iio: adc: aspeed: completes the bitfield declare.

This patch completes the declare of ADC register bitfields and uses the
same prefix ASPEED_ADC_* for these bitfields. In addition, tidy up space
alignment of the codes.

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

drivers/iio/adc/aspeed_adc.c

···
  * Aspeed AST2400/2500 ADC
  *
  * Copyright (C) 2017 Google, Inc.
+ * Copyright (C) 2021 Aspeed Technology Inc.
  */
 
 #include <linux/clk.h>
···
 #include <linux/reset.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>
+#include <linux/bitfield.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/driver.h>
···
 #define ASPEED_REG_INTERRUPT_CONTROL	0x04
 #define ASPEED_REG_VGA_DETECT_CONTROL	0x08
 #define ASPEED_REG_CLOCK_CONTROL	0x0C
-#define ASPEED_REG_MAX			0xC0
+#define ASPEED_REG_COMPENSATION_TRIM	0xC4
+/*
+ * The register offset between 0xC8~0xCC can be read and won't affect the
+ * hardware logic in each version of ADC.
+ */
+#define ASPEED_REG_MAX			0xD0
 
-#define ASPEED_OPERATION_MODE_POWER_DOWN	(0x0 << 1)
-#define ASPEED_OPERATION_MODE_STANDBY		(0x1 << 1)
-#define ASPEED_OPERATION_MODE_NORMAL		(0x7 << 1)
-
-#define ASPEED_ENGINE_ENABLE		BIT(0)
-
-#define ASPEED_ADC_CTRL_INIT_RDY	BIT(8)
+#define ASPEED_ADC_ENGINE_ENABLE		BIT(0)
+#define ASPEED_ADC_OP_MODE			GENMASK(3, 1)
+#define ASPEED_ADC_OP_MODE_PWR_DOWN		0
+#define ASPEED_ADC_OP_MODE_STANDBY		1
+#define ASPEED_ADC_OP_MODE_NORMAL		7
+#define ASPEED_ADC_CTRL_COMPENSATION		BIT(4)
+#define ASPEED_ADC_AUTO_COMPENSATION		BIT(5)
+/*
+ * Bit 6 determines not only the reference voltage range but also the dividing
+ * circuit for battery sensing.
+ */
+#define ASPEED_ADC_REF_VOLTAGE			GENMASK(7, 6)
+#define ASPEED_ADC_REF_VOLTAGE_2500mV		0
+#define ASPEED_ADC_REF_VOLTAGE_1200mV		1
+#define ASPEED_ADC_REF_VOLTAGE_EXT_HIGH		2
+#define ASPEED_ADC_REF_VOLTAGE_EXT_LOW		3
+#define ASPEED_ADC_BAT_SENSING_DIV		BIT(6)
+#define ASPEED_ADC_BAT_SENSING_DIV_2_3		0
+#define ASPEED_ADC_BAT_SENSING_DIV_1_3		1
+#define ASPEED_ADC_CTRL_INIT_RDY		BIT(8)
+#define ASPEED_ADC_CH7_MODE			BIT(12)
+#define ASPEED_ADC_CH7_NORMAL			0
+#define ASPEED_ADC_CH7_BAT			1
+#define ASPEED_ADC_BAT_SENSING_ENABLE		BIT(13)
+#define ASPEED_ADC_CTRL_CHANNEL			GENMASK(31, 16)
+#define ASPEED_ADC_CTRL_CHANNEL_ENABLE(ch)	FIELD_PREP(ASPEED_ADC_CTRL_CHANNEL, BIT(ch))
 
 #define ASPEED_ADC_INIT_POLLING_TIME	500
 #define ASPEED_ADC_INIT_TIMEOUT		500000
···
 
 	if (model_data->wait_init_sequence) {
 		/* Enable engine in normal mode. */
-		writel(ASPEED_OPERATION_MODE_NORMAL | ASPEED_ENGINE_ENABLE,
+		writel(FIELD_PREP(ASPEED_ADC_OP_MODE,
+				  ASPEED_ADC_OP_MODE_NORMAL) |
+			       ASPEED_ADC_ENGINE_ENABLE,
 		       data->base + ASPEED_REG_ENGINE_CONTROL);
 
 		/* Wait for initial sequence complete. */
···
 	if (ret)
 		goto clk_enable_error;
 
-	adc_engine_control_reg_val = GENMASK(31, 16) |
-		ASPEED_OPERATION_MODE_NORMAL | ASPEED_ENGINE_ENABLE;
+	adc_engine_control_reg_val =
+		ASPEED_ADC_CTRL_CHANNEL |
+		FIELD_PREP(ASPEED_ADC_OP_MODE, ASPEED_ADC_OP_MODE_NORMAL) |
+		ASPEED_ADC_ENGINE_ENABLE;
 	writel(adc_engine_control_reg_val,
-		data->base + ASPEED_REG_ENGINE_CONTROL);
+	       data->base + ASPEED_REG_ENGINE_CONTROL);
 
 	model_data = of_device_get_match_data(&pdev->dev);
 	indio_dev->name = model_data->model_name;
···
 	return 0;
 
 iio_register_error:
-	writel(ASPEED_OPERATION_MODE_POWER_DOWN,
-		data->base + ASPEED_REG_ENGINE_CONTROL);
+	writel(FIELD_PREP(ASPEED_ADC_OP_MODE, ASPEED_ADC_OP_MODE_PWR_DOWN),
+	       data->base + ASPEED_REG_ENGINE_CONTROL);
 	clk_disable_unprepare(data->clk_scaler->clk);
 clk_enable_error:
 poll_timeout_error:
···
 	struct aspeed_adc_data *data = iio_priv(indio_dev);
 
 	iio_device_unregister(indio_dev);
-	writel(ASPEED_OPERATION_MODE_POWER_DOWN,
-		data->base + ASPEED_REG_ENGINE_CONTROL);
+	writel(FIELD_PREP(ASPEED_ADC_OP_MODE, ASPEED_ADC_OP_MODE_PWR_DOWN),
+	       data->base + ASPEED_REG_ENGINE_CONTROL);
 	clk_disable_unprepare(data->clk_scaler->clk);
 	reset_control_assert(data->rst);
 	clk_hw_unregister_divider(data->clk_scaler);