alistair23-linux/drivers/gpio/gpio-pca953x.c
Linus Torvalds bbfe0d6b8b This is the bulk of changes in the GPIO subsystem for the
v5.4 kernel cycle.
 
 Core changes:
 
 - Support hierarchical GPIO irqchips. We now have three
   consumers that can use this: Intel IXP4xx, ThunderX and
   Qualcomm SPMI GPIO (in the pinctrl subsystem). The support
   code has been long in the making and hashed out so it should
   be easily adaptable for all hierarchical irqchip parents.
   The code only gets compiled in if hierarchical irqchip
   is used at the topmost irq controller at least, as the
   hierarchical irqchip requires strict hierarchy all the
   way up in the system.
 
 - Determine the need for a "valid_mask" for GPIO lines on the
   gpio_chip and conversely for the "valid_mask" for the GPIO
   interrupt chip interrupt lines by looking for a
   .init_valid_mask() callback in the main chip or GPIO interrupt
   chip respectively. Allocate it with bitmap_alloc().
 
 - Isolate the device tree/open firmware GPIO description code
   out in its own file properly.
 
 - Isolate the ACPI GPIO description code out in its own file
   properly.
 
 - Drop a whole lot of #ifdef:s in the main includes: it does
   not hurt to keep the include items around, and we get
   quicker and clearer compile failures if the appropriate
   kernel symbols are not selected for drivers.
 
 New/deleted drivers:
 
 - New driver for Aspeed SGPIO.
 
 - The KS8695 driver is deleted as the platform gets deleted
   from arch/arm in this kernel cycle.
 
 - The Cirrus Logic Madera driver now supports CS47L92 and
   CS47L15.
 
 - The Freescale MPC8xxx now supports LS1028A and LS1088A.
 
 Driver improvements:
 
 - We pass the GPIO irqchip intialization by directly filling
   in the struct instead of using set-up functions (the new
   way) for Intel MID, Lynxpoint, Merrifield, XLP, HLWD, Aspeed,
   ZX, VF610, TQMX86, MT7621, Zynq and EP93xx.
 
 Out-of-band changes:
 
 - Fix a GPIO header inclusion in Unicore - no response from
   maintainer.
 
 - Drop FMC subsystem from MAINTAINERS - was deleted in the
   GPIO tree last cycle so let's mop up the shards.
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Merge tag 'gpio-v5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of changes in the GPIO subsystem for the v5.4 kernel
  cycle.

  Core changes:

   - Support hierarchical GPIO irqchips.

     We now have three consumers that can use this: Intel IXP4xx,
     ThunderX and Qualcomm SPMI GPIO (in the pinctrl subsystem).

     The support code has been long in the making and hashed out so it
     should be easily adaptable for all hierarchical irqchip parents.
     The code only gets compiled in if hierarchical irqchip is used at
     the topmost irq controller at least, as the hierarchical irqchip
     requires strict hierarchy all the way up in the system.

   - Determine the need for a "valid_mask" for GPIO lines on the
     gpio_chip and conversely for the "valid_mask" for the GPIO
     interrupt chip interrupt lines by looking for a .init_valid_mask()
     callback in the main chip or GPIO interrupt chip respectively.
     Allocate it with bitmap_alloc().

   - Isolate the device tree/open firmware GPIO description code out in
     its own file properly.

   - Isolate the ACPI GPIO description code out in its own file
     properly.

   - Drop a whole lot of #ifdef:s in the main includes: it does not hurt
     to keep the include items around, and we get quicker and clearer
     compile failures if the appropriate kernel symbols are not selected
     for drivers.

  New/deleted drivers:

   - New driver for Aspeed SGPIO.

   - The KS8695 driver is deleted as the platform gets deleted from
     arch/arm in this kernel cycle.

   - The Cirrus Logic Madera driver now supports CS47L92 and CS47L15.

   - The Freescale MPC8xxx now supports LS1028A and LS1088A.

  Driver improvements:

   - We pass the GPIO irqchip intialization by directly filling in the
     struct instead of using set-up functions (the new way) for Intel
     MID, Lynxpoint, Merrifield, XLP, HLWD, Aspeed, ZX, VF610, TQMX86,
     MT7621, Zynq and EP93xx.

  Out-of-band changes:

   - Fix a GPIO header inclusion in Unicore - no response from
     maintainer.

   - Drop FMC subsystem from MAINTAINERS - was deleted in the GPIO tree
     last cycle so let's mop up the shards"

* tag 'gpio-v5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (82 commits)
  gpiolib: of: add a fallback for wlf,reset GPIO name
  gpio: htc-egpio: Remove unused exported htc_egpio_get_wakeup_irq()
  gpio: remove explicit comparison with 0
  gpio: creg-snps: use devm_platform_ioremap_resource() to simplify code
  gpio: devres: Switch to EXPORT_SYMBOL_GPL()
  gpio: of: Switch to EXPORT_SYMBOL_GPL()
  gpio: of: Make of_gpio_simple_xlate() private
  gpio: of: Make of_get_named_gpiod_flags() private
  gpio: aspeed: Add in ast2600 details to Aspeed driver
  gpio: aspeed: Use ngpio property from device tree if available
  gpio: aspeed: Setup irqchip dynamically
  gpio/aspeed: Fix incorrect number of banks
  gpio: aspeed: Update documentation with ast2600 controllers
  gpio: Initialize the irqchip valid_mask with a callback
  gpiolib: acpi: make acpi_can_fallback_to_crs() static
  gpio: Fix further merge errors
  gpio: Fix up merge collision in include file
  gpio: of: Normalize return code variable name
  gpio: gpiolib: Normalize return code variable name
  gpio: ep93xx: Pass irqchip when adding gpiochip
  ...
2019-09-16 14:06:50 -07:00

1217 lines
32 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* PCA953x 4/8/16/24/40 bit I/O ports
*
* Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
* Copyright (C) 2007 Marvell International Ltd.
*
* Derived from drivers/i2c/chips/pca9539.c
*/
#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_data/pca953x.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <asm/unaligned.h>
#define PCA953X_INPUT 0x00
#define PCA953X_OUTPUT 0x01
#define PCA953X_INVERT 0x02
#define PCA953X_DIRECTION 0x03
#define REG_ADDR_MASK GENMASK(5, 0)
#define REG_ADDR_EXT BIT(6)
#define REG_ADDR_AI BIT(7)
#define PCA957X_IN 0x00
#define PCA957X_INVRT 0x01
#define PCA957X_BKEN 0x02
#define PCA957X_PUPD 0x03
#define PCA957X_CFG 0x04
#define PCA957X_OUT 0x05
#define PCA957X_MSK 0x06
#define PCA957X_INTS 0x07
#define PCAL953X_OUT_STRENGTH 0x20
#define PCAL953X_IN_LATCH 0x22
#define PCAL953X_PULL_EN 0x23
#define PCAL953X_PULL_SEL 0x24
#define PCAL953X_INT_MASK 0x25
#define PCAL953X_INT_STAT 0x26
#define PCAL953X_OUT_CONF 0x27
#define PCAL6524_INT_EDGE 0x28
#define PCAL6524_INT_CLR 0x2a
#define PCAL6524_IN_STATUS 0x2b
#define PCAL6524_OUT_INDCONF 0x2c
#define PCAL6524_DEBOUNCE 0x2d
#define PCA_GPIO_MASK GENMASK(7, 0)
#define PCAL_GPIO_MASK GENMASK(4, 0)
#define PCAL_PINCTRL_MASK GENMASK(6, 5)
#define PCA_INT BIT(8)
#define PCA_PCAL BIT(9)
#define PCA_LATCH_INT (PCA_PCAL | PCA_INT)
#define PCA953X_TYPE BIT(12)
#define PCA957X_TYPE BIT(13)
#define PCA_TYPE_MASK GENMASK(15, 12)
#define PCA_CHIP_TYPE(x) ((x) & PCA_TYPE_MASK)
static const struct i2c_device_id pca953x_id[] = {
{ "pca6416", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
{ "pca9534", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9536", 4 | PCA953X_TYPE, },
{ "pca9537", 4 | PCA953X_TYPE | PCA_INT, },
{ "pca9538", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9539", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9554", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9555", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9556", 8 | PCA953X_TYPE, },
{ "pca9557", 8 | PCA953X_TYPE, },
{ "pca9574", 8 | PCA957X_TYPE | PCA_INT, },
{ "pca9575", 16 | PCA957X_TYPE | PCA_INT, },
{ "pca9698", 40 | PCA953X_TYPE, },
{ "pcal6416", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal6524", 24 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal9555a", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "max7310", 8 | PCA953X_TYPE, },
{ "max7312", 16 | PCA953X_TYPE | PCA_INT, },
{ "max7313", 16 | PCA953X_TYPE | PCA_INT, },
{ "max7315", 8 | PCA953X_TYPE | PCA_INT, },
{ "max7318", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca6107", 8 | PCA953X_TYPE | PCA_INT, },
{ "tca6408", 8 | PCA953X_TYPE | PCA_INT, },
{ "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
{ "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
{ "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
{ "tca9554", 8 | PCA953X_TYPE | PCA_INT, },
{ "xra1202", 8 | PCA953X_TYPE },
{ }
};
MODULE_DEVICE_TABLE(i2c, pca953x_id);
static const struct acpi_device_id pca953x_acpi_ids[] = {
{ "INT3491", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ }
};
MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
#define MAX_BANK 5
#define BANK_SZ 8
#define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
struct pca953x_reg_config {
int direction;
int output;
int input;
int invert;
};
static const struct pca953x_reg_config pca953x_regs = {
.direction = PCA953X_DIRECTION,
.output = PCA953X_OUTPUT,
.input = PCA953X_INPUT,
.invert = PCA953X_INVERT,
};
static const struct pca953x_reg_config pca957x_regs = {
.direction = PCA957X_CFG,
.output = PCA957X_OUT,
.input = PCA957X_IN,
.invert = PCA957X_INVRT,
};
struct pca953x_chip {
unsigned gpio_start;
struct mutex i2c_lock;
struct regmap *regmap;
#ifdef CONFIG_GPIO_PCA953X_IRQ
struct mutex irq_lock;
u8 irq_mask[MAX_BANK];
u8 irq_stat[MAX_BANK];
u8 irq_trig_raise[MAX_BANK];
u8 irq_trig_fall[MAX_BANK];
struct irq_chip irq_chip;
#endif
atomic_t wakeup_path;
struct i2c_client *client;
struct gpio_chip gpio_chip;
const char *const *names;
unsigned long driver_data;
struct regulator *regulator;
const struct pca953x_reg_config *regs;
};
static int pca953x_bank_shift(struct pca953x_chip *chip)
{
return fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
}
#define PCA953x_BANK_INPUT BIT(0)
#define PCA953x_BANK_OUTPUT BIT(1)
#define PCA953x_BANK_POLARITY BIT(2)
#define PCA953x_BANK_CONFIG BIT(3)
#define PCA957x_BANK_INPUT BIT(0)
#define PCA957x_BANK_POLARITY BIT(1)
#define PCA957x_BANK_BUSHOLD BIT(2)
#define PCA957x_BANK_CONFIG BIT(4)
#define PCA957x_BANK_OUTPUT BIT(5)
#define PCAL9xxx_BANK_IN_LATCH BIT(8 + 2)
#define PCAL9xxx_BANK_PULL_EN BIT(8 + 3)
#define PCAL9xxx_BANK_PULL_SEL BIT(8 + 4)
#define PCAL9xxx_BANK_IRQ_MASK BIT(8 + 5)
#define PCAL9xxx_BANK_IRQ_STAT BIT(8 + 6)
/*
* We care about the following registers:
* - Standard set, below 0x40, each port can be replicated up to 8 times
* - PCA953x standard
* Input port 0x00 + 0 * bank_size R
* Output port 0x00 + 1 * bank_size RW
* Polarity Inversion port 0x00 + 2 * bank_size RW
* Configuration port 0x00 + 3 * bank_size RW
* - PCA957x with mixed up registers
* Input port 0x00 + 0 * bank_size R
* Polarity Inversion port 0x00 + 1 * bank_size RW
* Bus hold port 0x00 + 2 * bank_size RW
* Configuration port 0x00 + 4 * bank_size RW
* Output port 0x00 + 5 * bank_size RW
*
* - Extended set, above 0x40, often chip specific.
* - PCAL6524/PCAL9555A with custom PCAL IRQ handling:
* Input latch register 0x40 + 2 * bank_size RW
* Pull-up/pull-down enable reg 0x40 + 3 * bank_size RW
* Pull-up/pull-down select reg 0x40 + 4 * bank_size RW
* Interrupt mask register 0x40 + 5 * bank_size RW
* Interrupt status register 0x40 + 6 * bank_size R
*
* - Registers with bit 0x80 set, the AI bit
* The bit is cleared and the registers fall into one of the
* categories above.
*/
static bool pca953x_check_register(struct pca953x_chip *chip, unsigned int reg,
u32 checkbank)
{
int bank_shift = pca953x_bank_shift(chip);
int bank = (reg & REG_ADDR_MASK) >> bank_shift;
int offset = reg & (BIT(bank_shift) - 1);
/* Special PCAL extended register check. */
if (reg & REG_ADDR_EXT) {
if (!(chip->driver_data & PCA_PCAL))
return false;
bank += 8;
}
/* Register is not in the matching bank. */
if (!(BIT(bank) & checkbank))
return false;
/* Register is not within allowed range of bank. */
if (offset >= NBANK(chip))
return false;
return true;
}
static bool pca953x_readable_register(struct device *dev, unsigned int reg)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
u32 bank;
if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE) {
bank = PCA953x_BANK_INPUT | PCA953x_BANK_OUTPUT |
PCA953x_BANK_POLARITY | PCA953x_BANK_CONFIG;
} else {
bank = PCA957x_BANK_INPUT | PCA957x_BANK_OUTPUT |
PCA957x_BANK_POLARITY | PCA957x_BANK_CONFIG |
PCA957x_BANK_BUSHOLD;
}
if (chip->driver_data & PCA_PCAL) {
bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_PULL_EN |
PCAL9xxx_BANK_PULL_SEL | PCAL9xxx_BANK_IRQ_MASK |
PCAL9xxx_BANK_IRQ_STAT;
}
return pca953x_check_register(chip, reg, bank);
}
static bool pca953x_writeable_register(struct device *dev, unsigned int reg)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
u32 bank;
if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE) {
bank = PCA953x_BANK_OUTPUT | PCA953x_BANK_POLARITY |
PCA953x_BANK_CONFIG;
} else {
bank = PCA957x_BANK_OUTPUT | PCA957x_BANK_POLARITY |
PCA957x_BANK_CONFIG | PCA957x_BANK_BUSHOLD;
}
if (chip->driver_data & PCA_PCAL)
bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_PULL_EN |
PCAL9xxx_BANK_PULL_SEL | PCAL9xxx_BANK_IRQ_MASK;
return pca953x_check_register(chip, reg, bank);
}
static bool pca953x_volatile_register(struct device *dev, unsigned int reg)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
u32 bank;
if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)
bank = PCA953x_BANK_INPUT;
else
bank = PCA957x_BANK_INPUT;
if (chip->driver_data & PCA_PCAL)
bank |= PCAL9xxx_BANK_IRQ_STAT;
return pca953x_check_register(chip, reg, bank);
}
static const struct regmap_config pca953x_i2c_regmap = {
.reg_bits = 8,
.val_bits = 8,
.readable_reg = pca953x_readable_register,
.writeable_reg = pca953x_writeable_register,
.volatile_reg = pca953x_volatile_register,
.cache_type = REGCACHE_RBTREE,
/* REVISIT: should be 0x7f but some 24 bit chips use REG_ADDR_AI */
.max_register = 0xff,
};
static u8 pca953x_recalc_addr(struct pca953x_chip *chip, int reg, int off,
bool write, bool addrinc)
{
int bank_shift = pca953x_bank_shift(chip);
int addr = (reg & PCAL_GPIO_MASK) << bank_shift;
int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1;
u8 regaddr = pinctrl | addr | (off / BANK_SZ);
/* Single byte read doesn't need AI bit set. */
if (!addrinc)
return regaddr;
/* Chips with 24 and more GPIOs always support Auto Increment */
if (write && NBANK(chip) > 2)
regaddr |= REG_ADDR_AI;
/* PCA9575 needs address-increment on multi-byte writes */
if (PCA_CHIP_TYPE(chip->driver_data) == PCA957X_TYPE)
regaddr |= REG_ADDR_AI;
return regaddr;
}
static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
{
u8 regaddr = pca953x_recalc_addr(chip, reg, 0, true, true);
int ret;
ret = regmap_bulk_write(chip->regmap, regaddr, val, NBANK(chip));
if (ret < 0) {
dev_err(&chip->client->dev, "failed writing register\n");
return ret;
}
return 0;
}
static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)
{
u8 regaddr = pca953x_recalc_addr(chip, reg, 0, false, true);
int ret;
ret = regmap_bulk_read(chip->regmap, regaddr, val, NBANK(chip));
if (ret < 0) {
dev_err(&chip->client->dev, "failed reading register\n");
return ret;
}
return 0;
}
static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 dirreg = pca953x_recalc_addr(chip, chip->regs->direction, off,
true, false);
u8 bit = BIT(off % BANK_SZ);
int ret;
mutex_lock(&chip->i2c_lock);
ret = regmap_write_bits(chip->regmap, dirreg, bit, bit);
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_direction_output(struct gpio_chip *gc,
unsigned off, int val)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 dirreg = pca953x_recalc_addr(chip, chip->regs->direction, off,
true, false);
u8 outreg = pca953x_recalc_addr(chip, chip->regs->output, off,
true, false);
u8 bit = BIT(off % BANK_SZ);
int ret;
mutex_lock(&chip->i2c_lock);
/* set output level */
ret = regmap_write_bits(chip->regmap, outreg, bit, val ? bit : 0);
if (ret)
goto exit;
/* then direction */
ret = regmap_write_bits(chip->regmap, dirreg, bit, 0);
exit:
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 inreg = pca953x_recalc_addr(chip, chip->regs->input, off,
true, false);
u8 bit = BIT(off % BANK_SZ);
u32 reg_val;
int ret;
mutex_lock(&chip->i2c_lock);
ret = regmap_read(chip->regmap, inreg, &reg_val);
mutex_unlock(&chip->i2c_lock);
if (ret < 0) {
/* NOTE: diagnostic already emitted; that's all we should
* do unless gpio_*_value_cansleep() calls become different
* from their nonsleeping siblings (and report faults).
*/
return 0;
}
return !!(reg_val & bit);
}
static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 outreg = pca953x_recalc_addr(chip, chip->regs->output, off,
true, false);
u8 bit = BIT(off % BANK_SZ);
mutex_lock(&chip->i2c_lock);
regmap_write_bits(chip->regmap, outreg, bit, val ? bit : 0);
mutex_unlock(&chip->i2c_lock);
}
static int pca953x_gpio_get_direction(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 dirreg = pca953x_recalc_addr(chip, chip->regs->direction, off,
true, false);
u8 bit = BIT(off % BANK_SZ);
u32 reg_val;
int ret;
mutex_lock(&chip->i2c_lock);
ret = regmap_read(chip->regmap, dirreg, &reg_val);
mutex_unlock(&chip->i2c_lock);
if (ret < 0)
return ret;
return !!(reg_val & bit);
}
static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
unsigned long *mask, unsigned long *bits)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
unsigned int bank_mask, bank_val;
int bank;
u8 reg_val[MAX_BANK];
int ret;
mutex_lock(&chip->i2c_lock);
ret = pca953x_read_regs(chip, chip->regs->output, reg_val);
if (ret)
goto exit;
for (bank = 0; bank < NBANK(chip); bank++) {
bank_mask = mask[bank / sizeof(*mask)] >>
((bank % sizeof(*mask)) * 8);
if (bank_mask) {
bank_val = bits[bank / sizeof(*bits)] >>
((bank % sizeof(*bits)) * 8);
bank_val &= bank_mask;
reg_val[bank] = (reg_val[bank] & ~bank_mask) | bank_val;
}
}
pca953x_write_regs(chip, chip->regs->output, reg_val);
exit:
mutex_unlock(&chip->i2c_lock);
}
static int pca953x_gpio_set_pull_up_down(struct pca953x_chip *chip,
unsigned int offset,
unsigned long config)
{
u8 pull_en_reg = pca953x_recalc_addr(chip, PCAL953X_PULL_EN, offset,
true, false);
u8 pull_sel_reg = pca953x_recalc_addr(chip, PCAL953X_PULL_SEL, offset,
true, false);
u8 bit = BIT(offset % BANK_SZ);
int ret;
/*
* pull-up/pull-down configuration requires PCAL extended
* registers
*/
if (!(chip->driver_data & PCA_PCAL))
return -ENOTSUPP;
mutex_lock(&chip->i2c_lock);
/* Disable pull-up/pull-down */
ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, 0);
if (ret)
goto exit;
/* Configure pull-up/pull-down */
if (config == PIN_CONFIG_BIAS_PULL_UP)
ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, bit);
else if (config == PIN_CONFIG_BIAS_PULL_DOWN)
ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, 0);
if (ret)
goto exit;
/* Enable pull-up/pull-down */
ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, bit);
exit:
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
unsigned long config)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
switch (config) {
case PIN_CONFIG_BIAS_PULL_UP:
case PIN_CONFIG_BIAS_PULL_DOWN:
return pca953x_gpio_set_pull_up_down(chip, offset, config);
default:
return -ENOTSUPP;
}
}
static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
{
struct gpio_chip *gc;
gc = &chip->gpio_chip;
gc->direction_input = pca953x_gpio_direction_input;
gc->direction_output = pca953x_gpio_direction_output;
gc->get = pca953x_gpio_get_value;
gc->set = pca953x_gpio_set_value;
gc->get_direction = pca953x_gpio_get_direction;
gc->set_multiple = pca953x_gpio_set_multiple;
gc->set_config = pca953x_gpio_set_config;
gc->can_sleep = true;
gc->base = chip->gpio_start;
gc->ngpio = gpios;
gc->label = dev_name(&chip->client->dev);
gc->parent = &chip->client->dev;
gc->owner = THIS_MODULE;
gc->names = chip->names;
}
#ifdef CONFIG_GPIO_PCA953X_IRQ
static void pca953x_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
chip->irq_mask[d->hwirq / BANK_SZ] &= ~BIT(d->hwirq % BANK_SZ);
}
static void pca953x_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
chip->irq_mask[d->hwirq / BANK_SZ] |= BIT(d->hwirq % BANK_SZ);
}
static int pca953x_irq_set_wake(struct irq_data *d, unsigned int on)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
if (on)
atomic_inc(&chip->wakeup_path);
else
atomic_dec(&chip->wakeup_path);
return irq_set_irq_wake(chip->client->irq, on);
}
static void pca953x_irq_bus_lock(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
mutex_lock(&chip->irq_lock);
}
static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 new_irqs;
int level, i;
u8 invert_irq_mask[MAX_BANK];
u8 reg_direction[MAX_BANK];
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
if (chip->driver_data & PCA_PCAL) {
/* Enable latch on interrupt-enabled inputs */
pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
for (i = 0; i < NBANK(chip); i++)
invert_irq_mask[i] = ~chip->irq_mask[i];
/* Unmask enabled interrupts */
pca953x_write_regs(chip, PCAL953X_INT_MASK, invert_irq_mask);
}
/* Look for any newly setup interrupt */
for (i = 0; i < NBANK(chip); i++) {
new_irqs = chip->irq_trig_fall[i] | chip->irq_trig_raise[i];
new_irqs &= reg_direction[i];
while (new_irqs) {
level = __ffs(new_irqs);
pca953x_gpio_direction_input(&chip->gpio_chip,
level + (BANK_SZ * i));
new_irqs &= ~(1 << level);
}
}
mutex_unlock(&chip->irq_lock);
}
static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
int bank_nb = d->hwirq / BANK_SZ;
u8 mask = BIT(d->hwirq % BANK_SZ);
if (!(type & IRQ_TYPE_EDGE_BOTH)) {
dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
d->irq, type);
return -EINVAL;
}
if (type & IRQ_TYPE_EDGE_FALLING)
chip->irq_trig_fall[bank_nb] |= mask;
else
chip->irq_trig_fall[bank_nb] &= ~mask;
if (type & IRQ_TYPE_EDGE_RISING)
chip->irq_trig_raise[bank_nb] |= mask;
else
chip->irq_trig_raise[bank_nb] &= ~mask;
return 0;
}
static void pca953x_irq_shutdown(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 mask = BIT(d->hwirq % BANK_SZ);
chip->irq_trig_raise[d->hwirq / BANK_SZ] &= ~mask;
chip->irq_trig_fall[d->hwirq / BANK_SZ] &= ~mask;
}
static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
{
u8 cur_stat[MAX_BANK];
u8 old_stat[MAX_BANK];
bool pending_seen = false;
bool trigger_seen = false;
u8 trigger[MAX_BANK];
u8 reg_direction[MAX_BANK];
int ret, i;
if (chip->driver_data & PCA_PCAL) {
/* Read the current interrupt status from the device */
ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
if (ret)
return false;
/* Check latched inputs and clear interrupt status */
ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
if (ret)
return false;
for (i = 0; i < NBANK(chip); i++) {
/* Apply filter for rising/falling edge selection */
pending[i] = (~cur_stat[i] & chip->irq_trig_fall[i]) |
(cur_stat[i] & chip->irq_trig_raise[i]);
pending[i] &= trigger[i];
if (pending[i])
pending_seen = true;
}
return pending_seen;
}
ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
if (ret)
return false;
/* Remove output pins from the equation */
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
for (i = 0; i < NBANK(chip); i++)
cur_stat[i] &= reg_direction[i];
memcpy(old_stat, chip->irq_stat, NBANK(chip));
for (i = 0; i < NBANK(chip); i++) {
trigger[i] = (cur_stat[i] ^ old_stat[i]) & chip->irq_mask[i];
if (trigger[i])
trigger_seen = true;
}
if (!trigger_seen)
return false;
memcpy(chip->irq_stat, cur_stat, NBANK(chip));
for (i = 0; i < NBANK(chip); i++) {
pending[i] = (old_stat[i] & chip->irq_trig_fall[i]) |
(cur_stat[i] & chip->irq_trig_raise[i]);
pending[i] &= trigger[i];
if (pending[i])
pending_seen = true;
}
return pending_seen;
}
static irqreturn_t pca953x_irq_handler(int irq, void *devid)
{
struct pca953x_chip *chip = devid;
u8 pending[MAX_BANK];
u8 level;
unsigned nhandled = 0;
int i;
if (!pca953x_irq_pending(chip, pending))
return IRQ_NONE;
for (i = 0; i < NBANK(chip); i++) {
while (pending[i]) {
level = __ffs(pending[i]);
handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain,
level + (BANK_SZ * i)));
pending[i] &= ~(1 << level);
nhandled++;
}
}
return (nhandled > 0) ? IRQ_HANDLED : IRQ_NONE;
}
static int pca953x_irq_setup(struct pca953x_chip *chip,
int irq_base)
{
struct i2c_client *client = chip->client;
struct irq_chip *irq_chip = &chip->irq_chip;
u8 reg_direction[MAX_BANK];
int ret, i;
if (!client->irq)
return 0;
if (irq_base == -1)
return 0;
if (!(chip->driver_data & PCA_INT))
return 0;
ret = pca953x_read_regs(chip, chip->regs->input, chip->irq_stat);
if (ret)
return ret;
/*
* There is no way to know which GPIO line generated the
* interrupt. We have to rely on the previous read for
* this purpose.
*/
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
for (i = 0; i < NBANK(chip); i++)
chip->irq_stat[i] &= reg_direction[i];
mutex_init(&chip->irq_lock);
ret = devm_request_threaded_irq(&client->dev, client->irq,
NULL, pca953x_irq_handler,
IRQF_TRIGGER_LOW | IRQF_ONESHOT |
IRQF_SHARED,
dev_name(&client->dev), chip);
if (ret) {
dev_err(&client->dev, "failed to request irq %d\n",
client->irq);
return ret;
}
irq_chip->name = dev_name(&chip->client->dev);
irq_chip->irq_mask = pca953x_irq_mask;
irq_chip->irq_unmask = pca953x_irq_unmask;
irq_chip->irq_set_wake = pca953x_irq_set_wake;
irq_chip->irq_bus_lock = pca953x_irq_bus_lock;
irq_chip->irq_bus_sync_unlock = pca953x_irq_bus_sync_unlock;
irq_chip->irq_set_type = pca953x_irq_set_type;
irq_chip->irq_shutdown = pca953x_irq_shutdown;
ret = gpiochip_irqchip_add_nested(&chip->gpio_chip, irq_chip,
irq_base, handle_simple_irq,
IRQ_TYPE_NONE);
if (ret) {
dev_err(&client->dev,
"could not connect irqchip to gpiochip\n");
return ret;
}
gpiochip_set_nested_irqchip(&chip->gpio_chip, irq_chip, client->irq);
return 0;
}
#else /* CONFIG_GPIO_PCA953X_IRQ */
static int pca953x_irq_setup(struct pca953x_chip *chip,
int irq_base)
{
struct i2c_client *client = chip->client;
if (client->irq && irq_base != -1 && (chip->driver_data & PCA_INT))
dev_warn(&client->dev, "interrupt support not compiled in\n");
return 0;
}
#endif
static int device_pca95xx_init(struct pca953x_chip *chip, u32 invert)
{
int ret;
u8 val[MAX_BANK];
ret = regcache_sync_region(chip->regmap, chip->regs->output,
chip->regs->output + NBANK(chip));
if (ret)
goto out;
ret = regcache_sync_region(chip->regmap, chip->regs->direction,
chip->regs->direction + NBANK(chip));
if (ret)
goto out;
/* set platform specific polarity inversion */
if (invert)
memset(val, 0xFF, NBANK(chip));
else
memset(val, 0, NBANK(chip));
ret = pca953x_write_regs(chip, chip->regs->invert, val);
out:
return ret;
}
static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
{
int ret;
u8 val[MAX_BANK];
ret = device_pca95xx_init(chip, invert);
if (ret)
goto out;
/* To enable register 6, 7 to control pull up and pull down */
memset(val, 0x02, NBANK(chip));
ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
if (ret)
goto out;
return 0;
out:
return ret;
}
static const struct of_device_id pca953x_dt_ids[];
static int pca953x_probe(struct i2c_client *client,
const struct i2c_device_id *i2c_id)
{
struct pca953x_platform_data *pdata;
struct pca953x_chip *chip;
int irq_base = 0;
int ret;
u32 invert = 0;
struct regulator *reg;
chip = devm_kzalloc(&client->dev,
sizeof(struct pca953x_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
pdata = dev_get_platdata(&client->dev);
if (pdata) {
irq_base = pdata->irq_base;
chip->gpio_start = pdata->gpio_base;
invert = pdata->invert;
chip->names = pdata->names;
} else {
struct gpio_desc *reset_gpio;
chip->gpio_start = -1;
irq_base = 0;
/*
* See if we need to de-assert a reset pin.
*
* There is no known ACPI-enabled platforms that are
* using "reset" GPIO. Otherwise any of those platform
* must use _DSD method with corresponding property.
*/
reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
GPIOD_OUT_LOW);
if (IS_ERR(reset_gpio))
return PTR_ERR(reset_gpio);
}
chip->client = client;
reg = devm_regulator_get(&client->dev, "vcc");
if (IS_ERR(reg)) {
ret = PTR_ERR(reg);
if (ret != -EPROBE_DEFER)
dev_err(&client->dev, "reg get err: %d\n", ret);
return ret;
}
ret = regulator_enable(reg);
if (ret) {
dev_err(&client->dev, "reg en err: %d\n", ret);
return ret;
}
chip->regulator = reg;
if (i2c_id) {
chip->driver_data = i2c_id->driver_data;
} else {
const void *match;
match = device_get_match_data(&client->dev);
if (!match) {
ret = -ENODEV;
goto err_exit;
}
chip->driver_data = (uintptr_t)match;
}
i2c_set_clientdata(client, chip);
chip->regmap = devm_regmap_init_i2c(client, &pca953x_i2c_regmap);
if (IS_ERR(chip->regmap)) {
ret = PTR_ERR(chip->regmap);
goto err_exit;
}
regcache_mark_dirty(chip->regmap);
mutex_init(&chip->i2c_lock);
/*
* In case we have an i2c-mux controlled by a GPIO provided by an
* expander using the same driver higher on the device tree, read the
* i2c adapter nesting depth and use the retrieved value as lockdep
* subclass for chip->i2c_lock.
*
* REVISIT: This solution is not complete. It protects us from lockdep
* false positives when the expander controlling the i2c-mux is on
* a different level on the device tree, but not when it's on the same
* level on a different branch (in which case the subclass number
* would be the same).
*
* TODO: Once a correct solution is developed, a similar fix should be
* applied to all other i2c-controlled GPIO expanders (and potentially
* regmap-i2c).
*/
lockdep_set_subclass(&chip->i2c_lock,
i2c_adapter_depth(client->adapter));
/* initialize cached registers from their original values.
* we can't share this chip with another i2c master.
*/
pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE) {
chip->regs = &pca953x_regs;
ret = device_pca95xx_init(chip, invert);
} else {
chip->regs = &pca957x_regs;
ret = device_pca957x_init(chip, invert);
}
if (ret)
goto err_exit;
ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
if (ret)
goto err_exit;
ret = pca953x_irq_setup(chip, irq_base);
if (ret)
goto err_exit;
if (pdata && pdata->setup) {
ret = pdata->setup(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
if (ret < 0)
dev_warn(&client->dev, "setup failed, %d\n", ret);
}
return 0;
err_exit:
regulator_disable(chip->regulator);
return ret;
}
static int pca953x_remove(struct i2c_client *client)
{
struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
struct pca953x_chip *chip = i2c_get_clientdata(client);
int ret;
if (pdata && pdata->teardown) {
ret = pdata->teardown(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
if (ret < 0)
dev_err(&client->dev, "teardown failed, %d\n", ret);
} else {
ret = 0;
}
regulator_disable(chip->regulator);
return ret;
}
#ifdef CONFIG_PM_SLEEP
static int pca953x_regcache_sync(struct device *dev)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
int ret;
/*
* The ordering between direction and output is important,
* sync these registers first and only then sync the rest.
*/
ret = regcache_sync_region(chip->regmap, chip->regs->direction,
chip->regs->direction + NBANK(chip));
if (ret) {
dev_err(dev, "Failed to sync GPIO dir registers: %d\n", ret);
return ret;
}
ret = regcache_sync_region(chip->regmap, chip->regs->output,
chip->regs->output + NBANK(chip));
if (ret) {
dev_err(dev, "Failed to sync GPIO out registers: %d\n", ret);
return ret;
}
#ifdef CONFIG_GPIO_PCA953X_IRQ
if (chip->driver_data & PCA_PCAL) {
ret = regcache_sync_region(chip->regmap, PCAL953X_IN_LATCH,
PCAL953X_IN_LATCH + NBANK(chip));
if (ret) {
dev_err(dev, "Failed to sync INT latch registers: %d\n",
ret);
return ret;
}
ret = regcache_sync_region(chip->regmap, PCAL953X_INT_MASK,
PCAL953X_INT_MASK + NBANK(chip));
if (ret) {
dev_err(dev, "Failed to sync INT mask registers: %d\n",
ret);
return ret;
}
}
#endif
return 0;
}
static int pca953x_suspend(struct device *dev)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
regcache_cache_only(chip->regmap, true);
if (atomic_read(&chip->wakeup_path))
device_set_wakeup_path(dev);
else
regulator_disable(chip->regulator);
return 0;
}
static int pca953x_resume(struct device *dev)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
int ret;
if (!atomic_read(&chip->wakeup_path)) {
ret = regulator_enable(chip->regulator);
if (ret) {
dev_err(dev, "Failed to enable regulator: %d\n", ret);
return 0;
}
}
regcache_cache_only(chip->regmap, false);
regcache_mark_dirty(chip->regmap);
ret = pca953x_regcache_sync(dev);
if (ret)
return ret;
ret = regcache_sync(chip->regmap);
if (ret) {
dev_err(dev, "Failed to restore register map: %d\n", ret);
return ret;
}
return 0;
}
#endif
/* convenience to stop overlong match-table lines */
#define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
#define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
static const struct of_device_id pca953x_dt_ids[] = {
{ .compatible = "nxp,pca6416", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
{ .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
{ .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
{ .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
{ .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
{ .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
{ .compatible = "nxp,pcal6416", .data = OF_953X(16, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal6524", .data = OF_953X(24, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal9555a", .data = OF_953X(16, PCA_LATCH_INT), },
{ .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
{ .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "maxim,max7318", .data = OF_953X(16, PCA_INT), },
{ .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
{ .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
{ .compatible = "ti,tca9539", .data = OF_953X(16, PCA_INT), },
{ .compatible = "onnn,cat9554", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "onnn,pca9654", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
{ }
};
MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
static SIMPLE_DEV_PM_OPS(pca953x_pm_ops, pca953x_suspend, pca953x_resume);
static struct i2c_driver pca953x_driver = {
.driver = {
.name = "pca953x",
.pm = &pca953x_pm_ops,
.of_match_table = pca953x_dt_ids,
.acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
},
.probe = pca953x_probe,
.remove = pca953x_remove,
.id_table = pca953x_id,
};
static int __init pca953x_init(void)
{
return i2c_add_driver(&pca953x_driver);
}
/* register after i2c postcore initcall and before
* subsys initcalls that may rely on these GPIOs
*/
subsys_initcall(pca953x_init);
static void __exit pca953x_exit(void)
{
i2c_del_driver(&pca953x_driver);
}
module_exit(pca953x_exit);
MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
MODULE_LICENSE("GPL");