On Thu, Aug 30, 2018 at 05:45:05PM +0200, Philipp Rossak wrote:
> For adding newer sensor some basic rework of the code is necessary.
> 
> The SoCs after H3 has newer thermal sensor ADCs, which have two clock
> inputs (bus clock and sampling clock) and a reset. The registers are
> also re-arranged.
> 
> This commit reworks the code, adds the process of the clocks and resets.
> 
> Signed-off-by: Philipp Rossak <[email protected]>
> ---
>  drivers/iio/adc/sun4i-gpadc-iio.c | 72 
> +++++++++++++++++++++++++++++++++++++--
>  1 file changed, 70 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c 
> b/drivers/iio/adc/sun4i-gpadc-iio.c
> index c278e165e161..c12de48c4e86 100644
> --- a/drivers/iio/adc/sun4i-gpadc-iio.c
> +++ b/drivers/iio/adc/sun4i-gpadc-iio.c
> @@ -22,6 +22,7 @@
>   * shutdown for not being used.
>   */
>  
> +#include <linux/clk.h>
>  #include <linux/completion.h>
>  #include <linux/interrupt.h>
>  #include <linux/io.h>
> @@ -31,6 +32,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/regmap.h>
> +#include <linux/reset.h>
>  #include <linux/thermal.h>
>  #include <linux/delay.h>
>  
> @@ -63,6 +65,9 @@ struct gpadc_data {
>       int             (*ths_suspend)(struct sun4i_gpadc_iio *info);
>       int             (*ths_resume)(struct sun4i_gpadc_iio *info);
>       bool            support_irq;
> +     bool            has_bus_clk;
> +     bool            has_bus_rst;
> +     bool            has_mod_clk;
>       u32             temp_data_base;
>  };
>  
> @@ -127,6 +132,9 @@ struct sun4i_gpadc_iio {
>       struct mutex                    mutex;
>       struct thermal_zone_device      *tzd;
>       struct device                   *sensor_device;
> +     struct clk                      *bus_clk;
> +     struct clk                      *mod_clk;
> +     struct reset_control            *reset;
>  };
>  
>  static const struct iio_chan_spec sun4i_gpadc_channels[] = {
> @@ -472,8 +480,13 @@ static int sun4i_gpadc_probe_dt(struct platform_device 
> *pdev,
>       if (IS_ERR(base))
>               return PTR_ERR(base);
>  
> -     info->regmap = devm_regmap_init_mmio(&pdev->dev, base,
> -                                          &sun4i_gpadc_regmap_config);
> +     if (info->data->has_bus_clk)
> +             info->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "bus",
> +                             base, &sun4i_gpadc_regmap_config);
> +     else
> +             info->regmap = devm_regmap_init_mmio(&pdev->dev, base,
> +                             &sun4i_gpadc_regmap_config);
> +
>       if (IS_ERR(info->regmap)) {
>               ret = PTR_ERR(info->regmap);
>               dev_err(&pdev->dev, "failed to init regmap: %d\n", ret);
> @@ -498,9 +511,58 @@ static int sun4i_gpadc_probe_dt(struct platform_device 
> *pdev,
>               }
>       }
>  
> +     if (info->data->has_bus_rst) {
> +             info->reset = devm_reset_control_get(&pdev->dev, NULL);
> +             if (IS_ERR(info->reset)) {
> +                     ret = PTR_ERR(info->reset);
> +                     return ret;
> +             }
> +
> +             ret = reset_control_deassert(info->reset);
> +             if (ret)
> +                     return ret;
> +     }
> +
> +     if (info->data->has_bus_clk) {
> +             info->bus_clk = devm_clk_get(&pdev->dev, "bus");
> +             if (IS_ERR(info->bus_clk)) {
> +                     ret = PTR_ERR(info->bus_clk);
> +                     goto assert_reset;
> +             }
> +
> +             ret = clk_prepare_enable(info->bus_clk);
> +             if (ret)
> +                     goto assert_reset;

That should be done in the runtime_resume hook

> +     }
> +
> +     if (info->data->has_mod_clk) {
> +             info->mod_clk = devm_clk_get(&pdev->dev, "mod");
> +             if (IS_ERR(info->mod_clk)) {
> +                     ret = PTR_ERR(info->mod_clk);
> +                     goto disable_bus_clk;
> +             }
> +
> +             /* Running at 4MHz */
> +             ret = clk_set_rate(info->mod_clk, 4000000);
> +             if (ret)
> +                     goto disable_bus_clk;

Why?

> +             ret = clk_prepare_enable(info->mod_clk);
> +             if (ret)
> +                     goto disable_bus_clk;
> +     }
> +
>       info->sensor_device = &pdev->dev;
>  
>       return 0;
> +
> +disable_bus_clk:
> +     clk_disable_unprepare(info->bus_clk);
> +
> +assert_reset:
> +     reset_control_assert(info->reset);

You should check for the variables here before calling those
functions, if you end up here with your variable not set, you'll have
improper refcounting.

Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

-- 
You received this message because you are subscribed to the Google Groups 
"linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/d/optout.

Attachment: signature.asc
Description: PGP signature

Reply via email to