linux/gpio/regmap.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002
0003 #ifndef _LINUX_GPIO_REGMAP_H
0004 #define _LINUX_GPIO_REGMAP_H
0005
0006 struct device;
0007 struct fwnode_handle;
0008 struct gpio_regmap;
0009 struct irq_domain;
0010 struct regmap;
0011
0012 #define GPIO_REGMAP_ADDR_ZERO ((unsigned int)(-1))
0013 #define GPIO_REGMAP_ADDR(addr) ((addr) ? : GPIO_REGMAP_ADDR_ZERO)
0014
0015 /**
0016  * struct gpio_regmap_config - Description of a generic regmap gpio_chip.
0017  * @parent:     The parent device
0018  * @regmap:     The regmap used to access the registers
0019  *          given, the name of the device is used
0020  * @fwnode:     (Optional) The firmware node.
0021  *          If not given, the fwnode of the parent is used.
0022  * @label:      (Optional) Descriptive name for GPIO controller.
0023  *          If not given, the name of the device is used.
0024  * @ngpio:      Number of GPIOs
0025  * @names:      (Optional) Array of names for gpios
0026  * @reg_dat_base:   (Optional) (in) register base address
0027  * @reg_set_base:   (Optional) set register base address
0028  * @reg_clr_base:   (Optional) clear register base address
0029  * @reg_dir_in_base:    (Optional) in setting register base address
0030  * @reg_dir_out_base:   (Optional) out setting register base address
0031  * @reg_stride:     (Optional) May be set if the registers (of the
0032  *          same type, dat, set, etc) are not consecutive.
0033  * @ngpio_per_reg:  Number of GPIOs per register
0034  * @irq_domain:     (Optional) IRQ domain if the controller is
0035  *          interrupt-capable
0036  * @reg_mask_xlate:     (Optional) Translates base address and GPIO
0037  *          offset to a register/bitmask pair. If not
0038  *          given the default gpio_regmap_simple_xlate()
0039  *          is used.
0040  * @drvdata:        (Optional) Pointer to driver specific data which is
0041  *          not used by gpio-remap but is provided "as is" to the
0042  *          driver callback(s).
0043  *
0044  * The ->reg_mask_xlate translates a given base address and GPIO offset to
0045  * register and mask pair. The base address is one of the given register
0046  * base addresses in this structure.
0047  *
0048  * Although all register base addresses are marked as optional, there are
0049  * several rules:
0050  *     1. if you only have @reg_dat_base set, then it is input-only
0051  *     2. if you only have @reg_set_base set, then it is output-only
0052  *     3. if you have either @reg_dir_in_base or @reg_dir_out_base set, then
0053  *        you have to set both @reg_dat_base and @reg_set_base
0054  *     4. if you have @reg_set_base set, you may also set @reg_clr_base to have
0055  *        two different registers for setting and clearing the output. This is
0056  *        also valid for the output-only case.
0057  *     5. @reg_dir_in_base and @reg_dir_out_base are exclusive; is there really
0058  *        hardware which has redundant registers?
0059  *
0060  * Note: All base addresses may have the special value %GPIO_REGMAP_ADDR_ZERO
0061  * which forces the address to the value 0.
0062  */
0063 struct gpio_regmap_config {
0064     struct device *parent;
0065     struct regmap *regmap;
0066     struct fwnode_handle *fwnode;
0067
0068     const char *label;
0069     int ngpio;
0070     const char *const *names;
0071
0072     unsigned int reg_dat_base;
0073     unsigned int reg_set_base;
0074     unsigned int reg_clr_base;
0075     unsigned int reg_dir_in_base;
0076     unsigned int reg_dir_out_base;
0077     int reg_stride;
0078     int ngpio_per_reg;
0079     struct irq_domain *irq_domain;
0080
0081     int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
0082                   unsigned int offset, unsigned int *reg,
0083                   unsigned int *mask);
0084
0085     void *drvdata;
0086 };
0087
0088 struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config);
0089 void gpio_regmap_unregister(struct gpio_regmap *gpio);
0090 struct gpio_regmap *devm_gpio_regmap_register(struct device *dev,
0091                           const struct gpio_regmap_config *config);
0092 void *gpio_regmap_get_drvdata(struct gpio_regmap *gpio);
0093
0094 #endif /* _LINUX_GPIO_REGMAP_H */