iio: adc: npcm: Add NPCM8XX support

Adding ADC NPCM8XX support to NPCM ADC driver.
ADC NPCM8XX uses a different resolution and voltage reference.

As part of adding NPCM8XX support:
- Add NPCM8XX specific compatible string.
- Add data to handle architecture-specific ADC parameters.

Signed-off-by: Tomer Maimon <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/adc/npcm_adc.c

···
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/spinlock.h>
 #include <linux/uaccess.h>
 #include <linux/reset.h>
+
+struct npcm_adc_info {
+	u32 data_mask;
+	u32 internal_vref;
+	u32 res_bits;
+};
 
 struct npcm_adc {
 	bool int_status;
···
 	 * has finished.
 	 */
 	struct mutex lock;
+	const struct npcm_adc_info *data;
 };
 
 /* ADC registers */
···
 #define NPCM_ADCCON_CH(x)		((x) << 24)
 #define NPCM_ADCCON_DIV_SHIFT		1
 #define NPCM_ADCCON_DIV_MASK		GENMASK(8, 1)
-#define NPCM_ADC_DATA_MASK(x)		((x) & GENMASK(9, 0))
 
 #define NPCM_ADC_ENABLE		(NPCM_ADCCON_ADC_EN | NPCM_ADCCON_ADC_INT_EN)
 
 /* ADC General Definition */
-#define NPCM_RESOLUTION_BITS		10
-#define NPCM_INT_VREF_MV		2000
+static const struct npcm_adc_info npxm7xx_adc_info = {
+	.data_mask = GENMASK(9, 0),
+	.internal_vref = 2048,
+	.res_bits = 10,
+};
+
+static const struct npcm_adc_info npxm8xx_adc_info = {
+	.data_mask = GENMASK(11, 0),
+	.internal_vref = 1229,
+	.res_bits = 12,
+};
 
 #define NPCM_ADC_CHAN(ch) {					\
 	.type = IIO_VOLTAGE,					\
···
 	if (ret < 0)
 		return ret;
 
-	*val = NPCM_ADC_DATA_MASK(ioread32(info->regs + NPCM_ADCDATA));
+	*val = ioread32(info->regs + NPCM_ADCDATA);
+	*val &= info->data->data_mask;
 
 	return 0;
 }
···
 			vref_uv = regulator_get_voltage(info->vref);
 			*val = vref_uv / 1000;
 		} else {
-			*val = NPCM_INT_VREF_MV;
+			*val = info->data->internal_vref;
 		}
-		*val2 = NPCM_RESOLUTION_BITS;
+		*val2 = info->data->res_bits;
 		return IIO_VAL_FRACTIONAL_LOG2;
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		*val = info->adc_sample_hz;
···
 };
 
 static const struct of_device_id npcm_adc_match[] = {
-	{ .compatible = "nuvoton,npcm750-adc", },
+	{ .compatible = "nuvoton,npcm750-adc", .data = &npxm7xx_adc_info},
+	{ .compatible = "nuvoton,npcm845-adc", .data = &npxm8xx_adc_info},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, npcm_adc_match);
···
 	if (!indio_dev)
 		return -ENOMEM;
 	info = iio_priv(indio_dev);
+
+	info->data = device_get_match_data(dev);
+	if (!info->data)
+		return -EINVAL;
 
 	mutex_init(&info->lock);