gpio: pl061: proper error messages

This makes the PL061 driver print proper error messages
when probe fails, and also tell us when the chip is finally
registered.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
index b4d4211..eba66c7 100644 (file)
--- a/drivers/gpio/gpio-pl061.c
+++ b/drivers/gpio/gpio-pl061.c
@@ -270,21 +270,27 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
        if (pdata) {
                chip->gc.base = pdata->gpio_base;
                irq_base = pdata->irq_base;
-               if (irq_base <= 0)
+               if (irq_base <= 0) {
+                       dev_err(&adev->dev, "invalid IRQ base in pdata\n");
                        return -ENODEV;
+               }
        } else {
                chip->gc.base = -1;
                irq_base = 0;
        }
 
        if (!devm_request_mem_region(dev, adev->res.start,
-                                    resource_size(&adev->res), "pl061"))
+                                    resource_size(&adev->res), "pl061")) {
+               dev_err(&adev->dev, "no memory region\n");
                return -EBUSY;
+       }
 
        chip->base = devm_ioremap(dev, adev->res.start,
                                  resource_size(&adev->res));
-       if (!chip->base)
+       if (!chip->base) {
+               dev_err(&adev->dev, "could not remap memory\n");
                return -ENOMEM;
+       }
 
        spin_lock_init(&chip->lock);
 
@@ -309,16 +315,20 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
         */
        writeb(0, chip->base + GPIOIE); /* disable irqs */
        irq = adev->irq[0];
-       if (irq < 0)
+       if (irq < 0) {
+               dev_err(&adev->dev, "invalid IRQ\n");
                return -ENODEV;
+       }
 
        irq_set_chained_handler(irq, pl061_irq_handler);
        irq_set_handler_data(irq, chip);
 
        chip->domain = irq_domain_add_simple(adev->dev.of_node, PL061_GPIO_NR,
                                             irq_base, &pl061_domain_ops, chip);
-       if (!chip->domain)
+       if (!chip->domain) {
+               dev_err(&adev->dev, "no irq domain\n");
                return -ENODEV;
+       }
 
        for (i = 0; i < PL061_GPIO_NR; i++) {
                if (pdata) {
@@ -331,6 +341,8 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
        }
 
        amba_set_drvdata(adev, chip);
+       dev_info(&adev->dev, "PL061 GPIO chip @%08x registered\n",
+               adev->res.start);
 
        return 0;
 }