linux/drivers/mfd/bcm2835-pm.c
Rob Herring 1ba58fbbe6 mfd: various: Use of_property_present() for testing DT property presence
It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties. As
part of this, convert of_get_property/of_find_property calls to the
recently added of_property_present() helper when we just want to test
for presence of a property and nothing more.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230310144712.1543379-1-robh@kernel.org
2023-04-26 11:40:32 +01:00

126 lines
3.0 KiB
C

// 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_get_pdata(struct platform_device *pdev,
struct bcm2835_pm *pm)
{
if (of_property_present(pm->dev->of_node, "reg-names")) {
struct resource *res;
pm->base = devm_platform_ioremap_resource_byname(pdev, "pm");
if (IS_ERR(pm->base))
return PTR_ERR(pm->base);
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "asb");
if (res) {
pm->asb = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(pm->asb))
pm->asb = NULL;
}
res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
"rpivid_asb");
if (res) {
pm->rpivid_asb = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(pm->rpivid_asb))
pm->rpivid_asb = NULL;
}
return 0;
}
/* If no 'reg-names' property is found we can assume we're using old DTB. */
pm->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(pm->base))
return PTR_ERR(pm->base);
pm->asb = devm_platform_ioremap_resource(pdev, 1);
if (IS_ERR(pm->asb))
pm->asb = NULL;
pm->rpivid_asb = devm_platform_ioremap_resource(pdev, 2);
if (IS_ERR(pm->rpivid_asb))
pm->rpivid_asb = NULL;
return 0;
}
static int bcm2835_pm_probe(struct platform_device *pdev)
{
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;
ret = bcm2835_pm_get_pdata(pdev, pm);
if (ret)
return ret;
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.
*/
if (pm->asb)
return devm_mfd_add_devices(dev, -1, bcm2835_power_devs,
ARRAY_SIZE(bcm2835_power_devs),
NULL, 0, NULL);
return 0;
}
static const struct of_device_id bcm2835_pm_of_match[] = {
{ .compatible = "brcm,bcm2835-pm-wdt", },
{ .compatible = "brcm,bcm2835-pm", },
{ .compatible = "brcm,bcm2711-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");