[PATCH v1 1/7] zorro: warp mfd: add the CS-Lab Warp multifunction parent

[Paolo Pisati <p.pisati@gmail.com>]

The Warp 1260 is an A1200 trapdoor accelerator whose single Zorro device
fronts several functions: an ARM co-processor reached through a
dual-port RAM window, and an IDE interface and an RTG display controller
that the 68k drives directly.
pata_cswarp claims the whole device for the IDE window alone, which
leaves no way for anything else on the board to get a driver.

Add a parent that owns the Zorro device and describes the functions as
mfd cells, starting with the IDE window as a "warp-pata" cell.

Only the window layout is described here; the dual-port RAM protocol
arrives with its first user.
pata_cswarp is converted in the next patch.

Signed-off-by: Paolo Pisati <p.pisati@gmail.com>
---
 MAINTAINERS              |  7 ++++
 drivers/zorro/Kconfig    | 30 ++++++++++++++
 drivers/zorro/Makefile   |  2 +
 drivers/zorro/warp-mfd.c | 89 ++++++++++++++++++++++++++++++++++++++++
 drivers/zorro/warp-mfd.h | 19 +++++++++
 5 files changed, 147 insertions(+)
 create mode 100644 drivers/zorro/warp-mfd.c
 create mode 100644 drivers/zorro/warp-mfd.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 222b7fc2c3aa..cfabc4609c9d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7173,6 +7173,13 @@ L:	linux-crypto@vger.kernel.org
 S:	Maintained
 F:	tools/crypto/tcrypt/tcrypt_speed_compare.py
 
+CS-LAB WARP MULTIFUNCTION DRIVER
+M:	Paolo Pisati <p.pisati@gmail.com>
+L:	linux-m68k@lists.linux-m68k.org
+S:	Maintained
+F:	drivers/zorro/warp-mfd.c
+F:	drivers/zorro/warp-mfd.h
+
 CS3308 MEDIA DRIVER
 M:	Hans Verkuil <hverkuil@kernel.org>
 L:	linux-media@vger.kernel.org
diff --git a/drivers/zorro/Kconfig b/drivers/zorro/Kconfig
index 41475ad46e45..c9ab9fb4b9ee 100644
--- a/drivers/zorro/Kconfig
+++ b/drivers/zorro/Kconfig
@@ -17,3 +17,33 @@ config ZORRO_NAMES
 
 	  When in doubt, say Y.
 
+# Zorro multifunction drivers
+
+config WARP_MFD
+	tristate "CS-Lab Warp multifunction driver"
+	depends on ZORRO
+	select MFD_CORE
+	help
+	  The CS-Lab Warp 1260 is an A1200 trapdoor accelerator. Besides the
+	  68060 it carries an FPGA and an ARM co-processor; its control
+	  registers, the dual-port RAM and the IDE interface share one Zorro
+	  device, which this driver binds to.
+
+	  The 68k drives these through the FPGA: the on-board IDE interface and
+	  an RTG display controller.
+
+	  The co-processor owns the rest, reached over the dual-port RAM: two
+	  USB host ports, an SD card slot, an ESP32 WiFi bridge,
+	  an audio mixer, the Kickstart slot selection, the CPU clock and turbo
+	  levels, thermal regulation of the fan, and the board telemetry.
+
+	  This driver hands the IDE window to pata_cswarp - which needs
+	  idemode=native set in Warp Configuration to be of any use - and
+	  exposes the configuration and telemetry reachable over the dual-port
+	  RAM in sysfs: voltages, temperatures, fan, firmware version and
+	  Kickstart slot. Nothing else on the list has a driver yet.
+
+	  If you have a CS-Lab Warp 1260 board, say Y. Otherwise, say N.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called warp-mfd.
diff --git a/drivers/zorro/Makefile b/drivers/zorro/Makefile
index 91ba82e633e7..6fe7cc1822dc 100644
--- a/drivers/zorro/Makefile
+++ b/drivers/zorro/Makefile
@@ -7,6 +7,8 @@ obj-$(CONFIG_ZORRO)	+= zorro.o zorro-driver.o zorro-sysfs.o
 obj-$(CONFIG_PROC_FS)	+= proc.o
 obj-$(CONFIG_ZORRO_NAMES) +=  names.o
 
+obj-$(CONFIG_WARP_MFD) += warp-mfd.o
+
 hostprogs		:= gen-devlist
 
 # Files generated that shall be removed upon make clean
diff --git a/drivers/zorro/warp-mfd.c b/drivers/zorro/warp-mfd.c
new file mode 100644
index 000000000000..94af7c9d0ea5
--- /dev/null
+++ b/drivers/zorro/warp-mfd.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CS-Lab Warp multifunction driver
+ *
+ * Copyright 2026 Paolo Pisati <p.pisati@gmail.com>
+ *
+ * The Warp 1260 is an A1200 trapdoor accelerator made by CS-Lab. Besides the
+ * 68060 it carries an ARM co-processor which owns most of the peripherals,
+ * and the IDE interface and RTG display controller, which the 68k drives
+ * directly.
+ *
+ * This driver claims the Zorro device and hands the IDE window to pata_cswarp
+ * as an mfd cell.
+ */
+
+#include <linux/array_size.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+
+#include <linux/zorro.h>
+
+#include <linux/mfd/core.h>
+
+#include "warp-mfd.h"
+
+static const struct mfd_cell warp_mfd_cells[] = {
+	{
+		.name		= "warp-pata",
+		.num_resources  = 1,
+		.resources	= (const struct resource []) {
+			DEFINE_RES_MEM_NAMED(WARP_OFFSET_ATA, WARP_ATA_SIZE,
+					     "pata"),
+		}
+	}
+};
+
+static int warp_mfd_probe(struct zorro_dev *z,
+			  const struct zorro_device_id *ent)
+{
+	int error;
+
+	dev_info(&z->dev, "Warp at %pR\n", &z->resource);
+
+	error = mfd_add_devices(&z->dev, z->dev.id, warp_mfd_cells,
+				ARRAY_SIZE(warp_mfd_cells), &z->resource,
+				0, NULL);
+	if (error) {
+		dev_err(&z->dev, "mfd_add_devices() failed %d\n", error);
+		return error;
+	}
+	return 0;
+}
+
+static void warp_mfd_remove(struct zorro_dev *z)
+{
+	mfd_remove_devices(&z->dev);
+}
+
+static const struct zorro_device_id warp_mfd_ids[] = {
+	{ .id = ZORRO_PROD_CSLAB_WARP_1260 },
+	{ }
+};
+MODULE_DEVICE_TABLE(zorro, warp_mfd_ids);
+
+static struct zorro_driver warp_mfd_driver = {
+	.name		= "warp-mfd",
+	.id_table	= warp_mfd_ids,
+	.probe		= warp_mfd_probe,
+	.remove		= warp_mfd_remove
+};
+
+static int __init warp_mfd_init(void)
+{
+	return zorro_register_driver(&warp_mfd_driver);
+}
+
+static void __exit warp_mfd_exit(void)
+{
+	zorro_unregister_driver(&warp_mfd_driver);
+}
+
+module_init(warp_mfd_init);
+module_exit(warp_mfd_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paolo Pisati <p.pisati@gmail.com>");
+MODULE_DESCRIPTION("CS-Lab Warp multifunction driver");
diff --git a/drivers/zorro/warp-mfd.h b/drivers/zorro/warp-mfd.h
new file mode 100644
index 000000000000..3f44f2b57c76
--- /dev/null
+++ b/drivers/zorro/warp-mfd.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * CS-Lab Warp - board window layout
+ *
+ * Copyright 2026 Paolo Pisati <p.pisati@gmail.com>
+ */
+
+#ifndef _WARP_MFD_H
+#define _WARP_MFD_H
+
+/* Offsets from the start of the board's Zorro window. */
+#define WARP_OFFSET_DPREG_CR	0x1000	/* dual-port interrupt control reg */
+#define WARP_OFFSET_DPRAM	0x2000	/* dual-port RAM */
+#define WARP_OFFSET_ATA		0x6000	/* on-board IDE interface */
+
+#define WARP_DPRAM_SIZE		0x2000
+#define WARP_ATA_SIZE		0x1800
+
+#endif /* _WARP_MFD_H */
-- 
2.43.0