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
  26 struct 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
  35 static const struct regmap_config apcs_regmap_config = {
  36         .reg_bits = 32,
  37         .reg_stride = 4,
  38         .val_bits = 32,
  39         .max_register = 0xFFC,
  40         .fast_io = true,
  41 };
  42
  43 static 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
  52 static const struct mbox_chan_ops qcom_apcs_ipc_ops = {
  53         .send_data = qcom_apcs_ipc_send_data,
  54 };
  55
  56 static int qcom_apcs_ipc_probe(struct platform_device *pdev)
  57 {
  58         struct qcom_apcs_ipc *apcs;
  59         struct regmap *regmap;
  60         struct resource *res;
  61         unsigned long offset;
  62         void __iomem *base;
  63         unsigned long i;
  64         int ret;
  65         const struct of_device_id apcs_clk_match_table[] = {
  66                 { .compatible = "qcom,msm8916-apcs-kpss-global", },
  67                 { .compatible = "qcom,qcs404-apcs-apps-global", },
  68                 {}
  69         };
  70
  71         apcs = devm_kzalloc(&pdev->dev, sizeof(*apcs), GFP_KERNEL);
  72         if (!apcs)
  73                 return -ENOMEM;
  74
  75         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  76         base = devm_ioremap_resource(&pdev->dev, res);
  77         if (IS_ERR(base))
  78                 return PTR_ERR(base);
  79
  80         regmap = devm_regmap_init_mmio(&pdev->dev, base, &apcs_regmap_config);
  81         if (IS_ERR(regmap))
  82                 return PTR_ERR(regmap);
  83
  84         offset = (unsigned long)of_device_get_match_data(&pdev->dev);
  85
  86         apcs->regmap = regmap;
  87         apcs->offset = offset;
  88
  89         /* Initialize channel identifiers */
  90         for (i = 0; i < ARRAY_SIZE(apcs->mbox_chans); i++)
  91                 apcs->mbox_chans[i].con_priv = (void *)i;
  92
  93         apcs->mbox.dev = &pdev->dev;
  94         apcs->mbox.ops = &qcom_apcs_ipc_ops;
  95         apcs->mbox.chans = apcs->mbox_chans;
  96         apcs->mbox.num_chans = ARRAY_SIZE(apcs->mbox_chans);
  97
  98         ret = mbox_controller_register(&apcs->mbox);
  99         if (ret) {
 100                 dev_err(&pdev->dev, "failed to register APCS IPC controller\n");
 101                 return ret;
 102         }
 103
 104         if (of_match_device(apcs_clk_match_table, &pdev->dev)) {
 105                 apcs->clk = platform_device_register_data(&pdev->dev,
 106                                                           "qcom-apcs-msm8916-clk",
 107                                                           -1, NULL, 0);
 108                 if (IS_ERR(apcs->clk))
 109                         dev_err(&pdev->dev, "failed to register APCS clk\n");
 110         }
 111
 112         platform_set_drvdata(pdev, apcs);
 113
 114         return 0;
 115 }
 116
 117 static int qcom_apcs_ipc_remove(struct platform_device *pdev)
 118 {
 119         struct qcom_apcs_ipc *apcs = platform_get_drvdata(pdev);
 120         struct platform_device *clk = apcs->clk;
 121
 122         mbox_controller_unregister(&apcs->mbox);
 123         platform_device_unregister(clk);
 124
 125         return 0;
 126 }
 127
 128 /* .data is the offset of the ipc register within the global block */
 129 static const struct of_device_id qcom_apcs_ipc_of_match[] = {
 130         { .compatible = "qcom,msm8916-apcs-kpss-global", .data = (void *)8 },
 131         { .compatible = "qcom,msm8996-apcs-hmss-global", .data = (void *)16 },
 132         { .compatible = "qcom,msm8998-apcs-hmss-global", .data = (void *)8 },
 133         { .compatible = "qcom,sdm845-apss-shared", .data = (void *)12 },
 134         {}
 135 };
 136 MODULE_DEVICE_TABLE(of, qcom_apcs_ipc_of_match);
 137
 138 static struct platform_driver qcom_apcs_ipc_driver = {
 139         .probe = qcom_apcs_ipc_probe,
 140         .remove = qcom_apcs_ipc_remove,
 141         .driver = {
 142                 .name = "qcom_apcs_ipc",
 143                 .of_match_table = qcom_apcs_ipc_of_match,
 144         },
 145 };
 146
 147 static int __init qcom_apcs_ipc_init(void)
 148 {
 149         return platform_driver_register(&qcom_apcs_ipc_driver);
 150 }
 151 postcore_initcall(qcom_apcs_ipc_init);
 152
 153 static void __exit qcom_apcs_ipc_exit(void)
 154 {
 155         platform_driver_unregister(&qcom_apcs_ipc_driver);
 156 }
 157 module_exit(qcom_apcs_ipc_exit);
 158
 159 MODULE_LICENSE("GPL v2");
 160 MODULE_DESCRIPTION("Qualcomm APCS IPC driver");