[PATCH 2/2] uio: add an of_genirq driver

[Wolfram Sang <w.sang@pengutronix.de>]

Picking up the now exported generic probe function from the
platform-variant of this driver, this patch adds an of-version. Also add
the binding documentation.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Hans J. Koch <hjk@linutronix.de>
Cc: Greg KH <gregkh@suse.de>
---

In probe, I put the resources-array on the stack to simplify the code. If this
is considered too huge for the stack (140 byte for a 32-bit system at the
moment), I can also post a version using kzalloc.

 Documentation/powerpc/dts-bindings/uio-generic.txt |   16 +++
 drivers/uio/Kconfig                                |    6 +
 drivers/uio/Makefile                               |    1 +
 drivers/uio/uio_of_genirq.c                        |   98 ++++++++++++++++++++
 4 files changed, 121 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/powerpc/dts-bindings/uio-generic.txt
 create mode 100644 drivers/uio/uio_of_genirq.c

diff --git a/Documentation/powerpc/dts-bindings/uio-generic.txt b/Documentation/powerpc/dts-bindings/uio-generic.txt
new file mode 100644
index 0000000..8ad9861
--- /dev/null
+++ b/Documentation/powerpc/dts-bindings/uio-generic.txt
@@ -0,0 +1,16 @@
+UIO for custom devices
+
+A device which will be mapped using the UIO subsystem.
+
+Properties:
+ - compatible : should contain the specific model used, followed by
+                "generic-uio".
+ - reg : address range(s) of the device (up to MAX_UIO_MAPS)
+ - interrupts : interrupt of the device
+
+Example:
+        c64fpga@0 {
+                compatible = "ptx,c64fpga001", "generic-uio";
+                reg = <0x0 0x10000>;
+                interrupts = <0 0 3>;
+        };
diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
index 7f86534..18efe38 100644
--- a/drivers/uio/Kconfig
+++ b/drivers/uio/Kconfig
@@ -46,6 +46,12 @@ config UIO_PDRV_GENIRQ
 
 	  If you don't know what to do here, say N.
 
+config UIO_OF_GENIRQ
+	tristate "Userspace I/O OF driver with generic IRQ handling"
+	depends on UIO_PDRV_GENIRQ && OF
+	help
+	  OF wrapper for the above platform driver.
+
 config UIO_SMX
 	tristate "SMX cryptengine UIO interface"
 	default n
diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
index 5c2586d..089fd56 100644
--- a/drivers/uio/Makefile
+++ b/drivers/uio/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_UIO)	+= uio.o
 obj-$(CONFIG_UIO_CIF)	+= uio_cif.o
 obj-$(CONFIG_UIO_PDRV)	+= uio_pdrv.o
 obj-$(CONFIG_UIO_PDRV_GENIRQ)	+= uio_pdrv_genirq.o
+obj-$(CONFIG_UIO_OF_GENIRQ)	+= uio_of_genirq.o
 obj-$(CONFIG_UIO_SMX)	+= uio_smx.o
 obj-$(CONFIG_UIO_AEC)	+= uio_aec.o
 obj-$(CONFIG_UIO_SERCOS3)	+= uio_sercos3.o
diff --git a/drivers/uio/uio_of_genirq.c b/drivers/uio/uio_of_genirq.c
new file mode 100644
index 0000000..254ec5b
--- /dev/null
+++ b/drivers/uio/uio_of_genirq.c
@@ -0,0 +1,98 @@
+/*
+ * OF wrapper to make use of the uio_pdrv_genirq-driver.
+ *
+ * Copyright (C) 2009 Wolfram Sang, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/uio_driver.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/uio_pdrv_genirq.h>
+
+#define OF_DRIVER_VERSION "1"
+
+static __devinit int uio_of_genirq_probe(struct of_device *op,
+		const struct of_device_id *match)
+{
+	struct uio_info *uioinfo;
+	struct resource resources[MAX_UIO_MAPS];
+	int i, ret;
+
+	uioinfo = kzalloc(sizeof(*uioinfo), GFP_KERNEL);
+	if (!uioinfo)
+		return -ENOMEM;
+
+	uioinfo->name = op->node->name;
+	uioinfo->version = OF_DRIVER_VERSION;
+	uioinfo->irq = irq_of_parse_and_map(op->node, 0);
+	if (!uioinfo->irq)
+		uioinfo->irq = UIO_IRQ_NONE;
+
+	for (i = 0; i < MAX_UIO_MAPS; ++i)
+		if (of_address_to_resource(op->node, i, &resources[i]))
+			break;
+
+	ret = __uio_pdrv_genirq_probe(&op->dev, uioinfo, &resources, i);
+	if (ret)
+		goto err_cleanup;
+
+	return 0;
+
+err_cleanup:
+	if (uioinfo->irq != UIO_IRQ_NONE)
+		irq_dispose_mapping(uioinfo->irq);
+
+	kfree(uioinfo);
+	return ret;
+}
+
+static __devexit int uio_of_genirq_remove(struct of_device *op)
+{
+	struct uio_pdrv_genirq_platdata *priv = dev_get_drvdata(&op->dev);
+
+	uio_unregister_device(priv->uioinfo);
+
+	if (priv->uioinfo->irq != UIO_IRQ_NONE)
+		irq_dispose_mapping(priv->uioinfo->irq);
+
+	kfree(priv->uioinfo);
+	kfree(priv);
+	return 0;
+}
+
+/* Match table for of_platform binding */
+static const struct of_device_id __devinitconst uio_of_genirq_match[] = {
+	{ .compatible = "generic-uio", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, uio_of_genirq_match);
+
+static struct of_platform_driver uio_of_genirq_driver = {
+	.owner = THIS_MODULE,
+	.name = "uio-of-genirq",
+	.match_table = uio_of_genirq_match,
+	.probe = uio_of_genirq_probe,
+	.remove = __devexit_p(uio_of_genirq_remove),
+};
+
+static inline int __init uio_of_genirq_init(void)
+{
+	return of_register_platform_driver(&uio_of_genirq_driver);
+}
+module_init(uio_of_genirq_init);
+
+static inline void __exit uio_of_genirq_exit(void)
+{
+	of_unregister_platform_driver(&uio_of_genirq_driver);
+}
+module_exit(uio_of_genirq_exit);
+
+MODULE_AUTHOR("Wolfram Sang");
+MODULE_DESCRIPTION("Userspace I/O OF driver with generic IRQ handling");
+MODULE_LICENSE("GPL v2");
-- 
1.6.3.1