// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Copyright (c) 2017, Linaro Ltd

   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/io.h>
  #include <linux/slab.h>
  #include <linux/of.h>
  #include <linux/of_platform.h>
  #include <linux/platform_device.h>

  #include <linux/regmap.h>

  #include <linux/mailbox_controller.h>
  
  #define QCOM_APCS_IPC_BITS	32
  
  struct qcom_apcs_ipc {
  	struct mbox_controller mbox;
  	struct mbox_chan mbox_chans[QCOM_APCS_IPC_BITS];

  	struct regmap *regmap;

  	unsigned long offset;

  	struct platform_device *clk;

  };

  struct qcom_apcs_ipc_data {
  	int offset;
  	char *clk_name;
  };

  static const struct qcom_apcs_ipc_data ipq6018_apcs_data = {
  	.offset = 8, .clk_name = "qcom,apss-ipq6018-clk"
  };

  static const struct qcom_apcs_ipc_data ipq8074_apcs_data = {
  	.offset = 8, .clk_name = NULL
  };
  
  static const struct qcom_apcs_ipc_data msm8916_apcs_data = {
  	.offset = 8, .clk_name = "qcom-apcs-msm8916-clk"
  };

  static const struct qcom_apcs_ipc_data msm8994_apcs_data = {
  	.offset = 8, .clk_name = NULL
  };

  static const struct qcom_apcs_ipc_data msm8996_apcs_data = {
  	.offset = 16, .clk_name = NULL
  };
  
  static const struct qcom_apcs_ipc_data msm8998_apcs_data = {
  	.offset = 8, .clk_name = NULL
  };

  static const struct qcom_apcs_ipc_data sdm660_apcs_data = {
  	.offset = 8, .clk_name = NULL
  };

  static const struct qcom_apcs_ipc_data apps_shared_apcs_data = {
  	.offset = 12, .clk_name = NULL
  };

  static const struct regmap_config apcs_regmap_config = {
  	.reg_bits = 32,
  	.reg_stride = 4,
  	.val_bits = 32,

  	.max_register = 0xFFC,

  	.fast_io = true,
  };

  static int qcom_apcs_ipc_send_data(struct mbox_chan *chan, void *data)
  {
  	struct qcom_apcs_ipc *apcs = container_of(chan->mbox,
  						  struct qcom_apcs_ipc, mbox);
  	unsigned long idx = (unsigned long)chan->con_priv;

  	return regmap_write(apcs->regmap, apcs->offset, BIT(idx));

  }
  
  static const struct mbox_chan_ops qcom_apcs_ipc_ops = {
  	.send_data = qcom_apcs_ipc_send_data,
  };
  
  static int qcom_apcs_ipc_probe(struct platform_device *pdev)
  {
  	struct qcom_apcs_ipc *apcs;

  	const struct qcom_apcs_ipc_data *apcs_data;

  	struct regmap *regmap;

  	struct resource *res;

  	void __iomem *base;
  	unsigned long i;
  	int ret;
  
  	apcs = devm_kzalloc(&pdev->dev, sizeof(*apcs), GFP_KERNEL);
  	if (!apcs)
  		return -ENOMEM;
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	base = devm_ioremap_resource(&pdev->dev, res);
  	if (IS_ERR(base))
  		return PTR_ERR(base);

  	regmap = devm_regmap_init_mmio(&pdev->dev, base, &apcs_regmap_config);
  	if (IS_ERR(regmap))
  		return PTR_ERR(regmap);

  	apcs_data = of_device_get_match_data(&pdev->dev);

  	apcs->regmap = regmap;

  	apcs->offset = apcs_data->offset;

  
  	/* Initialize channel identifiers */
  	for (i = 0; i < ARRAY_SIZE(apcs->mbox_chans); i++)
  		apcs->mbox_chans[i].con_priv = (void *)i;
  
  	apcs->mbox.dev = &pdev->dev;
  	apcs->mbox.ops = &qcom_apcs_ipc_ops;
  	apcs->mbox.chans = apcs->mbox_chans;
  	apcs->mbox.num_chans = ARRAY_SIZE(apcs->mbox_chans);

  	ret = devm_mbox_controller_register(&pdev->dev, &apcs->mbox);

  	if (ret) {
  		dev_err(&pdev->dev, "failed to register APCS IPC controller
  ");
  		return ret;
  	}

  	if (apcs_data->clk_name) {

  		apcs->clk = platform_device_register_data(&pdev->dev,

  							  apcs_data->clk_name,

  							  PLATFORM_DEVID_NONE,
  							  NULL, 0);

  		if (IS_ERR(apcs->clk))
  			dev_err(&pdev->dev, "failed to register APCS clk
  ");
  	}

  	platform_set_drvdata(pdev, apcs);
  
  	return 0;
  }
  
  static int qcom_apcs_ipc_remove(struct platform_device *pdev)
  {
  	struct qcom_apcs_ipc *apcs = platform_get_drvdata(pdev);

  	struct platform_device *clk = apcs->clk;

  	platform_device_unregister(clk);

  
  	return 0;
  }
  
  /* .data is the offset of the ipc register within the global block */
  static const struct of_device_id qcom_apcs_ipc_of_match[] = {

  	{ .compatible = "qcom,ipq6018-apcs-apps-global", .data = &ipq6018_apcs_data },

  	{ .compatible = "qcom,ipq8074-apcs-apps-global", .data = &ipq8074_apcs_data },
  	{ .compatible = "qcom,msm8916-apcs-kpss-global", .data = &msm8916_apcs_data },

  	{ .compatible = "qcom,msm8994-apcs-kpss-global", .data = &msm8994_apcs_data },

  	{ .compatible = "qcom,msm8996-apcs-hmss-global", .data = &msm8996_apcs_data },
  	{ .compatible = "qcom,msm8998-apcs-hmss-global", .data = &msm8998_apcs_data },
  	{ .compatible = "qcom,qcs404-apcs-apps-global", .data = &msm8916_apcs_data },
  	{ .compatible = "qcom,sc7180-apss-shared", .data = &apps_shared_apcs_data },

  	{ .compatible = "qcom,sdm660-apcs-hmss-global", .data = &sdm660_apcs_data },

  	{ .compatible = "qcom,sdm845-apss-shared", .data = &apps_shared_apcs_data },
  	{ .compatible = "qcom,sm8150-apss-shared", .data = &apps_shared_apcs_data },

  	{}
  };
  MODULE_DEVICE_TABLE(of, qcom_apcs_ipc_of_match);
  
  static struct platform_driver qcom_apcs_ipc_driver = {
  	.probe = qcom_apcs_ipc_probe,
  	.remove = qcom_apcs_ipc_remove,
  	.driver = {
  		.name = "qcom_apcs_ipc",
  		.of_match_table = qcom_apcs_ipc_of_match,
  	},
  };
  
  static int __init qcom_apcs_ipc_init(void)
  {
  	return platform_driver_register(&qcom_apcs_ipc_driver);
  }
  postcore_initcall(qcom_apcs_ipc_init);
  
  static void __exit qcom_apcs_ipc_exit(void)
  {
  	platform_driver_unregister(&qcom_apcs_ipc_driver);
  }
  module_exit(qcom_apcs_ipc_exit);
  
  MODULE_LICENSE("GPL v2");
  MODULE_DESCRIPTION("Qualcomm APCS IPC driver");