include/linux/gpio/regmap.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #ifndef _LINUX_GPIO_REGMAP_H
   4 #define _LINUX_GPIO_REGMAP_H
   5
   6 struct device;
   7 struct fwnode_handle;
   8 struct gpio_regmap;
   9 struct irq_domain;
  10 struct regmap;
  11
  12 #define GPIO_REGMAP_ADDR_ZERO ((unsigned int)(-1))
  13 #define GPIO_REGMAP_ADDR(addr) ((addr) ? : GPIO_REGMAP_ADDR_ZERO)
  14
  15 /**
  16  * struct gpio_regmap_config - Description of a generic regmap gpio_chip.
  17  * @parent:             The parent device
  18  * @regmap:             The regmap used to access the registers
  19  *                      given, the name of the device is used
  20  * @fwnode:             (Optional) The firmware node.
  21  *                      If not given, the fwnode of the parent is used.
  22  * @label:              (Optional) Descriptive name for GPIO controller.
  23  *                      If not given, the name of the device is used.
  24  * @ngpio:              Number of GPIOs
  25  * @names:              (Optional) Array of names for gpios
  26  * @reg_dat_base:       (Optional) (in) register base address
  27  * @reg_set_base:       (Optional) set register base address
  28  * @reg_clr_base:       (Optional) clear register base address
  29  * @reg_dir_in_base:    (Optional) in setting register base address
  30  * @reg_dir_out_base:   (Optional) out setting register base address
  31  * @reg_stride:         (Optional) May be set if the registers (of the
  32  *                      same type, dat, set, etc) are not consecutive.
  33  * @ngpio_per_reg:      Number of GPIOs per register
  34  * @irq_domain:         (Optional) IRQ domain if the controller is
  35  *                      interrupt-capable
  36  * @reg_mask_xlate:     (Optional) Translates base address and GPIO
  37  *                      offset to a register/bitmask pair. If not
  38  *                      given the default gpio_regmap_simple_xlate()
  39  *                      is used.
  40  * @drvdata:            (Optional) Pointer to driver specific data which is
  41  *                      not used by gpio-remap but is provided "as is" to the
  42  *                      driver callback(s).
  43  *
  44  * The ->reg_mask_xlate translates a given base address and GPIO offset to
  45  * register and mask pair. The base address is one of the given register
  46  * base addresses in this structure.
  47  *
  48  * Although all register base addresses are marked as optional, there are
  49  * several rules:
  50  *     1. if you only have @reg_dat_base set, then it is input-only
  51  *     2. if you only have @reg_set_base set, then it is output-only
  52  *     3. if you have either @reg_dir_in_base or @reg_dir_out_base set, then
  53  *        you have to set both @reg_dat_base and @reg_set_base
  54  *     4. if you have @reg_set_base set, you may also set @reg_clr_base to have
  55  *        two different registers for setting and clearing the output. This is
  56  *        also valid for the output-only case.
  57  *     5. @reg_dir_in_base and @reg_dir_out_base are exclusive; is there really
  58  *        hardware which has redundant registers?
  59  *
  60  * Note: All base addresses may have the special value %GPIO_REGMAP_ADDR_ZERO
  61  * which forces the address to the value 0.
  62  */
  63 struct gpio_regmap_config {
  64         struct device *parent;
  65         struct regmap *regmap;
  66         struct fwnode_handle *fwnode;
  67
  68         const char *label;
  69         int ngpio;
  70         const char *const *names;
  71
  72         unsigned int reg_dat_base;
  73         unsigned int reg_set_base;
  74         unsigned int reg_clr_base;
  75         unsigned int reg_dir_in_base;
  76         unsigned int reg_dir_out_base;
  77         int reg_stride;
  78         int ngpio_per_reg;
  79         struct irq_domain *irq_domain;
  80
  81         int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
  82                               unsigned int offset, unsigned int *reg,
  83                               unsigned int *mask);
  84
  85         void *drvdata;
  86 };
  87
  88 struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config);
  89 void gpio_regmap_unregister(struct gpio_regmap *gpio);
  90 struct gpio_regmap *devm_gpio_regmap_register(struct device *dev,
  91                                               const struct gpio_regmap_config *config);
  92 void *gpio_regmap_get_drvdata(struct gpio_regmap *gpio);
  93
  94 #endif /* _LINUX_GPIO_REGMAP_H */