LXR linux/drivers/mfd/bcm2835-pm.c

   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_probe(struct platform_device *pdev)
  29{
  30        struct resource *res;
  31        struct device *dev = &pdev->dev;
  32        struct bcm2835_pm *pm;
  33        int ret;
  34
  35        pm = devm_kzalloc(dev, sizeof(*pm), GFP_KERNEL);
  36        if (!pm)
  37                return -ENOMEM;
  38        platform_set_drvdata(pdev, pm);
  39
  40        pm->dev = dev;
  41
  42        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  43        pm->base = devm_ioremap_resource(dev, res);
  44        if (IS_ERR(pm->base))
  45                return PTR_ERR(pm->base);
  46
  47        ret = devm_mfd_add_devices(dev, -1,
  48                                   bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
  49                                   NULL, 0, NULL);
  50        if (ret)
  51                return ret;
  52
  53        /* We'll use the presence of the AXI ASB regs in the
  54         * bcm2835-pm binding as the key for whether we can reference
  55         * the full PM register range and support power domains.
  56         */
  57        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
  58        if (res) {
  59                pm->asb = devm_ioremap_resource(dev, res);
  60                if (IS_ERR(pm->asb))
  61                        return PTR_ERR(pm->asb);
  62
  63                ret = devm_mfd_add_devices(dev, -1,
  64                                           bcm2835_power_devs,
  65                                           ARRAY_SIZE(bcm2835_power_devs),
  66                                           NULL, 0, NULL);
  67                if (ret)
  68                        return ret;
  69        }
  70
  71        return 0;
  72}
  73
  74static const struct of_device_id bcm2835_pm_of_match[] = {
  75        { .compatible = "brcm,bcm2835-pm-wdt", },
  76        { .compatible = "brcm,bcm2835-pm", },
  77        {},
  78};
  79MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
  80
  81static struct platform_driver bcm2835_pm_driver = {
  82        .probe          = bcm2835_pm_probe,
  83        .driver = {
  84                .name = "bcm2835-pm",
  85                .of_match_table = bcm2835_pm_of_match,
  86        },
  87};
  88module_platform_driver(bcm2835_pm_driver);
  89
  90MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
  91MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");
  92MODULE_LICENSE("GPL");
  93