[neo] Every access to GPIO bank B has to go through the shadow code

    - Any setting of any PIN on bank B will undo the LED setting.
      Introduce neo1973_gpb_set_pin to set the PIN in a way not losing
      the LED or any other shadowed setting.
    - Update users of GPBXY for gta01 and gta02.

Signed-Off-By: Holger Freyther <zecke@openmoko.org>

1 files changed, 86 insertions, 0 deletions

diff --git a/arch/arm/plat-s3c24xx/neo1973_shadow.c b/arch/arm/plat-s3c24xx/neo1973_shadow.c
new file mode 100644
index 00000000000..09667da312b
--- /dev/null
+++ b/arch/arm/plat-s3c24xx/neo1973_shadow.c
@@ -0,0 +1,86 @@
+/*
+ * include/asm-arm/plat-s3c24xx/neo1973.h
+ *
+ * Common utility code for GTA01 and GTA02
+ *
+ * Copyright (C) 2008 by Openmoko, Inc.
+ * Author: Holger Hans Peter Freyther <freyther@openmoko.org>
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * 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/io.h>
+#include <linux/irq.h>
+
+#include <asm/gpio.h>
+#include <asm/plat-s3c24xx/neo1973.h>
+
+/**
+ * Shadow GPIO bank B handling. For the LEDs we need to keep track of the state
+ * in software. The s3c2410_gpio_setpin must not be used for GPIOs on bank B
+ */
+static unsigned long gpb_mask;
+static unsigned long gpb_state;
+
+void neo1973_gpb_add_shadow_gpio(unsigned int gpio)
+{
+	unsigned long offset = S3C2410_GPIO_OFFSET(gpio);
+	unsigned long flags;
+
+	local_irq_save(flags);
+	gpb_mask |= 1L << offset;
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(neo1973_gpb_add_shadow_gpio);
+
+static void set_shadow_gpio(unsigned long offset, unsigned int value)
+{
+	unsigned long state = value != 0;
+
+	gpb_state &= ~(1L << offset);
+	gpb_state |= state << offset;
+}
+
+void neo1973_gpb_setpin(unsigned int pin, unsigned to)
+{
+	void __iomem *base = S3C24XX_GPIO_BASE(S3C2410_GPB0);
+	unsigned long offset = S3C2410_GPIO_OFFSET(pin);
+	unsigned long flags;
+	unsigned long dat;
+
+	BUG_ON(base != S3C24XX_GPIO_BASE(pin));
+
+	local_irq_save(flags);
+	dat = __raw_readl(base + 0x04);
+
+	/* Add the shadow values */
+	dat &= ~gpb_mask;
+	dat |= gpb_state;
+
+	/* Do the operation like s3c2410_gpio_setpin */
+	dat &= ~(1L << offset);
+	dat |= to << offset;
+
+	/* Update the shadow state */
+	if ((1L << offset) & gpb_mask)
+		set_shadow_gpio(offset, to);
+
+	__raw_writel(dat, base + 0x04);
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(neo1973_gpb_setpin);