xref: /linux/drivers/rtc/rtc-imx-sc.c (revision 1f2367a39f17bd553a75e179a747f9b257bc9478)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2018 NXP.
4  */
5 
6 #include <linux/arm-smccc.h>
7 #include <linux/firmware/imx/sci.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/platform_device.h>
11 #include <linux/rtc.h>
12 
13 #define IMX_SC_TIMER_FUNC_GET_RTC_SEC1970	9
14 #define IMX_SC_TIMER_FUNC_SET_RTC_TIME		6
15 
16 #define IMX_SIP_SRTC			0xC2000002
17 #define IMX_SIP_SRTC_SET_TIME		0x0
18 
19 static struct imx_sc_ipc *rtc_ipc_handle;
20 static struct rtc_device *imx_sc_rtc;
21 
22 struct imx_sc_msg_timer_get_rtc_time {
23 	struct imx_sc_rpc_msg hdr;
24 	u32 time;
25 } __packed;
26 
27 static int imx_sc_rtc_read_time(struct device *dev, struct rtc_time *tm)
28 {
29 	struct imx_sc_msg_timer_get_rtc_time msg;
30 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
31 	int ret;
32 
33 	hdr->ver = IMX_SC_RPC_VERSION;
34 	hdr->svc = IMX_SC_RPC_SVC_TIMER;
35 	hdr->func = IMX_SC_TIMER_FUNC_GET_RTC_SEC1970;
36 	hdr->size = 1;
37 
38 	ret = imx_scu_call_rpc(rtc_ipc_handle, &msg, true);
39 	if (ret) {
40 		dev_err(dev, "read rtc time failed, ret %d\n", ret);
41 		return ret;
42 	}
43 
44 	rtc_time64_to_tm(msg.time, tm);
45 
46 	return 0;
47 }
48 
49 static int imx_sc_rtc_set_time(struct device *dev, struct rtc_time *tm)
50 {
51 	struct arm_smccc_res res;
52 
53 	/* pack 2 time parameters into 1 register, 16 bits for each */
54 	arm_smccc_smc(IMX_SIP_SRTC, IMX_SIP_SRTC_SET_TIME,
55 		      ((tm->tm_year + 1900) << 16) | (tm->tm_mon + 1),
56 		      (tm->tm_mday << 16) | tm->tm_hour,
57 		      (tm->tm_min << 16) | tm->tm_sec,
58 		      0, 0, 0, &res);
59 
60 	return res.a0;
61 }
62 
63 static const struct rtc_class_ops imx_sc_rtc_ops = {
64 	.read_time = imx_sc_rtc_read_time,
65 	.set_time = imx_sc_rtc_set_time,
66 };
67 
68 static int imx_sc_rtc_probe(struct platform_device *pdev)
69 {
70 	int ret;
71 
72 	ret = imx_scu_get_handle(&rtc_ipc_handle);
73 	if (ret)
74 		return ret;
75 
76 	imx_sc_rtc = devm_rtc_allocate_device(&pdev->dev);
77 	if (IS_ERR(imx_sc_rtc))
78 		return PTR_ERR(imx_sc_rtc);
79 
80 	imx_sc_rtc->ops = &imx_sc_rtc_ops;
81 	imx_sc_rtc->range_min = 0;
82 	imx_sc_rtc->range_max = U32_MAX;
83 
84 	ret = rtc_register_device(imx_sc_rtc);
85 	if (ret) {
86 		dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
87 		return ret;
88 	}
89 
90 	return 0;
91 }
92 
93 static const struct of_device_id imx_sc_dt_ids[] = {
94 	{ .compatible = "fsl,imx8qxp-sc-rtc", },
95 	{}
96 };
97 MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);
98 
99 static struct platform_driver imx_sc_rtc_driver = {
100 	.driver = {
101 		.name	= "imx-sc-rtc",
102 		.of_match_table = imx_sc_dt_ids,
103 	},
104 	.probe		= imx_sc_rtc_probe,
105 };
106 module_platform_driver(imx_sc_rtc_driver);
107 
108 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
109 MODULE_DESCRIPTION("NXP i.MX System Controller RTC Driver");
110 MODULE_LICENSE("GPL");
111