indio_dev->mlock);
> > + ret = mx25_gcq_get_raw_value(&indio_dev->dev, chan, priv, val);
> > + mutex_unlock(&indio_dev->mlock);
> > + return ret;
> > +
> > + case IIO_CHAN_INFO_SCALE:
> > + *val = priv->channel_vref_mv[chan->channel];
> > + *val2 = 12;
> > + return IIO_VAL_FRACTIONAL_LOG2;
> > +
> > + default:
> > + return -EINVAL;
> > + }
> > +}
> > +
> > +static const struct iio_info mx25_gcq_iio_info = {
> > + .read_raw = mx25_gcq_read_raw,
> > +};
> > +
> > +static const struct regmap_config mx25_gcq_regconfig = {
> > + .max_register = 0x5c,
> > + .reg_bits = 32,
> > + .val_bits = 32,
> > + .reg_stride = 4,
> > +};
> > +
> > +static int mx25_gcq_setup_cfgs(struct platform_device *pdev,
> > + struct mx25_gcq_priv *priv)
> > +{
> > + struct device_node *np = pdev->dev.of_node;
> > + struct device_node *child;
> > + struct device *dev = &pdev->dev;
> > + int ret, i;
> > +
> > + /*
> > + * Setup all configurations registers with a default conversion
> > + * configuration for each input
> > + */
> > + for (i = 0; i < MX25_NUM_CFGS; ++i)
> > + regmap_write(priv->regs, MX25_ADCQ_CFG(i),
> > + MX25_ADCQ_CFG_YPLL_OFF |
> > + MX25_ADCQ_CFG_XNUR_OFF |
> > + MX25_ADCQ_CFG_XPUL_OFF |
> > + MX25_ADCQ_CFG_REFP_INT |
> > + MX25_ADCQ_CFG_IN(i) |
> > + MX25_ADCQ_CFG_REFN_NGND2);
> > +
> > + for_each_child_of_node(np, child) {
> > + u32 reg;
> > + u32 refp = MX25_ADCQ_CFG_REFP_INT;
> > + u32 refn = MX25_ADCQ_CFG_REFN_NGND2;
> > +
> > + ret = of_property_read_u32(child, "reg", ®);
> > + if (ret) {
> > + dev_err(dev, "Failed to get reg property\n");
> > + return ret;
> > + }
> > +
> > + if (reg >= MX25_NUM_CFGS) {
> > + dev_err(dev,
> > + "reg value is greater than the number of
> > available configuration registers\n");
> > + return -EINVAL;
> > + }
> > +
> > + of_property_read_u32(child, "fsl,adc-refp", &refp);
> > + of_property_read_u32(child, "fsl,adc-refn", &refn);
> > +
> > + /*
> > + * Shift the read values to the correct positions within the
> > + * register.
> > + */
> > + refp = MX25_ADCQ_CFG_REFP(refp);
> > + refn = MX25_ADCQ_CFG_REFN(refn);
> > +
> > + if ((refp & MX25_ADCQ_CFG_REFP_MASK) != refp) {
> > + dev_err(dev, "Invalid fsl,adc-refp property value\n");
> > + return -EINVAL;
> > + }
> > + if ((refn & MX25_ADCQ_CFG_REFN_MASK) != refn) {
> > + dev_err(dev, "Invalid fsl,adc-refn property value");
> > + return -EINVAL;
> > + }
> > +
> > + regmap_update_bits(priv->regs, MX25_ADCQ_CFG(reg),
> > + MX25_ADCQ_CFG_REFP_MASK |
> > + MX25_ADCQ_CFG_REFN_MASK,
> > + refp | refn);
> > + }
> > + regmap_update_bits(priv->regs, MX25_ADCQ_CR,
> > + MX25_ADCQ_CR_FRST | MX25_ADCQ_CR_QRST,
> > + MX25_ADCQ_CR_FRST | MX25_ADCQ_CR_QRST);
> > +
> > + regmap_write(priv->regs, MX25_ADCQ_CR,
> > + MX25_ADCQ_CR_PDMSK |
> > + MX25_ADCQ_CR_QSM_FQS);
> Odd line breaking. I certainly wouldn't break the last two lines.
Fixed
> > +
> > + return 0;
> > +}
> > +
> > +static int mx25_gcq_probe(struct platform_device *pdev)
> > +{
> > + struct iio_dev *indio_dev;
> > + struct mx25_gcq_priv *priv;
> > + struct mx25_tsadc *tsadc = dev_get_drvdata(pdev->dev.parent);
> > + struct device *dev = &pdev->dev;
> > + struct resource *res;
> > + void __iomem *mem;
> > + int ret;
> > +
> > + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
> > + if (!indio_dev)
> > + return -ENOMEM;
> > +
> > + priv = iio_priv(indio_dev);
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + mem = devm_ioremap_resource(dev, res);
> > + if (!mem)
> > + return -ENOMEM;
> > +
> > + priv->regs = devm_regmap_init_mmio(dev, mem, &mx25_gcq_regconfig);
> > + if (IS_ERR(priv->regs)) {
> > + dev_err(dev, "Failed to initialize regmap\n");
> > + return PTR_ERR(priv->regs);
> > + }
> > +
> > + init_completion(&priv->completed);
> > +
> > + /* Optional external regulator */
> > + priv->ext_vref = devm_regulator_get(&pdev->dev, "vref");
> > + if (!IS_ERR_OR_NULL(priv->ext_vref)) {
> > + ret = regulator_enable(priv->ext_vref);
> This is documented in the bindings as being only optional in the sense
> that there may or may not be channels using it. I'd be inclined
> to have it as non optional, but only request it if in use.
>
> If truely optional then should be using the get_optional form as otherwise
> IIRC the regulator framework will feed you a dummy regulator under some
> circumstances.
I now moved the devm_regulator_get() function into
mx25_gcq_setup_cfgs(). After all configs are setup and parsed we know
if the regulator is necessary. So it is still optional and only required
and checked if REFP_EXT is used in the devicetree.
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + ret = mx25_gcq_setup_cfgs(pdev, priv);
> > + if (ret)
> > + return ret;
> > +
> > + priv->clk = tsadc->clk;
> > + ret = clk_prepare_enable(priv->clk);
> > + if (ret) {
> > + dev_err(dev, "Failed to enable clock\n");
> > + return ret;
> > + }
> > +
> > + priv->irq = platform_get_irq(pdev, 0);
> > + if (priv->irq <= 0) {
> > + dev_err(dev, "Failed to get IRQ\n");
> > + ret = priv->irq;
> > + goto err_clk_unprepare;
> > + }
> > +
> > + ret = request_irq(priv->irq, mx25_gcq_irq, 0, pdev->name, priv);
> > + if (ret) {
> > + dev_err(dev, "Failed requesting IRQ\n");
> > + goto err_clk_unprepare;
> > + }
> > +
> > + indio_dev->dev.parent = &pdev->dev;
> > + indio_dev->channels = mx25_gcq_channels;
> > + indio_dev->num_channels = ARRAY_SIZE(mx25_gcq_channels);
> > + indio_dev->info = &mx25_gcq_iio_info;
> > +
> > + ret = iio_device_register(indio_dev);
> > + if (ret) {
> > + dev_err(dev, "Failed to register iio device\n");
> > + goto err_irq_free;
> > + }
> > +
> > + platform_set_drvdata(pdev, priv);
> I'd normally prefer slightly if this used the indio_dev
> (just a case of logically what contains what...)
> Doesn't really matter though.
Changed it to store indio_dev.
Thank you,
Markus
--
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