iio: adc: exynos_adc: Add support for exynos7

The ADC on exynos7 is quite similar to ADCv2. The differences are as
follows:
	- exynos7-adc has 8 input channels (as against 10 in ADCv2).
	- exynos7 does not include an ADC PHY control register.
	- Some ADC_CON2 register bits being used in ADCv2 are listed as
	  reserved in exynos7-adc. This results in a different init_hw
	  function for exynos7.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

2 files changed, 34 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
index c36821095393..f46ca9a316a2 100644
--- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
+++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
@@ -16,6 +16,8 @@ Required properties:
                                 future controllers.
                         Must be "samsung,exynos3250-adc" for
                                 controllers compatible with ADC of Exynos3250.
+                        Must be "samsung,exynos7-adc" for
+                                the ADC in Exynos7 and compatibles
                         Must be "samsung,s3c2410-adc" for
                                 the ADC in s3c2410 and compatibles
                         Must be "samsung,s3c2416-adc" for
diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index fe0317745436..3a2dbb3b4926 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -390,6 +390,35 @@ static const struct exynos_adc_data exynos3250_adc_data = {
         .start_conv     = exynos_adc_v2_start_conv,
 };
 
+static void exynos_adc_exynos7_init_hw(struct exynos_adc *info)
+{
+        u32 con1, con2;
+
+        if (info->data->needs_adc_phy)
+                regmap_write(info->pmu_map, info->data->phy_offset, 1);
+
+        con1 = ADC_V2_CON1_SOFT_RESET;
+        writel(con1, ADC_V2_CON1(info->regs));
+
+        con2 = readl(ADC_V2_CON2(info->regs));
+        con2 &= ~ADC_V2_CON2_C_TIME(7);
+        con2 |= ADC_V2_CON2_C_TIME(0);
+        writel(con2, ADC_V2_CON2(info->regs));
+
+        /* Enable interrupts */
+        writel(1, ADC_V2_INT_EN(info->regs));
+}
+
+static const struct exynos_adc_data exynos7_adc_data = {
+        .num_channels   = MAX_ADC_V1_CHANNELS,
+        .mask           = ADC_DATX_MASK, /* 12 bit ADC resolution */
+
+        .init_hw        = exynos_adc_exynos7_init_hw,
+        .exit_hw        = exynos_adc_v2_exit_hw,
+        .clear_irq      = exynos_adc_v2_clear_irq,
+        .start_conv     = exynos_adc_v2_start_conv,
+};
+
 static const struct of_device_id exynos_adc_match[] = {
         {
                 .compatible = "samsung,s3c2410-adc",
@@ -415,6 +444,9 @@ static const struct of_device_id exynos_adc_match[] = {
         }, {
                 .compatible = "samsung,exynos3250-adc",
                 .data = &exynos3250_adc_data,
+        }, {
+                .compatible = "samsung,exynos7-adc",
+                .data = &exynos7_adc_data,
         },
         {},
 };