linux/drivers/pinctrl/pinctrl-mcp23s08.h
Andreas Kaessens 4e73bfa3ee pinctrl: mcp23s08: Add optional reset GPIO
The MCP23x port expander RESET# line can be connected to a host GPIO.
The optional reset-gpio must be set to LOW if the reset is asserted
at probing time.

On page 5 in the datasheet [0] the "Device Active After Reset high"
time is specified at 0 µs. Therefore no waiting is needed after the
reset transition.

[0] https://ww1.microchip.com/downloads/en/DeviceDoc/20001952C.pdf

Signed-off-by: Andreas Kaessens <akaessens@gmail.com>
Signed-off-by: Darian Biastoch <d.biastoch@gmail.com>
Link: https://lore.kernel.org/r/20210610132438.3085841-1-akaessens@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-06-12 01:58:10 +02:00

54 lines
1.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/* MCP23S08 SPI/I2C GPIO driver */
#include <linux/gpio/driver.h>
#include <linux/irq.h>
#include <linux/mutex.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/types.h>
/*
* MCP types supported by driver
*/
#define MCP_TYPE_S08 1
#define MCP_TYPE_S17 2
#define MCP_TYPE_008 3
#define MCP_TYPE_017 4
#define MCP_TYPE_S18 5
#define MCP_TYPE_018 6
struct device;
struct regmap;
struct pinctrl_dev;
struct mcp23s08 {
u8 addr;
bool irq_active_high;
bool reg_shift;
u16 irq_rise;
u16 irq_fall;
int irq;
bool irq_controller;
int cached_gpio;
/* lock protects regmap access with bypass/cache flags */
struct mutex lock;
struct gpio_chip chip;
struct irq_chip irq_chip;
struct regmap *regmap;
struct device *dev;
struct pinctrl_dev *pctldev;
struct pinctrl_desc pinctrl_desc;
struct gpio_desc *reset_gpio;
};
extern const struct regmap_config mcp23x08_regmap;
extern const struct regmap_config mcp23x17_regmap;
int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
unsigned int addr, unsigned int type, unsigned int base);