root/drivers/mtd/nand/raw/fsl_upm.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Freescale UPM NAND driver.
 *
 * Copyright © 2007-2008  MontaVista Software, Inc.
 *
 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/mtd/rawnand.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/mtd.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <asm/fsl_lbc.h>

struct fsl_upm_nand {
        struct nand_controller base;
        struct device *dev;
        struct nand_chip chip;
        struct fsl_upm upm;
        uint8_t upm_addr_offset;
        uint8_t upm_cmd_offset;
        void __iomem *io_base;
        struct gpio_desc *rnb_gpio[NAND_MAX_CHIPS];
        uint32_t mchip_offsets[NAND_MAX_CHIPS];
        uint32_t mchip_count;
        uint32_t mchip_number;
};

static inline struct fsl_upm_nand *to_fsl_upm_nand(struct mtd_info *mtdinfo)
{
        return container_of(mtd_to_nand(mtdinfo), struct fsl_upm_nand,
                            chip);
}

static int fun_chip_init(struct fsl_upm_nand *fun,
                         const struct device_node *upm_np,
                         const struct resource *io_res)
{
        struct mtd_info *mtd = nand_to_mtd(&fun->chip);
        int ret;
        struct device_node *flash_np;

        fun->chip.ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
        fun->chip.ecc.algo = NAND_ECC_ALGO_HAMMING;
        fun->chip.controller = &fun->base;
        mtd->dev.parent = fun->dev;

        flash_np = of_get_next_child(upm_np, NULL);
        if (!flash_np)
                return -ENODEV;

        nand_set_flash_node(&fun->chip, flash_np);
        mtd->name = devm_kasprintf(fun->dev, GFP_KERNEL, "0x%llx.%pOFn",
                                   (u64)io_res->start,
                                   flash_np);
        if (!mtd->name) {
                ret = -ENOMEM;
                goto err;
        }

        ret = nand_scan(&fun->chip, fun->mchip_count);
        if (ret)
                goto err;

        ret = mtd_device_register(mtd, NULL, 0);
err:
        of_node_put(flash_np);
        return ret;
}

static int func_exec_instr(struct nand_chip *chip,
                           const struct nand_op_instr *instr)
{
        struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
        u32 mar, reg_offs = fun->mchip_offsets[fun->mchip_number];
        unsigned int i;
        const u8 *out;
        u8 *in;

        switch (instr->type) {
        case NAND_OP_CMD_INSTR:
                fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
                mar = (instr->ctx.cmd.opcode << (32 - fun->upm.width)) |
                      reg_offs;
                fsl_upm_run_pattern(&fun->upm, fun->io_base + reg_offs, mar);
                fsl_upm_end_pattern(&fun->upm);
                return 0;

        case NAND_OP_ADDR_INSTR:
                fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
                for (i = 0; i < instr->ctx.addr.naddrs; i++) {
                        mar = (instr->ctx.addr.addrs[i] << (32 - fun->upm.width)) |
                              reg_offs;
                        fsl_upm_run_pattern(&fun->upm, fun->io_base + reg_offs, mar);
                }
                fsl_upm_end_pattern(&fun->upm);
                return 0;

        case NAND_OP_DATA_IN_INSTR:
                in = instr->ctx.data.buf.in;
                for (i = 0; i < instr->ctx.data.len; i++)
                        in[i] = in_8(fun->io_base + reg_offs);
                return 0;

        case NAND_OP_DATA_OUT_INSTR:
                out = instr->ctx.data.buf.out;
                for (i = 0; i < instr->ctx.data.len; i++)
                        out_8(fun->io_base + reg_offs, out[i]);
                return 0;

        case NAND_OP_WAITRDY_INSTR:
                if (!fun->rnb_gpio[fun->mchip_number])
                        return nand_soft_waitrdy(chip, instr->ctx.waitrdy.timeout_ms);

                return nand_gpio_waitrdy(chip, fun->rnb_gpio[fun->mchip_number],
                                         instr->ctx.waitrdy.timeout_ms);

        default:
                return -EINVAL;
        }

        return 0;
}

static int fun_exec_op(struct nand_chip *chip, const struct nand_operation *op,
                       bool check_only)
{
        struct fsl_upm_nand *fun = to_fsl_upm_nand(nand_to_mtd(chip));
        unsigned int i;
        int ret;

        if (op->cs >= NAND_MAX_CHIPS)
                return -EINVAL;

        if (check_only)
                return 0;

        fun->mchip_number = op->cs;

        for (i = 0; i < op->ninstrs; i++) {
                ret = func_exec_instr(chip, &op->instrs[i]);
                if (ret)
                        return ret;

                if (op->instrs[i].delay_ns)
                        ndelay(op->instrs[i].delay_ns);
        }

        return 0;
}

static const struct nand_controller_ops fun_ops = {
        .exec_op = fun_exec_op,
};

static int fun_probe(struct platform_device *ofdev)
{
        struct fsl_upm_nand *fun;
        struct resource *io_res;
        const __be32 *prop;
        int ret;
        int size;
        int i;

        fun = devm_kzalloc(&ofdev->dev, sizeof(*fun), GFP_KERNEL);
        if (!fun)
                return -ENOMEM;

        fun->io_base = devm_platform_get_and_ioremap_resource(ofdev, 0, &io_res);
        if (IS_ERR(fun->io_base))
                return PTR_ERR(fun->io_base);

        ret = fsl_upm_find(io_res->start, &fun->upm);
        if (ret) {
                dev_err(&ofdev->dev, "can't find UPM\n");
                return ret;
        }

        prop = of_get_property(ofdev->dev.of_node, "fsl,upm-addr-offset",
                               &size);
        if (!prop || size != sizeof(uint32_t)) {
                dev_err(&ofdev->dev, "can't get UPM address offset\n");
                return -EINVAL;
        }
        fun->upm_addr_offset = *prop;

        prop = of_get_property(ofdev->dev.of_node, "fsl,upm-cmd-offset", &size);
        if (!prop || size != sizeof(uint32_t)) {
                dev_err(&ofdev->dev, "can't get UPM command offset\n");
                return -EINVAL;
        }
        fun->upm_cmd_offset = *prop;

        prop = of_get_property(ofdev->dev.of_node,
                               "fsl,upm-addr-line-cs-offsets", &size);
        if (prop && (size / sizeof(uint32_t)) > 0) {
                fun->mchip_count = size / sizeof(uint32_t);
                if (fun->mchip_count >= NAND_MAX_CHIPS) {
                        dev_err(&ofdev->dev, "too much multiple chips\n");
                        return -EINVAL;
                }
                for (i = 0; i < fun->mchip_count; i++)
                        fun->mchip_offsets[i] = be32_to_cpu(prop[i]);
        } else {
                fun->mchip_count = 1;
        }

        for (i = 0; i < fun->mchip_count; i++) {
                fun->rnb_gpio[i] = devm_gpiod_get_index_optional(&ofdev->dev,
                                                                 NULL, i,
                                                                 GPIOD_IN);
                if (IS_ERR(fun->rnb_gpio[i])) {
                        dev_err(&ofdev->dev, "RNB gpio #%d is invalid\n", i);
                        return PTR_ERR(fun->rnb_gpio[i]);
                }
        }

        nand_controller_init(&fun->base);
        fun->base.ops = &fun_ops;
        fun->dev = &ofdev->dev;

        ret = fun_chip_init(fun, ofdev->dev.of_node, io_res);
        if (ret)
                return ret;

        dev_set_drvdata(&ofdev->dev, fun);

        return 0;
}

static void fun_remove(struct platform_device *ofdev)
{
        struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
        struct nand_chip *chip = &fun->chip;
        struct mtd_info *mtd = nand_to_mtd(chip);
        int ret;

        ret = mtd_device_unregister(mtd);
        WARN_ON(ret);
        nand_cleanup(chip);
}

static const struct of_device_id of_fun_match[] = {
        { .compatible = "fsl,upm-nand" },
        {},
};
MODULE_DEVICE_TABLE(of, of_fun_match);

static struct platform_driver of_fun_driver = {
        .driver = {
                .name = "fsl,upm-nand",
                .of_match_table = of_fun_match,
        },
        .probe          = fun_probe,
        .remove         = fun_remove,
};

module_platform_driver(of_fun_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
                   "LocalBus User-Programmable Machine");