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+/* SPDX-License-Identifier: GPL-2.0+ */
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+/*
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+ * Simple GPIO access from SPL. This only supports a single GPIO space,
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+ * typically the SoC GPIO banks.
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+ *
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+ * Copyright 2018 Google LLC
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+ */
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+
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+#ifndef __SPL_GPIO_H
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+#define __SPL_GPIO_H
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+
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+#include <asm/gpio.h>
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+
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+/*
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+ * The functions listed here should be implemented in the SoC GPIO driver.
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+ * They correspond to the normal GPIO API (asm-generic/gpio.h). The GPIO
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+ * number is encoded in an unsigned int by an SoC-specific means. Pull
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+ * values are also SoC-specific.
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+ *
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+ * This API should only be used in TPL/SPL where GPIO access is needed but
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+ * driver model is not available (yet) or adds too much overhead.
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+ *
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+ * The caller must supply the GPIO register base since this information is
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+ * often specific to a particular SoC generation. This allows the GPIO
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+ * code to be fairly generic.
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+ *
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+ * Only a single implementation of each of these functions can be provided.
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+ *
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+ * The 'gpio' value can include both a bank and a GPIO number, if desired. The
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+ * encoding is SoC-specific.
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+ */
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+
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+/**
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+ * spl_gpio_set_pull() - Set the pull up/down state of a GPIO
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+ *
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+ * @regs: Pointer to GPIO registers
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+ * @gpio: GPIO to adjust (SoC-specific)
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+ * @pull: Pull value (SoC-specific)
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+ * @return return 0 if OK, -ve on error
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+ */
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+int spl_gpio_set_pull(void *regs, uint gpio, int pull);
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+
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+/**
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+ * spl_gpio_output() - Set a GPIO as an output
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+ *
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+ * @regs: Pointer to GPIO registers
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+ * @gpio: GPIO to adjust (SoC-specific)
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+ * @value: 0 to set the output low, 1 to set it high
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+ * @return return 0 if OK, -ve on error
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+ */
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+int spl_gpio_output(void *regs, uint gpio, int value);
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+
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+/**
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+ * spl_gpio_input() - Set a GPIO as an input
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+ *
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+ * @regs: Pointer to GPIO registers
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+ * @gpio: GPIO to adjust (SoC-specific)
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+ * @return return 0 if OK, -ve on error
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+ */
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+int spl_gpio_input(void *regs, uint gpio);
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+
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+#endif /* __SPL_GPIO_H */
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