drivers/firmware/imx/sm-misc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2024 NXP
   4  */
   5
   6 #include <linux/firmware/imx/sm.h>
   7 #include <linux/module.h>
   8 #include <linux/of.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/scmi_protocol.h>
  11 #include <linux/scmi_imx_protocol.h>
  12
  13 static const struct scmi_imx_misc_proto_ops *imx_misc_ctrl_ops;
  14 static struct scmi_protocol_handle *ph;
  15 struct notifier_block scmi_imx_misc_ctrl_nb;
  16
  17 int scmi_imx_misc_ctrl_set(u32 id, u32 val)
  18 {
  19         if (!ph)
  20                 return -EPROBE_DEFER;
  21
  22         return imx_misc_ctrl_ops->misc_ctrl_set(ph, id, 1, &val);
  23 };
  24 EXPORT_SYMBOL(scmi_imx_misc_ctrl_set);
  25
  26 int scmi_imx_misc_ctrl_get(u32 id, u32 *num, u32 *val)
  27 {
  28         if (!ph)
  29                 return -EPROBE_DEFER;
  30
  31         return imx_misc_ctrl_ops->misc_ctrl_get(ph, id, num, val);
  32 }
  33 EXPORT_SYMBOL(scmi_imx_misc_ctrl_get);
  34
  35 static int scmi_imx_misc_ctrl_notifier(struct notifier_block *nb,
  36                                        unsigned long event, void *data)
  37 {
  38         /*
  39          * notifier_chain_register requires a valid notifier_block and
  40          * valid notifier_call. SCMI_EVENT_IMX_MISC_CONTROL is needed
  41          * to let SCMI firmware enable control events, but the hook here
  42          * is just a dummy function to avoid kernel panic as of now.
  43          */
  44         return 0;
  45 }
  46
  47 static int scmi_imx_misc_ctrl_probe(struct scmi_device *sdev)
  48 {
  49         const struct scmi_handle *handle = sdev->handle;
  50         struct device_node *np = sdev->dev.of_node;
  51         u32 src_id, flags;
  52         int ret, i, num;
  53
  54         if (!handle)
  55                 return -ENODEV;
  56
  57         if (imx_misc_ctrl_ops) {
  58                 dev_err(&sdev->dev, "misc ctrl already initialized\n");
  59                 return -EEXIST;
  60         }
  61
  62         imx_misc_ctrl_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_IMX_MISC, &ph);
  63         if (IS_ERR(imx_misc_ctrl_ops))
  64                 return PTR_ERR(imx_misc_ctrl_ops);
  65
  66         num = of_property_count_u32_elems(np, "nxp,ctrl-ids");
  67         if (num % 2) {
  68                 dev_err(&sdev->dev, "Invalid wakeup-sources\n");
  69                 return -EINVAL;
  70         }
  71
  72         scmi_imx_misc_ctrl_nb.notifier_call = &scmi_imx_misc_ctrl_notifier;
  73         for (i = 0; i < num; i += 2) {
  74                 ret = of_property_read_u32_index(np, "nxp,ctrl-ids", i, &src_id);
  75                 if (ret) {
  76                         dev_err(&sdev->dev, "Failed to read ctrl-id: %i\n", i);
  77                         continue;
  78                 }
  79
  80                 ret = of_property_read_u32_index(np, "nxp,ctrl-ids", i + 1, &flags);
  81                 if (ret) {
  82                         dev_err(&sdev->dev, "Failed to read ctrl-id value: %d\n", i + 1);
  83                         continue;
  84                 }
  85
  86                 ret = handle->notify_ops->devm_event_notifier_register(sdev, SCMI_PROTOCOL_IMX_MISC,
  87                                                                        SCMI_EVENT_IMX_MISC_CONTROL,
  88                                                                        &src_id,
  89                                                                        &scmi_imx_misc_ctrl_nb);
  90                 if (ret) {
  91                         dev_err(&sdev->dev, "Failed to register scmi misc event: %d\n", src_id);
  92                 } else {
  93                         ret = imx_misc_ctrl_ops->misc_ctrl_req_notify(ph, src_id,
  94                                                                       SCMI_EVENT_IMX_MISC_CONTROL,
  95                                                                       flags);
  96                         if (ret)
  97                                 dev_err(&sdev->dev, "Failed to req notify: %d\n", src_id);
  98                 }
  99         }
 100
 101         return 0;
 102 }
 103
 104 static const struct scmi_device_id scmi_id_table[] = {
 105         { SCMI_PROTOCOL_IMX_MISC, "imx-misc-ctrl" },
 106         { },
 107 };
 108 MODULE_DEVICE_TABLE(scmi, scmi_id_table);
 109
 110 static struct scmi_driver scmi_imx_misc_ctrl_driver = {
 111         .name = "scmi-imx-misc-ctrl",
 112         .probe = scmi_imx_misc_ctrl_probe,
 113         .id_table = scmi_id_table,
 114 };
 115 module_scmi_driver(scmi_imx_misc_ctrl_driver);
 116
 117 MODULE_AUTHOR("Peng Fan <[email protected]>");
 118 MODULE_DESCRIPTION("IMX SM MISC driver");
 119 MODULE_LICENSE("GPL");