mfd: tqmx86: Make IRQ setup errors non-fatal

GPIO IRQ setup can fail either because an invalid IRQ was passed as a
parameter, or because the GPIO controller does not support interrupts.
Neither is severe enough to stop the whole probe; simply disable IRQ
support in the GPIO resource when setup fails.

The code is made a bit more robust by introduing an enum for the
resource list indices instead of assuming that the IRQ is at index 0.

Signed-off-by: Matthias Schiffer <[email protected]>
Link: https://lore.kernel.org/r/2b5522362098d54c6203be6da95bbc545a21fd49.1731325758.git.matthias.schiffer@ew.tq-group.com
Signed-off-by: Lee Jones <[email protected]>

Author: tq-schifferm

drivers/mfd/tqmx86.c

@@ -68,13 +68,15 @@ static const struct resource tqmx_watchdog_resources[] = {
 	DEFINE_RES_IO(TQMX86_IOBASE_WATCHDOG, TQMX86_IOSIZE_WATCHDOG),
 };
 
-/*
- * The IRQ resource must be first, since it is updated with the
- * configured IRQ in the probe function.
- */
+enum tqmx86_gpio_resource_type {
+	TQMX86_GPIO_IO,
+	TQMX86_GPIO_IRQ,
+};
+
 static struct resource tqmx_gpio_resources[] = {
-	DEFINE_RES_IRQ(0),
-	DEFINE_RES_IO(TQMX86_IOBASE_GPIO, TQMX86_IOSIZE_GPIO),
+	[TQMX86_GPIO_IO] = DEFINE_RES_IO(TQMX86_IOBASE_GPIO, TQMX86_IOSIZE_GPIO),
+	/* Placeholder for IRQ resource */
+	[TQMX86_GPIO_IRQ] = {},
 };
 
 static struct i2c_board_info tqmx86_i2c_devices[] = {
@@ -255,13 +257,8 @@ static int tqmx86_probe(struct platform_device *pdev)
 	if (gpio_irq) {
 		err = tqmx86_setup_irq(dev, "GPIO", gpio_irq, io_base,
 				       TQMX86_REG_IO_EXT_INT_GPIO_SHIFT);
-		if (err)
-			return err;
-
-		/* Assumes the IRQ resource is first. */
-		tqmx_gpio_resources[0].start = gpio_irq;
-	} else {
-		tqmx_gpio_resources[0].flags = 0;
+		if (!err)
+			tqmx_gpio_resources[TQMX86_GPIO_IRQ] = DEFINE_RES_IRQ(gpio_irq);
 	}
 
 	ocores_platform_data.clock_khz = tqmx86_board_id_to_clk_rate(dev, board_id);