drivers/rtc/rtc-imx-sc.c

   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");