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linux/drivers/gpio/gpio-i8255.h

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gpio: i8255: Introduce the Intel 8255 interface library module Exposes consumer library functions providing support for interfaces compatible with the venerable Intel 8255 Programmable Peripheral Interface (PPI). The Intel 8255 PPI first appeared in the early 1970s, initially for the Intel 8080 and later appearing in the original IBM-PC. The popularity of the original Intel 8255 chip led to many subsequent variants and clones of the interface in various chips and integrated circuits. Although still popular, interfaces compatible with the Intel 8255 PPI are nowdays typically found embedded in larger VLSI processing chips and FPGA components rather than as discrete ICs. A CONFIG_GPIO_I8255 Kconfig option is introduced by this patch. Modules wanting access to these i8255 library functions should select this Kconfig option, and import the I8255 symbol namespace. Tested-by: Fred Eckert <Frede@cmslaser.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Cc: John Hentges <jhentges@accesio.com> Cc: Jay Dolan <jay.dolan@accesio.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-07-20 06:45:59 -07:00
/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright 2022 William Breathitt Gray */
#ifndef _I8255_H_
#define _I8255_H_
gpio: i8255: Migrate to gpio-regmap API The regmap API supports IO port accessors so we can take advantage of regmap abstractions rather than handling access to the device registers directly in the driver. By leveraging the gpio-regmap API, the i8255 library is reduced to simply a devm_i8255_regmap_register() function, a configuration structure struct i8255_regmap_config, and a helper macro i8255_volatile_regmap_range() provided to simplify volatile PPI register hinting for the regmap. Legacy functions and code will be removed once all consumers have migrated to the new i8255 library interface. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2022-12-27 07:09:43 -07:00
struct device;
struct irq_domain;
struct regmap;
#define i8255_volatile_regmap_range(_base) regmap_reg_range(_base, _base + 0x2)
/**
* struct i8255_regmap_config - Configuration for the register map of an i8255
* @parent: parent device
* @map: regmap for the i8255
* @num_ppi: number of i8255 Programmable Peripheral Interface
* @names: (optional) array of names for gpios
* @domain: (optional) IRQ domain if the controller is interrupt-capable
*
* Note: The regmap is expected to have cache enabled and i8255 control
* registers not marked as volatile.
*/
struct i8255_regmap_config {
struct device *parent;
struct regmap *map;
int num_ppi;
const char *const *names;
struct irq_domain *domain;
};
int devm_i8255_regmap_register(struct device *dev,
const struct i8255_regmap_config *config);
gpio: i8255: Introduce the Intel 8255 interface library module Exposes consumer library functions providing support for interfaces compatible with the venerable Intel 8255 Programmable Peripheral Interface (PPI). The Intel 8255 PPI first appeared in the early 1970s, initially for the Intel 8080 and later appearing in the original IBM-PC. The popularity of the original Intel 8255 chip led to many subsequent variants and clones of the interface in various chips and integrated circuits. Although still popular, interfaces compatible with the Intel 8255 PPI are nowdays typically found embedded in larger VLSI processing chips and FPGA components rather than as discrete ICs. A CONFIG_GPIO_I8255 Kconfig option is introduced by this patch. Modules wanting access to these i8255 library functions should select this Kconfig option, and import the I8255 symbol namespace. Tested-by: Fred Eckert <Frede@cmslaser.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Cc: John Hentges <jhentges@accesio.com> Cc: Jay Dolan <jay.dolan@accesio.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-07-20 06:45:59 -07:00
#endif /* _I8255_H_ */
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