Re: [PATCH] iio: adc: rockchip_saradc: add support for rk3066-tsadc variant

Heiko Stübner
2014-08-30T20:36:40Z

Am Samstag, 30. August 2014, 21:15:53 schrieb Jonathan Cameron:
> On 30/08/14 14:07, Heiko Stübner wrote:
> > Older Rockchip SoCs, at least the rk3066, used a slightly modified saradc
> > for temperature measurements. This so called tsadc does not contain any
> > active parts like temperature interrupts and only supports polling the
> > current temperature. The returned voltage can then be converted by a
> > suitable thermal driver to and actual temperature and used for thermal
> > handling.
> >
> > Signed-off-by: Heiko Stuebner <heiko@sntech.de>
>
> Looks, good to me, but will let this sit for a few days for other comments
> on it.

ok, cool

> Long shot, but are the docs for the vairous rockchip parts
> publically available somewhere?

Not publically, at this point ... maybe somewhere in the future [hope :-) ]

Heiko

>
> > ---
> > This is a different IP than the rk3288-tsadc Ceasar provided a driver for.
> > As the commit messages states, the one used on the rk3066 is just a
> > saradc,
> > while the new tsadc in the rk3288 contains active components for thermal
> > handling.
> >
> > A working example using the pending iio-thermal driver can found on
> > https://github.com/mmind/linux-rockchip/commit/c07e02f069d9677d489f2541766
> > 19fae36f2aad0>
> > .../bindings/iio/adc/rockchip-saradc.txt | 2 +-
> > drivers/iio/adc/rockchip_saradc.c | 62
> > +++++++++++++++++----- 2 files changed, 50 insertions(+), 14
> > deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt
> > b/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt index
> > 5d3ec1d..a9a5fe1 100644
> > --- a/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt
> > +++ b/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt
> > @@ -1,7 +1,7 @@
> >
> > Rockchip Successive Approximation Register (SAR) A/D Converter bindings
> >
> > Required properties:
> > -- compatible: Should be "rockchip,saradc"
> > +- compatible: Should be "rockchip,saradc" or "rockchip,rk3066-tsadc"
> >
> > - reg: physical base address of the controller and length of memory
> > mapped
> >
> > region.
> >
> > - interrupts: The interrupt number to the cpu. The interrupt specifier
> > format>
> > diff --git a/drivers/iio/adc/rockchip_saradc.c
> > b/drivers/iio/adc/rockchip_saradc.c index e074a0b..7effada 100644
> > --- a/drivers/iio/adc/rockchip_saradc.c
> > +++ b/drivers/iio/adc/rockchip_saradc.c
> > @@ -18,13 +18,13 @@
> >
> > #include <linux/interrupt.h>
> > #include <linux/io.h>
> > #include <linux/of.h>
> >
> > +#include <linux/of_device.h>
> >
> > #include <linux/clk.h>
> > #include <linux/completion.h>
> > #include <linux/regulator/consumer.h>
> > #include <linux/iio/iio.h>
> >
> > #define SARADC_DATA 0x00
> >
> > -#define SARADC_DATA_MASK 0x3ff
> >
> > #define SARADC_STAS 0x04
> > #define SARADC_STAS_BUSY BIT(0)
> >
> > @@ -38,15 +38,22 @@
> >
> > #define SARADC_DLY_PU_SOC 0x0c
> > #define SARADC_DLY_PU_SOC_MASK 0x3f
> >
> > -#define SARADC_BITS 10
> >
> > #define SARADC_TIMEOUT msecs_to_jiffies(100)
> >
> > +struct rockchip_saradc_data {
> > + int num_bits;
> > + const struct iio_chan_spec *channels;
> > + int num_channels;
> > + unsigned long clk_rate;
> > +};
> > +
> >
> > struct rockchip_saradc {
> >
> > void __iomem *regs;
> > struct clk *pclk;
> > struct clk *clk;
> > struct completion completion;
> > struct regulator *vref;
> >
> > + const struct rockchip_saradc_data *data;
> >
> > u16 last_val;
> >
> > };
> >
> > @@ -90,7 +97,7 @@ static int rockchip_saradc_read_raw(struct iio_dev
> > *indio_dev,>
> > }
> >
> > *val = ret / 1000;
> >
> > - *val2 = SARADC_BITS;
> > + *val2 = info->data->num_bits;
> >
> > return IIO_VAL_FRACTIONAL_LOG2;
> >
> > default:
> > return -EINVAL;
> >
> > @@ -103,7 +110,7 @@ static irqreturn_t rockchip_saradc_isr(int irq, void
> > *dev_id)>
> > /* Read value */
> > info->last_val = readl_relaxed(info->regs + SARADC_DATA);
> >
> > - info->last_val &= SARADC_DATA_MASK;
> > + info->last_val &= BIT(info->data->num_bits) - 1;
> >
> > /* Clear irq & power down adc */
> > writel_relaxed(0, info->regs + SARADC_CTRL);
> >
> > @@ -133,12 +140,44 @@ static const struct iio_chan_spec
> > rockchip_saradc_iio_channels[] = {>
> > ADC_CHANNEL(2, "adc2"),
> >
> > };
> >
> > +static const struct rockchip_saradc_data saradc_data = {
> > + .num_bits = 10,
> > + .channels = rockchip_saradc_iio_channels,
> > + .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
> > + .clk_rate = 1000000,
> > +};
> > +
> > +static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] =
> > {
> > + ADC_CHANNEL(0, "adc0"),
> > + ADC_CHANNEL(1, "adc1"),
> > +};
> > +
> > +static const struct rockchip_saradc_data rk3066_tsadc_data = {
> > + .num_bits = 12,
> > + .channels = rockchip_rk3066_tsadc_iio_channels,
> > + .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
> > + .clk_rate = 50000,
> > +};
> > +
> > +static const struct of_device_id rockchip_saradc_match[] = {
> > + {
> > + .compatible = "rockchip,saradc",
> > + .data = &saradc_data,
> > + }, {
> > + .compatible = "rockchip,rk3066-tsadc",
> > + .data = &rk3066_tsadc_data,
> > + },
> > + {},
> > +};
> > +MODULE_DEVICE_TABLE(of, rockchip_saradc_match);
> > +
> >
> > static int rockchip_saradc_probe(struct platform_device *pdev)
> > {
> >
> > struct rockchip_saradc *info = NULL;
> > struct device_node *np = pdev->dev.of_node;
> > struct iio_dev *indio_dev = NULL;
> > struct resource *mem;
> >
> > + const struct of_device_id *match;
> >
> > int ret;
> > int irq;
> >
> > @@ -152,6 +191,9 @@ static int rockchip_saradc_probe(struct
> > platform_device *pdev)>
> > }
> > info = iio_priv(indio_dev);
> >
> > + match = of_match_device(rockchip_saradc_match, &pdev->dev);
> > + info->data = match->data;
> > +
> >
> > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > info->regs = devm_ioremap_resource(&pdev->dev, mem);
> > if (IS_ERR(info->regs))
> >
> > @@ -195,7 +237,7 @@ static int rockchip_saradc_probe(struct
> > platform_device *pdev)>
> > * Use a default of 1MHz for the converter clock.
> > * This may become user-configurable in the future.
> > */
> >
> > - ret = clk_set_rate(info->clk, 1000000);
> > + ret = clk_set_rate(info->clk, info->data->clk_rate);
> >
> > if (ret < 0) {
> >
> > dev_err(&pdev->dev, "failed to set adc clk rate, %d\n", ret);
> > return ret;
> >
> > @@ -227,8 +269,8 @@ static int rockchip_saradc_probe(struct
> > platform_device *pdev)>
> > indio_dev->info = &rockchip_saradc_iio_info;
> > indio_dev->modes = INDIO_DIRECT_MODE;
> >
> > - indio_dev->channels = rockchip_saradc_iio_channels;
> > - indio_dev->num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels);
> > + indio_dev->channels = info->data->channels;
> > + indio_dev->num_channels = info->data->num_channels;
> >
> > ret = iio_device_register(indio_dev);
> > if (ret)
> >
> > @@ -296,12 +338,6 @@ static int rockchip_saradc_resume(struct device *dev)
> >
> > static SIMPLE_DEV_PM_OPS(rockchip_saradc_pm_ops,
> >
> > rockchip_saradc_suspend, rockchip_saradc_resume);
> >
> > -static const struct of_device_id rockchip_saradc_match[] = {
> > - { .compatible = "rockchip,saradc" },
> > - {},
> > -};
> > -MODULE_DEVICE_TABLE(of, rockchip_saradc_match);
> > -
> >
> > static struct platform_driver rockchip_saradc_driver = {
> >
> > .probe = rockchip_saradc_probe,
> > .remove = rockchip_saradc_remove,