[PATCH] iio: adc: rockchip_saradc: add support for rk3066-tsadc variant
Hartmut Knaack
knaack.h at gmx.de
Tue Sep 2 15:20:58 PDT 2014
Heiko Stübner schrieb:
> 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 at sntech.de>
> ---
Looks mostly good to me, just some minor style issues inline.
> 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/c07e02f069d9677d489f254176619fae36f2aad0
>
> .../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;
> };
The alignment of the whole block should be adjusted to fit with the new element.
>
> @@ -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;
I think using GENMASK would reflect the intention better, that you want to mask out your data.
>
> /* 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,
More information about the linux-arm-kernel
mailing list