[PATCH v8 10/18] gpio: pl061: convert register access to regmap
From: Long Zhao via B4 Relay
Date: Mon Sep 21 2026 - 00:28:30 EST
From: Long Zhao <longzhao@xxxxxxxxxxxxx>
Replace readb()/writeb() with a MMIO regmap while keeping the existing
gpio_chip and girq irqchip. Use a raw spinlock so irq_ack() can run
under the irq descriptor lock.
Signed-off-by: Long Zhao <longzhao@xxxxxxxxxxxxx>
---
drivers/gpio/Kconfig | 1 +
drivers/gpio/gpio-pl061.c | 134 ++++++++++++++++++++++++++++++----------------
2 files changed, 89 insertions(+), 46 deletions(-)
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index f03c05288376..2a1487bd1a94 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -583,6 +583,7 @@ config GPIO_PL061
depends on ARM_AMBA || COMPILE_TEST
select IRQ_DOMAIN
select GPIOLIB_IRQCHIP
+ select REGMAP_MMIO
help
Say yes here to support the PrimeCell PL061 GPIO device.
diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
index 919cf86fd590..66aea0856bc4 100644
--- a/drivers/gpio/gpio-pl061.c
+++ b/drivers/gpio/gpio-pl061.c
@@ -19,9 +19,11 @@
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
+#include <linux/log2.h>
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm.h>
+#include <linux/regmap.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
@@ -36,6 +38,7 @@
#define GPIOIC 0x41C
#define PL061_GPIO_NR 8
+#define PL061_DATA_OFFSET 2
struct pl061_context_save_regs {
u8 gpio_data;
@@ -49,18 +52,49 @@ struct pl061_context_save_regs {
struct pl061 {
raw_spinlock_t lock;
- void __iomem *base;
+ struct regmap *regmap;
struct gpio_chip gc;
int parent_irq;
struct pl061_context_save_regs csave_regs;
};
+static bool pl061_is_data_reg(unsigned int reg)
+{
+ return is_power_of_2(reg) &&
+ reg >= BIT(PL061_DATA_OFFSET) &&
+ reg <= BIT(PL061_DATA_OFFSET + PL061_GPIO_NR - 1);
+}
+
+static bool pl061_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case GPIOMIS:
+ case GPIOIC:
+ return true;
+ default:
+ return pl061_is_data_reg(reg);
+ }
+}
+
+static const struct regmap_config pl061_regmap_config = {
+ .reg_bits = 16,
+ .val_bits = 8,
+ .reg_stride = 4,
+ .max_register = GPIOIC,
+ .volatile_reg = pl061_volatile_reg,
+ .fast_io = true,
+ .use_raw_spinlock = true,
+};
+
static int pl061_get_direction(struct gpio_chip *gc, unsigned offset)
{
struct pl061 *pl061 = gpiochip_get_data(gc);
+ unsigned int gpiodir = 0;
- if (readb(pl061->base + GPIODIR) & BIT(offset))
+ regmap_read(pl061->regmap, GPIODIR, &gpiodir);
+
+ if (gpiodir & BIT(offset))
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
@@ -70,12 +104,9 @@ static int pl061_direction_input(struct gpio_chip *gc, unsigned offset)
{
struct pl061 *pl061 = gpiochip_get_data(gc);
unsigned long flags;
- unsigned char gpiodir;
raw_spin_lock_irqsave(&pl061->lock, flags);
- gpiodir = readb(pl061->base + GPIODIR);
- gpiodir &= ~(BIT(offset));
- writeb(gpiodir, pl061->base + GPIODIR);
+ regmap_update_bits(pl061->regmap, GPIODIR, BIT(offset), 0);
raw_spin_unlock_irqrestore(&pl061->lock, flags);
return 0;
@@ -86,19 +117,19 @@ static int pl061_direction_output(struct gpio_chip *gc, unsigned offset,
{
struct pl061 *pl061 = gpiochip_get_data(gc);
unsigned long flags;
- unsigned char gpiodir;
+ unsigned int mask = BIT(offset);
raw_spin_lock_irqsave(&pl061->lock, flags);
- writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
- gpiodir = readb(pl061->base + GPIODIR);
- gpiodir |= BIT(offset);
- writeb(gpiodir, pl061->base + GPIODIR);
+ regmap_write(pl061->regmap, BIT(offset + PL061_DATA_OFFSET),
+ !!value << offset);
+ regmap_update_bits(pl061->regmap, GPIODIR, mask, mask);
/*
* gpio value is set again, because pl061 doesn't allow to set value of
* a gpio pin before configuring it in OUT mode.
*/
- writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
+ regmap_write(pl061->regmap, BIT(offset + PL061_DATA_OFFSET),
+ !!value << offset);
raw_spin_unlock_irqrestore(&pl061->lock, flags);
return 0;
@@ -107,15 +138,19 @@ static int pl061_direction_output(struct gpio_chip *gc, unsigned offset,
static int pl061_get_value(struct gpio_chip *gc, unsigned offset)
{
struct pl061 *pl061 = gpiochip_get_data(gc);
+ unsigned int val = 0;
+
+ regmap_read(pl061->regmap, BIT(offset + PL061_DATA_OFFSET), &val);
- return !!readb(pl061->base + (BIT(offset + 2)));
+ return !!val;
}
static int pl061_set_value(struct gpio_chip *gc, unsigned int offset, int value)
{
struct pl061 *pl061 = gpiochip_get_data(gc);
- writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
+ regmap_write(pl061->regmap, BIT(offset + PL061_DATA_OFFSET),
+ !!value << offset);
return 0;
}
@@ -126,8 +161,8 @@ static int pl061_irq_type(struct irq_data *d, unsigned trigger)
struct pl061 *pl061 = gpiochip_get_data(gc);
int offset = irqd_to_hwirq(d);
unsigned long flags;
- u8 gpiois, gpioibe, gpioiev;
- u8 bit = BIT(offset);
+ unsigned int gpiois = 0, gpioibe = 0, gpioiev = 0;
+ unsigned int bit = BIT(offset);
if (offset < 0 || offset >= PL061_GPIO_NR)
return -EINVAL;
@@ -145,9 +180,9 @@ static int pl061_irq_type(struct irq_data *d, unsigned trigger)
raw_spin_lock_irqsave(&pl061->lock, flags);
- gpioiev = readb(pl061->base + GPIOIEV);
- gpiois = readb(pl061->base + GPIOIS);
- gpioibe = readb(pl061->base + GPIOIBE);
+ regmap_read(pl061->regmap, GPIOIEV, &gpioiev);
+ regmap_read(pl061->regmap, GPIOIS, &gpiois);
+ regmap_read(pl061->regmap, GPIOIBE, &gpioibe);
if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
bool polarity = trigger & IRQ_TYPE_LEVEL_HIGH;
@@ -199,9 +234,9 @@ static int pl061_irq_type(struct irq_data *d, unsigned trigger)
offset);
}
- writeb(gpiois, pl061->base + GPIOIS);
- writeb(gpioibe, pl061->base + GPIOIBE);
- writeb(gpioiev, pl061->base + GPIOIEV);
+ regmap_write(pl061->regmap, GPIOIS, gpiois);
+ regmap_write(pl061->regmap, GPIOIBE, gpioibe);
+ regmap_write(pl061->regmap, GPIOIEV, gpioiev);
raw_spin_unlock_irqrestore(&pl061->lock, flags);
@@ -211,6 +246,7 @@ static int pl061_irq_type(struct irq_data *d, unsigned trigger)
static void pl061_irq_handler(struct irq_desc *desc)
{
unsigned long pending;
+ unsigned int mis = 0;
int offset;
struct gpio_chip *gc = irq_desc_get_handler_data(desc);
struct pl061 *pl061 = gpiochip_get_data(gc);
@@ -218,8 +254,9 @@ static void pl061_irq_handler(struct irq_desc *desc)
chained_irq_enter(irqchip, desc);
- pending = readb(pl061->base + GPIOMIS);
- if (pending) {
+ regmap_read(pl061->regmap, GPIOMIS, &mis);
+ if (mis) {
+ pending = mis;
for_each_set_bit(offset, &pending, PL061_GPIO_NR)
generic_handle_domain_irq(gc->irq.domain,
offset);
@@ -233,11 +270,9 @@ static void pl061_irq_mask(struct irq_data *d)
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pl061 *pl061 = gpiochip_get_data(gc);
u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
- u8 gpioie;
raw_spin_lock(&pl061->lock);
- gpioie = readb(pl061->base + GPIOIE) & ~mask;
- writeb(gpioie, pl061->base + GPIOIE);
+ regmap_update_bits(pl061->regmap, GPIOIE, mask, 0);
raw_spin_unlock(&pl061->lock);
gpiochip_disable_irq(gc, d->hwirq);
@@ -248,13 +283,11 @@ static void pl061_irq_unmask(struct irq_data *d)
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pl061 *pl061 = gpiochip_get_data(gc);
u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
- u8 gpioie;
gpiochip_enable_irq(gc, d->hwirq);
raw_spin_lock(&pl061->lock);
- gpioie = readb(pl061->base + GPIOIE) | mask;
- writeb(gpioie, pl061->base + GPIOIE);
+ regmap_update_bits(pl061->regmap, GPIOIE, mask, mask);
raw_spin_unlock(&pl061->lock);
}
@@ -272,9 +305,7 @@ static void pl061_irq_ack(struct irq_data *d)
struct pl061 *pl061 = gpiochip_get_data(gc);
u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
- raw_spin_lock(&pl061->lock);
- writeb(mask, pl061->base + GPIOIC);
- raw_spin_unlock(&pl061->lock);
+ regmap_write(pl061->regmap, GPIOIC, mask);
}
static int pl061_irq_set_wake(struct irq_data *d, unsigned int state)
@@ -308,15 +339,20 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
struct device *dev = &adev->dev;
struct pl061 *pl061;
struct gpio_irq_chip *girq;
+ void __iomem *base;
int ret, irq;
pl061 = devm_kzalloc(dev, sizeof(*pl061), GFP_KERNEL);
if (pl061 == NULL)
return -ENOMEM;
- pl061->base = devm_ioremap_resource(dev, &adev->res);
- if (IS_ERR(pl061->base))
- return PTR_ERR(pl061->base);
+ base = devm_ioremap_resource(dev, &adev->res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ pl061->regmap = devm_regmap_init_mmio(dev, base, &pl061_regmap_config);
+ if (IS_ERR(pl061->regmap))
+ return PTR_ERR(pl061->regmap);
raw_spin_lock_init(&pl061->lock);
pl061->gc.request = gpiochip_generic_request;
@@ -335,7 +371,7 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
/*
* irq_chip support
*/
- writeb(0, pl061->base + GPIOIE); /* disable irqs */
+ regmap_write(pl061->regmap, GPIOIE, 0); /* disable irqs */
irq = adev->irq[0];
if (!irq)
dev_warn(&adev->dev, "IRQ support disabled\n");
@@ -366,14 +402,20 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
static int pl061_suspend(struct device *dev)
{
struct pl061 *pl061 = dev_get_drvdata(dev);
+ unsigned int val = 0;
int offset;
pl061->csave_regs.gpio_data = 0;
- pl061->csave_regs.gpio_dir = readb(pl061->base + GPIODIR);
- pl061->csave_regs.gpio_is = readb(pl061->base + GPIOIS);
- pl061->csave_regs.gpio_ibe = readb(pl061->base + GPIOIBE);
- pl061->csave_regs.gpio_iev = readb(pl061->base + GPIOIEV);
- pl061->csave_regs.gpio_ie = readb(pl061->base + GPIOIE);
+ regmap_read(pl061->regmap, GPIODIR, &val);
+ pl061->csave_regs.gpio_dir = val;
+ regmap_read(pl061->regmap, GPIOIS, &val);
+ pl061->csave_regs.gpio_is = val;
+ regmap_read(pl061->regmap, GPIOIBE, &val);
+ pl061->csave_regs.gpio_ibe = val;
+ regmap_read(pl061->regmap, GPIOIEV, &val);
+ pl061->csave_regs.gpio_iev = val;
+ regmap_read(pl061->regmap, GPIOIE, &val);
+ pl061->csave_regs.gpio_ie = val;
for (offset = 0; offset < PL061_GPIO_NR; offset++) {
if (pl061->csave_regs.gpio_dir & (BIT(offset)))
@@ -398,10 +440,10 @@ static int pl061_resume(struct device *dev)
pl061_direction_input(&pl061->gc, offset);
}
- writeb(pl061->csave_regs.gpio_is, pl061->base + GPIOIS);
- writeb(pl061->csave_regs.gpio_ibe, pl061->base + GPIOIBE);
- writeb(pl061->csave_regs.gpio_iev, pl061->base + GPIOIEV);
- writeb(pl061->csave_regs.gpio_ie, pl061->base + GPIOIE);
+ regmap_write(pl061->regmap, GPIOIS, pl061->csave_regs.gpio_is);
+ regmap_write(pl061->regmap, GPIOIBE, pl061->csave_regs.gpio_ibe);
+ regmap_write(pl061->regmap, GPIOIEV, pl061->csave_regs.gpio_iev);
+ regmap_write(pl061->regmap, GPIOIE, pl061->csave_regs.gpio_ie);
return 0;
}
--
2.34.1