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_get_pdata(struct platform_device * pdev,struct bcm2835_pm * pm)28 static int bcm2835_pm_get_pdata(struct platform_device *pdev,
29 struct bcm2835_pm *pm)
30 {
31 if (of_find_property(pm->dev->of_node, "reg-names", NULL)) {
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
bcm2835_pm_probe(struct platform_device * pdev)72 static 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
107 static 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 };
113 MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
114
115 static 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 };
122 module_platform_driver(bcm2835_pm_driver);
123
124 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
125 MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");
126 MODULE_LICENSE("GPL");
127