1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2018 Broadcom
4 */
5
6#include <linux/module.h>
7#include <linux/of_address.h>
8#include <linux/platform_device.h>
9#include <linux/thermal.h>
10
11/*
12 * In stingray thermal IO memory,
13 * Total Number of available TMONs MASK is at offset 0
14 * temperature registers BASE is at 4 byte offset.
15 * Each TMON temperature register size is 4.
16 */
17#define SR_TMON_TEMP_BASE(id)   ((id) * 0x4)
18
19#define SR_TMON_MAX_LIST        6
20
21struct sr_tmon {
22	unsigned int crit_temp;
23	unsigned int tmon_id;
24	struct sr_thermal *priv;
25};
26
27struct sr_thermal {
28	void __iomem *regs;
29	unsigned int max_crit_temp;
30	struct sr_tmon tmon[SR_TMON_MAX_LIST];
31};
32
33static int sr_get_temp(struct thermal_zone_device *tz, int *temp)
34{
35	struct sr_tmon *tmon = thermal_zone_device_priv(tz);
36	struct sr_thermal *sr_thermal = tmon->priv;
37
38	*temp = readl(sr_thermal->regs + SR_TMON_TEMP_BASE(tmon->tmon_id));
39
40	return 0;
41}
42
43static const struct thermal_zone_device_ops sr_tz_ops = {
44	.get_temp = sr_get_temp,
45};
46
47static int sr_thermal_probe(struct platform_device *pdev)
48{
49	struct device *dev = &pdev->dev;
50	struct thermal_zone_device *tz;
51	struct sr_thermal *sr_thermal;
52	struct sr_tmon *tmon;
53	struct resource *res;
54	u32 sr_tmon_list = 0;
55	unsigned int i;
56	int ret;
57
58	sr_thermal = devm_kzalloc(dev, sizeof(*sr_thermal), GFP_KERNEL);
59	if (!sr_thermal)
60		return -ENOMEM;
61
62	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
63	if (!res)
64		return -ENOENT;
65
66	sr_thermal->regs = (void __iomem *)devm_memremap(&pdev->dev, res->start,
67							 resource_size(res),
68							 MEMREMAP_WB);
69	if (IS_ERR(sr_thermal->regs)) {
70		dev_err(dev, "failed to get io address\n");
71		return PTR_ERR(sr_thermal->regs);
72	}
73
74	ret = device_property_read_u32(dev, "brcm,tmon-mask", &sr_tmon_list);
75	if (ret)
76		return ret;
77
78	tmon = sr_thermal->tmon;
79	for (i = 0; i < SR_TMON_MAX_LIST; i++, tmon++) {
80		if (!(sr_tmon_list & BIT(i)))
81			continue;
82
83		/* Flush temperature registers */
84		writel(0, sr_thermal->regs + SR_TMON_TEMP_BASE(i));
85		tmon->tmon_id = i;
86		tmon->priv = sr_thermal;
87		tz = devm_thermal_of_zone_register(dev, i, tmon,
88						   &sr_tz_ops);
89		if (IS_ERR(tz))
90			return PTR_ERR(tz);
91
92		dev_dbg(dev, "thermal sensor %d registered\n", i);
93	}
94
95	return 0;
96}
97
98static const struct of_device_id sr_thermal_of_match[] = {
99	{ .compatible = "brcm,sr-thermal", },
100	{},
101};
102MODULE_DEVICE_TABLE(of, sr_thermal_of_match);
103
104static struct platform_driver sr_thermal_driver = {
105	.probe		= sr_thermal_probe,
106	.driver = {
107		.name = "sr-thermal",
108		.of_match_table = sr_thermal_of_match,
109	},
110};
111module_platform_driver(sr_thermal_driver);
112
113MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
114MODULE_DESCRIPTION("Stingray thermal driver");
115MODULE_LICENSE("GPL v2");
116