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
21 struct sr_tmon {
22 struct thermal_zone_device *tz;
23 unsigned int crit_temp;
24 unsigned int tmon_id;
25 struct sr_thermal *priv;
26 };
27
28 struct sr_thermal {
29 void __iomem *regs;
30 unsigned int max_crit_temp;
31 struct sr_tmon tmon[SR_TMON_MAX_LIST];
32 };
33
sr_get_temp(void * data,int * temp)34 static int sr_get_temp(void *data, int *temp)
35 {
36 struct sr_tmon *tmon = data;
37 struct sr_thermal *sr_thermal = tmon->priv;
38
39 *temp = readl(sr_thermal->regs + SR_TMON_TEMP_BASE(tmon->tmon_id));
40
41 return 0;
42 }
43
44 static const struct thermal_zone_of_device_ops sr_tz_ops = {
45 .get_temp = sr_get_temp,
46 };
47
sr_thermal_probe(struct platform_device * pdev)48 static int sr_thermal_probe(struct platform_device *pdev)
49 {
50 struct device *dev = &pdev->dev;
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 sr_thermal->regs = (void __iomem *)devm_memremap(&pdev->dev, res->start,
64 resource_size(res),
65 MEMREMAP_WB);
66 if (IS_ERR(sr_thermal->regs)) {
67 dev_err(dev, "failed to get io address\n");
68 return PTR_ERR(sr_thermal->regs);
69 }
70
71 ret = device_property_read_u32(dev, "brcm,tmon-mask", &sr_tmon_list);
72 if (ret)
73 return ret;
74
75 tmon = sr_thermal->tmon;
76 for (i = 0; i < SR_TMON_MAX_LIST; i++, tmon++) {
77 if (!(sr_tmon_list & BIT(i)))
78 continue;
79
80 /* Flush temperature registers */
81 writel(0, sr_thermal->regs + SR_TMON_TEMP_BASE(i));
82 tmon->tmon_id = i;
83 tmon->priv = sr_thermal;
84 tmon->tz = devm_thermal_zone_of_sensor_register(dev, i, tmon,
85 &sr_tz_ops);
86 if (IS_ERR(tmon->tz))
87 return PTR_ERR(tmon->tz);
88
89 dev_dbg(dev, "thermal sensor %d registered\n", i);
90 }
91 platform_set_drvdata(pdev, sr_thermal);
92
93 return 0;
94 }
95
96 static const struct of_device_id sr_thermal_of_match[] = {
97 { .compatible = "brcm,sr-thermal", },
98 {},
99 };
100 MODULE_DEVICE_TABLE(of, sr_thermal_of_match);
101
102 static struct platform_driver sr_thermal_driver = {
103 .probe = sr_thermal_probe,
104 .driver = {
105 .name = "sr-thermal",
106 .of_match_table = sr_thermal_of_match,
107 },
108 };
109 module_platform_driver(sr_thermal_driver);
110
111 MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
112 MODULE_DESCRIPTION("Stingray thermal driver");
113 MODULE_LICENSE("GPL v2");
114