1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * PM MFD driver for Broadcom BCM2835
  4 *
  5 * This driver binds to the PM block and creates the MFD device for
  6 * the WDT and power drivers.
  7 */
  8
  9#include <linux/delay.h>
 10#include <linux/io.h>
 11#include <linux/mfd/bcm2835-pm.h>
 12#include <linux/mfd/core.h>
 13#include <linux/module.h>
 14#include <linux/of_address.h>
 15#include <linux/of_platform.h>
 16#include <linux/platform_device.h>
 17#include <linux/types.h>
 18#include <linux/watchdog.h>
 19
 20static const struct mfd_cell bcm2835_pm_devs[] = {
 21	{ .name = "bcm2835-wdt" },
 22};
 23
 24static const struct mfd_cell bcm2835_power_devs[] = {
 25	{ .name = "bcm2835-power" },
 26};
 27
 28static int bcm2835_pm_get_pdata(struct platform_device *pdev,
 29				struct bcm2835_pm *pm)
 30{
 31	if (of_property_present(pm->dev->of_node, "reg-names")) {
 32		struct resource *res;
 33
 34		pm->base = devm_platform_ioremap_resource_byname(pdev, "pm");
 35		if (IS_ERR(pm->base))
 36			return PTR_ERR(pm->base);
 37
 38		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "asb");
 39		if (res) {
 40			pm->asb = devm_ioremap_resource(&pdev->dev, res);
 41			if (IS_ERR(pm->asb))
 42				pm->asb = NULL;
 43		}
 44
 45		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
 46						    "rpivid_asb");
 47		if (res) {
 48			pm->rpivid_asb = devm_ioremap_resource(&pdev->dev, res);
 49			if (IS_ERR(pm->rpivid_asb))
 50				pm->rpivid_asb = NULL;
 51		}
 52
 53		return 0;
 54	}
 55
 56	/* If no 'reg-names' property is found we can assume we're using old DTB. */
 57	pm->base = devm_platform_ioremap_resource(pdev, 0);
 58	if (IS_ERR(pm->base))
 59		return PTR_ERR(pm->base);
 60
 61	pm->asb = devm_platform_ioremap_resource(pdev, 1);
 62	if (IS_ERR(pm->asb))
 63		pm->asb = NULL;
 64
 65	pm->rpivid_asb = devm_platform_ioremap_resource(pdev, 2);
 66	if (IS_ERR(pm->rpivid_asb))
 67		pm->rpivid_asb = NULL;
 68
 69	return 0;
 70}
 71
 72static int bcm2835_pm_probe(struct platform_device *pdev)
 73{
 74	struct device *dev = &pdev->dev;
 75	struct bcm2835_pm *pm;
 76	int ret;
 77
 78	pm = devm_kzalloc(dev, sizeof(*pm), GFP_KERNEL);
 79	if (!pm)
 80		return -ENOMEM;
 81	platform_set_drvdata(pdev, pm);
 82
 83	pm->dev = dev;
 84
 85	ret = bcm2835_pm_get_pdata(pdev, pm);
 86	if (ret)
 87		return ret;
 88
 89	ret = devm_mfd_add_devices(dev, -1,
 90				   bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
 91				   NULL, 0, NULL);
 92	if (ret)
 93		return ret;
 94
 95	/*
 96	 * We'll use the presence of the AXI ASB regs in the
 97	 * bcm2835-pm binding as the key for whether we can reference
 98	 * the full PM register range and support power domains.
 99	 */
100	if (pm->asb)
101		return devm_mfd_add_devices(dev, -1, bcm2835_power_devs,
102					    ARRAY_SIZE(bcm2835_power_devs),
103					    NULL, 0, NULL);
104	return 0;
105}
106
107static const struct of_device_id bcm2835_pm_of_match[] = {
108	{ .compatible = "brcm,bcm2835-pm-wdt", },
109	{ .compatible = "brcm,bcm2835-pm", },
110	{ .compatible = "brcm,bcm2711-pm", },
111	{},
112};
113MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
114
115static struct platform_driver bcm2835_pm_driver = {
116	.probe		= bcm2835_pm_probe,
117	.driver = {
118		.name =	"bcm2835-pm",
119		.of_match_table = bcm2835_pm_of_match,
120	},
121};
122module_platform_driver(bcm2835_pm_driver);
123
124MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
125MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");