DA8xx: add generic GPIO driver

Add a generic GPIO driver for the DaVinci DA8xx processors. It is turned
on by defining CONFIG_DA8XX_GPIO and fulfills the generic GPIO interface
specified in <asm/gpio.h> . The driver has support for both manipulating
GPIO pins as well as automatically configuring the pin multiplexor
registers to set the pin function to GPIO.

Signed-off-by: Laurence Withers <lwithers@guralp.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

arch/arm/include/asm/arch-davinci/gpio.h

@@ -63,4 +63,12 @@ struct davinci_gpio_bank {
 #define davinci_gpio_bank45 ((struct davinci_gpio *)DAVINCI_GPIO_BANK45)
 #define davinci_gpio_bank67 ((struct davinci_gpio *)DAVINCI_GPIO_BANK67)
 
+#define gpio_status()		gpio_info()
+#define GPIO_NAME_SIZE		20
+#define MAX_NUM_GPIOS		144
+#define GPIO_BANK(gp)		(davinci_gpio_bank01 + ((gp) >> 5))
+#define GPIO_BIT(gp)		((gp) & 0x1F)
+
+void gpio_info(void);
+
 #endif

drivers/gpio/Makefile

@@ -32,6 +32,7 @@ COBJS-$(CONFIG_MXC_GPIO)	+= mxc_gpio.o
 COBJS-$(CONFIG_PCA953X)		+= pca953x.o
 COBJS-$(CONFIG_S5P)		+= s5p_gpio.o
 COBJS-$(CONFIG_TEGRA2_GPIO)	+= tegra2_gpio.o
+COBJS-$(CONFIG_DA8XX_GPIO)	+= da8xx_gpio.o
 
 COBJS	:= $(COBJS-y)
 SRCS 	:= $(COBJS:.o=.c)

drivers/gpio/da8xx_gpio.c

+/*
+ * GPIO driver for TI DaVinci DA8xx SOCs.
+ *
+ * (C) Copyright 2011 Guralp Systems Ltd.
+ * Laurence Withers <lwithers@guralp.com>
+ *
+ * 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 <common.h>
+#include <asm/io.h>
+#include <asm/gpio.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/davinci_misc.h>
+
+
+static struct gpio_registry {
+	int is_registered;
+	char name[GPIO_NAME_SIZE];
+} gpio_registry[MAX_NUM_GPIOS];
+
+
+#define pinmux(x)       (&davinci_syscfg_regs->pinmux[x])
+
+static const struct pinmux_config gpio_pinmux[] = {
+	{ pinmux(1), 8, 7 },	/* GP0[0] */
+	{ pinmux(1), 8, 6 },
+	{ pinmux(1), 8, 5 },
+	{ pinmux(1), 8, 4 },
+	{ pinmux(1), 8, 3 },
+	{ pinmux(1), 8, 2 },
+	{ pinmux(1), 8, 1 },
+	{ pinmux(1), 8, 0 },
+	{ pinmux(0), 8, 7 },
+	{ pinmux(0), 8, 6 },
+	{ pinmux(0), 8, 5 },
+	{ pinmux(0), 8, 4 },
+	{ pinmux(0), 8, 3 },
+	{ pinmux(0), 8, 2 },
+	{ pinmux(0), 8, 1 },
+	{ pinmux(0), 8, 0 },
+	{ pinmux(4), 8, 7 },	/* GP1[0] */
+	{ pinmux(4), 8, 6 },
+	{ pinmux(4), 8, 5 },
+	{ pinmux(4), 8, 4 },
+	{ pinmux(4), 8, 3 },
+	{ pinmux(4), 8, 2 },
+	{ pinmux(4), 4, 1 },
+	{ pinmux(4), 4, 0 },
+	{ pinmux(3), 4, 0 },
+	{ pinmux(2), 4, 6 },
+	{ pinmux(2), 4, 5 },
+	{ pinmux(2), 4, 4 },
+	{ pinmux(2), 4, 3 },
+	{ pinmux(2), 4, 2 },
+	{ pinmux(2), 4, 1 },
+	{ pinmux(2), 8, 0 },
+	{ pinmux(6), 8, 7 },	/* GP2[0] */
+	{ pinmux(6), 8, 6 },
+	{ pinmux(6), 8, 5 },
+	{ pinmux(6), 8, 4 },
+	{ pinmux(6), 8, 3 },
+	{ pinmux(6), 8, 2 },
+	{ pinmux(6), 8, 1 },
+	{ pinmux(6), 8, 0 },
+	{ pinmux(5), 8, 7 },
+	{ pinmux(5), 8, 6 },
+	{ pinmux(5), 8, 5 },
+	{ pinmux(5), 8, 4 },
+	{ pinmux(5), 8, 3 },
+	{ pinmux(5), 8, 2 },
+	{ pinmux(5), 8, 1 },
+	{ pinmux(5), 8, 0 },
+	{ pinmux(8), 8, 7 },	/* GP3[0] */
+	{ pinmux(8), 8, 6 },
+	{ pinmux(8), 8, 5 },
+	{ pinmux(8), 8, 4 },
+	{ pinmux(8), 8, 3 },
+	{ pinmux(8), 8, 2 },
+	{ pinmux(8), 8, 1 },
+	{ pinmux(8), 8, 0 },
+	{ pinmux(7), 8, 7 },
+	{ pinmux(7), 8, 6 },
+	{ pinmux(7), 8, 5 },
+	{ pinmux(7), 8, 4 },
+	{ pinmux(7), 8, 3 },
+	{ pinmux(7), 8, 2 },
+	{ pinmux(7), 8, 1 },
+	{ pinmux(7), 8, 0 },
+	{ pinmux(10), 8, 7 },	/* GP4[0] */
+	{ pinmux(10), 8, 6 },
+	{ pinmux(10), 8, 5 },
+	{ pinmux(10), 8, 4 },
+	{ pinmux(10), 8, 3 },
+	{ pinmux(10), 8, 2 },
+	{ pinmux(10), 8, 1 },
+	{ pinmux(10), 8, 0 },
+	{ pinmux(9), 8, 7 },
+	{ pinmux(9), 8, 6 },
+	{ pinmux(9), 8, 5 },
+	{ pinmux(9), 8, 4 },
+	{ pinmux(9), 8, 3 },
+	{ pinmux(9), 8, 2 },
+	{ pinmux(9), 8, 1 },
+	{ pinmux(9), 8, 0 },
+	{ pinmux(12), 8, 7 },	/* GP5[0] */
+	{ pinmux(12), 8, 6 },
+	{ pinmux(12), 8, 5 },
+	{ pinmux(12), 8, 4 },
+	{ pinmux(12), 8, 3 },
+	{ pinmux(12), 8, 2 },
+	{ pinmux(12), 8, 1 },
+	{ pinmux(12), 8, 0 },
+	{ pinmux(11), 8, 7 },
+	{ pinmux(11), 8, 6 },
+	{ pinmux(11), 8, 5 },
+	{ pinmux(11), 8, 4 },
+	{ pinmux(11), 8, 3 },
+	{ pinmux(11), 8, 2 },
+	{ pinmux(11), 8, 1 },
+	{ pinmux(11), 8, 0 },
+	{ pinmux(19), 8, 6 },	/* GP6[0] */
+	{ pinmux(19), 8, 5 },
+	{ pinmux(19), 8, 4 },
+	{ pinmux(19), 8, 3 },
+	{ pinmux(19), 8, 2 },
+	{ pinmux(16), 8, 1 },
+	{ pinmux(14), 8, 1 },
+	{ pinmux(14), 8, 0 },
+	{ pinmux(13), 8, 7 },
+	{ pinmux(13), 8, 6 },
+	{ pinmux(13), 8, 5 },
+	{ pinmux(13), 8, 4 },
+	{ pinmux(13), 8, 3 },
+	{ pinmux(13), 8, 2 },
+	{ pinmux(13), 8, 1 },
+	{ pinmux(13), 8, 0 },
+	{ pinmux(18), 8, 1 },	/* GP7[0] */
+	{ pinmux(18), 8, 0 },
+	{ pinmux(17), 8, 7 },
+	{ pinmux(17), 8, 6 },
+	{ pinmux(17), 8, 5 },
+	{ pinmux(17), 8, 4 },
+	{ pinmux(17), 8, 3 },
+	{ pinmux(17), 8, 2 },
+	{ pinmux(17), 8, 1 },
+	{ pinmux(17), 8, 0 },
+	{ pinmux(16), 8, 7 },
+	{ pinmux(16), 8, 6 },
+	{ pinmux(16), 8, 5 },
+	{ pinmux(16), 8, 4 },
+	{ pinmux(16), 8, 3 },
+	{ pinmux(16), 8, 2 },
+	{ pinmux(19), 8, 0 },	/* GP8[0] */
+	{ pinmux(3), 4, 7 },
+	{ pinmux(3), 4, 6 },
+	{ pinmux(3), 4, 5 },
+	{ pinmux(3), 4, 4 },
+	{ pinmux(3), 4, 3 },
+	{ pinmux(3), 4, 2 },
+	{ pinmux(2), 4, 7 },
+	{ pinmux(19), 8, 1 },
+	{ pinmux(19), 8, 0 },
+	{ pinmux(18), 8, 7 },
+	{ pinmux(18), 8, 6 },
+	{ pinmux(18), 8, 5 },
+	{ pinmux(18), 8, 4 },
+	{ pinmux(18), 8, 3 },
+	{ pinmux(18), 8, 2 },
+};
+
+
+
+int gpio_request(int gp, const char *label)
+{
+	if (gp >= MAX_NUM_GPIOS)
+		return -1;
+
+	if (gpio_registry[gp].is_registered)
+		return -1;
+
+	gpio_registry[gp].is_registered = 1;
+	strncpy(gpio_registry[gp].name, label, GPIO_NAME_SIZE);
+	gpio_registry[gp].name[GPIO_NAME_SIZE - 1] = 0;
+
+	davinci_configure_pin_mux(&gpio_pinmux[gp], 1);
+
+	return 0;
+}
+
+
+void gpio_free(int gp)
+{
+	gpio_registry[gp].is_registered = 0;
+}
+
+
+void gpio_toggle_value(int gp)
+{
+	struct davinci_gpio *bank;
+
+	bank = GPIO_BANK(gp);
+	gpio_set_value(gp, !gpio_get_value(gp));
+}
+
+
+int gpio_direction_input(int gp)
+{
+	struct davinci_gpio *bank;
+
+	bank = GPIO_BANK(gp);
+	setbits_le32(&bank->dir, 1U << GPIO_BIT(gp));
+	return 0;
+}
+
+
+int gpio_direction_output(int gp, int value)
+{
+	struct davinci_gpio *bank;
+
+	bank = GPIO_BANK(gp);
+	clrbits_le32(&bank->dir, 1U << GPIO_BIT(gp));
+	gpio_set_value(gp, value);
+	return 0;
+}
+
+
+int gpio_get_value(int gp)
+{
+	struct davinci_gpio *bank;
+	unsigned int ip;
+
+	bank = GPIO_BANK(gp);
+	ip = in_le32(&bank->in_data) & (1U << GPIO_BIT(gp));
+	return ip ? 1 : 0;
+}
+
+
+void gpio_set_value(int gp, int value)
+{
+	struct davinci_gpio *bank;
+
+	bank = GPIO_BANK(gp);
+
+	if (value)
+		bank->set_data = 1U << GPIO_BIT(gp);
+	else
+		bank->clr_data = 1U << GPIO_BIT(gp);
+}
+
+
+void gpio_info(void)
+{
+	int gp, dir, val;
+	struct davinci_gpio *bank;
+
+	for (gp = 0; gp < MAX_NUM_GPIOS; ++gp) {
+		bank = GPIO_BANK(gp);
+		dir = in_le32(&bank->dir) & (1U << GPIO_BIT(gp));
+		val = gpio_get_value(gp);
+
+		printf("% 4d: %s: %d [%c] %s\n",
+			gp, dir ? " in" : "out", val,
+			gpio_registry[gp].is_registered ? 'x' : ' ',
+			gpio_registry[gp].name);
+	}
+}