/*
 * Copyright (c) 2014 Google, Inc
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

#include <common.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <malloc.h>
#include <spi.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#include <dm/root.h>
#include <dm/lists.h>
#include <dm/util.h>

DECLARE_GLOBAL_DATA_PTR;

static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
{
        struct dm_spi_ops *ops;
        int ret;

        ops = spi_get_ops(bus);
        if (ops->set_speed)
                ret = ops->set_speed(bus, speed);
        else
                ret = -EINVAL;
        if (ret) {
                printf("Cannot set speed (err=%d)\n", ret);
                return ret;
        }

        if (ops->set_mode)
                ret = ops->set_mode(bus, mode);
        else
                ret = -EINVAL;
        if (ret) {
                printf("Cannot set mode (err=%d)\n", ret);
                return ret;
        }

        return 0;
}

int dm_spi_claim_bus(struct udevice *dev)
{
        struct udevice *bus = dev->parent;
        struct dm_spi_ops *ops = spi_get_ops(bus);
        struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
        struct spi_slave *slave = dev_get_parent_priv(dev);
        int speed;
        int ret;

        speed = slave->max_hz;
        if (spi->max_hz) {
                if (speed)
                        speed = min(speed, (int)spi->max_hz);
                else
                        speed = spi->max_hz;
        }
        if (!speed)
                speed = 100000;
        if (speed != slave->speed) {
                ret = spi_set_speed_mode(bus, speed, slave->mode);
                if (ret)
                        return ret;
                slave->speed = speed;
        }

        return ops->claim_bus ? ops->claim_bus(dev) : 0;
}

void dm_spi_release_bus(struct udevice *dev)
{
        struct udevice *bus = dev->parent;
        struct dm_spi_ops *ops = spi_get_ops(bus);

        if (ops->release_bus)
                ops->release_bus(dev);
}

int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
                const void *dout, void *din, unsigned long flags)
{
        struct udevice *bus = dev->parent;

        if (bus->uclass->uc_drv->id != UCLASS_SPI)
                return -EOPNOTSUPP;

        return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags);
}

int spi_claim_bus(struct spi_slave *slave)
{
        return dm_spi_claim_bus(slave->dev);
}

void spi_release_bus(struct spi_slave *slave)
{
        dm_spi_release_bus(slave->dev);
}

int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
             const void *dout, void *din, unsigned long flags)
{
        return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
}

static int spi_post_bind(struct udevice *dev)
{
        /* Scan the bus for devices */
        return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
}

static int spi_child_post_bind(struct udevice *dev)
{
        struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);

        if (dev->of_offset == -1)
                return 0;

        return spi_slave_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, plat);
}

static int spi_post_probe(struct udevice *bus)
{
        struct dm_spi_bus *spi = dev_get_uclass_priv(bus);

        spi->max_hz = fdtdec_get_int(gd->fdt_blob, bus->of_offset,
                                     "spi-max-frequency", 0);

#if defined(CONFIG_NEEDS_MANUAL_RELOC)
        struct dm_spi_ops *ops = spi_get_ops(bus);


        if (ops->claim_bus)
                ops->claim_bus += gd->reloc_off;
        if (ops->release_bus)
                ops->release_bus += gd->reloc_off;
        if (ops->set_wordlen)
                ops->set_wordlen += gd->reloc_off;
        if (ops->xfer)
                ops->xfer += gd->reloc_off;
        if (ops->set_speed)
                ops->set_speed += gd->reloc_off;
        if (ops->set_mode)
                ops->set_mode += gd->reloc_off;
        if (ops->cs_info)
                ops->cs_info += gd->reloc_off;
#endif

        return 0;
}

static int spi_child_pre_probe(struct udevice *dev)
{
        struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
        struct spi_slave *slave = dev_get_parent_priv(dev);

        /*
         * This is needed because we pass struct spi_slave around the place
         * instead slave->dev (a struct udevice). So we have to have some
         * way to access the slave udevice given struct spi_slave. Once we
         * change the SPI API to use udevice instead of spi_slave, we can
         * drop this.
         */
        slave->dev = dev;

        slave->max_hz = plat->max_hz;
        slave->mode = plat->mode;
        slave->mode_rx = plat->mode_rx;
        slave->wordlen = SPI_DEFAULT_WORDLEN;

        return 0;
}

int spi_chip_select(struct udevice *dev)
{
        struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);

        return plat ? plat->cs : -ENOENT;
}

int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
{
        struct udevice *dev;

        for (device_find_first_child(bus, &dev); dev;
             device_find_next_child(&dev)) {
                struct dm_spi_slave_platdata *plat;

                plat = dev_get_parent_platdata(dev);
                debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
                if (plat->cs == cs) {
                        *devp = dev;
                        return 0;
                }
        }

        return -ENODEV;
}

int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
{
        struct spi_cs_info info;
        struct udevice *bus;
        int ret;

        ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
        if (ret) {
                debug("%s: No bus %d\n", __func__, busnum);
                return ret;
        }

        return spi_cs_info(bus, cs, &info);
}

int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
{
        struct spi_cs_info local_info;
        struct dm_spi_ops *ops;
        int ret;

        if (!info)
                info = &local_info;

        /* If there is a device attached, return it */
        info->dev = NULL;
        ret = spi_find_chip_select(bus, cs, &info->dev);
        if (!ret)
                return 0;

        /*
         * Otherwise ask the driver. For the moment we don't have CS info.
         * When we do we could provide the driver with a helper function
         * to figure out what chip selects are valid, or just handle the
         * request.
         */
        ops = spi_get_ops(bus);
        if (ops->cs_info)
                return ops->cs_info(bus, cs, info);

        /*
         * We could assume there is at least one valid chip select, but best
         * to be sure and return an error in this case. The driver didn't
         * care enough to tell us.
         */
        return -ENODEV;
}

int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
                        struct udevice **devp)
{
        struct udevice *bus, *dev;
        int ret;

        ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
        if (ret) {
                debug("%s: No bus %d\n", __func__, busnum);
                return ret;
        }
        ret = spi_find_chip_select(bus, cs, &dev);
        if (ret) {
                debug("%s: No cs %d\n", __func__, cs);
                return ret;
        }
        *busp = bus;
        *devp = dev;

        return ret;
}

int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
                       const char *drv_name, const char *dev_name,
                       struct udevice **busp, struct spi_slave **devp)
{
        struct udevice *bus, *dev;
        bool created = false;
        int ret;

        ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
        if (ret) {
                printf("Invalid bus %d (err=%d)\n", busnum, ret);
                return ret;
        }
        ret = spi_find_chip_select(bus, cs, &dev);

        /*
         * If there is no such device, create one automatically. This means
         * that we don't need a device tree node or platform data for the
         * SPI flash chip - we will bind to the correct driver.
         */
        if (ret == -ENODEV && drv_name) {
                struct dm_spi_slave_platdata *plat;

                debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
                      __func__, dev_name, busnum, cs, drv_name);
                ret = device_bind_driver(bus, drv_name, dev_name, &dev);
                if (ret)
                        return ret;
                plat = dev_get_parent_platdata(dev);
                plat->cs = cs;
                plat->max_hz = speed;
                plat->mode = mode;
                created = true;
        } else if (ret) {
                printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
                       ret);
                return ret;
        }

        if (!device_active(dev)) {
                struct spi_slave *slave;

                ret = device_probe(dev);
                if (ret)
                        goto err;
                slave = dev_get_parent_priv(dev);
                slave->dev = dev;
        }

        ret = spi_set_speed_mode(bus, speed, mode);
        if (ret)
                goto err;

        *busp = bus;
        *devp = dev_get_parent_priv(dev);
        debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);

        return 0;

err:
        debug("%s: Error path, credted=%d, device '%s'\n", __func__,
              created, dev->name);
        if (created) {
                device_remove(dev);
                device_unbind(dev);
        }

        return ret;
}

/* Compatibility function - to be removed */
struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
                                      int bus_node)
{
        struct udevice *bus, *dev;
        int ret;

        ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus);
        if (ret)
                return NULL;
        ret = device_get_child_by_of_offset(bus, node, &dev);
        if (ret)
                return NULL;
        return dev_get_parent_priv(dev);
}

/* Compatibility function - to be removed */
struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
                                  unsigned int speed, unsigned int mode)
{
        struct spi_slave *slave;
        struct udevice *dev;
        int ret;

        ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
                                  &slave);
        if (ret)
                return NULL;

        return slave;
}

void spi_free_slave(struct spi_slave *slave)
{
        device_remove(slave->dev);
        slave->dev = NULL;
}

int spi_slave_ofdata_to_platdata(const void *blob, int node,
                                 struct dm_spi_slave_platdata *plat)
{
        int mode = 0, mode_rx = 0;
        int value;

        plat->cs = fdtdec_get_int(blob, node, "reg", -1);
        plat->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
        if (fdtdec_get_bool(blob, node, "spi-cpol"))
                mode |= SPI_CPOL;
        if (fdtdec_get_bool(blob, node, "spi-cpha"))
                mode |= SPI_CPHA;
        if (fdtdec_get_bool(blob, node, "spi-cs-high"))
                mode |= SPI_CS_HIGH;
        if (fdtdec_get_bool(blob, node, "spi-3wire"))
                mode |= SPI_3WIRE;
        if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
                mode |= SPI_PREAMBLE;

        /* Device DUAL/QUAD mode */
        value = fdtdec_get_uint(blob, node, "spi-tx-bus-width", 1);
        switch (value) {
        case 1:
                break;
        case 2:
                mode |= SPI_TX_DUAL;
                break;
        case 4:
                mode |= SPI_TX_QUAD;
                break;
        default:
                error("spi-tx-bus-width %d not supported\n", value);
                break;
        }

        plat->mode = mode;

        value = fdtdec_get_uint(blob, node, "spi-rx-bus-width", 1);
        switch (value) {
        case 1:
                break;
        case 2:
                mode_rx |= SPI_RX_DUAL;
                break;
        case 4:
                mode_rx |= SPI_RX_QUAD;
                break;
        default:
                error("spi-rx-bus-width %d not supported\n", value);
                break;
        }

        plat->mode_rx = mode_rx;

        return 0;
}

UCLASS_DRIVER(spi) = {
        .id             = UCLASS_SPI,
        .name           = "spi",
        .flags          = DM_UC_FLAG_SEQ_ALIAS,
        .post_bind      = spi_post_bind,
        .post_probe     = spi_post_probe,
        .child_pre_probe = spi_child_pre_probe,
        .per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
        .per_child_auto_alloc_size = sizeof(struct spi_slave),
        .per_child_platdata_auto_alloc_size =
                        sizeof(struct dm_spi_slave_platdata),
        .child_post_bind = spi_child_post_bind,
};

UCLASS_DRIVER(spi_generic) = {
        .id             = UCLASS_SPI_GENERIC,
        .name           = "spi_generic",
};

U_BOOT_DRIVER(spi_generic_drv) = {
        .name           = "spi_generic_drv",
        .id             = UCLASS_SPI_GENERIC,
};