On 01/03/16 11:56, Sean Nyekjaer wrote:
> Devicetree can provide platform data
>
> Signed-off-by: Sean Nyekjaer <sean.nyekjaer@xxxxxxxxx>
> ---
> These large switch cases make the driver hard to read? Does someone have any
> ideas to make this more readable?
Only option that comes to mind would be to use a look up table and search
it... See below. Moves the switch statement stuff into a static array. Can
be done neater than I have below, but you'll get the idea.
>
> The dc-dc-phase and channel mode i rather hard to do without defines? Will it
> be okay to use them here?
> Example:
> adi,mode = CURRENT_4mA_20mA or adi,mode = VOLTAGE_PLUSMINUS_10V
> They are generic DAC/ADC properties...
I can't think of a better way - there are too many missing cases that are
invalid to break it up into more elements. So sure, fine in my view as is.
>
> Changes since v3:
> - replaced '_' with '-'
> - Now used actual values instead of register values.
>
> Changes since v2:
> - removed defines from DT
>
> drivers/iio/dac/ad5755.c | 227 ++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 226 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/dac/ad5755.c b/drivers/iio/dac/ad5755.c
> index e1b6e78..4a2866e 100644
> --- a/drivers/iio/dac/ad5755.c
> +++ b/drivers/iio/dac/ad5755.c
> @@ -14,6 +14,7 @@
> #include <linux/slab.h>
> #include <linux/sysfs.h>
> #include <linux/delay.h>
> +#include <linux/of.h>
> #include <linux/iio/iio.h>
> #include <linux/iio/sysfs.h>
> #include <linux/platform_data/ad5755.h>
> @@ -556,6 +557,223 @@ static const struct ad5755_platform_data ad5755_default_pdata = {
> },
> };
>
> +#ifdef CONFIG_OF
> +static struct ad5755_platform_data *ad5755_parse_dt(struct device *dev)
> +{
> + struct device_node *np = dev->of_node;
> + struct device_node *pp;
> + struct ad5755_platform_data *pdata;
> + unsigned int tmp;
> + unsigned int tmparray[3];
> + int devnr;
> +
> + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata)
> + return NULL;
> +
> + pdata->ext_dc_dc_compenstation_resistor =
> + of_property_read_bool(np, "adi,ext-dc-dc-compenstation-resistor");
> +
> + if (!of_property_read_u32(np, "adi,dc-dc-phase", &tmp))
> + pdata->dc_dc_phase = tmp;
> + else
> + pdata->dc_dc_phase = AD5755_DC_DC_PHASE_ALL_SAME_EDGE;
> +
> + if (!of_property_read_u32(np, "adi,dc-dc-freq", &tmp))
> + switch (tmp) {
static const int ad5755_dcdc_freq_table[3][2] =
{ { 250000, AD5755_DC_DC_FREQ_250kHZ },
{ 410000, AD5755_DC_DC_FREQ_410kHZ },
{ 650000, AD5755_DC_DC_FREQ_650kZ } };
for (i = 0; i < 3; i++) {
if (tmp == ad5755_dcdc_freq_table[i][0]) {
pdata->dc_dc_freq = ad5755_dcdc_freq_table[i][1];
break;
}
if (i == 3) {
dev_err(dev,
"adi,dc-dc-freq out of range selecting 410kHz");
pdata->dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ;
}
Or something along those lines.. Makes more sense for the larger ones.
> + case 250000:
> + pdata->dc_dc_freq = AD5755_DC_DC_FREQ_250kHZ;
> + break;
> + case 410000:
> + pdata->dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ;
> + break;
> + case 650000:
> + pdata->dc_dc_freq = AD5755_DC_DC_FREQ_650kHZ;
> + break;
> + default:
> + dev_err(dev,
> + "adi,dc-dc-freq out of range selecting 410kHz");
> + pdata->dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ;
> + } else
> + pdata->dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ;
> +
> + if (!of_property_read_u32(np, "adi,dc-dc-maxv", &tmp))
> + switch (tmp) {
> + case 23000:
> + pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_23V;
> + break;
> + case 24500:
> + pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_24V5;
> + break;
> + case 27000:
> + pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_27V;
> + break;
> + case 29500:
> + pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_29V5;
> + break;
> + default:
> + dev_err(dev,
> + "adi,dc-dc-maxv out of range selecting 23V");
> + pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_23V;
> + } else
> + pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_23V;
> +
> + devnr = 0;
> + for_each_child_of_node(np, pp) {
> + if (devnr > AD5755_NUM_CHANNELS) {
> + dev_err(dev,
> + "There is to many channels defined in DT\n");
> + goto error_out;
> + }
> +
> + if (!of_property_read_u32(pp, "adi,mode", &tmp))
> + pdata->dac[devnr].mode = tmp;
> + else
> + pdata->dac[devnr].mode = AD5755_MODE_CURRENT_4mA_20mA;
> +
> + pdata->dac[devnr].ext_current_sense_resistor =
> + of_property_read_bool(pp, "adi,ext-current-sense-resistor");
> +
> + pdata->dac[devnr].enable_voltage_overrange =
> + of_property_read_bool(pp, "adi,enable-voltage-overrange");
> +
> + if (!of_property_read_u32_array(pp, "adi,slew", tmparray, 3)) {
> + pdata->dac[devnr].slew.enable = tmparray[0];
> + switch (tmparray[1]) {
> + case 64000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_64k;
> + break;
> + case 32000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_32k;
> + break;
> + case 16000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_16k;
> + break;
> + case 8000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_8k;
> + break;
> + case 4000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_4k;
> + break;
> + case 2000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_2k;
> + break;
> + case 1000:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_1k;
> + break;
> + case 500:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_500;
> + break;
> + case 250:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_250;
> + break;
> + case 125:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_125;
> + break;
> + case 64:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_64;
> + break;
> + case 32:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_32;
> + break;
> + case 16:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_16;
> + break;
> + case 8:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_8;
> + break;
> + case 4:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_4;
> + break;
> + case 0:
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_0_5;
> + break;
> + default:
> + dev_err(dev,
> + "channel %d slew rate out of range selecting 64kHz",
> + devnr);
> + pdata->dac[devnr].slew.rate =
> + AD5755_SLEW_RATE_64k;
> + }
> + switch (tmparray[2]) {
> + case 1:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_1;
> + break;
> + case 2:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_2;
> + break;
> + case 4:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_4;
> + break;
> + case 16:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_16;
> + break;
> + case 32:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_32;
> + break;
> + case 64:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_64;
> + break;
> + case 128:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_128;
> + break;
> + case 256:
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_256;
> + break;
> + default:
> + dev_err(dev,
> + "channel %d slew step size out of range selecting 1 LSB",
> + devnr);
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_1;
> + }
> + } else {
> + pdata->dac[devnr].slew.enable = false;
> + pdata->dac[devnr].slew.rate = AD5755_SLEW_RATE_64k;
> + pdata->dac[devnr].slew.step_size =
> + AD5755_SLEW_STEP_SIZE_1;
> + }
> + devnr++;
> + }
> +
> + return pdata;
> +
> + error_out:
> + devm_kfree(dev, pdata);
> + return NULL;
> +}
> +#else
> +static
> +struct adf4350_platform_data *adf4350_parse_dt(struct device *dev)
> +{
> + return NULL;
> +}
> +#endif
> +
> static int ad5755_probe(struct spi_device *spi)
> {
> enum ad5755_type type = spi_get_device_id(spi)->driver_data;
> @@ -583,8 +801,15 @@ static int ad5755_probe(struct spi_device *spi)
> indio_dev->modes = INDIO_DIRECT_MODE;
> indio_dev->num_channels = AD5755_NUM_CHANNELS;
>
> - if (!pdata)
> + if (spi->dev.of_node)
> + pdata = ad5755_parse_dt(&spi->dev);
> + else
> + pdata = spi->dev.platform_data;
> +
> + if (!pdata) {
> + dev_warn(&spi->dev, "no platform data? using default\n");
> pdata = &ad5755_default_pdata;
> + }
>
> ret = ad5755_init_channels(indio_dev, pdata);
> if (ret)
>
--
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