From 43ddebdd096638ef8cd2ec41d6acca3400069171 Mon Sep 17 00:00:00 2001
From: Vincent Whitchurch <vincent.whitchurch@axis.com>
Date: Thu, 29 Oct 2020 09:17:20 +0100
Subject: [PATCH] gpio: mockup: Allow probing from device tree

Allow the mockup driver to be probed via the device tree without any
module parameters, allowing it to be used to configure and test higher
level drivers like the leds-gpio driver and corresponding userspace
before actual hardware is available.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 drivers/gpio/gpio-mockup.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 67ed4f238d43..28b757d34046 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -15,6 +15,7 @@
 #include <linux/irq.h>
 #include <linux/irq_sim.h>
 #include <linux/irqdomain.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
@@ -460,9 +461,16 @@ static int gpio_mockup_probe(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct of_device_id gpio_mockup_of_match[] = {
+	{ .compatible = "gpio-mockup", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, gpio_mockup_of_match);
+
 static struct platform_driver gpio_mockup_driver = {
 	.driver = {
 		.name = "gpio-mockup",
+		.of_match_table = gpio_mockup_of_match,
 	},
 	.probe = gpio_mockup_probe,
 };
@@ -556,8 +564,7 @@ static int __init gpio_mockup_init(void)
 {
 	int i, num_chips, err;
 
-	if ((gpio_mockup_num_ranges < 2) ||
-	    (gpio_mockup_num_ranges % 2) ||
+	if ((gpio_mockup_num_ranges % 2) ||
 	    (gpio_mockup_num_ranges > GPIO_MOCKUP_MAX_RANGES))
 		return -EINVAL;