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authorAndreas Larsson <andreas@gaisler.com>2013-04-17 14:36:50 +0200
committerLinus Walleij <linus.walleij@linaro.org>2013-04-26 08:50:27 +0200
commitddb27f3bf771b53e0e7aa93d0186ea5c03381e23 (patch)
tree19202eaf7b0e2d215c156e86992714f67ce804cc /drivers/gpio/gpio-grgpio.c
parent12028d2d216220618f76284af5f8ed510b11da55 (diff)
gpio: grgpio: Add device driver for GRGPIO cores
This driver supports GRGPIO gpio cores available in the GRLIB VHDL IP core library from Aeroflex Gaisler. Signed-off-by: Andreas Larsson <andreas@gaisler.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpio-grgpio.c')
-rw-r--r--drivers/gpio/gpio-grgpio.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-grgpio.c b/drivers/gpio/gpio-grgpio.c
new file mode 100644
index 000000000000..466a1c757fae
--- /dev/null
+++ b/drivers/gpio/gpio-grgpio.c
@@ -0,0 +1,149 @@
+/*
+ * Driver for Aeroflex Gaisler GRGPIO General Purpose I/O cores.
+ *
+ * 2013 (c) Aeroflex Gaisler AB
+ *
+ * This driver supports the GRGPIO GPIO core available in the GRLIB VHDL
+ * IP core library.
+ *
+ * Full documentation of the GRGPIO core can be found here:
+ * http://www.gaisler.com/products/grlib/grip.pdf
+ *
+ * See "Documentation/devicetree/bindings/gpio/gpio-grgpio.txt" for
+ * information on open firmware properties.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * Contributors: Andreas Larsson <andreas@gaisler.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/basic_mmio_gpio.h>
+
+#define GRGPIO_MAX_NGPIO 32
+
+#define GRGPIO_DATA 0x00
+#define GRGPIO_OUTPUT 0x04
+#define GRGPIO_DIR 0x08
+#define GRGPIO_IMASK 0x0c
+#define GRGPIO_IPOL 0x10
+#define GRGPIO_IEDGE 0x14
+#define GRGPIO_BYPASS 0x18
+#define GRGPIO_IMAP_BASE 0x20
+
+struct grgpio_priv {
+ struct bgpio_chip bgc;
+ void __iomem *regs;
+ struct device *dev;
+};
+
+static inline struct grgpio_priv *grgpio_gc_to_priv(struct gpio_chip *gc)
+{
+ struct bgpio_chip *bgc = to_bgpio_chip(gc);
+
+ return container_of(bgc, struct grgpio_priv, bgc);
+}
+
+static int grgpio_probe(struct platform_device *ofdev)
+{
+ struct device_node *np = ofdev->dev.of_node;
+ void __iomem *regs;
+ struct gpio_chip *gc;
+ struct bgpio_chip *bgc;
+ struct grgpio_priv *priv;
+ struct resource *res;
+ int err;
+ u32 prop;
+
+ priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
+ regs = devm_ioremap_resource(&ofdev->dev, res);
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ bgc = &priv->bgc;
+ err = bgpio_init(bgc, &ofdev->dev, 4, regs + GRGPIO_DATA,
+ regs + GRGPIO_OUTPUT, NULL, regs + GRGPIO_DIR, NULL,
+ BGPIOF_BIG_ENDIAN_BYTE_ORDER);
+ if (err) {
+ dev_err(&ofdev->dev, "bgpio_init() failed\n");
+ return err;
+ }
+
+ priv->regs = regs;
+ priv->dev = &ofdev->dev;
+
+ gc = &bgc->gc;
+ gc->of_node = np;
+ gc->owner = THIS_MODULE;
+ gc->label = np->full_name;
+ gc->base = -1;
+
+ err = of_property_read_u32(np, "nbits", &prop);
+ if (err || prop <= 0 || prop > GRGPIO_MAX_NGPIO) {
+ gc->ngpio = GRGPIO_MAX_NGPIO;
+ dev_dbg(&ofdev->dev,
+ "No or invalid nbits property: assume %d\n", gc->ngpio);
+ } else {
+ gc->ngpio = prop;
+ }
+
+ platform_set_drvdata(ofdev, priv);
+
+ err = gpiochip_add(gc);
+ if (err) {
+ dev_err(&ofdev->dev, "Could not add gpiochip\n");
+ return err;
+ }
+
+ dev_info(&ofdev->dev, "regs=0x%p, base=%d, ngpio=%d\n",
+ priv->regs, gc->base, gc->ngpio);
+
+ return 0;
+}
+
+static int grgpio_remove(struct platform_device *ofdev)
+{
+ struct grgpio_priv *priv = platform_get_drvdata(ofdev);
+
+ return gpiochip_remove(&priv->bgc.gc);
+}
+
+static struct of_device_id grgpio_match[] = {
+ {.name = "GAISLER_GPIO"},
+ {.name = "01_01a"},
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, grgpio_match);
+
+static struct platform_driver grgpio_driver = {
+ .driver = {
+ .name = "grgpio",
+ .owner = THIS_MODULE,
+ .of_match_table = grgpio_match,
+ },
+ .probe = grgpio_probe,
+ .remove = grgpio_remove,
+};
+module_platform_driver(grgpio_driver);
+
+MODULE_AUTHOR("Aeroflex Gaisler AB.");
+MODULE_DESCRIPTION("Driver for Aeroflex Gaisler GRGPIO");
+MODULE_LICENSE("GPL");