From faeea753ba262e2a781570f9db23c5773c5d20e7 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Mon, 23 Dec 2019 19:58:08 +0100
Subject: [PATCH] clk: bcm: rpi: Allow the driver to be probed by DT

The current firmware clock driver for the RaspberryPi can only be probed by
manually registering an associated platform_device.

While this works fine for cpufreq where the device gets attached a clkdev
lookup, it would be tedious to maintain a table of all the devices using
one of the clocks exposed by the firmware.

Since the DT on the other hand is the perfect place to store those
associations, make the firmware clocks driver probe-able through the device
tree so that we can represent it as a node.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-clk@vger.kernel.org
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/clk/bcm/clk-raspberrypi.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -255,15 +255,13 @@ static int raspberrypi_clk_probe(struct
 	struct raspberrypi_clk *rpi;
 	int ret;
 
-	firmware_node = of_find_compatible_node(NULL, NULL,
-					"raspberrypi,bcm2835-firmware");
+	firmware_node = of_parse_phandle(dev->of_node, "raspberrypi,firmware", 0);
 	if (!firmware_node) {
 		dev_err(dev, "Missing firmware node\n");
 		return -ENOENT;
 	}
 
 	firmware = rpi_firmware_get(firmware_node);
-	of_node_put(firmware_node);
 	if (!firmware)
 		return -EPROBE_DEFER;
 
@@ -300,9 +298,16 @@ static int raspberrypi_clk_remove(struct
 	return 0;
 }
 
+static const struct of_device_id raspberrypi_clk_match[] = {
+        { .compatible = "raspberrypi,firmware-clocks" },
+        { },
+};
+MODULE_DEVICE_TABLE(of, raspberrypi_clk_match);
+
 static struct platform_driver raspberrypi_clk_driver = {
 	.driver = {
 		.name = "raspberrypi-clk",
+		.of_match_table = raspberrypi_clk_match,
 	},
 	.probe          = raspberrypi_clk_probe,
 	.remove		= raspberrypi_clk_remove,
