X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=include%2Fasm-generic%2Fgpio.h;h=3b96b8209a10b09d2cdcdf1f559c5fa2787831d7;hb=9ec84f103b3f3e770043b06042e5d2d6f2339e39;hp=bfedbe44596aa31fb2266f7e052a63401f06d181;hpb=caddc17f3019a437b972cd04a8c9a9cbea344def;p=u-boot

diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index bfedbe4459..3b96b8209a 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -1,23 +1,7 @@
 /*
  * Copyright (c) 2011 The Chromium OS Authors.
  * Copyright (c) 2011, NVIDIA Corp. All rights reserved.
- * 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
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #ifndef _ASM_GENERIC_GPIO_H_
@@ -26,6 +10,15 @@
 /*
  * Generic GPIO API for U-Boot
  *
+ * --
+ * NB: This is deprecated. Please use the driver model functions instead:
+ *
+ *    - gpio_request_by_name()
+ *    - dm_gpio_get_value() etc.
+ *
+ * For now we need a dm_ prefix on some functions to avoid name collision.
+ * --
+ *
  * GPIOs are numbered from 0 to GPIO_COUNT-1 which value is defined
  * by the SOC/architecture.
  *
@@ -42,8 +35,12 @@
  */
 
 /**
- * Request a gpio. This should be called before any of the other functions
- * are used on this gpio.
+ * @deprecated	Please use driver model instead
+ * Request a GPIO. This should be called before any of the other functions
+ * are used on this GPIO.
+ *
+ * Note: With driver model, the label is allocated so there is no need for
+ * the caller to preserve it.
  *
  * @param gp	GPIO number
  * @param label	User label for this GPIO
@@ -52,6 +49,7 @@
 int gpio_request(unsigned gpio, const char *label);
 
 /**
+ * @deprecated	Please use driver model instead
  * Stop using the GPIO.  This function should not alter pin configuration.
  *
  * @param gpio	GPIO number
@@ -60,6 +58,7 @@ int gpio_request(unsigned gpio, const char *label);
 int gpio_free(unsigned gpio);
 
 /**
+ * @deprecated	Please use driver model instead
  * Make a GPIO an input.
  *
  * @param gpio	GPIO number
@@ -68,6 +67,7 @@ int gpio_free(unsigned gpio);
 int gpio_direction_input(unsigned gpio);
 
 /**
+ * @deprecated	Please use driver model instead
  * Make a GPIO an output, and set its value.
  *
  * @param gpio	GPIO number
@@ -77,6 +77,7 @@ int gpio_direction_input(unsigned gpio);
 int gpio_direction_output(unsigned gpio, int value);
 
 /**
+ * @deprecated	Please use driver model instead
  * Get a GPIO's value. This will work whether the GPIO is an input
  * or an output.
  *
@@ -86,6 +87,7 @@ int gpio_direction_output(unsigned gpio, int value);
 int gpio_get_value(unsigned gpio);
 
 /**
+ * @deprecated	Please use driver model instead
  * Set an output GPIO's value. The GPIO must already be an output or
  * this function may have no effect.
  *
@@ -94,4 +96,441 @@ int gpio_get_value(unsigned gpio);
  * @return 0 if ok, -1 on error
  */
 int gpio_set_value(unsigned gpio, int value);
+
+/* State of a GPIO, as reported by get_function() */
+enum gpio_func_t {
+	GPIOF_INPUT = 0,
+	GPIOF_OUTPUT,
+	GPIOF_UNUSED,		/* Not claimed */
+	GPIOF_UNKNOWN,		/* Not known */
+	GPIOF_FUNC,		/* Not used as a GPIO */
+
+	GPIOF_COUNT,
+};
+
+struct udevice;
+
+struct gpio_desc {
+	struct udevice *dev;	/* Device, NULL for invalid GPIO */
+	unsigned long flags;
+#define GPIOD_REQUESTED		(1 << 0)	/* Requested/claimed */
+#define GPIOD_IS_OUT		(1 << 1)	/* GPIO is an output */
+#define GPIOD_IS_IN		(1 << 2)	/* GPIO is an output */
+#define GPIOD_ACTIVE_LOW	(1 << 3)	/* value has active low */
+#define GPIOD_IS_OUT_ACTIVE	(1 << 4)	/* set output active */
+
+	uint offset;		/* GPIO offset within the device */
+	/*
+	 * We could consider adding the GPIO label in here. Possibly we could
+	 * use this structure for internal GPIO information.
+	 */
+};
+
+/**
+ * dm_gpio_is_valid() - Check if a GPIO is gpio_is_valie
+ *
+ * @desc:	GPIO description containing device, offset and flags,
+ *		previously returned by gpio_request_by_name()
+ * @return true if valid, false if not
+ */
+static inline bool dm_gpio_is_valid(struct gpio_desc *desc)
+{
+	return desc->dev != NULL;
+}
+
+/**
+ * gpio_get_status() - get the current GPIO status as a string
+ *
+ * Obtain the current GPIO status as a string which can be presented to the
+ * user. A typical string is:
+ *
+ * "b4:  in: 1 [x] sdmmc_cd"
+ *
+ * which means this is GPIO bank b, offset 4, currently set to input, current
+ * value 1, [x] means that it is requested and the owner is 'sdmmc_cd'
+ *
+ * TODO(sjg@chromium.org): This should use struct gpio_desc
+ *
+ * @dev:	Device to check
+ * @offset:	Offset of device GPIO to check
+ * @buf:	Place to put string
+ * @buffsize:	Size of string including \0
+ */
+int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize);
+
+/**
+ * gpio_get_function() - get the current function for a GPIO pin
+ *
+ * Note this returns GPIOF_UNUSED if the GPIO is not requested.
+ *
+ * TODO(sjg@chromium.org): This should use struct gpio_desc
+ *
+ * @dev:	Device to check
+ * @offset:	Offset of device GPIO to check
+ * @namep:	If non-NULL, this is set to the nane given when the GPIO
+ *		was requested, or -1 if it has not been requested
+ * @return  -ENODATA if the driver returned an unknown function,
+ * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
+ * GPIOF_UNUSED if the GPIO has not been requested. Otherwise returns the
+ * function from enum gpio_func_t.
+ */
+int gpio_get_function(struct udevice *dev, int offset, const char **namep);
+
+/**
+ * gpio_get_raw_function() - get the current raw function for a GPIO pin
+ *
+ * Note this does not return GPIOF_UNUSED - it will always return the GPIO
+ * driver's view of a pin function, even if it is not correctly set up.
+ *
+ * TODO(sjg@chromium.org): This should use struct gpio_desc
+ *
+ * @dev:	Device to check
+ * @offset:	Offset of device GPIO to check
+ * @namep:	If non-NULL, this is set to the nane given when the GPIO
+ *		was requested, or -1 if it has not been requested
+ * @return  -ENODATA if the driver returned an unknown function,
+ * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
+ * Otherwise returns the function from enum gpio_func_t.
+ */
+int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep);
+
+/**
+ * gpio_requestf() - request a GPIO using a format string for the owner
+ *
+ * This is a helper function for gpio_request(). It allows you to provide
+ * a printf()-format string for the GPIO owner. It calls gpio_request() with
+ * the string that is created
+ */
+int gpio_requestf(unsigned gpio, const char *fmt, ...)
+		__attribute__ ((format (__printf__, 2, 3)));
+
+struct fdtdec_phandle_args;
+
+/**
+ * struct struct dm_gpio_ops - Driver model GPIO operations
+ *
+ * Refer to functions above for description. These function largely copy
+ * the old API.
+ *
+ * This is trying to be close to Linux GPIO API. Once the U-Boot uses the
+ * new DM GPIO API, this should be really easy to flip over to the Linux
+ * GPIO API-alike interface.
+ *
+ * Also it would be useful to standardise additional functions like
+ * pullup, slew rate and drive strength.
+ *
+ * gpio_request)( and gpio_free() are optional - if NULL then they will
+ * not be called.
+ *
+ * Note that @offset is the offset from the base GPIO of the device. So
+ * offset 0 is the device's first GPIO and offset o-1 is the last GPIO,
+ * where o is the number of GPIO lines controlled by the device. A device
+ * is typically used to control a single bank of GPIOs. Within complex
+ * SoCs there may be many banks and therefore many devices all referring
+ * to the different IO addresses within the SoC.
+ *
+ * The uclass combines all GPIO devices together to provide a consistent
+ * numbering from 0 to n-1, where n is the number of GPIOs in total across
+ * all devices. Be careful not to confuse offset with gpio in the parameters.
+ */
+struct dm_gpio_ops {
+	int (*request)(struct udevice *dev, unsigned offset, const char *label);
+	int (*free)(struct udevice *dev, unsigned offset);
+	int (*direction_input)(struct udevice *dev, unsigned offset);
+	int (*direction_output)(struct udevice *dev, unsigned offset,
+				int value);
+	int (*get_value)(struct udevice *dev, unsigned offset);
+	int (*set_value)(struct udevice *dev, unsigned offset, int value);
+	/**
+	 * get_function() Get the GPIO function
+	 *
+	 * @dev:     Device to check
+	 * @offset:  GPIO offset within that device
+	 * @return current function - GPIOF_...
+	 */
+	int (*get_function)(struct udevice *dev, unsigned offset);
+
+	/**
+	 * xlate() - Translate phandle arguments into a GPIO description
+	 *
+	 * This function should set up the fields in desc according to the
+	 * information in the arguments. The uclass will have set up:
+	 *
+	 *   @desc->dev to @dev
+	 *   @desc->flags to 0
+	 *   @desc->offset to the value of the first argument in args, if any,
+	 *		otherwise -1 (which is invalid)
+	 *
+	 * This method is optional so if the above defaults suit it can be
+	 * omitted. Typical behaviour is to set up the GPIOD_ACTIVE_LOW flag
+	 * in desc->flags.
+	 *
+	 * Note that @dev is passed in as a parameter to follow driver model
+	 * uclass conventions, even though it is already available as
+	 * desc->dev.
+	 *
+	 * @dev:	GPIO device
+	 * @desc:	Place to put GPIO description
+	 * @args:	Arguments provided in descripion
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*xlate)(struct udevice *dev, struct gpio_desc *desc,
+		     struct fdtdec_phandle_args *args);
+};
+
+/**
+ * struct gpio_dev_priv - information about a device used by the uclass
+ *
+ * The uclass combines all active GPIO devices into a unified numbering
+ * scheme. To do this it maintains some private information about each
+ * device.
+ *
+ * To implement driver model support in your GPIO driver, add a probe
+ * handler, and set @gpio_count and @bank_name correctly in that handler.
+ * This tells the uclass the name of the GPIO bank and the number of GPIOs
+ * it contains.
+ *
+ * @bank_name: Name of the GPIO device (e.g 'a' means GPIOs will be called
+ * 'A0', 'A1', etc.
+ * @gpio_count: Number of GPIOs in this device
+ * @gpio_base: Base GPIO number for this device. For the first active device
+ * this will be 0; the numbering for others will follow sequentially so that
+ * @gpio_base for device 1 will equal the number of GPIOs in device 0.
+ * @name: Array of pointers to the name for each GPIO in this bank. The
+ * value of the pointer will be NULL if the GPIO has not been claimed.
+ */
+struct gpio_dev_priv {
+	const char *bank_name;
+	unsigned gpio_count;
+	unsigned gpio_base;
+	char **name;
+};
+
+/* Access the GPIO operations for a device */
+#define gpio_get_ops(dev)	((struct dm_gpio_ops *)(dev)->driver->ops)
+
+/**
+ * gpio_get_bank_info - Return information about a GPIO bank/device
+ *
+ * This looks up a device and returns both its GPIO base name and the number
+ * of GPIOs it controls.
+ *
+ * @dev: Device to look up
+ * @offset_count: Returns number of GPIOs within this bank
+ * @return bank name of this device
+ */
+const char *gpio_get_bank_info(struct udevice *dev, int *offset_count);
+
+/**
+ * gpio_lookup_name - Look up a GPIO name and return its details
+ *
+ * This is used to convert a named GPIO into a device, offset and GPIO
+ * number.
+ *
+ * @name: GPIO name to look up
+ * @devp: Returns pointer to device which contains this GPIO
+ * @offsetp: Returns the offset number within this device
+ * @gpiop: Returns the absolute GPIO number, numbered from 0
+ */
+int gpio_lookup_name(const char *name, struct udevice **devp,
+		     unsigned int *offsetp, unsigned int *gpiop);
+
+/**
+ * get_gpios() - Turn the values of a list of GPIOs into an integer
+ *
+ * This puts the value of the first GPIO into bit 0, the second into bit 1,
+ * etc. then returns the resulting integer.
+ *
+ * @gpio_list: List of GPIOs to collect
+ * @return resulting integer value
+ */
+unsigned gpio_get_values_as_int(const int *gpio_list);
+
+/**
+ * gpio_request_by_name() - Locate and request a GPIO by name
+ *
+ * This operates by looking up the given list name in the device (device
+ * tree property) and requesting the GPIO for use. The property must exist
+ * in @dev's node.
+ *
+ * Use @flags to specify whether the GPIO should be an input or output. In
+ * principle this can also come from the device tree binding but most
+ * bindings don't provide this information. Specifically, when the GPIO uclass
+ * calls the xlate() method, it can return default flags, which are then
+ * ORed with this @flags.
+ *
+ * If we find that requesting the GPIO is not always needed we could add a
+ * new function or a new GPIOD_NO_REQUEST flag.
+ *
+ * At present driver model has no reference counting so if one device
+ * requests a GPIO which subsequently is unbound, the @desc->dev pointer
+ * will be invalid. However this will only happen if the GPIO device is
+ * unbound, not if it is removed, so this seems like a reasonable limitation
+ * for now. There is no real use case for unbinding drivers in normal
+ * operation.
+ *
+ * The device tree binding is doc/device-tree-bindings/gpio/gpio.txt in
+ * generate terms and each specific device may add additional details in
+ * a binding file in the same directory.
+ *
+ * @dev:	Device requesting the GPIO
+ * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
+ * @index:	Index number of the GPIO in that list use request (0=first)
+ * @desc:	Returns GPIO description information. If there is no such
+ *		GPIO, dev->dev will be NULL.
+ * @flags:	Indicates the GPIO input/output settings (GPIOD_...)
+ * @return 0 if OK, -ENOENT if the GPIO does not exist, -EINVAL if there is
+ * something wrong with the list, or other -ve for another error (e.g.
+ * -EBUSY if a GPIO was already requested)
+ */
+int gpio_request_by_name(struct udevice *dev, const char *list_name,
+			 int index, struct gpio_desc *desc, int flags);
+
+/**
+ * gpio_request_list_by_name() - Request a list of GPIOs
+ *
+ * Reads all the GPIOs from a list and requetss them. See
+ * gpio_request_by_name() for additional details. Lists should not be
+ * misused to hold unrelated or optional GPIOs. They should only be used
+ * for things like parallel data lines. A zero phandle terminates the list
+ * the list.
+ *
+ * This function will either succeed, and request all GPIOs in the list, or
+ * fail and request none (it will free already-requested GPIOs in case of
+ * an error part-way through).
+ *
+ * @dev:	Device requesting the GPIO
+ * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
+ * @desc_list:	Returns a list of GPIO description information
+ * @max_count:	Maximum number of GPIOs to return (@desc_list must be at least
+ *		this big)
+ * @flags:	Indicates the GPIO input/output settings (GPIOD_...)
+ * @return number of GPIOs requested, or -ve on error
+ */
+int gpio_request_list_by_name(struct udevice *dev, const char *list_name,
+			      struct gpio_desc *desc_list, int max_count,
+			      int flags);
+
+/**
+ * gpio_get_list_count() - Returns the number of GPIOs in a list
+ *
+ * Counts the GPIOs in a list. See gpio_request_by_name() for additional
+ * details.
+ *
+ * @dev:	Device requesting the GPIO
+ * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
+ * @return number of GPIOs (0 for an empty property) or -ENOENT if the list
+ * does not exist
+ */
+int gpio_get_list_count(struct udevice *dev, const char *list_name);
+
+/**
+ * gpio_request_by_name_nodev() - request GPIOs without a device
+ *
+ * This is a version of gpio_request_list_by_name() that does not use a
+ * device. Avoid it unless the caller is not yet using driver model
+ */
+int gpio_request_by_name_nodev(const void *blob, int node,
+			       const char *list_name,
+			       int index, struct gpio_desc *desc, int flags);
+
+/**
+ * gpio_request_list_by_name_nodev() - request GPIOs without a device
+ *
+ * This is a version of gpio_request_list_by_name() that does not use a
+ * device. Avoid it unless the caller is not yet using driver model
+ */
+int gpio_request_list_by_name_nodev(const void *blob, int node,
+				    const char *list_name,
+				    struct gpio_desc *desc_list, int max_count,
+				    int flags);
+
+/**
+ * dm_gpio_free() - Free a single GPIO
+ *
+ * This frees a single GPIOs previously returned from gpio_request_by_name().
+ *
+ * @dev:	Device which requested the GPIO
+ * @desc:	GPIO to free
+ * @return 0 if OK, -ve on error
+ */
+int dm_gpio_free(struct udevice *dev, struct gpio_desc *desc);
+
+/**
+ * gpio_free_list() - Free a list of GPIOs
+ *
+ * This frees a list of GPIOs previously returned from
+ * gpio_request_list_by_name().
+ *
+ * @dev:	Device which requested the GPIOs
+ * @desc:	List of GPIOs to free
+ * @count:	Number of GPIOs in the list
+ * @return 0 if OK, -ve on error
+ */
+int gpio_free_list(struct udevice *dev, struct gpio_desc *desc, int count);
+
+/**
+ * gpio_free_list_nodev() - free GPIOs without a device
+ *
+ * This is a version of gpio_free_list() that does not use a
+ * device. Avoid it unless the caller is not yet using driver model
+ */
+int gpio_free_list_nodev(struct gpio_desc *desc, int count);
+
+/**
+ * dm_gpio_get_value() - Get the value of a GPIO
+ *
+ * This is the driver model version of the existing gpio_get_value() function
+ * and should be used instead of that.
+ *
+ * For now, these functions have a dm_ prefix since they conflict with
+ * existing names.
+ *
+ * @desc:	GPIO description containing device, offset and flags,
+ *		previously returned by gpio_request_by_name()
+ * @return GPIO value (0 for inactive, 1 for active) or -ve on error
+ */
+int dm_gpio_get_value(struct gpio_desc *desc);
+
+int dm_gpio_set_value(struct gpio_desc *desc, int value);
+
+/**
+ * dm_gpio_set_dir() - Set the direction for a GPIO
+ *
+ * This sets up the direction according tot the provided flags. It will do
+ * nothing unless the direction is actually specified.
+ *
+ * @desc:	GPIO description containing device, offset and flags,
+ *		previously returned by gpio_request_by_name()
+ * @return 0 if OK, -ve on error
+ */
+int dm_gpio_set_dir(struct gpio_desc *desc);
+
+/**
+ * dm_gpio_set_dir_flags() - Set direction using specific flags
+ *
+ * This is like dm_gpio_set_dir() except that the flags value is provided
+ * instead of being used from desc->flags. This is needed because in many
+ * cases the GPIO description does not include direction information.
+ * Note that desc->flags is updated by this function.
+ *
+ * @desc:	GPIO description containing device, offset and flags,
+ *		previously returned by gpio_request_by_name()
+ * @flags:	New flags to use
+ * @return 0 if OK, -ve on error, in which case desc->flags is not updated
+ */
+int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags);
+
+/**
+ * gpio_get_number() - Get the global GPIO number of a GPIO
+ *
+ * This should only be used for debugging or interest. It returns the nummber
+ * that should be used for gpio_get_value() etc. to access this GPIO.
+ *
+ * @desc:	GPIO description containing device, offset and flags,
+ *		previously returned by gpio_request_by_name()
+ * @return GPIO number, or -ve if not found
+ */
+int gpio_get_number(struct gpio_desc *desc);
+
 #endif	/* _ASM_GENERIC_GPIO_H_ */