linux_dsm_epyc7002/include/linux/gpio/driver.h
Linus Walleij d799a4de0a gpio: mmio: Fix up inverted direction registers
The bgpio_init() takes one of two arguments to specify a register
to set the direction of the GPIO line: either dirout that
indicates that a 1 in the bit in that register sets the
corresponding line to output, or dirin which indicates that
a 1 in the bit in that register sets the corresponding line to
input. Conversely setting the bit to 0 on these will turn the
line into input and output respectively. One of these can
be defined but not both.

This means that a platform that sets a bit to 1 for output
only defines dirout and a platform that sets a bit to 0 for
output only defines dirin. In short this defines the polarity
of the direction register.

Both can also be left as NULL meaning the GPIO chip is either
input only or output only.

Tomer Maimon discovered that for get/set chips (those where the
get and set registers are defined but no separate clear register,
and specifying BGPIOF_READ_OUTPUT_REG_SET so that we say we
want to read the output value from the SET register)
we are unconditionally reading the value from the SET register
when the direction bit is 1 and from the DAT register when the
direction bit is 0, not taking the direction bit polarity into
account.

It would be expected that when the direction bit is inverted
(dirin is defined but not dirout) we read the current value from
the DAT register when the bit is 1 and from the SET register
when the bit is 0.

Currently only some versions of ATH79, brcmstb, some versions of
CLP711x, GE, IOP and Loongson use the dirin mode (a 1 in the
register means input). They are unaffected because
BGPIOF_READ_OUTPUT_REG_SET is not set on any of them. (They
do not read back the SET register to figure out the output
value.) So this is no regression with current drivers.

However the behaviour is wrong and does not work with Tomer's
new driver where he needs to use the BGIOF_READ_OUTPUT_REG_SET.
This fixes the above issue by:

- Instead of defining separate functions for the inverted case,
  set up a flag in the gpio_chip that indicates that the
  direction is inverted.
- Remove the special inverted functions for setting
  input/output and getting the direction, rely on the flag
  instead.
- Respect this flag in bgpio_get_set() and
  bgpio_get_set_multiple()

Reported-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10 23:19:17 +02:00

588 lines
18 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_GPIO_DRIVER_H
#define __LINUX_GPIO_DRIVER_H
#include <linux/device.h>
#include <linux/types.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/lockdep.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf-generic.h>
struct gpio_desc;
struct of_phandle_args;
struct device_node;
struct seq_file;
struct gpio_device;
struct module;
#ifdef CONFIG_GPIOLIB
#ifdef CONFIG_GPIOLIB_IRQCHIP
/**
* struct gpio_irq_chip - GPIO interrupt controller
*/
struct gpio_irq_chip {
/**
* @chip:
*
* GPIO IRQ chip implementation, provided by GPIO driver.
*/
struct irq_chip *chip;
/**
* @domain:
*
* Interrupt translation domain; responsible for mapping between GPIO
* hwirq number and Linux IRQ number.
*/
struct irq_domain *domain;
/**
* @domain_ops:
*
* Table of interrupt domain operations for this IRQ chip.
*/
const struct irq_domain_ops *domain_ops;
/**
* @handler:
*
* The IRQ handler to use (often a predefined IRQ core function) for
* GPIO IRQs, provided by GPIO driver.
*/
irq_flow_handler_t handler;
/**
* @default_type:
*
* Default IRQ triggering type applied during GPIO driver
* initialization, provided by GPIO driver.
*/
unsigned int default_type;
/**
* @lock_key:
*
* Per GPIO IRQ chip lockdep classes.
*/
struct lock_class_key *lock_key;
struct lock_class_key *request_key;
/**
* @parent_handler:
*
* The interrupt handler for the GPIO chip's parent interrupts, may be
* NULL if the parent interrupts are nested rather than cascaded.
*/
irq_flow_handler_t parent_handler;
/**
* @parent_handler_data:
*
* Data associated, and passed to, the handler for the parent
* interrupt.
*/
void *parent_handler_data;
/**
* @num_parents:
*
* The number of interrupt parents of a GPIO chip.
*/
unsigned int num_parents;
/**
* @parents:
*
* A list of interrupt parents of a GPIO chip. This is owned by the
* driver, so the core will only reference this list, not modify it.
*/
unsigned int *parents;
/**
* @map:
*
* A list of interrupt parents for each line of a GPIO chip.
*/
unsigned int *map;
/**
* @threaded:
*
* True if set the interrupt handling uses nested threads.
*/
bool threaded;
/**
* @need_valid_mask:
*
* If set core allocates @valid_mask with all bits set to one.
*/
bool need_valid_mask;
/**
* @valid_mask:
*
* If not %NULL holds bitmask of GPIOs which are valid to be included
* in IRQ domain of the chip.
*/
unsigned long *valid_mask;
/**
* @first:
*
* Required for static IRQ allocation. If set, irq_domain_add_simple()
* will allocate and map all IRQs during initialization.
*/
unsigned int first;
};
static inline struct gpio_irq_chip *to_gpio_irq_chip(struct irq_chip *chip)
{
return container_of(chip, struct gpio_irq_chip, chip);
}
#endif
/**
* struct gpio_chip - abstract a GPIO controller
* @label: a functional name for the GPIO device, such as a part
* number or the name of the SoC IP-block implementing it.
* @gpiodev: the internal state holder, opaque struct
* @parent: optional parent device providing the GPIOs
* @owner: helps prevent removal of modules exporting active GPIOs
* @request: optional hook for chip-specific activation, such as
* enabling module power and clock; may sleep
* @free: optional hook for chip-specific deactivation, such as
* disabling module power and clock; may sleep
* @get_direction: returns direction for signal "offset", 0=out, 1=in,
* (same as GPIOF_DIR_XXX), or negative error
* @direction_input: configures signal "offset" as input, or returns error
* @direction_output: configures signal "offset" as output, or returns error
* @get: returns value for signal "offset", 0=low, 1=high, or negative error
* @get_multiple: reads values for multiple signals defined by "mask" and
* stores them in "bits", returns 0 on success or negative error
* @set: assigns output value for signal "offset"
* @set_multiple: assigns output values for multiple signals defined by "mask"
* @set_config: optional hook for all kinds of settings. Uses the same
* packed config format as generic pinconf.
* @to_irq: optional hook supporting non-static gpio_to_irq() mappings;
* implementation may not sleep
* @dbg_show: optional routine to show contents in debugfs; default code
* will be used when this is omitted, but custom code can show extra
* state (such as pullup/pulldown configuration).
* @base: identifies the first GPIO number handled by this chip;
* or, if negative during registration, requests dynamic ID allocation.
* DEPRECATION: providing anything non-negative and nailing the base
* offset of GPIO chips is deprecated. Please pass -1 as base to
* let gpiolib select the chip base in all possible cases. We want to
* get rid of the static GPIO number space in the long run.
* @ngpio: the number of GPIOs handled by this controller; the last GPIO
* handled is (base + ngpio - 1).
* @names: if set, must be an array of strings to use as alternative
* names for the GPIOs in this chip. Any entry in the array
* may be NULL if there is no alias for the GPIO, however the
* array must be @ngpio entries long. A name can include a single printk
* format specifier for an unsigned int. It is substituted by the actual
* number of the gpio.
* @can_sleep: flag must be set iff get()/set() methods sleep, as they
* must while accessing GPIO expander chips over I2C or SPI. This
* implies that if the chip supports IRQs, these IRQs need to be threaded
* as the chip access may sleep when e.g. reading out the IRQ status
* registers.
* @read_reg: reader function for generic GPIO
* @write_reg: writer function for generic GPIO
* @be_bits: if the generic GPIO has big endian bit order (bit 31 is representing
* line 0, bit 30 is line 1 ... bit 0 is line 31) this is set to true by the
* generic GPIO core. It is for internal housekeeping only.
* @reg_dat: data (in) register for generic GPIO
* @reg_set: output set register (out=high) for generic GPIO
* @reg_clr: output clear register (out=low) for generic GPIO
* @reg_dir: direction setting register for generic GPIO
* @bgpio_dir_inverted: indicates that the direction register is inverted
* (gpiolib private state variable)
* @bgpio_bits: number of register bits used for a generic GPIO i.e.
* <register width> * 8
* @bgpio_lock: used to lock chip->bgpio_data. Also, this is needed to keep
* shadowed and real data registers writes together.
* @bgpio_data: shadowed data register for generic GPIO to clear/set bits
* safely.
* @bgpio_dir: shadowed direction register for generic GPIO to clear/set
* direction safely.
*
* A gpio_chip can help platforms abstract various sources of GPIOs so
* they can all be accessed through a common programing interface.
* Example sources would be SOC controllers, FPGAs, multifunction
* chips, dedicated GPIO expanders, and so on.
*
* Each chip controls a number of signals, identified in method calls
* by "offset" values in the range 0..(@ngpio - 1). When those signals
* are referenced through calls like gpio_get_value(gpio), the offset
* is calculated by subtracting @base from the gpio number.
*/
struct gpio_chip {
const char *label;
struct gpio_device *gpiodev;
struct device *parent;
struct module *owner;
int (*request)(struct gpio_chip *chip,
unsigned offset);
void (*free)(struct gpio_chip *chip,
unsigned offset);
int (*get_direction)(struct gpio_chip *chip,
unsigned offset);
int (*direction_input)(struct gpio_chip *chip,
unsigned offset);
int (*direction_output)(struct gpio_chip *chip,
unsigned offset, int value);
int (*get)(struct gpio_chip *chip,
unsigned offset);
int (*get_multiple)(struct gpio_chip *chip,
unsigned long *mask,
unsigned long *bits);
void (*set)(struct gpio_chip *chip,
unsigned offset, int value);
void (*set_multiple)(struct gpio_chip *chip,
unsigned long *mask,
unsigned long *bits);
int (*set_config)(struct gpio_chip *chip,
unsigned offset,
unsigned long config);
int (*to_irq)(struct gpio_chip *chip,
unsigned offset);
void (*dbg_show)(struct seq_file *s,
struct gpio_chip *chip);
int base;
u16 ngpio;
const char *const *names;
bool can_sleep;
#if IS_ENABLED(CONFIG_GPIO_GENERIC)
unsigned long (*read_reg)(void __iomem *reg);
void (*write_reg)(void __iomem *reg, unsigned long data);
bool be_bits;
void __iomem *reg_dat;
void __iomem *reg_set;
void __iomem *reg_clr;
void __iomem *reg_dir;
bool bgpio_dir_inverted;
int bgpio_bits;
spinlock_t bgpio_lock;
unsigned long bgpio_data;
unsigned long bgpio_dir;
#endif
#ifdef CONFIG_GPIOLIB_IRQCHIP
/*
* With CONFIG_GPIOLIB_IRQCHIP we get an irqchip inside the gpiolib
* to handle IRQs for most practical cases.
*/
/**
* @irq:
*
* Integrates interrupt chip functionality with the GPIO chip. Can be
* used to handle IRQs for most practical cases.
*/
struct gpio_irq_chip irq;
#endif
/**
* @need_valid_mask:
*
* If set core allocates @valid_mask with all bits set to one.
*/
bool need_valid_mask;
/**
* @valid_mask:
*
* If not %NULL holds bitmask of GPIOs which are valid to be used
* from the chip.
*/
unsigned long *valid_mask;
#if defined(CONFIG_OF_GPIO)
/*
* If CONFIG_OF is enabled, then all GPIO controllers described in the
* device tree automatically may have an OF translation
*/
/**
* @of_node:
*
* Pointer to a device tree node representing this GPIO controller.
*/
struct device_node *of_node;
/**
* @of_gpio_n_cells:
*
* Number of cells used to form the GPIO specifier.
*/
unsigned int of_gpio_n_cells;
/**
* @of_xlate:
*
* Callback to translate a device tree GPIO specifier into a chip-
* relative GPIO number and flags.
*/
int (*of_xlate)(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec, u32 *flags);
#endif
};
extern const char *gpiochip_is_requested(struct gpio_chip *chip,
unsigned offset);
/* add/remove chips */
extern int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
struct lock_class_key *lock_key,
struct lock_class_key *request_key);
/**
* gpiochip_add_data() - register a gpio_chip
* @chip: the chip to register, with chip->base initialized
* @data: driver-private data associated with this chip
*
* Context: potentially before irqs will work
*
* When gpiochip_add_data() is called very early during boot, so that GPIOs
* can be freely used, the chip->parent device must be registered before
* the gpio framework's arch_initcall(). Otherwise sysfs initialization
* for GPIOs will fail rudely.
*
* gpiochip_add_data() must only be called after gpiolib initialization,
* ie after core_initcall().
*
* If chip->base is negative, this requests dynamic assignment of
* a range of valid GPIOs.
*
* Returns:
* A negative errno if the chip can't be registered, such as because the
* chip->base is invalid or already associated with a different chip.
* Otherwise it returns zero as a success code.
*/
#ifdef CONFIG_LOCKDEP
#define gpiochip_add_data(chip, data) ({ \
static struct lock_class_key lock_key; \
static struct lock_class_key request_key; \
gpiochip_add_data_with_key(chip, data, &lock_key, \
&request_key); \
})
#else
#define gpiochip_add_data(chip, data) gpiochip_add_data_with_key(chip, data, NULL, NULL)
#endif
static inline int gpiochip_add(struct gpio_chip *chip)
{
return gpiochip_add_data(chip, NULL);
}
extern void gpiochip_remove(struct gpio_chip *chip);
extern int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
void *data);
extern void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip);
extern struct gpio_chip *gpiochip_find(void *data,
int (*match)(struct gpio_chip *chip, void *data));
/* lock/unlock as IRQ */
int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset);
void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset);
bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset);
/* Line status inquiry for drivers */
bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset);
bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset);
/* Sleep persistence inquiry for drivers */
bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset);
bool gpiochip_line_is_valid(const struct gpio_chip *chip, unsigned int offset);
/* get driver data */
void *gpiochip_get_data(struct gpio_chip *chip);
struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
struct bgpio_pdata {
const char *label;
int base;
int ngpio;
};
#if IS_ENABLED(CONFIG_GPIO_GENERIC)
int bgpio_init(struct gpio_chip *gc, struct device *dev,
unsigned long sz, void __iomem *dat, void __iomem *set,
void __iomem *clr, void __iomem *dirout, void __iomem *dirin,
unsigned long flags);
#define BGPIOF_BIG_ENDIAN BIT(0)
#define BGPIOF_UNREADABLE_REG_SET BIT(1) /* reg_set is unreadable */
#define BGPIOF_UNREADABLE_REG_DIR BIT(2) /* reg_dir is unreadable */
#define BGPIOF_BIG_ENDIAN_BYTE_ORDER BIT(3)
#define BGPIOF_READ_OUTPUT_REG_SET BIT(4) /* reg_set stores output value */
#define BGPIOF_NO_OUTPUT BIT(5) /* only input */
#endif
#ifdef CONFIG_GPIOLIB_IRQCHIP
int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hwirq);
void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq);
void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int parent_irq,
irq_flow_handler_t parent_handler);
void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int parent_irq);
int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int first_irq,
irq_flow_handler_t handler,
unsigned int type,
bool threaded,
struct lock_class_key *lock_key,
struct lock_class_key *request_key);
bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
unsigned int offset);
#ifdef CONFIG_LOCKDEP
/*
* Lockdep requires that each irqchip instance be created with a
* unique key so as to avoid unnecessary warnings. This upfront
* boilerplate static inlines provides such a key for each
* unique instance.
*/
static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int first_irq,
irq_flow_handler_t handler,
unsigned int type)
{
static struct lock_class_key lock_key;
static struct lock_class_key request_key;
return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
handler, type, false,
&lock_key, &request_key);
}
static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int first_irq,
irq_flow_handler_t handler,
unsigned int type)
{
static struct lock_class_key lock_key;
static struct lock_class_key request_key;
return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
handler, type, true,
&lock_key, &request_key);
}
#else
static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int first_irq,
irq_flow_handler_t handler,
unsigned int type)
{
return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
handler, type, false, NULL, NULL);
}
static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
struct irq_chip *irqchip,
unsigned int first_irq,
irq_flow_handler_t handler,
unsigned int type)
{
return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
handler, type, true, NULL, NULL);
}
#endif /* CONFIG_LOCKDEP */
#endif /* CONFIG_GPIOLIB_IRQCHIP */
int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset);
void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset);
int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
unsigned long config);
#ifdef CONFIG_PINCTRL
/**
* struct gpio_pin_range - pin range controlled by a gpio chip
* @node: list for maintaining set of pin ranges, used internally
* @pctldev: pinctrl device which handles corresponding pins
* @range: actual range of pins controlled by a gpio controller
*/
struct gpio_pin_range {
struct list_head node;
struct pinctrl_dev *pctldev;
struct pinctrl_gpio_range range;
};
int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
unsigned int gpio_offset, unsigned int pin_offset,
unsigned int npins);
int gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group);
void gpiochip_remove_pin_ranges(struct gpio_chip *chip);
#else
static inline int
gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
unsigned int gpio_offset, unsigned int pin_offset,
unsigned int npins)
{
return 0;
}
static inline int
gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group)
{
return 0;
}
static inline void
gpiochip_remove_pin_ranges(struct gpio_chip *chip)
{
}
#endif /* CONFIG_PINCTRL */
struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
const char *label);
void gpiochip_free_own_desc(struct gpio_desc *desc);
#else /* CONFIG_GPIOLIB */
static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
{
/* GPIO can never have been requested */
WARN_ON(1);
return ERR_PTR(-ENODEV);
}
#endif /* CONFIG_GPIOLIB */
#endif