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linux-zen-server/drivers/gpio/gpio-aspeed.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2015 IBM Corp.
*
* Joel Stanley <joel@jms.id.au>
*/
#include <linux/clk.h>
#include <linux/gpio/aspeed.h>
#include <linux/gpio/driver.h>
#include <linux/hashtable.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <asm/div64.h>
/*
* These two headers aren't meant to be used by GPIO drivers. We need
* them in order to access gpio_chip_hwgpio() which we need to implement
* the aspeed specific API which allows the coprocessor to request
* access to some GPIOs and to arbitrate between coprocessor and ARM.
*/
#include <linux/gpio/consumer.h>
#include "gpiolib.h"
struct aspeed_bank_props {
unsigned int bank;
u32 input;
u32 output;
};
struct aspeed_gpio_config {
unsigned int nr_gpios;
const struct aspeed_bank_props *props;
};
/*
* @offset_timer: Maps an offset to an @timer_users index, or zero if disabled
* @timer_users: Tracks the number of users for each timer
*
* The @timer_users has four elements but the first element is unused. This is
* to simplify accounting and indexing, as a zero value in @offset_timer
* represents disabled debouncing for the GPIO. Any other value for an element
* of @offset_timer is used as an index into @timer_users. This behaviour of
* the zero value aligns with the behaviour of zero built from the timer
* configuration registers (i.e. debouncing is disabled).
*/
struct aspeed_gpio {
struct gpio_chip chip;
struct irq_chip irqc;
raw_spinlock_t lock;
void __iomem *base;
int irq;
const struct aspeed_gpio_config *config;
u8 *offset_timer;
unsigned int timer_users[4];
struct clk *clk;
u32 *dcache;
u8 *cf_copro_bankmap;
};
struct aspeed_gpio_bank {
uint16_t val_regs; /* +0: Rd: read input value, Wr: set write latch
* +4: Rd/Wr: Direction (0=in, 1=out)
*/
uint16_t rdata_reg; /* Rd: read write latch, Wr: <none> */
uint16_t irq_regs;
uint16_t debounce_regs;
uint16_t tolerance_regs;
uint16_t cmdsrc_regs;
const char names[4][3];
};
/*
* Note: The "value" register returns the input value sampled on the
* line even when the GPIO is configured as an output. Since
* that input goes through synchronizers, writing, then reading
* back may not return the written value right away.
*
* The "rdata" register returns the content of the write latch
* and thus can be used to read back what was last written
* reliably.
*/
static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 };
static const struct aspeed_gpio_copro_ops *copro_ops;
static void *copro_data;
static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
{
.val_regs = 0x0000,
.rdata_reg = 0x00c0,
.irq_regs = 0x0008,
.debounce_regs = 0x0040,
.tolerance_regs = 0x001c,
.cmdsrc_regs = 0x0060,
.names = { "A", "B", "C", "D" },
},
{
.val_regs = 0x0020,
.rdata_reg = 0x00c4,
.irq_regs = 0x0028,
.debounce_regs = 0x0048,
.tolerance_regs = 0x003c,
.cmdsrc_regs = 0x0068,
.names = { "E", "F", "G", "H" },
},
{
.val_regs = 0x0070,
.rdata_reg = 0x00c8,
.irq_regs = 0x0098,
.debounce_regs = 0x00b0,
.tolerance_regs = 0x00ac,
.cmdsrc_regs = 0x0090,
.names = { "I", "J", "K", "L" },
},
{
.val_regs = 0x0078,
.rdata_reg = 0x00cc,
.irq_regs = 0x00e8,
.debounce_regs = 0x0100,
.tolerance_regs = 0x00fc,
.cmdsrc_regs = 0x00e0,
.names = { "M", "N", "O", "P" },
},
{
.val_regs = 0x0080,
.rdata_reg = 0x00d0,
.irq_regs = 0x0118,
.debounce_regs = 0x0130,
.tolerance_regs = 0x012c,
.cmdsrc_regs = 0x0110,
.names = { "Q", "R", "S", "T" },
},
{
.val_regs = 0x0088,
.rdata_reg = 0x00d4,
.irq_regs = 0x0148,
.debounce_regs = 0x0160,
.tolerance_regs = 0x015c,
.cmdsrc_regs = 0x0140,
.names = { "U", "V", "W", "X" },
},
{
.val_regs = 0x01E0,
.rdata_reg = 0x00d8,
.irq_regs = 0x0178,
.debounce_regs = 0x0190,
.tolerance_regs = 0x018c,
.cmdsrc_regs = 0x0170,
.names = { "Y", "Z", "AA", "AB" },
},
{
.val_regs = 0x01e8,
.rdata_reg = 0x00dc,
.irq_regs = 0x01a8,
.debounce_regs = 0x01c0,
.tolerance_regs = 0x01bc,
.cmdsrc_regs = 0x01a0,
.names = { "AC", "", "", "" },
},
};
enum aspeed_gpio_reg {
reg_val,
reg_rdata,
reg_dir,
reg_irq_enable,
reg_irq_type0,
reg_irq_type1,
reg_irq_type2,
reg_irq_status,
reg_debounce_sel1,
reg_debounce_sel2,
reg_tolerance,
reg_cmdsrc0,
reg_cmdsrc1,
};
#define GPIO_VAL_VALUE 0x00
#define GPIO_VAL_DIR 0x04
#define GPIO_IRQ_ENABLE 0x00
#define GPIO_IRQ_TYPE0 0x04
#define GPIO_IRQ_TYPE1 0x08
#define GPIO_IRQ_TYPE2 0x0c
#define GPIO_IRQ_STATUS 0x10
#define GPIO_DEBOUNCE_SEL1 0x00
#define GPIO_DEBOUNCE_SEL2 0x04
#define GPIO_CMDSRC_0 0x00
#define GPIO_CMDSRC_1 0x04
#define GPIO_CMDSRC_ARM 0
#define GPIO_CMDSRC_LPC 1
#define GPIO_CMDSRC_COLDFIRE 2
#define GPIO_CMDSRC_RESERVED 3
/* This will be resolved at compile time */
static inline void __iomem *bank_reg(struct aspeed_gpio *gpio,
const struct aspeed_gpio_bank *bank,
const enum aspeed_gpio_reg reg)
{
switch (reg) {
case reg_val:
return gpio->base + bank->val_regs + GPIO_VAL_VALUE;
case reg_rdata:
return gpio->base + bank->rdata_reg;
case reg_dir:
return gpio->base + bank->val_regs + GPIO_VAL_DIR;
case reg_irq_enable:
return gpio->base + bank->irq_regs + GPIO_IRQ_ENABLE;
case reg_irq_type0:
return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE0;
case reg_irq_type1:
return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE1;
case reg_irq_type2:
return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE2;
case reg_irq_status:
return gpio->base + bank->irq_regs + GPIO_IRQ_STATUS;
case reg_debounce_sel1:
return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL1;
case reg_debounce_sel2:
return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL2;
case reg_tolerance:
return gpio->base + bank->tolerance_regs;
case reg_cmdsrc0:
return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_0;
case reg_cmdsrc1:
return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_1;
}
BUG();
}
#define GPIO_BANK(x) ((x) >> 5)
#define GPIO_OFFSET(x) ((x) & 0x1f)
#define GPIO_BIT(x) BIT(GPIO_OFFSET(x))
#define _GPIO_SET_DEBOUNCE(t, o, i) ((!!((t) & BIT(i))) << GPIO_OFFSET(o))
#define GPIO_SET_DEBOUNCE1(t, o) _GPIO_SET_DEBOUNCE(t, o, 1)
#define GPIO_SET_DEBOUNCE2(t, o) _GPIO_SET_DEBOUNCE(t, o, 0)
static const struct aspeed_gpio_bank *to_bank(unsigned int offset)
{
unsigned int bank = GPIO_BANK(offset);
WARN_ON(bank >= ARRAY_SIZE(aspeed_gpio_banks));
return &aspeed_gpio_banks[bank];
}
static inline bool is_bank_props_sentinel(const struct aspeed_bank_props *props)
{
return !(props->input || props->output);
}
static inline const struct aspeed_bank_props *find_bank_props(
struct aspeed_gpio *gpio, unsigned int offset)
{
const struct aspeed_bank_props *props = gpio->config->props;
while (!is_bank_props_sentinel(props)) {
if (props->bank == GPIO_BANK(offset))
return props;
props++;
}
return NULL;
}
static inline bool have_gpio(struct aspeed_gpio *gpio, unsigned int offset)
{
const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
const struct aspeed_gpio_bank *bank = to_bank(offset);
unsigned int group = GPIO_OFFSET(offset) / 8;
return bank->names[group][0] != '\0' &&
(!props || ((props->input | props->output) & GPIO_BIT(offset)));
}
static inline bool have_input(struct aspeed_gpio *gpio, unsigned int offset)
{
const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
return !props || (props->input & GPIO_BIT(offset));
}
#define have_irq(g, o) have_input((g), (o))
#define have_debounce(g, o) have_input((g), (o))
static inline bool have_output(struct aspeed_gpio *gpio, unsigned int offset)
{
const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
return !props || (props->output & GPIO_BIT(offset));
}
static void aspeed_gpio_change_cmd_source(struct aspeed_gpio *gpio,
const struct aspeed_gpio_bank *bank,
int bindex, int cmdsrc)
{
void __iomem *c0 = bank_reg(gpio, bank, reg_cmdsrc0);
void __iomem *c1 = bank_reg(gpio, bank, reg_cmdsrc1);
u32 bit, reg;
/*
* Each register controls 4 banks, so take the bottom 2
* bits of the bank index, and use them to select the
* right control bit (0, 8, 16 or 24).
*/
bit = BIT((bindex & 3) << 3);
/* Source 1 first to avoid illegal 11 combination */
reg = ioread32(c1);
if (cmdsrc & 2)
reg |= bit;
else
reg &= ~bit;
iowrite32(reg, c1);
/* Then Source 0 */
reg = ioread32(c0);
if (cmdsrc & 1)
reg |= bit;
else
reg &= ~bit;
iowrite32(reg, c0);
}
static bool aspeed_gpio_copro_request(struct aspeed_gpio *gpio,
unsigned int offset)
{
const struct aspeed_gpio_bank *bank = to_bank(offset);
if (!copro_ops || !gpio->cf_copro_bankmap)
return false;
if (!gpio->cf_copro_bankmap[offset >> 3])
return false;
if (!copro_ops->request_access)
return false;
/* Pause the coprocessor */
copro_ops->request_access(copro_data);
/* Change command source back to ARM */
aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3, GPIO_CMDSRC_ARM);
/* Update cache */
gpio->dcache[GPIO_BANK(offset)] = ioread32(bank_reg(gpio, bank, reg_rdata));
return true;
}
static void aspeed_gpio_copro_release(struct aspeed_gpio *gpio,
unsigned int offset)
{
const struct aspeed_gpio_bank *bank = to_bank(offset);
if (!copro_ops || !gpio->cf_copro_bankmap)
return;
if (!gpio->cf_copro_bankmap[offset >> 3])
return;
if (!copro_ops->release_access)
return;
/* Change command source back to ColdFire */
aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3,
GPIO_CMDSRC_COLDFIRE);
/* Restart the coprocessor */
copro_ops->release_access(copro_data);
}
static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
return !!(ioread32(bank_reg(gpio, bank, reg_val)) & GPIO_BIT(offset));
}
static void __aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
int val)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
void __iomem *addr;
u32 reg;
addr = bank_reg(gpio, bank, reg_val);
reg = gpio->dcache[GPIO_BANK(offset)];
if (val)
reg |= GPIO_BIT(offset);
else
reg &= ~GPIO_BIT(offset);
gpio->dcache[GPIO_BANK(offset)] = reg;
iowrite32(reg, addr);
}
static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
int val)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
unsigned long flags;
bool copro;
raw_spin_lock_irqsave(&gpio->lock, flags);
copro = aspeed_gpio_copro_request(gpio, offset);
__aspeed_gpio_set(gc, offset, val);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
}
static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
void __iomem *addr = bank_reg(gpio, bank, reg_dir);
unsigned long flags;
bool copro;
u32 reg;
if (!have_input(gpio, offset))
return -ENOTSUPP;
raw_spin_lock_irqsave(&gpio->lock, flags);
reg = ioread32(addr);
reg &= ~GPIO_BIT(offset);
copro = aspeed_gpio_copro_request(gpio, offset);
iowrite32(reg, addr);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return 0;
}
static int aspeed_gpio_dir_out(struct gpio_chip *gc,
unsigned int offset, int val)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
void __iomem *addr = bank_reg(gpio, bank, reg_dir);
unsigned long flags;
bool copro;
u32 reg;
if (!have_output(gpio, offset))
return -ENOTSUPP;
raw_spin_lock_irqsave(&gpio->lock, flags);
reg = ioread32(addr);
reg |= GPIO_BIT(offset);
copro = aspeed_gpio_copro_request(gpio, offset);
__aspeed_gpio_set(gc, offset, val);
iowrite32(reg, addr);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return 0;
}
static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
unsigned long flags;
u32 val;
if (!have_input(gpio, offset))
return GPIO_LINE_DIRECTION_OUT;
if (!have_output(gpio, offset))
return GPIO_LINE_DIRECTION_IN;
raw_spin_lock_irqsave(&gpio->lock, flags);
val = ioread32(bank_reg(gpio, bank, reg_dir)) & GPIO_BIT(offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return val ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
}
static inline int irqd_to_aspeed_gpio_data(struct irq_data *d,
struct aspeed_gpio **gpio,
const struct aspeed_gpio_bank **bank,
u32 *bit, int *offset)
{
struct aspeed_gpio *internal;
*offset = irqd_to_hwirq(d);
internal = irq_data_get_irq_chip_data(d);
/* This might be a bit of a questionable place to check */
if (!have_irq(internal, *offset))
return -ENOTSUPP;
*gpio = internal;
*bank = to_bank(*offset);
*bit = GPIO_BIT(*offset);
return 0;
}
static void aspeed_gpio_irq_ack(struct irq_data *d)
{
const struct aspeed_gpio_bank *bank;
struct aspeed_gpio *gpio;
unsigned long flags;
void __iomem *status_addr;
int rc, offset;
bool copro;
u32 bit;
rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
if (rc)
return;
status_addr = bank_reg(gpio, bank, reg_irq_status);
raw_spin_lock_irqsave(&gpio->lock, flags);
copro = aspeed_gpio_copro_request(gpio, offset);
iowrite32(bit, status_addr);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
}
static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
{
const struct aspeed_gpio_bank *bank;
struct aspeed_gpio *gpio;
unsigned long flags;
u32 reg, bit;
void __iomem *addr;
int rc, offset;
bool copro;
rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
if (rc)
return;
addr = bank_reg(gpio, bank, reg_irq_enable);
raw_spin_lock_irqsave(&gpio->lock, flags);
copro = aspeed_gpio_copro_request(gpio, offset);
reg = ioread32(addr);
if (set)
reg |= bit;
else
reg &= ~bit;
iowrite32(reg, addr);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
}
static void aspeed_gpio_irq_mask(struct irq_data *d)
{
aspeed_gpio_irq_set_mask(d, false);
}
static void aspeed_gpio_irq_unmask(struct irq_data *d)
{
aspeed_gpio_irq_set_mask(d, true);
}
static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
{
u32 type0 = 0;
u32 type1 = 0;
u32 type2 = 0;
u32 bit, reg;
const struct aspeed_gpio_bank *bank;
irq_flow_handler_t handler;
struct aspeed_gpio *gpio;
unsigned long flags;
void __iomem *addr;
int rc, offset;
bool copro;
rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
if (rc)
return -EINVAL;
switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_BOTH:
type2 |= bit;
fallthrough;
case IRQ_TYPE_EDGE_RISING:
type0 |= bit;
fallthrough;
case IRQ_TYPE_EDGE_FALLING:
handler = handle_edge_irq;
break;
case IRQ_TYPE_LEVEL_HIGH:
type0 |= bit;
fallthrough;
case IRQ_TYPE_LEVEL_LOW:
type1 |= bit;
handler = handle_level_irq;
break;
default:
return -EINVAL;
}
raw_spin_lock_irqsave(&gpio->lock, flags);
copro = aspeed_gpio_copro_request(gpio, offset);
addr = bank_reg(gpio, bank, reg_irq_type0);
reg = ioread32(addr);
reg = (reg & ~bit) | type0;
iowrite32(reg, addr);
addr = bank_reg(gpio, bank, reg_irq_type1);
reg = ioread32(addr);
reg = (reg & ~bit) | type1;
iowrite32(reg, addr);
addr = bank_reg(gpio, bank, reg_irq_type2);
reg = ioread32(addr);
reg = (reg & ~bit) | type2;
iowrite32(reg, addr);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
irq_set_handler_locked(d, handler);
return 0;
}
static void aspeed_gpio_irq_handler(struct irq_desc *desc)
{
struct gpio_chip *gc = irq_desc_get_handler_data(desc);
struct irq_chip *ic = irq_desc_get_chip(desc);
struct aspeed_gpio *data = gpiochip_get_data(gc);
unsigned int i, p, banks;
unsigned long reg;
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
chained_irq_enter(ic, desc);
banks = DIV_ROUND_UP(gpio->chip.ngpio, 32);
for (i = 0; i < banks; i++) {
const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
reg = ioread32(bank_reg(data, bank, reg_irq_status));
for_each_set_bit(p, &reg, 32)
generic_handle_domain_irq(gc->irq.domain, i * 32 + p);
}
chained_irq_exit(ic, desc);
}
static void aspeed_init_irq_valid_mask(struct gpio_chip *gc,
unsigned long *valid_mask,
unsigned int ngpios)
{
struct aspeed_gpio *gpio = gpiochip_get_data(gc);
const struct aspeed_bank_props *props = gpio->config->props;
while (!is_bank_props_sentinel(props)) {
unsigned int offset;
const unsigned long int input = props->input;
/* Pretty crummy approach, but similar to GPIO core */
for_each_clear_bit(offset, &input, 32) {
unsigned int i = props->bank * 32 + offset;
if (i >= gpio->chip.ngpio)
break;
clear_bit(i, valid_mask);
}
props++;
}
}
static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
unsigned int offset, bool enable)
{
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
unsigned long flags;
void __iomem *treg;
bool copro;
u32 val;
treg = bank_reg(gpio, to_bank(offset), reg_tolerance);
raw_spin_lock_irqsave(&gpio->lock, flags);
copro = aspeed_gpio_copro_request(gpio, offset);
val = readl(treg);
if (enable)
val |= GPIO_BIT(offset);
else
val &= ~GPIO_BIT(offset);
writel(val, treg);
if (copro)
aspeed_gpio_copro_release(gpio, offset);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return 0;
}
static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
{
if (!have_gpio(gpiochip_get_data(chip), offset))
return -ENODEV;
return pinctrl_gpio_request(chip->base + offset);
}
static void aspeed_gpio_free(struct gpio_chip *chip, unsigned int offset)
{
pinctrl_gpio_free(chip->base + offset);
}
static int usecs_to_cycles(struct aspeed_gpio *gpio, unsigned long usecs,
u32 *cycles)
{
u64 rate;
u64 n;
u32 r;
rate = clk_get_rate(gpio->clk);
if (!rate)
return -ENOTSUPP;
n = rate * usecs;
r = do_div(n, 1000000);
if (n >= U32_MAX)
return -ERANGE;
/* At least as long as the requested time */
*cycles = n + (!!r);
return 0;
}
/* Call under gpio->lock */
static int register_allocated_timer(struct aspeed_gpio *gpio,
unsigned int offset, unsigned int timer)
{
if (WARN(gpio->offset_timer[offset] != 0,
"Offset %d already allocated timer %d\n",
offset, gpio->offset_timer[offset]))
return -EINVAL;
if (WARN(gpio->timer_users[timer] == UINT_MAX,
"Timer user count would overflow\n"))
return -EPERM;
gpio->offset_timer[offset] = timer;
gpio->timer_users[timer]++;
return 0;
}
/* Call under gpio->lock */
static int unregister_allocated_timer(struct aspeed_gpio *gpio,
unsigned int offset)
{
if (WARN(gpio->offset_timer[offset] == 0,
"No timer allocated to offset %d\n", offset))
return -EINVAL;
if (WARN(gpio->timer_users[gpio->offset_timer[offset]] == 0,
"No users recorded for timer %d\n",
gpio->offset_timer[offset]))
return -EINVAL;
gpio->timer_users[gpio->offset_timer[offset]]--;
gpio->offset_timer[offset] = 0;
return 0;
}
/* Call under gpio->lock */
static inline bool timer_allocation_registered(struct aspeed_gpio *gpio,
unsigned int offset)
{
return gpio->offset_timer[offset] > 0;
}
/* Call under gpio->lock */
static void configure_timer(struct aspeed_gpio *gpio, unsigned int offset,
unsigned int timer)
{
const struct aspeed_gpio_bank *bank = to_bank(offset);
const u32 mask = GPIO_BIT(offset);
void __iomem *addr;
u32 val;
/* Note: Debounce timer isn't under control of the command
* source registers, so no need to sync with the coprocessor
*/
addr = bank_reg(gpio, bank, reg_debounce_sel1);
val = ioread32(addr);
iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE1(timer, offset), addr);
addr = bank_reg(gpio, bank, reg_debounce_sel2);
val = ioread32(addr);
iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE2(timer, offset), addr);
}
static int enable_debounce(struct gpio_chip *chip, unsigned int offset,
unsigned long usecs)
{
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
u32 requested_cycles;
unsigned long flags;
int rc;
int i;
if (!gpio->clk)
return -EINVAL;
rc = usecs_to_cycles(gpio, usecs, &requested_cycles);
if (rc < 0) {
dev_warn(chip->parent, "Failed to convert %luus to cycles at %luHz: %d\n",
usecs, clk_get_rate(gpio->clk), rc);
return rc;
}
raw_spin_lock_irqsave(&gpio->lock, flags);
if (timer_allocation_registered(gpio, offset)) {
rc = unregister_allocated_timer(gpio, offset);
if (rc < 0)
goto out;
}
/* Try to find a timer already configured for the debounce period */
for (i = 1; i < ARRAY_SIZE(debounce_timers); i++) {
u32 cycles;
cycles = ioread32(gpio->base + debounce_timers[i]);
if (requested_cycles == cycles)
break;
}
if (i == ARRAY_SIZE(debounce_timers)) {
int j;
/*
* As there are no timers configured for the requested debounce
* period, find an unused timer instead
*/
for (j = 1; j < ARRAY_SIZE(gpio->timer_users); j++) {
if (gpio->timer_users[j] == 0)
break;
}
if (j == ARRAY_SIZE(gpio->timer_users)) {
dev_warn(chip->parent,
"Debounce timers exhausted, cannot debounce for period %luus\n",
usecs);
rc = -EPERM;
/*
* We already adjusted the accounting to remove @offset
* as a user of its previous timer, so also configure
* the hardware so @offset has timers disabled for
* consistency.
*/
configure_timer(gpio, offset, 0);
goto out;
}
i = j;
iowrite32(requested_cycles, gpio->base + debounce_timers[i]);
}
if (WARN(i == 0, "Cannot register index of disabled timer\n")) {
rc = -EINVAL;
goto out;
}
register_allocated_timer(gpio, offset, i);
configure_timer(gpio, offset, i);
out:
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return rc;
}
static int disable_debounce(struct gpio_chip *chip, unsigned int offset)
{
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
unsigned long flags;
int rc;
raw_spin_lock_irqsave(&gpio->lock, flags);
rc = unregister_allocated_timer(gpio, offset);
if (!rc)
configure_timer(gpio, offset, 0);
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return rc;
}
static int set_debounce(struct gpio_chip *chip, unsigned int offset,
unsigned long usecs)
{
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
if (!have_debounce(gpio, offset))
return -ENOTSUPP;
if (usecs)
return enable_debounce(chip, offset, usecs);
return disable_debounce(chip, offset);
}
static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
{
unsigned long param = pinconf_to_config_param(config);
u32 arg = pinconf_to_config_argument(config);
if (param == PIN_CONFIG_INPUT_DEBOUNCE)
return set_debounce(chip, offset, arg);
else if (param == PIN_CONFIG_BIAS_DISABLE ||
param == PIN_CONFIG_BIAS_PULL_DOWN ||
param == PIN_CONFIG_DRIVE_STRENGTH)
return pinctrl_gpio_set_config(offset, config);
else if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN ||
param == PIN_CONFIG_DRIVE_OPEN_SOURCE)
/* Return -ENOTSUPP to trigger emulation, as per datasheet */
return -ENOTSUPP;
else if (param == PIN_CONFIG_PERSIST_STATE)
return aspeed_gpio_reset_tolerance(chip, offset, arg);
return -ENOTSUPP;
}
/**
* aspeed_gpio_copro_set_ops - Sets the callbacks used for handshaking with
* the coprocessor for shared GPIO banks
* @ops: The callbacks
* @data: Pointer passed back to the callbacks
*/
int aspeed_gpio_copro_set_ops(const struct aspeed_gpio_copro_ops *ops, void *data)
{
copro_data = data;
copro_ops = ops;
return 0;
}
EXPORT_SYMBOL_GPL(aspeed_gpio_copro_set_ops);
/**
* aspeed_gpio_copro_grab_gpio - Mark a GPIO used by the coprocessor. The entire
* bank gets marked and any access from the ARM will
* result in handshaking via callbacks.
* @desc: The GPIO to be marked
* @vreg_offset: If non-NULL, returns the value register offset in the GPIO space
* @dreg_offset: If non-NULL, returns the data latch register offset in the GPIO space
* @bit: If non-NULL, returns the bit number of the GPIO in the registers
*/
int aspeed_gpio_copro_grab_gpio(struct gpio_desc *desc,
u16 *vreg_offset, u16 *dreg_offset, u8 *bit)
{
struct gpio_chip *chip = gpiod_to_chip(desc);
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
unsigned long flags;
if (!gpio->cf_copro_bankmap)
gpio->cf_copro_bankmap = kzalloc(gpio->chip.ngpio >> 3, GFP_KERNEL);
if (!gpio->cf_copro_bankmap)
return -ENOMEM;
if (offset < 0 || offset > gpio->chip.ngpio)
return -EINVAL;
bindex = offset >> 3;
raw_spin_lock_irqsave(&gpio->lock, flags);
/* Sanity check, this shouldn't happen */
if (gpio->cf_copro_bankmap[bindex] == 0xff) {
rc = -EIO;
goto bail;
}
gpio->cf_copro_bankmap[bindex]++;
/* Switch command source */
if (gpio->cf_copro_bankmap[bindex] == 1)
aspeed_gpio_change_cmd_source(gpio, bank, bindex,
GPIO_CMDSRC_COLDFIRE);
if (vreg_offset)
*vreg_offset = bank->val_regs;
if (dreg_offset)
*dreg_offset = bank->rdata_reg;
if (bit)
*bit = GPIO_OFFSET(offset);
bail:
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return rc;
}
EXPORT_SYMBOL_GPL(aspeed_gpio_copro_grab_gpio);
/**
* aspeed_gpio_copro_release_gpio - Unmark a GPIO used by the coprocessor.
* @desc: The GPIO to be marked
*/
int aspeed_gpio_copro_release_gpio(struct gpio_desc *desc)
{
struct gpio_chip *chip = gpiod_to_chip(desc);
struct aspeed_gpio *gpio = gpiochip_get_data(chip);
int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
const struct aspeed_gpio_bank *bank = to_bank(offset);
unsigned long flags;
if (!gpio->cf_copro_bankmap)
return -ENXIO;
if (offset < 0 || offset > gpio->chip.ngpio)
return -EINVAL;
bindex = offset >> 3;
raw_spin_lock_irqsave(&gpio->lock, flags);
/* Sanity check, this shouldn't happen */
if (gpio->cf_copro_bankmap[bindex] == 0) {
rc = -EIO;
goto bail;
}
gpio->cf_copro_bankmap[bindex]--;
/* Switch command source */
if (gpio->cf_copro_bankmap[bindex] == 0)
aspeed_gpio_change_cmd_source(gpio, bank, bindex,
GPIO_CMDSRC_ARM);
bail:
raw_spin_unlock_irqrestore(&gpio->lock, flags);
return rc;
}
EXPORT_SYMBOL_GPL(aspeed_gpio_copro_release_gpio);
/*
* Any banks not specified in a struct aspeed_bank_props array are assumed to
* have the properties:
*
* { .input = 0xffffffff, .output = 0xffffffff }
*/
static const struct aspeed_bank_props ast2400_bank_props[] = {
/* input output */
{ 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
{ 6, 0x0000000f, 0x0fffff0f }, /* Y/Z/AA/AB, two 4-GPIO holes */
{ },
};
static const struct aspeed_gpio_config ast2400_config =
/* 220 for simplicity, really 216 with two 4-GPIO holes, four at end */
{ .nr_gpios = 220, .props = ast2400_bank_props, };
static const struct aspeed_bank_props ast2500_bank_props[] = {
/* input output */
{ 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
{ 6, 0x0fffffff, 0x0fffffff }, /* Y/Z/AA/AB, 4-GPIO hole */
{ 7, 0x000000ff, 0x000000ff }, /* AC */
{ },
};
static const struct aspeed_gpio_config ast2500_config =
/* 232 for simplicity, actual number is 228 (4-GPIO hole in GPIOAB) */
{ .nr_gpios = 232, .props = ast2500_bank_props, };
static const struct aspeed_bank_props ast2600_bank_props[] = {
/* input output */
{4, 0xffffffff, 0x00ffffff}, /* Q/R/S/T */
{5, 0xffffffff, 0xffffff00}, /* U/V/W/X */
{6, 0x0000ffff, 0x0000ffff}, /* Y/Z */
{ },
};
static const struct aspeed_gpio_config ast2600_config =
/*
* ast2600 has two controllers one with 208 GPIOs and one with 36 GPIOs.
* We expect ngpio being set in the device tree and this is a fallback
* option.
*/
{ .nr_gpios = 208, .props = ast2600_bank_props, };
static const struct of_device_id aspeed_gpio_of_table[] = {
{ .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, },
{ .compatible = "aspeed,ast2500-gpio", .data = &ast2500_config, },
{ .compatible = "aspeed,ast2600-gpio", .data = &ast2600_config, },
{}
};
MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table);
static int __init aspeed_gpio_probe(struct platform_device *pdev)
{
const struct of_device_id *gpio_id;
struct aspeed_gpio *gpio;
int rc, i, banks, err;
u32 ngpio;
gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
if (!gpio)
return -ENOMEM;
gpio->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(gpio->base))
return PTR_ERR(gpio->base);
raw_spin_lock_init(&gpio->lock);
gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node);
if (!gpio_id)
return -EINVAL;
gpio->clk = of_clk_get(pdev->dev.of_node, 0);
if (IS_ERR(gpio->clk)) {
dev_warn(&pdev->dev,
"Failed to get clock from devicetree, debouncing disabled\n");
gpio->clk = NULL;
}
gpio->config = gpio_id->data;
gpio->chip.parent = &pdev->dev;
err = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpio);
gpio->chip.ngpio = (u16) ngpio;
if (err)
gpio->chip.ngpio = gpio->config->nr_gpios;
gpio->chip.direction_input = aspeed_gpio_dir_in;
gpio->chip.direction_output = aspeed_gpio_dir_out;
gpio->chip.get_direction = aspeed_gpio_get_direction;
gpio->chip.request = aspeed_gpio_request;
gpio->chip.free = aspeed_gpio_free;
gpio->chip.get = aspeed_gpio_get;
gpio->chip.set = aspeed_gpio_set;
gpio->chip.set_config = aspeed_gpio_set_config;
gpio->chip.label = dev_name(&pdev->dev);
gpio->chip.base = -1;
/* Allocate a cache of the output registers */
banks = DIV_ROUND_UP(gpio->chip.ngpio, 32);
gpio->dcache = devm_kcalloc(&pdev->dev,
banks, sizeof(u32), GFP_KERNEL);
if (!gpio->dcache)
return -ENOMEM;
/*
* Populate it with initial values read from the HW and switch
* all command sources to the ARM by default
*/
for (i = 0; i < banks; i++) {
const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
void __iomem *addr = bank_reg(gpio, bank, reg_rdata);
gpio->dcache[i] = ioread32(addr);
aspeed_gpio_change_cmd_source(gpio, bank, 0, GPIO_CMDSRC_ARM);
aspeed_gpio_change_cmd_source(gpio, bank, 1, GPIO_CMDSRC_ARM);
aspeed_gpio_change_cmd_source(gpio, bank, 2, GPIO_CMDSRC_ARM);
aspeed_gpio_change_cmd_source(gpio, bank, 3, GPIO_CMDSRC_ARM);
}
/* Optionally set up an irqchip if there is an IRQ */
rc = platform_get_irq(pdev, 0);
if (rc > 0) {
struct gpio_irq_chip *girq;
gpio->irq = rc;
girq = &gpio->chip.irq;
girq->chip = &gpio->irqc;
girq->chip->name = dev_name(&pdev->dev);
girq->chip->irq_ack = aspeed_gpio_irq_ack;
girq->chip->irq_mask = aspeed_gpio_irq_mask;
girq->chip->irq_unmask = aspeed_gpio_irq_unmask;
girq->chip->irq_set_type = aspeed_gpio_set_type;
girq->parent_handler = aspeed_gpio_irq_handler;
girq->num_parents = 1;
girq->parents = devm_kcalloc(&pdev->dev, 1,
sizeof(*girq->parents),
GFP_KERNEL);
if (!girq->parents)
return -ENOMEM;
girq->parents[0] = gpio->irq;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_bad_irq;
girq->init_valid_mask = aspeed_init_irq_valid_mask;
}
gpio->offset_timer =
devm_kzalloc(&pdev->dev, gpio->chip.ngpio, GFP_KERNEL);
if (!gpio->offset_timer)
return -ENOMEM;
rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
if (rc < 0)
return rc;
return 0;
}
static struct platform_driver aspeed_gpio_driver = {
.driver = {
.name = KBUILD_MODNAME,
.of_match_table = aspeed_gpio_of_table,
},
};
module_platform_driver_probe(aspeed_gpio_driver, aspeed_gpio_probe);
MODULE_DESCRIPTION("Aspeed GPIO Driver");
MODULE_LICENSE("GPL");
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