drivers/interconnect/qcom/smd-rpm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * RPM over SMD communication wrapper for interconnects
   4  *
   5  * Copyright (C) 2019 Linaro Ltd
   6  * Author: Georgi Djakov <georgi.djakov@linaro.org>
   7  */
   8
   9 #include <linux/interconnect-provider.h>
  10 #include <linux/module.h>
  11 #include <linux/of.h>
  12 #include <linux/of_platform.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/soc/qcom/smd-rpm.h>
  15
  16 #include "smd-rpm.h"
  17
  18 #define RPM_KEY_BW              0x00007762
  19
  20 static struct qcom_smd_rpm *icc_smd_rpm;
  21
  22 struct icc_rpm_smd_req {
  23         __le32 key;
  24         __le32 nbytes;
  25         __le32 value;
  26 };
  27
  28 bool qcom_icc_rpm_smd_available(void)
  29 {
  30         return !!icc_smd_rpm;
  31 }
  32 EXPORT_SYMBOL_GPL(qcom_icc_rpm_smd_available);
  33
  34 int qcom_icc_rpm_smd_send(int ctx, int rsc_type, int id, u32 val)
  35 {
  36         struct icc_rpm_smd_req req = {
  37                 .key = cpu_to_le32(RPM_KEY_BW),
  38                 .nbytes = cpu_to_le32(sizeof(u32)),
  39                 .value = cpu_to_le32(val),
  40         };
  41
  42         return qcom_rpm_smd_write(icc_smd_rpm, ctx, rsc_type, id, &req,
  43                                   sizeof(req));
  44 }
  45 EXPORT_SYMBOL_GPL(qcom_icc_rpm_smd_send);
  46
  47 static int qcom_icc_rpm_smd_remove(struct platform_device *pdev)
  48 {
  49         icc_smd_rpm = NULL;
  50
  51         return 0;
  52 }
  53
  54 static int qcom_icc_rpm_smd_probe(struct platform_device *pdev)
  55 {
  56         icc_smd_rpm = dev_get_drvdata(pdev->dev.parent);
  57
  58         if (!icc_smd_rpm) {
  59                 dev_err(&pdev->dev, "unable to retrieve handle to RPM\n");
  60                 return -ENODEV;
  61         }
  62
  63         return 0;
  64 }
  65
  66 static struct platform_driver qcom_interconnect_rpm_smd_driver = {
  67         .driver = {
  68                 .name           = "icc_smd_rpm",
  69         },
  70         .probe = qcom_icc_rpm_smd_probe,
  71         .remove = qcom_icc_rpm_smd_remove,
  72 };
  73 module_platform_driver(qcom_interconnect_rpm_smd_driver);
  74 MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>");
  75 MODULE_DESCRIPTION("Qualcomm SMD RPM interconnect proxy driver");
  76 MODULE_LICENSE("GPL v2");
  77 MODULE_ALIAS("platform:icc_smd_rpm");