[ARM] 3568/2: netX: pointer fifo driver

Patch from Sascha Hauer

This patch adds support for the pointer FIFOs on netX.

Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-netx/pfifo.c b/arch/arm/mach-netx/pfifo.c
new file mode 100644
index 0000000..44dea61
--- /dev/null
+++ b/arch/arm/mach-netx/pfifo.c
@@ -0,0 +1,68 @@
+/*
+ * arch/arm/mach-netx/pfifo.c
+ *
+ * Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+
+#include <asm/io.h>
+#include <asm/hardware.h>
+#include <asm/arch/netx-regs.h>
+#include <asm/arch/pfifo.h>
+
+static DEFINE_MUTEX(pfifo_lock);
+
+static unsigned int pfifo_used = 0;
+
+int pfifo_request(unsigned int pfifo_mask)
+{
+	int err = 0;
+	unsigned int val;
+
+	mutex_lock(&pfifo_lock);
+
+	if (pfifo_mask & pfifo_used) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	pfifo_used |= pfifo_mask;
+
+	val = readl(NETX_PFIFO_RESET);
+	writel(val | pfifo_mask, NETX_PFIFO_RESET);
+	writel(val, NETX_PFIFO_RESET);
+
+out:
+	mutex_unlock(&pfifo_lock);
+	return err;
+}
+
+void pfifo_free(unsigned int pfifo_mask)
+{
+	mutex_lock(&pfifo_lock);
+	pfifo_used &= ~pfifo_mask;
+	mutex_unlock(&pfifo_lock);
+}
+
+EXPORT_SYMBOL(pfifo_push);
+EXPORT_SYMBOL(pfifo_pop);
+EXPORT_SYMBOL(pfifo_fill_level);
+EXPORT_SYMBOL(pfifo_empty);
+EXPORT_SYMBOL(pfifo_request);
+EXPORT_SYMBOL(pfifo_free);