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 = 0x1000,
  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 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
 113 static 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 */
 125 static 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 };
 130 MODULE_DEVICE_TABLE(of, qcom_apcs_ipc_of_match);
 131
 132 static 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
 141 static int __init qcom_apcs_ipc_init(void)
 142 {
 143         return platform_driver_register(&qcom_apcs_ipc_driver);
 144 }
 145 postcore_initcall(qcom_apcs_ipc_init);
 146
 147 static void __exit qcom_apcs_ipc_exit(void)
 148 {
 149         platform_driver_unregister(&qcom_apcs_ipc_driver);
 150 }
 151 module_exit(qcom_apcs_ipc_exit);
 152
 153 MODULE_LICENSE("GPL v2");
 154 MODULE_DESCRIPTION("Qualcomm APCS IPC driver");