// SPDX-License-Identifier: GPL-2.0

#include <linux/mtd/spi-nor.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-mem.h>
#include <linux/sysfs.h>

#include "core.h"

static ssize_t manufacturer_show(struct device *dev,
                                 struct device_attribute *attr, char *buf)
{
        struct spi_device *spi = to_spi_device(dev);
        struct spi_mem *spimem = spi_get_drvdata(spi);
        struct spi_nor *nor = spi_mem_get_drvdata(spimem);

        return sysfs_emit(buf, "%s\n", nor->manufacturer->name);
}
static DEVICE_ATTR_RO(manufacturer);

static ssize_t partname_show(struct device *dev,
                             struct device_attribute *attr, char *buf)
{
        struct spi_device *spi = to_spi_device(dev);
        struct spi_mem *spimem = spi_get_drvdata(spi);
        struct spi_nor *nor = spi_mem_get_drvdata(spimem);

        return sysfs_emit(buf, "%s\n", nor->info->name);
}
static DEVICE_ATTR_RO(partname);

static ssize_t jedec_id_show(struct device *dev,
                             struct device_attribute *attr, char *buf)
{
        struct spi_device *spi = to_spi_device(dev);
        struct spi_mem *spimem = spi_get_drvdata(spi);
        struct spi_nor *nor = spi_mem_get_drvdata(spimem);
        const u8 *id = nor->info->id ? nor->info->id->bytes : nor->id;
        u8 id_len = nor->info->id ? nor->info->id->len : SPI_NOR_MAX_ID_LEN;

        return sysfs_emit(buf, "%*phN\n", id_len, id);
}
static DEVICE_ATTR_RO(jedec_id);

static struct attribute *spi_nor_sysfs_entries[] = {
        &dev_attr_manufacturer.attr,
        &dev_attr_partname.attr,
        &dev_attr_jedec_id.attr,
        NULL
};

static ssize_t sfdp_read(struct file *filp, struct kobject *kobj,
                         const struct bin_attribute *bin_attr, char *buf,
                         loff_t off, size_t count)
{
        struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
        struct spi_mem *spimem = spi_get_drvdata(spi);
        struct spi_nor *nor = spi_mem_get_drvdata(spimem);
        struct sfdp *sfdp = nor->sfdp;
        size_t sfdp_size = sfdp->num_dwords * sizeof(*sfdp->dwords);

        return memory_read_from_buffer(buf, count, &off, nor->sfdp->dwords,
                                       sfdp_size);
}
static const BIN_ATTR_RO(sfdp, 0);

static const struct bin_attribute *const spi_nor_sysfs_bin_entries[] = {
        &bin_attr_sfdp,
        NULL
};

static umode_t spi_nor_sysfs_is_visible(struct kobject *kobj,
                                        struct attribute *attr, int n)
{
        struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
        struct spi_mem *spimem = spi_get_drvdata(spi);
        struct spi_nor *nor = spi_mem_get_drvdata(spimem);

        if (attr == &dev_attr_manufacturer.attr && !nor->manufacturer)
                return 0;
        if (attr == &dev_attr_partname.attr && !nor->info->name)
                return 0;
        if (attr == &dev_attr_jedec_id.attr && !nor->info->id && !nor->id)
                return 0;

        return 0444;
}

static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj,
                                            const struct bin_attribute *attr, int n)
{
        struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
        struct spi_mem *spimem = spi_get_drvdata(spi);
        struct spi_nor *nor = spi_mem_get_drvdata(spimem);

        if (attr == &bin_attr_sfdp && nor->sfdp)
                return 0444;

        return 0;
}

static const struct attribute_group spi_nor_sysfs_group = {
        .name           = "spi-nor",
        .is_visible     = spi_nor_sysfs_is_visible,
        .is_bin_visible = spi_nor_sysfs_is_bin_visible,
        .attrs          = spi_nor_sysfs_entries,
        .bin_attrs      = spi_nor_sysfs_bin_entries,
};

const struct attribute_group *spi_nor_sysfs_groups[] = {
        &spi_nor_sysfs_group,
        NULL
};