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![Axel Lin](/assets/img/avatar_default.png)
In current gpio_set_value() implementation, it always sets the gpio control bit no matter the value argument is 0 or 1. Thus the GPIOs never set to low. This patch fixes this bug. The address bus is used as a mask on read/write operations, so that independent software drivers can set their GPIO bits without affecting any other pins in a single write operation. Thus we don't need a read-modify-write to update the register. Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Stefan Roese <sr@denx.de> Reviewed-by: Vipin Kumar <vipin.kumar@st.com> Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
90 lines
1.5 KiB
C
90 lines
1.5 KiB
C
/*
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* Copyright (C) 2012 Stefan Roese <sr@denx.de>
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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/*
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* Driver for SPEAr600 GPIO controller
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*/
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#include <common.h>
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#include <asm/arch/hardware.h>
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#include <asm/gpio.h>
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#include <asm/io.h>
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#include <errno.h>
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static int gpio_direction(unsigned gpio,
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enum gpio_direction direction)
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{
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struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
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u32 val;
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val = readl(®s->gpiodir);
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if (direction == GPIO_DIRECTION_OUT)
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val |= 1 << gpio;
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else
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val &= ~(1 << gpio);
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writel(val, ®s->gpiodir);
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return 0;
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}
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int gpio_set_value(unsigned gpio, int value)
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{
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struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
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if (value)
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writel(1 << gpio, ®s->gpiodata[DATA_REG_ADDR(gpio)]);
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else
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writel(0, ®s->gpiodata[DATA_REG_ADDR(gpio)]);
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return 0;
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}
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int gpio_get_value(unsigned gpio)
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{
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struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
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u32 val;
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val = readl(®s->gpiodata[DATA_REG_ADDR(gpio)]);
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return !!val;
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}
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int gpio_request(unsigned gpio, const char *label)
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{
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if (gpio >= SPEAR_GPIO_COUNT)
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return -EINVAL;
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return 0;
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}
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int gpio_free(unsigned gpio)
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{
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return 0;
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}
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void gpio_toggle_value(unsigned gpio)
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{
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gpio_set_value(gpio, !gpio_get_value(gpio));
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}
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int gpio_direction_input(unsigned gpio)
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{
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return gpio_direction(gpio, GPIO_DIRECTION_IN);
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}
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int gpio_direction_output(unsigned gpio, int value)
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{
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int ret = gpio_direction(gpio, GPIO_DIRECTION_OUT);
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if (ret < 0)
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return ret;
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gpio_set_value(gpio, value);
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return 0;
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}
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