[PATCHv4 1/4] iio: adc: exynos_adc: Add exynos_adc_ops structure to improve readability

[Chanwoo Choi <cw00.choi@samsung.com>]

This patchset add 'exynos_adc_ops' structure which includes some functions
to control ADC operation according to ADC version (v1 or v2).

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/iio/adc/exynos_adc.c | 174 +++++++++++++++++++++++++++++--------------
 1 file changed, 120 insertions(+), 54 deletions(-)

diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index 010578f..c30def6 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -90,6 +90,7 @@ struct exynos_adc {
 	struct clk		*clk;
 	unsigned int		irq;
 	struct regulator	*vdd;
+	struct exynos_adc_ops	*ops;
 
 	struct completion	completion;
 
@@ -97,6 +98,13 @@ struct exynos_adc {
 	unsigned int            version;
 };
 
+struct exynos_adc_ops {
+	void (*init_hw)(struct exynos_adc *info);
+	void (*clear_irq)(struct exynos_adc *info);
+	void (*start_conv)(struct exynos_adc *info, unsigned long addr);
+	void (*stop_conv)(struct exynos_adc *info);
+};
+
 static const struct of_device_id exynos_adc_match[] = {
 	{ .compatible = "samsung,exynos-adc-v1", .data = (void *)ADC_V1 },
 	{ .compatible = "samsung,exynos-adc-v2", .data = (void *)ADC_V2 },
@@ -112,30 +120,98 @@ static inline unsigned int exynos_adc_get_version(struct platform_device *pdev)
 	return (unsigned int)match->data;
 }
 
-static void exynos_adc_hw_init(struct exynos_adc *info)
+static void exynos_adc_v1_init_hw(struct exynos_adc *info)
+{
+	u32 con1;
+
+	/* set default prescaler values and Enable prescaler */
+	con1 =  ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN;
+
+	/* Enable 12-bit ADC resolution */
+	con1 |= ADC_V1_CON_RES;
+	writel(con1, ADC_V1_CON(info->regs));
+}
+
+static void exynos_adc_v1_start_conv(struct exynos_adc *info, unsigned long addr)
+{
+	u32 con1;
+
+	writel(addr, ADC_V1_MUX(info->regs));
+
+	con1 = readl(ADC_V1_CON(info->regs));
+	writel(con1 | ADC_CON_EN_START, ADC_V1_CON(info->regs));
+}
+
+static void exynos_adc_v1_clear_irq(struct exynos_adc *info)
+{
+	writel(1, ADC_V1_INTCLR(info->regs));
+}
+
+static void exynos_adc_v1_stop_conv(struct exynos_adc *info)
+{
+	u32 con;
+
+	con = readl(ADC_V1_CON(info->regs));
+	con |= ADC_V1_CON_STANDBY;
+	writel(con, ADC_V1_CON(info->regs));
+}
+
+static struct exynos_adc_ops exynos_adc_v1_ops = {
+	.init_hw	= exynos_adc_v1_init_hw,
+	.clear_irq	= exynos_adc_v1_clear_irq,
+	.start_conv	= exynos_adc_v1_start_conv,
+	.stop_conv	= exynos_adc_v1_stop_conv,
+};
+
+static void exynos_adc_v2_init_hw(struct exynos_adc *info)
 {
 	u32 con1, con2;
 
-	if (info->version == ADC_V2) {
-		con1 = ADC_V2_CON1_SOFT_RESET;
-		writel(con1, ADC_V2_CON1(info->regs));
+	con1 = ADC_V2_CON1_SOFT_RESET;
+	writel(con1, ADC_V2_CON1(info->regs));
 
-		con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL |
-			ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0);
-		writel(con2, ADC_V2_CON2(info->regs));
+	con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL |
+		ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0);
+	writel(con2, ADC_V2_CON2(info->regs));
 
-		/* Enable interrupts */
-		writel(1, ADC_V2_INT_EN(info->regs));
-	} else {
-		/* set default prescaler values and Enable prescaler */
-		con1 =  ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN;
+	/* Enable interrupts */
+	writel(1, ADC_V2_INT_EN(info->regs));
+}
 
-		/* Enable 12-bit ADC resolution */
-		con1 |= ADC_V1_CON_RES;
-		writel(con1, ADC_V1_CON(info->regs));
-	}
+static void exynos_adc_v2_start_conv(struct exynos_adc *info, unsigned long addr)
+{
+	u32 con1, con2;
+
+	con2 = readl(ADC_V2_CON2(info->regs));
+	con2 &= ~ADC_V2_CON2_ACH_MASK;
+	con2 |= ADC_V2_CON2_ACH_SEL(addr);
+	writel(con2, ADC_V2_CON2(info->regs));
+
+	con1 = readl(ADC_V2_CON1(info->regs));
+	writel(con1 | ADC_CON_EN_START, ADC_V2_CON1(info->regs));
+}
+
+static void exynos_adc_v2_clear_irq(struct exynos_adc *info)
+{
+	writel(1, ADC_V2_INT_ST(info->regs));
+}
+
+static void exynos_adc_v2_stop_conv(struct exynos_adc *info)
+{
+	u32 con;
+
+	con = readl(ADC_V2_CON1(info->regs));
+	con &= ~ADC_CON_EN_START;
+	writel(con, ADC_V2_CON1(info->regs));
 }
 
+static struct exynos_adc_ops exynos_adc_v2_ops = {
+	.init_hw	= exynos_adc_v2_init_hw,
+	.start_conv	= exynos_adc_v2_start_conv,
+	.clear_irq	= exynos_adc_v2_clear_irq,
+	.stop_conv	= exynos_adc_v2_stop_conv,
+};
+
 static int exynos_read_raw(struct iio_dev *indio_dev,
 				struct iio_chan_spec const *chan,
 				int *val,
@@ -144,7 +220,6 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
 {
 	struct exynos_adc *info = iio_priv(indio_dev);
 	unsigned long timeout;
-	u32 con1, con2;
 	int ret;
 
 	if (mask != IIO_CHAN_INFO_RAW)
@@ -154,28 +229,15 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
 	reinit_completion(&info->completion);
 
 	/* Select the channel to be used and Trigger conversion */
-	if (info->version == ADC_V2) {
-		con2 = readl(ADC_V2_CON2(info->regs));
-		con2 &= ~ADC_V2_CON2_ACH_MASK;
-		con2 |= ADC_V2_CON2_ACH_SEL(chan->address);
-		writel(con2, ADC_V2_CON2(info->regs));
-
-		con1 = readl(ADC_V2_CON1(info->regs));
-		writel(con1 | ADC_CON_EN_START,
-				ADC_V2_CON1(info->regs));
-	} else {
-		writel(chan->address, ADC_V1_MUX(info->regs));
-
-		con1 = readl(ADC_V1_CON(info->regs));
-		writel(con1 | ADC_CON_EN_START,
-				ADC_V1_CON(info->regs));
-	}
+	if (info->ops->start_conv)
+		info->ops->start_conv(info, chan->address);
 
 	timeout = wait_for_completion_timeout
 			(&info->completion, EXYNOS_ADC_TIMEOUT);
 	if (timeout == 0) {
 		dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n");
-		exynos_adc_hw_init(info);
+		if (info->ops->init_hw)
+			info->ops->init_hw(info);
 		ret = -ETIMEDOUT;
 	} else {
 		*val = info->value;
@@ -193,13 +255,11 @@ static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
 	struct exynos_adc *info = (struct exynos_adc *)dev_id;
 
 	/* Read value */
-	info->value = readl(ADC_V1_DATX(info->regs)) &
-						ADC_DATX_MASK;
+	info->value = readl(ADC_V1_DATX(info->regs)) & ADC_DATX_MASK;
+
 	/* clear irq */
-	if (info->version == ADC_V2)
-		writel(1, ADC_V2_INT_ST(info->regs));
-	else
-		writel(1, ADC_V1_INTCLR(info->regs));
+	if (info->ops->clear_irq)
+		info->ops->clear_irq(info);
 
 	complete(&info->completion);
 
@@ -277,6 +337,19 @@ static int exynos_adc_probe(struct platform_device *pdev)
 
 	info = iio_priv(indio_dev);
 
+	info->version = exynos_adc_get_version(pdev);
+	switch (info->version) {
+	case ADC_V1:
+		info->ops = &exynos_adc_v1_ops;
+		break;
+	case ADC_V2:
+		info->ops = &exynos_adc_v2_ops;
+		break;
+	default:
+		dev_err(&pdev->dev, "failed to identify ADC version\n");
+		return -EINVAL;
+	};
+
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	info->regs = devm_ioremap_resource(&pdev->dev, mem);
 	if (IS_ERR(info->regs))
@@ -321,8 +394,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
 
 	writel(1, info->enable_reg);
 
-	info->version = exynos_adc_get_version(pdev);
-
 	platform_set_drvdata(pdev, indio_dev);
 
 	indio_dev->name = dev_name(&pdev->dev);
@@ -349,7 +420,8 @@ static int exynos_adc_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_irq;
 
-	exynos_adc_hw_init(info);
+	if (info->ops->init_hw)
+		info->ops->init_hw(info);
 
 	ret = of_platform_populate(np, exynos_adc_match, NULL, &indio_dev->dev);
 	if (ret < 0) {
@@ -394,17 +466,9 @@ static int exynos_adc_suspend(struct device *dev)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct exynos_adc *info = iio_priv(indio_dev);
-	u32 con;
 
-	if (info->version == ADC_V2) {
-		con = readl(ADC_V2_CON1(info->regs));
-		con &= ~ADC_CON_EN_START;
-		writel(con, ADC_V2_CON1(info->regs));
-	} else {
-		con = readl(ADC_V1_CON(info->regs));
-		con |= ADC_V1_CON_STANDBY;
-		writel(con, ADC_V1_CON(info->regs));
-	}
+	if (info->ops->stop_conv)
+		info->ops->stop_conv(info);
 
 	writel(0, info->enable_reg);
 	clk_disable_unprepare(info->clk);
@@ -428,7 +492,9 @@ static int exynos_adc_resume(struct device *dev)
 		return ret;
 
 	writel(1, info->enable_reg);
-	exynos_adc_hw_init(info);
+
+	if (info->ops->init_hw)
+		info->ops->init_hw(info);
 
 	return 0;
 }
-- 
1.8.0