// SPDX-License-Identifier: GPL-2.0-only
/*
 *    pata_jmicron.c - JMicron ATA driver for non AHCI mode. This drives the
 *                      PATA port of the controller. The SATA ports are
 *                      driven by AHCI in the usual configuration although
 *                      this driver can handle other setups if we need it.
 *
 *      (c) 2006 Red Hat
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/ata.h>

#define DRV_NAME        "pata_jmicron"
#define DRV_VERSION     "0.1.5"

typedef enum {
        PORT_PATA0 = 0,
        PORT_PATA1 = 1,
        PORT_SATA = 2,
} port_type;

/**
 *      jmicron_pre_reset       -       check for 40/80 pin
 *      @link: ATA link
 *      @deadline: deadline jiffies for the operation
 *
 *      Perform the PATA port setup we need.
 *
 *      On the Jmicron 361/363 there is a single PATA port that can be mapped
 *      either as primary or secondary (or neither). We don't do any policy
 *      and setup here. We assume that has been done by init_one and the
 *      BIOS.
 */
static int jmicron_pre_reset(struct ata_link *link, unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
        u32 control;
        u32 control5;
        int port_mask = 1<< (4 * ap->port_no);
        int port = ap->port_no;
        port_type port_map[2];

        /* Check if our port is enabled */
        pci_read_config_dword(pdev, 0x40, &control);
        if ((control & port_mask) == 0)
                return -ENOENT;

        /* There are two basic mappings. One has the two SATA ports merged
           as master/slave and the secondary as PATA, the other has only the
           SATA port mapped */
        if (control & (1 << 23)) {
                port_map[0] = PORT_SATA;
                port_map[1] = PORT_PATA0;
        } else {
                port_map[0] = PORT_SATA;
                port_map[1] = PORT_SATA;
        }

        /* The 365/366 may have this bit set to map the second PATA port
           as the internal primary channel */
        pci_read_config_dword(pdev, 0x80, &control5);
        if (control5 & (1<<24))
                port_map[0] = PORT_PATA1;

        /* The two ports may then be logically swapped by the firmware */
        if (control & (1 << 22))
                port = port ^ 1;

        /*
         *      Now we know which physical port we are talking about we can
         *      actually do our cable checking etc. Thankfully we don't need
         *      to do the plumbing for other cases.
         */
        switch (port_map[port]) {
        case PORT_PATA0:
                if ((control & (1 << 5)) == 0)
                        return -ENOENT;
                if (control & (1 << 3)) /* 40/80 pin primary */
                        ap->cbl = ATA_CBL_PATA40;
                else
                        ap->cbl = ATA_CBL_PATA80;
                break;
        case PORT_PATA1:
                /* Bit 21 is set if the port is enabled */
                if ((control5 & (1 << 21)) == 0)
                        return -ENOENT;
                if (control5 & (1 << 19))       /* 40/80 pin secondary */
                        ap->cbl = ATA_CBL_PATA40;
                else
                        ap->cbl = ATA_CBL_PATA80;
                break;
        case PORT_SATA:
                ap->cbl = ATA_CBL_SATA;
                break;
        }
        return ata_sff_prereset(link, deadline);
}

/* No PIO or DMA methods needed for this device */

static const struct scsi_host_template jmicron_sht = {
        ATA_BMDMA_SHT(DRV_NAME),
};

static struct ata_port_operations jmicron_ops = {
        .inherits               = &ata_bmdma_port_ops,
        .reset.prereset         = jmicron_pre_reset,
};


/**
 *      jmicron_init_one - Register Jmicron ATA PCI device with kernel services
 *      @pdev: PCI device to register
 *      @id: PCI device ID
 *
 *      Called from kernel PCI layer.
 *
 *      LOCKING:
 *      Inherited from PCI layer (may sleep).
 *
 *      RETURNS:
 *      Zero on success, or -ERRNO value.
 */

static int jmicron_init_one (struct pci_dev *pdev, const struct pci_device_id *id)
{
        static const struct ata_port_info info = {
                .flags  = ATA_FLAG_SLAVE_POSS,

                .pio_mask       = ATA_PIO4,
                .mwdma_mask     = ATA_MWDMA2,
                .udma_mask      = ATA_UDMA5,

                .port_ops       = &jmicron_ops,
        };
        const struct ata_port_info *ppi[] = { &info, NULL };

        return ata_pci_bmdma_init_one(pdev, ppi, &jmicron_sht, NULL, 0);
}

static const struct pci_device_id jmicron_pci_tbl[] = {
        { PCI_VENDOR_ID_JMICRON, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
          PCI_CLASS_STORAGE_IDE << 8, 0xffff00, 0 },
        { }     /* terminate list */
};

static struct pci_driver jmicron_pci_driver = {
        .name                   = DRV_NAME,
        .id_table               = jmicron_pci_tbl,
        .probe                  = jmicron_init_one,
        .remove                 = ata_pci_remove_one,
#ifdef CONFIG_PM_SLEEP
        .suspend                = ata_pci_device_suspend,
        .resume                 = ata_pci_device_resume,
#endif
};

module_pci_driver(jmicron_pci_driver);

MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("SCSI low-level driver for Jmicron PATA ports");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, jmicron_pci_tbl);
MODULE_VERSION(DRV_VERSION);