xref: /openbmc/linux/drivers/rtc/rtc-imx-sc.c (revision 8b030a57)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2018 NXP.
4  */
5 
6 #include <linux/firmware/imx/sci.h>
7 #include <linux/module.h>
8 #include <linux/of.h>
9 #include <linux/platform_device.h>
10 #include <linux/rtc.h>
11 
12 #define IMX_SC_TIMER_FUNC_GET_RTC_SEC1970	9
13 #define IMX_SC_TIMER_FUNC_SET_RTC_TIME		6
14 
15 static struct imx_sc_ipc *rtc_ipc_handle;
16 static struct rtc_device *imx_sc_rtc;
17 
18 struct imx_sc_msg_timer_get_rtc_time {
19 	struct imx_sc_rpc_msg hdr;
20 	u32 time;
21 } __packed;
22 
23 static int imx_sc_rtc_read_time(struct device *dev, struct rtc_time *tm)
24 {
25 	struct imx_sc_msg_timer_get_rtc_time msg;
26 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
27 	int ret;
28 
29 	hdr->ver = IMX_SC_RPC_VERSION;
30 	hdr->svc = IMX_SC_RPC_SVC_TIMER;
31 	hdr->func = IMX_SC_TIMER_FUNC_GET_RTC_SEC1970;
32 	hdr->size = 1;
33 
34 	ret = imx_scu_call_rpc(rtc_ipc_handle, &msg, true);
35 	if (ret) {
36 		dev_err(dev, "read rtc time failed, ret %d\n", ret);
37 		return ret;
38 	}
39 
40 	rtc_time_to_tm(msg.time, tm);
41 
42 	return 0;
43 }
44 
45 static const struct rtc_class_ops imx_sc_rtc_ops = {
46 	.read_time = imx_sc_rtc_read_time,
47 };
48 
49 static int imx_sc_rtc_probe(struct platform_device *pdev)
50 {
51 	int ret;
52 
53 	ret = imx_scu_get_handle(&rtc_ipc_handle);
54 	if (ret)
55 		return ret;
56 
57 	imx_sc_rtc = devm_rtc_allocate_device(&pdev->dev);
58 	if (IS_ERR(imx_sc_rtc))
59 		return PTR_ERR(imx_sc_rtc);
60 
61 	imx_sc_rtc->ops = &imx_sc_rtc_ops;
62 	imx_sc_rtc->range_min = 0;
63 	imx_sc_rtc->range_max = U32_MAX;
64 
65 	ret = rtc_register_device(imx_sc_rtc);
66 	if (ret) {
67 		dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
68 		return ret;
69 	}
70 
71 	return 0;
72 }
73 
74 static const struct of_device_id imx_sc_dt_ids[] = {
75 	{ .compatible = "fsl,imx8qxp-sc-rtc", },
76 	{}
77 };
78 MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);
79 
80 static struct platform_driver imx_sc_rtc_driver = {
81 	.driver = {
82 		.name	= "imx-sc-rtc",
83 		.of_match_table = imx_sc_dt_ids,
84 	},
85 	.probe		= imx_sc_rtc_probe,
86 };
87 module_platform_driver(imx_sc_rtc_driver);
88 
89 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
90 MODULE_DESCRIPTION("NXP i.MX System Controller RTC Driver");
91 MODULE_LICENSE("GPL");
92