On Fri, 26 Jan 2018 16:19:30 +0100 Philipp Rossak <[email protected]> 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]> > Signed-off-by: Icenowy Zheng <[email protected]> Both clock and reset code is safe against null parameters, so you can drop a lot of 'is it here' checks in this. They could be argued to act as documentation of the fact we really don't expect them in some cases I suppose... > --- > drivers/iio/adc/sun4i-gpadc-iio.c | 80 > +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 80 insertions(+) > > diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c > b/drivers/iio/adc/sun4i-gpadc-iio.c > index 363936b37c5a..1a80744bd472 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> > > @@ -75,6 +77,9 @@ struct gpadc_data { > u32 ctrl2_map; > u32 sensor_en_map; > u32 filter_map; > + bool has_bus_clk; > + bool has_bus_rst; > + bool has_mod_clk; > }; > > static const struct gpadc_data sun4i_gpadc_data = { > @@ -134,6 +139,9 @@ struct sun4i_gpadc_iio { > atomic_t ignore_temp_data_irq; > const struct gpadc_data *data; > bool no_irq; > + struct clk *bus_clk; > + struct clk *mod_clk; > + struct reset_control *reset; > /* prevents concurrent reads of temperature and ADC */ > struct mutex mutex; > struct thermal_zone_device *tzd; > @@ -435,6 +443,12 @@ static int sun4i_gpadc_runtime_suspend(struct device > *dev) > { > struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); > > + if (info->data->has_mod_clk) > + clk_disable(info->mod_clk); Safe against null parameter... (see below) > + > + if (info->data->has_bus_clk) > + clk_disable(info->bus_clk); > + > return info->data->sample_end(info); > } > > @@ -483,6 +497,12 @@ static int sun4i_gpadc_runtime_resume(struct device *dev) > { > struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev)); > > + if (info->data->has_mod_clk) > + clk_enable(info->mod_clk); clk_enable is safe against null parameter so could do without the checks. > + > + if (info->data->has_bus_clk) > + clk_enable(info->bus_clk); > + > return info->data->sample_start(info); > } > > @@ -597,10 +617,61 @@ static int sun4i_gpadc_probe_dt(struct platform_device > *pdev, > return ret; > } > > + 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; > + } > + > + 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 6MHz */ > + ret = clk_set_rate(info->mod_clk, 4000000); > + if (ret) > + goto disable_bus_clk; > + > + ret = clk_prepare_enable(info->mod_clk); > + if (ret) > + goto disable_bus_clk; > + } > + > if (IS_ENABLED(CONFIG_THERMAL_OF)) > info->sensor_device = &pdev->dev; > > return 0; > + > +disable_bus_clk: > + if (info->data->has_bus_clk) > + clk_disable_unprepare(info->bus_clk); > + > +assert_reset: > + if (info->data->has_bus_rst) > + reset_control_assert(info->reset); > + > + return ret; > } > > static int sun4i_gpadc_probe_mfd(struct platform_device *pdev, > @@ -766,6 +837,15 @@ static int sun4i_gpadc_remove(struct platform_device > *pdev) > if (!info->no_irq) > iio_map_array_unregister(indio_dev); > > + if (info->data->has_mod_clk) > + clk_disable_unprepare(info->mod_clk); clk_disable_unprepare is safe against a null parameter so I don't think the checks are needed. > + > + if (info->data->has_bus_clk) > + clk_disable_unprepare(info->bus_clk); > + > + if (info->data->has_bus_rst) > + reset_control_assert(info->reset); Safe against null parameter... > + > return 0; > } >
