[RFC 2/2] sandbox: add gpio support with libftdi1

[Antony Pavlov <antonynpavlov@gmail.com>]

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
---
 arch/sandbox/Kconfig                           |   1 +
 arch/sandbox/Makefile                          |   6 +-
 arch/sandbox/board/board.c                     |   7 ++
 arch/sandbox/mach-sandbox/include/mach/linux.h |  11 ++
 arch/sandbox/os/Makefile                       |   3 +
 arch/sandbox/os/ftdi.c                         | 167 +++++++++++++++++++++++++
 drivers/gpio/Kconfig                           |   4 +
 drivers/gpio/Makefile                          |   1 +
 drivers/gpio/gpio-libftdi1.c                   | 116 +++++++++++++++++
 9 files changed, 315 insertions(+), 1 deletion(-)

diff --git a/arch/sandbox/Kconfig b/arch/sandbox/Kconfig
index 9c72673bd..3f1cefb83 100644
--- a/arch/sandbox/Kconfig
+++ b/arch/sandbox/Kconfig
@@ -1,6 +1,7 @@
 config SANDBOX
 	bool
 	select OFTREE
+	select GPIOLIB
 	default y
 
 config ARCH_TEXT_BASE
diff --git a/arch/sandbox/Makefile b/arch/sandbox/Makefile
index 9d545c3b7..85c70b5e8 100644
--- a/arch/sandbox/Makefile
+++ b/arch/sandbox/Makefile
@@ -41,9 +41,13 @@ ifeq ($(CONFIG_DRIVER_VIDEO_SDL),y)
 SDL_LIBS := $(shell pkg-config sdl --libs)
 endif
 
+ifeq ($(CONFIG_GPIO_LIBFTDI1),y)
+FTDI1_LIBS := $(shell pkg-config libftdi1 --libs)
+endif
+
 cmd_barebox__ = $(CC) -o $@ -Wl,-T,$(barebox-lds) \
 	-Wl,--start-group $(barebox-common) -Wl,--end-group \
-	-lrt -lpthread $(SDL_LIBS)
+	-lrt -lpthread $(SDL_LIBS) $(FTDI1_LIBS)
 
 common-y += $(BOARD) arch/sandbox/os/
 
diff --git a/arch/sandbox/board/board.c b/arch/sandbox/board/board.c
index dcad3c249..5ab47e21c 100644
--- a/arch/sandbox/board/board.c
+++ b/arch/sandbox/board/board.c
@@ -42,6 +42,11 @@ static struct device_d sdl_device = {
 	.platform_data = &mode,
 };
 
+static struct device_d libftdi1_device = {
+	.id	  = DEVICE_ID_DYNAMIC,
+	.name     = "libftdi1-gpio",
+};
+
 static int devices_init(void)
 {
 	platform_device_register(&tap_device);
@@ -54,6 +59,8 @@ static int devices_init(void)
 
 	platform_device_register(&sdl_device);
 
+	platform_device_register(&libftdi1_device);
+
 	return 0;
 }
 
diff --git a/arch/sandbox/mach-sandbox/include/mach/linux.h b/arch/sandbox/mach-sandbox/include/mach/linux.h
index 1f11ed449..e52180ae4 100644
--- a/arch/sandbox/mach-sandbox/include/mach/linux.h
+++ b/arch/sandbox/mach-sandbox/include/mach/linux.h
@@ -38,4 +38,15 @@ void sdl_get_bitfield_rgba(struct fb_bitfield *r, struct fb_bitfield *g,
 			    struct fb_bitfield *b, struct fb_bitfield *a);
 void sdl_setpixel(int x, int y, uint8_t r, uint8_t g, uint8_t b, uint8_t a);
 
+struct ft2232_bitbang;
+struct ft2232_bitbang *barebox_libftdi1_open(void);
+void barebox_libftdi1_gpio_direction(struct ft2232_bitbang *ftbb,
+						unsigned off, unsigned dir);
+int barebox_libftdi1_gpio_get_value(struct ft2232_bitbang *ftbb,
+						unsigned off);
+void barebox_libftdi1_gpio_set_value(struct ft2232_bitbang *ftbb,
+						unsigned off, unsigned val);
+int barebox_libftdi1_update(struct ft2232_bitbang *ftbb);
+void barebox_libftdi1_close(void);
+
 #endif /* __ASM_ARCH_LINUX_H */
diff --git a/arch/sandbox/os/Makefile b/arch/sandbox/os/Makefile
index 537f848e0..75baa34a8 100644
--- a/arch/sandbox/os/Makefile
+++ b/arch/sandbox/os/Makefile
@@ -17,3 +17,6 @@ obj-y = common.o tap.o
 
 CFLAGS_sdl.o = $(shell pkg-config sdl --cflags)
 obj-$(CONFIG_DRIVER_VIDEO_SDL) += sdl.o
+
+CFLAGS_ftdi.o = $(shell pkg-config libftdi1 --cflags)
+obj-$(CONFIG_GPIO_LIBFTDI1) += ftdi.o
diff --git a/arch/sandbox/os/ftdi.c b/arch/sandbox/os/ftdi.c
new file mode 100644
index 000000000..b37903dd5
--- /dev/null
+++ b/arch/sandbox/os/ftdi.c
@@ -0,0 +1,167 @@
+/*
+ * sandbox barebox libftdi1 support
+ *
+ * Copyright (C) 2016, 2017 Antony Pavlov <antonynpavlov@gmail.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.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ftdi.h>
+#include <errno.h>
+#include <mach/linux.h>
+
+#define GPIOF_DIR_OUT	(0 << 0)
+#define GPIOF_DIR_IN	(1 << 0)
+
+#define BIT(nr)			(1UL << (nr))
+
+struct ft2232_bitbang {
+	struct ftdi_context *ftdi;
+	uint8_t odata;
+	uint8_t dir;
+};
+
+static struct ft2232_bitbang ftbb;
+
+static inline int ftdi_flush(struct ftdi_context *ftdi)
+{
+	uint8_t buf[1];
+	int ret;
+
+	buf[0] = SEND_IMMEDIATE;
+
+	ret = ftdi_write_data(ftdi, buf, 1);
+
+	return ret;
+}
+
+static int ftdi_get_high_byte_data(struct ftdi_context *ftdi, uint8_t *data)
+{
+	uint8_t obuf;
+	int ret;
+
+	obuf = GET_BITS_HIGH;
+	ret = ftdi_write_data(ftdi, &obuf, 1);
+
+	ret = ftdi_read_data(ftdi, data, 1);
+
+	return ret;
+}
+
+static int ftdi_set_high_byte_data_dir(struct ft2232_bitbang *ftbb)
+{
+	uint8_t buf[3];
+	int ret;
+
+	buf[0] = SET_BITS_HIGH;
+	buf[1] = ftbb->odata;
+	buf[2] = ftbb->dir;
+
+	ret = ftdi_write_data(ftbb->ftdi, buf, 3);
+	ftdi_flush(ftbb->ftdi);
+
+	return ret;
+}
+
+int barebox_libftdi1_update(struct ft2232_bitbang *ftbb)
+{
+	return ftdi_set_high_byte_data_dir(ftbb);
+}
+
+void barebox_libftdi1_gpio_direction(struct ft2232_bitbang *ftbb,
+					unsigned off, unsigned dir)
+{
+	switch (dir) {
+	case GPIOF_DIR_IN:
+		ftbb->dir &= ~BIT(off);
+		break;
+	case GPIOF_DIR_OUT:
+		ftbb->dir |= BIT(off);
+		break;
+	default:
+		printf("%s:%d: invalid dir argument\n", __FILE__, __LINE__);
+	}
+}
+
+int barebox_libftdi1_gpio_get_value(struct ft2232_bitbang *ftbb, unsigned off)
+{
+	uint8_t data;
+
+	ftdi_get_high_byte_data(ftbb->ftdi, &data);
+
+	return !!(data & BIT(off));
+}
+
+void barebox_libftdi1_gpio_set_value(struct ft2232_bitbang *ftbb,
+					unsigned off, unsigned val)
+{
+	if (val)
+		ftbb->odata |= BIT(off);
+	else
+		ftbb->odata &= ~BIT(off);
+}
+
+int barebox_libftdi1_init(void)
+{
+	struct ftdi_context *ftdi;
+	int ret;
+
+	ftdi = ftdi_new();
+	if (!ftdi) {
+		fprintf(stderr, "ftdi_new failed\n");
+		goto error;
+	}
+
+	ret = ftdi_usb_open(ftdi, 0x0403, 0x6010);
+	if (ret < 0 && ret != -5) {
+		fprintf(stderr, "unable to open ftdi device: %d (%s)\n",
+			ret, ftdi_get_error_string(ftdi));
+		goto error;
+	}
+
+	ftdi_set_interface(ftdi, INTERFACE_A);
+	ftdi_set_bitmode(ftdi, 0x00, BITMODE_MPSSE);
+
+	ftbb.ftdi = ftdi;
+
+	/* reset pins to default neutral state */
+	ftbb.dir = 0;
+	ftbb.odata = 0;
+	ftdi_set_high_byte_data_dir(&ftbb);
+
+	return 0;
+
+error:
+	return -1;
+}
+
+struct ft2232_bitbang *barebox_libftdi1_open(void)
+{
+	if (barebox_libftdi1_init() < 0) {
+		printf("Could not initialize ftdi\n");
+		return NULL;
+	}
+
+	return &ftbb;
+}
+
+void barebox_libftdi1_close(void)
+{
+	struct ftdi_context *ftdi = ftbb.ftdi;
+
+	ftdi_set_interface(ftdi, INTERFACE_ANY);
+	ftdi_usb_close(ftdi);
+	ftdi_free(ftdi);
+}
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 434c5688b..ed93e868a 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -132,6 +132,10 @@ config GPIO_SX150X
 	  Say Y here to build support for the Semtec Sx150x I2C GPIO
 	  expander chip.
 
+config GPIO_LIBFTDI1
+	bool "libftdi1 driver"
+	depends on SANDBOX
+
 endmenu
 
 endif
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index f37dd08f1..f5ed876d5 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_GPIO_CLPS711X)	+= gpio-clps711x.o
 obj-$(CONFIG_GPIO_DIGIC)	+= gpio-digic.o
 obj-$(CONFIG_GPIO_GENERIC)	+= gpio-generic.o
 obj-$(CONFIG_GPIO_IMX)		+= gpio-imx.o
+obj-$(CONFIG_GPIO_LIBFTDI1)	+= gpio-libftdi1.o
 obj-$(CONFIG_GPIO_MXS)		+= gpio-mxs.o
 obj-$(CONFIG_GPIO_JZ4740)	+= gpio-jz4740.o
 obj-$(CONFIG_GPIO_MALTA_FPGA_I2C) += gpio-malta-fpga-i2c.o
diff --git a/drivers/gpio/gpio-libftdi1.c b/drivers/gpio/gpio-libftdi1.c
new file mode 100644
index 000000000..1ceb78029
--- /dev/null
+++ b/drivers/gpio/gpio-libftdi1.c
@@ -0,0 +1,116 @@
+/*
+ * libftdi1 sandbox barebox GPIO driver
+ *
+ * Copyright (C) 2016, 2017 Antony Pavlov <antonynpavlov@gmail.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.
+ *
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <gpio.h>
+#include <init.h>
+#include <malloc.h>
+#include <mach/linux.h>
+
+struct libftdi1_gpio_chip {
+	struct gpio_chip chip;
+	struct ft2232_bitbang *ftbb;
+};
+
+static int libftdi1_gpio_direction_input(struct gpio_chip *chip, unsigned off)
+{
+	struct libftdi1_gpio_chip *gpio =
+		container_of(chip, struct libftdi1_gpio_chip, chip);
+
+	barebox_libftdi1_gpio_direction(gpio->ftbb, off, GPIOF_DIR_IN);
+	barebox_libftdi1_update(gpio->ftbb);
+
+	return 0;
+}
+
+static int libftdi1_gpio_direction_output(
+	struct gpio_chip *chip, unsigned off, int value)
+{
+	struct libftdi1_gpio_chip *gpio =
+		container_of(chip, struct libftdi1_gpio_chip, chip);
+
+	barebox_libftdi1_gpio_set_value(gpio->ftbb, off, value);
+	barebox_libftdi1_gpio_direction(gpio->ftbb, off, GPIOF_DIR_OUT);
+	barebox_libftdi1_update(gpio->ftbb);
+
+	return 0;
+}
+
+static int libftdi1_gpio_get_value(struct gpio_chip *chip, unsigned off)
+{
+	struct libftdi1_gpio_chip *gpio =
+		container_of(chip, struct libftdi1_gpio_chip, chip);
+
+	return barebox_libftdi1_gpio_get_value(gpio->ftbb, off);
+}
+
+static void libftdi1_gpio_set_value(
+	struct gpio_chip *chip, unsigned off, int value)
+{
+	struct libftdi1_gpio_chip *gpio =
+		container_of(chip, struct libftdi1_gpio_chip, chip);
+
+	barebox_libftdi1_gpio_set_value(gpio->ftbb, off, value);
+	barebox_libftdi1_update(gpio->ftbb);
+}
+
+static struct gpio_ops libftdi1_gpio_ops = {
+	.direction_input = libftdi1_gpio_direction_input,
+	.direction_output = libftdi1_gpio_direction_output,
+	.get = libftdi1_gpio_get_value,
+	.set = libftdi1_gpio_set_value,
+};
+
+static int libftdi1_gpio_probe(struct device_d *dev)
+{
+	struct libftdi1_gpio_chip *gpio;
+	struct ft2232_bitbang *ftbb;
+	int ret;
+
+	ftbb = barebox_libftdi1_open();
+	if (!ftbb)
+		return -EIO;
+
+	gpio = xzalloc(sizeof(*gpio));
+
+	gpio->ftbb = ftbb;
+
+	gpio->chip.dev = dev;
+	gpio->chip.ops = &libftdi1_gpio_ops;
+	gpio->chip.base = 0;
+	gpio->chip.ngpio = 8;
+
+	ret = gpiochip_add(&gpio->chip);
+
+	dev_dbg(dev, "%d: probed gpio%d with base %d\n",
+			ret, dev->id, gpio->chip.base);
+
+	return 0;
+}
+
+static void libftdi1_gpio_remove(struct device_d *dev)
+{
+	barebox_libftdi1_close();
+}
+
+static struct driver_d libftdi1_gpio_driver = {
+	.name = "libftdi1-gpio",
+	.probe = libftdi1_gpio_probe,
+	.remove = libftdi1_gpio_remove,
+};
+device_platform_driver(libftdi1_gpio_driver);
-- 
2.11.0


_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox