root/drivers/soc/qcom/qcom_gsbi.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2014, The Linux foundation. All rights reserved.
 */

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <dt-bindings/soc/qcom,gsbi.h>

#define GSBI_CTRL_REG           0x0000
#define GSBI_PROTOCOL_SHIFT     4
#define MAX_GSBI                12

#define TCSR_ADM_CRCI_BASE      0x70

struct crci_config {
        u32 num_rows;
        const u32 (*array)[MAX_GSBI];
};

static const u32 crci_ipq8064[][MAX_GSBI] = {
        {
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000c00, 0x003000, 0x00c000,
                0x030000, 0x0c0000, 0x300000, 0xc00000
        },
        {
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000c00, 0x003000, 0x00c000,
                0x030000, 0x0c0000, 0x300000, 0xc00000
        },
};

static const struct crci_config config_ipq8064 = {
        .num_rows = ARRAY_SIZE(crci_ipq8064),
        .array = crci_ipq8064,
};

static const unsigned int crci_apq8064[][MAX_GSBI] = {
        {
                0x001800, 0x006000, 0x000030, 0x0000c0,
                0x000300, 0x000400, 0x000000, 0x000000,
                0x000000, 0x000000, 0x000000, 0x000000
        },
        {
                0x000000, 0x000000, 0x000000, 0x000000,
                0x000000, 0x000020, 0x0000c0, 0x000000,
                0x000000, 0x000000, 0x000000, 0x000000
        },
};

static const struct crci_config config_apq8064 = {
        .num_rows = ARRAY_SIZE(crci_apq8064),
        .array = crci_apq8064,
};

static const unsigned int crci_msm8960[][MAX_GSBI] = {
        {
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000400, 0x000000, 0x000000,
                0x000000, 0x000000, 0x000000, 0x000000
        },
        {
                0x000000, 0x000000, 0x000000, 0x000000,
                0x000000, 0x000020, 0x0000c0, 0x000300,
                0x001800, 0x006000, 0x000000, 0x000000
        },
};

static const struct crci_config config_msm8960 = {
        .num_rows = ARRAY_SIZE(crci_msm8960),
        .array = crci_msm8960,
};

static const unsigned int crci_msm8660[][MAX_GSBI] = {
        {       /* ADM 0 - B */
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000c00, 0x003000, 0x00c000,
                0x030000, 0x0c0000, 0x300000, 0xc00000
        },
        {       /* ADM 0 - B */
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000c00, 0x003000, 0x00c000,
                0x030000, 0x0c0000, 0x300000, 0xc00000
        },
        {       /* ADM 1 - A */
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000c00, 0x003000, 0x00c000,
                0x030000, 0x0c0000, 0x300000, 0xc00000
        },
        {       /* ADM 1 - B */
                0x000003, 0x00000c, 0x000030, 0x0000c0,
                0x000300, 0x000c00, 0x003000, 0x00c000,
                0x030000, 0x0c0000, 0x300000, 0xc00000
        },
};

static const struct crci_config config_msm8660 = {
        .num_rows = ARRAY_SIZE(crci_msm8660),
        .array = crci_msm8660,
};

struct gsbi_info {
        struct clk *hclk;
        u32 mode;
        u32 crci;
        struct regmap *tcsr;
};

static const struct of_device_id tcsr_dt_match[] __maybe_unused = {
        { .compatible = "qcom,tcsr-ipq8064", .data = &config_ipq8064},
        { .compatible = "qcom,tcsr-apq8064", .data = &config_apq8064},
        { .compatible = "qcom,tcsr-msm8960", .data = &config_msm8960},
        { .compatible = "qcom,tcsr-msm8660", .data = &config_msm8660},
        { },
};

static int gsbi_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct device_node *tcsr_node;
        const struct of_device_id *match;
        void __iomem *base;
        struct gsbi_info *gsbi;
        int i;
        u32 mask, gsbi_num;
        const struct crci_config *config = NULL;

        gsbi = devm_kzalloc(&pdev->dev, sizeof(*gsbi), GFP_KERNEL);

        if (!gsbi)
                return -ENOMEM;

        base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(base))
                return PTR_ERR(base);

        /* get the tcsr node and setup the config and regmap */
        gsbi->tcsr = syscon_regmap_lookup_by_phandle(node, "syscon-tcsr");

        if (!IS_ERR(gsbi->tcsr)) {
                tcsr_node = of_parse_phandle(node, "syscon-tcsr", 0);
                if (tcsr_node) {
                        match = of_match_node(tcsr_dt_match, tcsr_node);
                        if (match)
                                config = match->data;
                        else
                                dev_warn(&pdev->dev, "no matching TCSR\n");

                        of_node_put(tcsr_node);
                }
        }

        if (of_property_read_u32(node, "cell-index", &gsbi_num)) {
                dev_err(&pdev->dev, "missing cell-index\n");
                return -EINVAL;
        }

        if (gsbi_num < 1 || gsbi_num > MAX_GSBI) {
                dev_err(&pdev->dev, "invalid cell-index\n");
                return -EINVAL;
        }

        if (of_property_read_u32(node, "qcom,mode", &gsbi->mode)) {
                dev_err(&pdev->dev, "missing mode configuration\n");
                return -EINVAL;
        }

        /* not required, so default to 0 if not present */
        of_property_read_u32(node, "qcom,crci", &gsbi->crci);

        dev_info(&pdev->dev, "GSBI port protocol: %d crci: %d\n",
                 gsbi->mode, gsbi->crci);
        gsbi->hclk = devm_clk_get_enabled(&pdev->dev, "iface");
        if (IS_ERR(gsbi->hclk))
                return PTR_ERR(gsbi->hclk);

        writel_relaxed((gsbi->mode << GSBI_PROTOCOL_SHIFT) | gsbi->crci,
                                base + GSBI_CTRL_REG);

        /*
         * modify tcsr to reflect mode and ADM CRCI mux
         * Each gsbi contains a pair of bits, one for RX and one for TX
         * SPI mode requires both bits cleared, otherwise they are set
         */
        if (config) {
                for (i = 0; i < config->num_rows; i++) {
                        mask = config->array[i][gsbi_num - 1];

                        if (gsbi->mode == GSBI_PROT_SPI)
                                regmap_update_bits(gsbi->tcsr,
                                        TCSR_ADM_CRCI_BASE + 4 * i, mask, 0);
                        else
                                regmap_update_bits(gsbi->tcsr,
                                        TCSR_ADM_CRCI_BASE + 4 * i, mask, mask);

                }
        }

        /* make sure the gsbi control write is not reordered */
        wmb();

        platform_set_drvdata(pdev, gsbi);

        return of_platform_populate(node, NULL, NULL, &pdev->dev);
}

static const struct of_device_id gsbi_dt_match[] = {
        { .compatible = "qcom,gsbi-v1.0.0", },
        { },
};

MODULE_DEVICE_TABLE(of, gsbi_dt_match);

static struct platform_driver gsbi_driver = {
        .driver = {
                .name           = "gsbi",
                .of_match_table = gsbi_dt_match,
        },
        .probe = gsbi_probe,
};

module_platform_driver(gsbi_driver);

MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
MODULE_DESCRIPTION("QCOM GSBI driver");
MODULE_LICENSE("GPL v2");