static int byt_gpio_direction_output(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct byt_gpio *vg = to_byt_gpio(chip);
void __iomem *conf_reg = byt_gpio_reg(chip, gpio, BYT_CONF0_REG);
void __iomem *reg = byt_gpio_reg(chip, gpio, BYT_VAL_REG);
unsigned long flags;
u32 reg_val;
spin_lock_irqsave(&vg->lock, flags);
/*
* Before making any direction modifications, do a check if gpio
* is set for direct IRQ. On baytrail, setting GPIO to output does
* not make sense, so let's at least warn the caller before they shoot
* themselves in the foot.
*/
WARN(readl(conf_reg) & BYT_DIRECT_IRQ_EN,
"Potential Error: Setting GPIO with direct_irq_en to output");
reg_val = readl(reg) | BYT_DIR_MASK;
reg_val &= ~BYT_OUTPUT_EN;
if (value)
writel(reg_val | BYT_LEVEL, reg);
else
writel(reg_val & ~BYT_LEVEL, reg);
spin_unlock_irqrestore(&vg->lock, flags);
return 0;
}
static int byt_gpio_request(struct gpio_chip *chip, unsigned offset)
{
struct byt_gpio *vg = to_byt_gpio(chip);
void __iomem *reg = byt_gpio_reg(chip, offset, BYT_CONF0_REG);
u32 value;
bool special;
/*
* In most cases, func pin mux 000 means GPIO function.
* But, some pins may have func pin mux 001 represents
* GPIO function. Only allow user to export pin with
* func pin mux preset as GPIO function by BIOS/FW.
*/
value = readl(reg) & BYT_PIN_MUX;
special = is_special_pin(vg, offset);
if ((special && value != 1) || (!special && value)) {
dev_err(&vg->pdev->dev,
"pin %u cannot be used as GPIO.\n", offset);
return -EINVAL;
}
pm_runtime_get(&vg->pdev->dev);
return 0;
}
static void byt_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct irq_data *data = irq_desc_get_irq_data(desc);
struct byt_gpio *vg = to_byt_gpio(irq_desc_get_handler_data(desc));
struct irq_chip *chip = irq_data_get_irq_chip(data);
u32 base, pin, mask;
void __iomem *reg;
u32 pending;
unsigned virq;
int looplimit = 0;
/* check from GPIO controller which pin triggered the interrupt */
for (base = 0; base < vg->chip.ngpio; base += 32) {
reg = byt_gpio_reg(&vg->chip, base, BYT_INT_STAT_REG);
while ((pending = readl(reg))) {
pin = __ffs(pending);
mask = BIT(pin);
/* Clear before handling so we can't lose an edge */
writel(mask, reg);
virq = irq_find_mapping(vg->chip.irqdomain, base + pin);
generic_handle_irq(virq);
/* In case bios or user sets triggering incorretly a pin
* might remain in "interrupt triggered" state.
*/
if (looplimit++ > 32) {
dev_err(&vg->pdev->dev,
"Gpio %d interrupt flood, disabling\n",
base + pin);
reg = byt_gpio_reg(&vg->chip, base + pin,
BYT_CONF0_REG);
mask = readl(reg);
mask &= ~(BYT_TRIG_NEG | BYT_TRIG_POS |
BYT_TRIG_LVL);
writel(mask, reg);
mask = readl(reg); /* flush */
break;
}
}
}
chip->irq_eoi(data);
}
static void byt_gpio_free(struct gpio_chip *chip, unsigned offset)
{
struct byt_gpio *vg = to_byt_gpio(chip);
void __iomem *reg = byt_gpio_reg(&vg->chip, offset, BYT_CONF0_REG);
u32 value;
/* clear interrupt triggering */
value = readl(reg);
value &= ~(BYT_TRIG_POS | BYT_TRIG_NEG | BYT_TRIG_LVL);
writel(value, reg);
pm_runtime_put(&vg->pdev->dev);
}
static void byt_gpio_irq_init_hw(struct byt_gpio *vg)
{
void __iomem *reg;
u32 base, value;
/* clear interrupt status trigger registers */
for (base = 0; base < vg->chip.ngpio; base += 32) {
reg = byt_gpio_reg(&vg->chip, base, BYT_INT_STAT_REG);
writel(0xffffffff, reg);
/* make sure trigger bits are cleared, if not then a pin
might be misconfigured in bios */
value = readl(reg);
if (value)
dev_err(&vg->pdev->dev,
"GPIO interrupt error, pins misconfigured\n");
}
}
static int byt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct byt_gpio *vg = to_byt_gpio(chip);
void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
unsigned long flags;
u32 value;
spin_lock_irqsave(&vg->lock, flags);
value = readl(reg) | BYT_DIR_MASK;
value &= ~BYT_INPUT_EN; /* active low */
writel(value, reg);
spin_unlock_irqrestore(&vg->lock, flags);
return 0;
}
static void byt_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct byt_gpio *vg = to_byt_gpio(chip);
void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
unsigned long flags;
u32 old_val;
spin_lock_irqsave(&vg->lock, flags);
old_val = readl(reg);
if (value)
writel(old_val | BYT_LEVEL, reg);
else
writel(old_val & ~BYT_LEVEL, reg);
spin_unlock_irqrestore(&vg->lock, flags);
}
static int byt_irq_type(struct irq_data *d, unsigned type)
{
struct byt_gpio *vg = to_byt_gpio(irq_data_get_irq_chip_data(d));
u32 offset = irqd_to_hwirq(d);
u32 value;
unsigned long flags;
void __iomem *reg = byt_gpio_reg(&vg->chip, offset, BYT_CONF0_REG);
if (offset >= vg->chip.ngpio)
return -EINVAL;
spin_lock_irqsave(&vg->lock, flags);
value = readl(reg);
/* For level trigges the BYT_TRIG_POS and BYT_TRIG_NEG bits
* are used to indicate high and low level triggering
*/
value &= ~(BYT_TRIG_POS | BYT_TRIG_NEG | BYT_TRIG_LVL);
switch (type) {
case IRQ_TYPE_LEVEL_HIGH:
value |= BYT_TRIG_LVL;
case IRQ_TYPE_EDGE_RISING:
value |= BYT_TRIG_POS;
break;
case IRQ_TYPE_LEVEL_LOW:
value |= BYT_TRIG_LVL;
case IRQ_TYPE_EDGE_FALLING:
value |= BYT_TRIG_NEG;
break;
case IRQ_TYPE_EDGE_BOTH:
value |= (BYT_TRIG_NEG | BYT_TRIG_POS);
break;
}
writel(value, reg);
spin_unlock_irqrestore(&vg->lock, flags);
return 0;
}
static int byt_gpio_direction_output(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct byt_gpio *vg = to_byt_gpio(chip);
void __iomem *reg = byt_gpio_reg(chip, gpio, BYT_VAL_REG);
unsigned long flags;
u32 reg_val;
spin_lock_irqsave(&vg->lock, flags);
reg_val = readl(reg) | BYT_DIR_MASK;
reg_val &= ~(BYT_OUTPUT_EN | BYT_INPUT_EN);
if (value)
writel(reg_val | BYT_LEVEL, reg);
else
writel(reg_val & ~BYT_LEVEL, reg);
spin_unlock_irqrestore(&vg->lock, flags);
return 0;
}
static int byt_gpio_get(struct gpio_chip *chip, unsigned offset)
{
void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
return readl(reg) & BYT_LEVEL;
}