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
20 static const struct mfd_cell bcm2835_pm_devs[] = {
21 { .name = "bcm2835-wdt" },
22 };
23
24 static const struct mfd_cell bcm2835_power_devs[] = {
25 { .name = "bcm2835-power" },
26 };
27
bcm2835_pm_probe(struct platform_device * pdev)28 static 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
74 static const struct of_device_id bcm2835_pm_of_match[] = {
75 { .compatible = "brcm,bcm2835-pm-wdt", },
76 { .compatible = "brcm,bcm2835-pm", },
77 {},
78 };
79 MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
80
81 static 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 };
88 module_platform_driver(bcm2835_pm_driver);
89
90 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
91 MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");
92 MODULE_LICENSE("GPL");
93