v4.19.13 snapshot.
diff --git a/drivers/ide/ide-4drives.c b/drivers/ide/ide-4drives.c
new file mode 100644
index 0000000..547d7cf
--- /dev/null
+++ b/drivers/ide/ide-4drives.c
@@ -0,0 +1,64 @@
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/ide.h>
+
+#define DRV_NAME "ide-4drives"
+
+static bool probe_4drives;
+
+module_param_named(probe, probe_4drives, bool, 0);
+MODULE_PARM_DESC(probe, "probe for generic IDE chipset with 4 drives/port");
+
+static void ide_4drives_init_dev(ide_drive_t *drive)
+{
+ if (drive->hwif->channel)
+ drive->select ^= 0x20;
+}
+
+static const struct ide_port_ops ide_4drives_port_ops = {
+ .init_dev = ide_4drives_init_dev,
+};
+
+static const struct ide_port_info ide_4drives_port_info = {
+ .port_ops = &ide_4drives_port_ops,
+ .host_flags = IDE_HFLAG_SERIALIZE | IDE_HFLAG_NO_DMA |
+ IDE_HFLAG_4DRIVES,
+ .chipset = ide_4drives,
+};
+
+static int __init ide_4drives_init(void)
+{
+ unsigned long base = 0x1f0, ctl = 0x3f6;
+ struct ide_hw hw, *hws[] = { &hw, &hw };
+
+ if (probe_4drives == 0)
+ return -ENODEV;
+
+ if (!request_region(base, 8, DRV_NAME)) {
+ printk(KERN_ERR "%s: I/O resource 0x%lX-0x%lX not free.\n",
+ DRV_NAME, base, base + 7);
+ return -EBUSY;
+ }
+
+ if (!request_region(ctl, 1, DRV_NAME)) {
+ printk(KERN_ERR "%s: I/O resource 0x%lX not free.\n",
+ DRV_NAME, ctl);
+ release_region(base, 8);
+ return -EBUSY;
+ }
+
+ memset(&hw, 0, sizeof(hw));
+
+ ide_std_init_ports(&hw, base, ctl);
+ hw.irq = 14;
+
+ return ide_host_add(&ide_4drives_port_info, hws, 2, NULL);
+}
+
+module_init(ide_4drives_init);
+
+MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
+MODULE_DESCRIPTION("generic IDE chipset with 4 drives/port support");
+MODULE_LICENSE("GPL");