iio: adc: at91-sama5d2_adc: fix probe error on missing trigger property

[sfrench/cifs-2.6.git] / drivers / iio / adc / at91-sama5d2_adc.c

diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index bc5b38e3a147e6559e4863bfc39e21115648d7b9..a70ef7fec95f05065295a41280d7b17632aac7c9 100644 (file)
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -225,6 +225,7 @@ struct at91_adc_trigger {
        char                            *name;
        unsigned int                    trgmod_value;
        unsigned int                    edge_type;
+       bool                            hw_trig;
 };
 
 struct at91_adc_state {
@@ -254,16 +255,25 @@ static const struct at91_adc_trigger at91_adc_trigger_list[] = {
                .name = "external_rising",
                .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE,
                .edge_type = IRQ_TYPE_EDGE_RISING,
+               .hw_trig = true,
        },
        {
                .name = "external_falling",
                .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL,
                .edge_type = IRQ_TYPE_EDGE_FALLING,
+               .hw_trig = true,
        },
        {
                .name = "external_any",
                .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY,
                .edge_type = IRQ_TYPE_EDGE_BOTH,
+               .hw_trig = true,
+       },
+       {
+               .name = "software",
+               .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER,
+               .edge_type = IRQ_TYPE_NONE,
+               .hw_trig = false,
        },
 };
 
@@ -597,7 +607,7 @@ static int at91_adc_probe(struct platform_device *pdev)
        struct at91_adc_state *st;
        struct resource *res;
        int ret, i;
-       u32 edge_type;
+       u32 edge_type = IRQ_TYPE_NONE;
 
        indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
        if (!indio_dev)
@@ -641,14 +651,14 @@ static int at91_adc_probe(struct platform_device *pdev)
        ret = of_property_read_u32(pdev->dev.of_node,
                                   "atmel,trigger-edge-type", &edge_type);
        if (ret) {
-               dev_err(&pdev->dev,
-                       "invalid or missing value for atmel,trigger-edge-type\n");
-               return ret;
+               dev_dbg(&pdev->dev,
+                       "atmel,trigger-edge-type not specified, only software trigger available\n");
        }
 
        st->selected_trig = NULL;
 
-       for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++)
+       /* find the right trigger, or no trigger at all */
+       for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT + 1; i++)
                if (at91_adc_trigger_list[i].edge_type == edge_type) {
                        st->selected_trig = &at91_adc_trigger_list[i];
                        break;
@@ -717,24 +727,27 @@ static int at91_adc_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, indio_dev);
 
-       ret = at91_adc_buffer_init(indio_dev);
-       if (ret < 0) {
-               dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
-               goto per_clk_disable_unprepare;
-       }
+       if (st->selected_trig->hw_trig) {
+               ret = at91_adc_buffer_init(indio_dev);
+               if (ret < 0) {
+                       dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
+                       goto per_clk_disable_unprepare;
+               }
 
-       ret = at91_adc_trigger_init(indio_dev);
-       if (ret < 0) {
-               dev_err(&pdev->dev, "couldn't setup the triggers.\n");
-               goto per_clk_disable_unprepare;
+               ret = at91_adc_trigger_init(indio_dev);
+               if (ret < 0) {
+                       dev_err(&pdev->dev, "couldn't setup the triggers.\n");
+                       goto per_clk_disable_unprepare;
+               }
        }
 
        ret = iio_device_register(indio_dev);
        if (ret < 0)
                goto per_clk_disable_unprepare;
 
-       dev_info(&pdev->dev, "setting up trigger as %s\n",
-                st->selected_trig->name);
+       if (st->selected_trig->hw_trig)
+               dev_info(&pdev->dev, "setting up trigger as %s\n",
+                        st->selected_trig->name);
 
        dev_info(&pdev->dev, "version: %x\n",
                 readl_relaxed(st->base + AT91_SAMA5D2_VERSION));