[PATCH] iio: adc: exynos_adc: Add support for ADCv3 on exynos7

From: Abhilash Kesavan
Date: Fri Oct 31 2014 - 08:38:20 EST


The ADC on exynos7 is quite similar to ADCv2. The differences are as
follows:
- v3 has 8 input channels (10 in v2).
- v3 does not include an ADC PHY control register.
- Some ADC_CON2 register bits being used in v2 are listed as
reserved in v3. This results in a different init_hw function
for v3.

Signed-off-by: Abhilash Kesavan <a.kesavan@xxxxxxxxxxx>
---
- Based on Naveen's "iio: exynos-adc: use syscon instead of ioremap" patchset
http://comments.gmane.org/gmane.linux.kernel.iio/13943

.../devicetree/bindings/arm/samsung/exynos-adc.txt | 2 ++
drivers/iio/adc/exynos_adc.c | 32 ++++++++++++++++++++
2 files changed, 34 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
index c368210..a11e32c 100644
--- a/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
+++ b/Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt
@@ -14,6 +14,8 @@ Required properties:
for exynos4412/5250 and s5pv210 controllers.
Must be "samsung,exynos-adc-v2" for
future controllers.
+ Must be "samsung,exynos-adc-v3" for
+ the ADC in Exynos7 and compatibles
Must be "samsung,exynos3250-adc" for
controllers compatible with ADC of Exynos3250.
Must be "samsung,s3c2410-adc" for
diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index fe03177..74d0a9d 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_v3_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 exynos_adc_v3_data = {
+ .num_channels = MAX_ADC_V1_CHANNELS,
+ .mask = ADC_DATX_MASK, /* 12 bit ADC resolution */
+
+ .init_hw = exynos_adc_v3_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",
@@ -413,6 +442,9 @@ static const struct of_device_id exynos_adc_match[] = {
.compatible = "samsung,exynos-adc-v2",
.data = &exynos_adc_v2_data,
}, {
+ .compatible = "samsung,exynos-adc-v3",
+ .data = &exynos_adc_v3_data,
+ }, {
.compatible = "samsung,exynos3250-adc",
.data = &exynos3250_adc_data,
},
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/