Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / drivers / iio / adc / rockchip_saradc.c

diff --git a/kernel/drivers/iio/adc/rockchip_saradc.c b/kernel/drivers/iio/adc/rockchip_saradc.c
index 9c311c1..dffff64 100644 (file)
--- a/kernel/drivers/iio/adc/rockchip_saradc.c
+++ b/kernel/drivers/iio/adc/rockchip_saradc.c
@@ -21,6 +21,8 @@
 #include <linux/of_device.h>
 #include <linux/clk.h>
 #include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/reset.h>
 #include <linux/regulator/consumer.h>
 #include <linux/iio/iio.h>
 
@@ -53,6 +55,7 @@ struct rockchip_saradc {
        struct clk              *clk;
        struct completion       completion;
        struct regulator        *vref;
+       struct reset_control    *reset;
        const struct rockchip_saradc_data *data;
        u16                     last_val;
 };
@@ -171,6 +174,16 @@ static const struct of_device_id rockchip_saradc_match[] = {
 };
 MODULE_DEVICE_TABLE(of, rockchip_saradc_match);
 
+/**
+ * Reset SARADC Controller.
+ */
+static void rockchip_saradc_reset_controller(struct reset_control *reset)
+{
+       reset_control_assert(reset);
+       usleep_range(10, 20);
+       reset_control_deassert(reset);
+}
+
 static int rockchip_saradc_probe(struct platform_device *pdev)
 {
        struct rockchip_saradc *info = NULL;
@@ -199,6 +212,20 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
        if (IS_ERR(info->regs))
                return PTR_ERR(info->regs);
 
+       /*
+        * The reset should be an optional property, as it should work
+        * with old devicetrees as well
+        */
+       info->reset = devm_reset_control_get(&pdev->dev, "saradc-apb");
+       if (IS_ERR(info->reset)) {
+               ret = PTR_ERR(info->reset);
+               if (ret != -ENOENT)
+                       return ret;
+
+               dev_dbg(&pdev->dev, "no reset control found\n");
+               info->reset = NULL;
+       }
+
        init_completion(&info->completion);
 
        irq = platform_get_irq(pdev, 0);
@@ -233,6 +260,9 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
                return PTR_ERR(info->vref);
        }
 
+       if (info->reset)
+               rockchip_saradc_reset_controller(info->reset);
+
        /*
         * Use a default value for the converter clock.
         * This may become user-configurable in the future.