LXR linux/drivers/mailbox/qcom-apcs-ipc-mailbox.c

   1/*
   2 * Copyright (c) 2017, Linaro Ltd
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 and
   6 * only version 2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 * GNU General Public License for more details.
  12 */
  13
  14#include <linux/kernel.h>
  15#include <linux/module.h>
  16#include <linux/io.h>
  17#include <linux/slab.h>
  18#include <linux/of.h>
  19#include <linux/of_platform.h>
  20#include <linux/platform_device.h>
  21#include <linux/regmap.h>
  22#include <linux/mailbox_controller.h>
  23
  24#define QCOM_APCS_IPC_BITS      32
  25
  26struct qcom_apcs_ipc {
  27        struct mbox_controller mbox;
  28        struct mbox_chan mbox_chans[QCOM_APCS_IPC_BITS];
  29
  30        struct regmap *regmap;
  31        unsigned long offset;
  32        struct platform_device *clk;
  33};
  34
  35static const struct regmap_config apcs_regmap_config = {
  36        .reg_bits = 32,
  37        .reg_stride = 4,
  38        .val_bits = 32,
  39        .max_register = 0x1000,
  40        .fast_io = true,
  41};
  42
  43static int qcom_apcs_ipc_send_data(struct mbox_chan *chan, void *data)
  44{
  45        struct qcom_apcs_ipc *apcs = container_of(chan->mbox,
  46                                                  struct qcom_apcs_ipc, mbox);
  47        unsigned long idx = (unsigned long)chan->con_priv;
  48
  49        return regmap_write(apcs->regmap, apcs->offset, BIT(idx));
  50}
  51
  52static const struct mbox_chan_ops qcom_apcs_ipc_ops = {
  53        .send_data = qcom_apcs_ipc_send_data,
  54};
  55
  56static int qcom_apcs_ipc_probe(struct platform_device *pdev)
  57{
  58        struct device_node *np = pdev->dev.of_node;
  59        struct qcom_apcs_ipc *apcs;
  60        struct regmap *regmap;
  61        struct resource *res;
  62        unsigned long offset;
  63        void __iomem *base;
  64        unsigned long i;
  65        int ret;
  66
  67        apcs = devm_kzalloc(&pdev->dev, sizeof(*apcs), GFP_KERNEL);
  68        if (!apcs)
  69                return -ENOMEM;
  70
  71        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  72        base = devm_ioremap_resource(&pdev->dev, res);
  73        if (IS_ERR(base))
  74                return PTR_ERR(base);
  75
  76        regmap = devm_regmap_init_mmio(&pdev->dev, base, &apcs_regmap_config);
  77        if (IS_ERR(regmap))
  78                return PTR_ERR(regmap);
  79
  80        offset = (unsigned long)of_device_get_match_data(&pdev->dev);
  81
  82        apcs->regmap = regmap;
  83        apcs->offset = offset;
  84
  85        /* Initialize channel identifiers */
  86        for (i = 0; i < ARRAY_SIZE(apcs->mbox_chans); i++)
  87                apcs->mbox_chans[i].con_priv = (void *)i;
  88
  89        apcs->mbox.dev = &pdev->dev;
  90        apcs->mbox.ops = &qcom_apcs_ipc_ops;
  91        apcs->mbox.chans = apcs->mbox_chans;
  92        apcs->mbox.num_chans = ARRAY_SIZE(apcs->mbox_chans);
  93
  94        ret = mbox_controller_register(&apcs->mbox);
  95        if (ret) {
  96                dev_err(&pdev->dev, "failed to register APCS IPC controller\n");
  97                return ret;
  98        }
  99
 100        if (of_device_is_compatible(np, "qcom,msm8916-apcs-kpss-global")) {
 101                apcs->clk = platform_device_register_data(&pdev->dev,
 102                                                          "qcom-apcs-msm8916-clk",
 103                                                          -1, NULL, 0);
 104                if (IS_ERR(apcs->clk))
 105                        dev_err(&pdev->dev, "failed to register APCS clk\n");
 106        }
 107
 108        platform_set_drvdata(pdev, apcs);
 109
 110        return 0;
 111}
 112
 113static int qcom_apcs_ipc_remove(struct platform_device *pdev)
 114{
 115        struct qcom_apcs_ipc *apcs = platform_get_drvdata(pdev);
 116        struct platform_device *clk = apcs->clk;
 117
 118        mbox_controller_unregister(&apcs->mbox);
 119        platform_device_unregister(clk);
 120
 121        return 0;
 122}
 123
 124/* .data is the offset of the ipc register within the global block */
 125static const struct of_device_id qcom_apcs_ipc_of_match[] = {
 126        { .compatible = "qcom,msm8916-apcs-kpss-global", .data = (void *)8 },
 127        { .compatible = "qcom,msm8996-apcs-hmss-global", .data = (void *)16 },
 128        {}
 129};
 130MODULE_DEVICE_TABLE(of, qcom_apcs_ipc_of_match);
 131
 132static struct platform_driver qcom_apcs_ipc_driver = {
 133        .probe = qcom_apcs_ipc_probe,
 134        .remove = qcom_apcs_ipc_remove,
 135        .driver = {
 136                .name = "qcom_apcs_ipc",
 137                .of_match_table = qcom_apcs_ipc_of_match,
 138        },
 139};
 140
 141static int __init qcom_apcs_ipc_init(void)
 142{
 143        return platform_driver_register(&qcom_apcs_ipc_driver);
 144}
 145postcore_initcall(qcom_apcs_ipc_init);
 146
 147static void __exit qcom_apcs_ipc_exit(void)
 148{
 149        platform_driver_unregister(&qcom_apcs_ipc_driver);
 150}
 151module_exit(qcom_apcs_ipc_exit);
 152
 153MODULE_LICENSE("GPL v2");
 154MODULE_DESCRIPTION("Qualcomm APCS IPC driver");
 155