Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/mfd/bcm2835-pm.c b/drivers/mfd/bcm2835-pm.c
new file mode 100644
index 0000000..42fe67f
--- /dev/null
+++ b/drivers/mfd/bcm2835-pm.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PM MFD driver for Broadcom BCM2835
+ *
+ * This driver binds to the PM block and creates the MFD device for
+ * the WDT and power drivers.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/bcm2835-pm.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+static const struct mfd_cell bcm2835_pm_devs[] = {
+	{ .name = "bcm2835-wdt" },
+};
+
+static const struct mfd_cell bcm2835_power_devs[] = {
+	{ .name = "bcm2835-power" },
+};
+
+static int bcm2835_pm_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct device *dev = &pdev->dev;
+	struct bcm2835_pm *pm;
+	int ret;
+
+	pm = devm_kzalloc(dev, sizeof(*pm), GFP_KERNEL);
+	if (!pm)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, pm);
+
+	pm->dev = dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pm->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(pm->base))
+		return PTR_ERR(pm->base);
+
+	ret = devm_mfd_add_devices(dev, -1,
+				   bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
+				   NULL, 0, NULL);
+	if (ret)
+		return ret;
+
+	/* We'll use the presence of the AXI ASB regs in the
+	 * bcm2835-pm binding as the key for whether we can reference
+	 * the full PM register range and support power domains.
+	 */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (res) {
+		pm->asb = devm_ioremap_resource(dev, res);
+		if (IS_ERR(pm->asb))
+			return PTR_ERR(pm->asb);
+
+		ret = devm_mfd_add_devices(dev, -1,
+					   bcm2835_power_devs,
+					   ARRAY_SIZE(bcm2835_power_devs),
+					   NULL, 0, NULL);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id bcm2835_pm_of_match[] = {
+	{ .compatible = "brcm,bcm2835-pm-wdt", },
+	{ .compatible = "brcm,bcm2835-pm", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
+
+static struct platform_driver bcm2835_pm_driver = {
+	.probe		= bcm2835_pm_probe,
+	.driver = {
+		.name =	"bcm2835-pm",
+		.of_match_table = bcm2835_pm_of_match,
+	},
+};
+module_platform_driver(bcm2835_pm_driver);
+
+MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
+MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");
+MODULE_LICENSE("GPL");