This provides a way of simulating GPIOs by setting values which are seen by the normal gpio_get/set_value() calls.
Signed-off-by: Simon Glass <s...@chromium.org> --- Changes in v2: - Use generic GPIO command and interface - Fix gpio_direction_output() to actually set the value arch/sandbox/include/asm/gpio.h | 61 ++++++++++++++++ drivers/gpio/Makefile | 1 + drivers/gpio/sandbox.c | 152 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 214 insertions(+), 0 deletions(-) create mode 100644 arch/sandbox/include/asm/gpio.h create mode 100644 drivers/gpio/sandbox.c diff --git a/arch/sandbox/include/asm/gpio.h b/arch/sandbox/include/asm/gpio.h new file mode 100644 index 0000000..405d875 --- /dev/null +++ b/arch/sandbox/include/asm/gpio.h @@ -0,0 +1,61 @@ +/* + * This is the interface to the sandbox GPIO driver for test code which + * wants to change the GPIO values reported to U-Boot. + * + * Copyright (c) 2011 The Chromium OS Authors. + * See file CREDITS for list of people who contributed to this + * project. + * + * 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 + */ + +#ifndef __ASM_SANDBOX_GPIO_H +#define __ASM_SANDBOX_GPIO_H + +/* We use the generic interface, and add a back channel */ +#include <asm-generic/gpio.h> + +/** + * Return the value of a GPIO + * + * @param gp GPIO number + * @return -1 on error, 0 if GPIO is low, >0 if high + */ +int sandbox_gpio_get_value(int gp); + +/** + * @param gp GPIO number + * @param value value to set (0 for low, non-zero for high) + * @return -1 on error, 0 if ok + */ +int sandbox_gpio_set_value(int gp, int value); + +/** + * Return the direction of a GPIO + * + * @param gp GPIO number + * @return -1 on error, 0 if GPIO is input, >0 if output + */ +int sandbox_gpio_get_direction(int gp); + +/** + * @param gp GPIO number + * @param output 0 to set as input, 1 to set as output + * @return -1 on error, 0 if ok + */ +int sandbox_gpio_set_direction(int gp, int output); + +#endif diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index e22c096..7315cfc 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -34,6 +34,7 @@ COBJS-$(CONFIG_MXS_GPIO) += mxs_gpio.o COBJS-$(CONFIG_PCA953X) += pca953x.o COBJS-$(CONFIG_PCA9698) += pca9698.o COBJS-$(CONFIG_S5P) += s5p_gpio.o +COBJS-$(CONFIG_SANDBOX_GPIO) += sandbox.o COBJS-$(CONFIG_TEGRA2_GPIO) += tegra2_gpio.o COBJS-$(CONFIG_DA8XX_GPIO) += da8xx_gpio.o COBJS-$(CONFIG_ALTERA_PIO) += altera_pio.o diff --git a/drivers/gpio/sandbox.c b/drivers/gpio/sandbox.c new file mode 100644 index 0000000..2c36b89 --- /dev/null +++ b/drivers/gpio/sandbox.c @@ -0,0 +1,152 @@ +/* + * Copyright (c) 2011 The Chromium OS Authors. + * See file CREDITS for list of people who contributed to this + * project. + * + * 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/bitops.h> +#include <asm-generic/gpio.h> +#include <asm/gpio.h> + +enum { + CMD_INFO, + CMD_PORT, + CMD_OUTPUT, + CMD_INPUT, +}; + +/* Flags for each GPIO */ +enum { + GPIOF_OUTPUT = 1 << 1, + GPIOF_HIGH = 1 << 2, +}; + +/* TODO: Put this into sandbox state */ +static u8 state[CONFIG_SANDBOX_GPIO_COUNT]; /* State of GPIOs */ + + +/* Access routines for GPIO state */ +static u8 *get_gpio(int gp) +{ + assert(gp >= 0 && gp < CONFIG_SANDBOX_GPIO_COUNT); + return &state[gp]; +} + +static int get_gpio_flag(int gp, int flag) +{ + return *get_gpio(gp) & flag; +} + +static void set_gpio_flag(int gp, int flag, int value) +{ + u8 *gpio = get_gpio(gp); + + if (value) + *gpio |= flag; + else + *gpio &= ~flag; +} + +int sandbox_gpio_get_value(int gp) +{ + if (get_gpio_flag(gp, GPIOF_OUTPUT)) + printf("sandbox_gpio: get_value on output GPIO %d\n", gp); + return *get_gpio(gp) & GPIOF_HIGH; +} + +int sandbox_gpio_set_value(int gp, int value) +{ + set_gpio_flag(gp, GPIOF_HIGH, value); + return 0; +} + +int sandbox_gpio_get_direction(int gp) +{ + return get_gpio_flag(gp, GPIOF_OUTPUT); +} + +int sandbox_gpio_set_direction(int gp, int output) +{ + set_gpio_flag(gp, GPIOF_OUTPUT, output); + return 0; +} + + +/* These functions implement the public interface within U-Boot */ + +/* set GPIO port 'gp' as an input */ +int gpio_direction_input(int gp) +{ + debug("gpio_direction_input: gp = %d\n", gp); + set_gpio_flag(gp, GPIOF_OUTPUT, 0); + return 0; +} + +/* set GPIO port 'gp' as an output, with polarity 'value' */ +int gpio_direction_output(int gp, int value) +{ + debug("gpio_direction_output: gp = %d, value = %d\n", + gp, value); + set_gpio_flag(gp, GPIOF_OUTPUT, 1); + set_gpio_flag(gp, GPIOF_HIGH, value); + return 0; +} + +/* read GPIO IN value of port 'gp' */ +int gpio_get_value(int gp) +{ + debug("gpio_get_value: gp = %d\n", gp); + if (get_gpio_flag(gp, GPIOF_OUTPUT)) + printf("sandbox_gpio: get_value on output GPIO %d\n", gp); + return *get_gpio(gp) & GPIOF_HIGH; +} + +/* write GPIO OUT value to port 'gp' */ +int gpio_set_value(int gp, int value) +{ + debug("gpio_set_value: gp = %d, value = %d\n", gp, value); + if (get_gpio_flag(gp, GPIOF_OUTPUT)) { + set_gpio_flag(gp, GPIOF_HIGH, value); + } else { + printf("sandbox_gpio: set_value on input GPIO %d\n", gp); + return -1; + } + + return 0; +} + +int gpio_request(unsigned gpio, const char *label) +{ + /* for now, do nothing */ + return 0; +} + +int gpio_free(unsigned gpio) +{ + /* for now, do nothing */ + return 0; +} + +/* Display GPIO information */ +int gpio_info(int gp) +{ + printf("Sandbox GPIOs\n"); + return 0; +} -- 1.7.3.1 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot