[PATCH v4 1/7] gpio: gpio-ep93xx: fix BUG_ON port F usage

From: Nikita Shubin
Date: Fri Feb 05 2021 - 03:06:27 EST


Two index spaces and ep93xx_gpio_port conversion are confusing.

Instead add a separate struct to store necessary data and remove
ep93xx_gpio_port.

- add struct to store IRQ related data for each IRQ capable chip
- replace offset array with defined offsets
- add IRQ registers offset for each IRQ capable chip into
ep93xx_gpio_banks

------------[ cut here ]------------
kernel BUG at drivers/gpio/gpio-ep93xx.c:64!
---[ end trace 3f6544e133e9f5ae ]---

Fixes: fd935fc421e74 ("gpio: ep93xx: Do not pingpong irq numbers")
Signed-off-by: Nikita Shubin <nikita.shubin@xxxxxxxxxxx>
---
v3->v4:
- drop ep93xx_gpio_port
- embed IRQ data into struct ep93xx_gpio_irq_chip,
which also contains offset of specific IRQ
- allocate ep93xx_gpio_irq_chip for IRQ capable gpiochips
- drop offset arrays
- add IRQ register offsets defines
- add IRQ chip offset to ep93xx_gpio_banks
---
drivers/gpio/gpio-ep93xx.c | 186 ++++++++++++++++++++-----------------
1 file changed, 99 insertions(+), 87 deletions(-)

diff --git a/drivers/gpio/gpio-ep93xx.c b/drivers/gpio/gpio-ep93xx.c
index 226da8df6f10..e3b5e2c37259 100644
--- a/drivers/gpio/gpio-ep93xx.c
+++ b/drivers/gpio/gpio-ep93xx.c
@@ -25,6 +25,9 @@
/* Maximum value for gpio line identifiers */
#define EP93XX_GPIO_LINE_MAX 63

+/* Number of GPIO chips in EP93XX */
+#define EP93XX_GPIO_CHIP_NUM 8
+
/* Maximum value for irq capable line identifiers */
#define EP93XX_GPIO_LINE_MAX_IRQ 23

@@ -34,74 +37,74 @@
*/
#define EP93XX_GPIO_F_IRQ_BASE 80

-struct ep93xx_gpio {
- void __iomem *base;
- struct gpio_chip gc[8];
+struct ep93xx_gpio_irq_chip {
+ u8 irq_offset;
+ u8 int_unmasked;
+ u8 int_enabled;
+ u8 int_type1;
+ u8 int_type2;
+ u8 int_debounce;
};

-/*************************************************************************
- * Interrupt handling for EP93xx on-chip GPIOs
- *************************************************************************/
-static unsigned char gpio_int_unmasked[3];
-static unsigned char gpio_int_enabled[3];
-static unsigned char gpio_int_type1[3];
-static unsigned char gpio_int_type2[3];
-static unsigned char gpio_int_debounce[3];
-
-/* Port ordering is: A B F */
-static const u8 int_type1_register_offset[3] = { 0x90, 0xac, 0x4c };
-static const u8 int_type2_register_offset[3] = { 0x94, 0xb0, 0x50 };
-static const u8 eoi_register_offset[3] = { 0x98, 0xb4, 0x54 };
-static const u8 int_en_register_offset[3] = { 0x9c, 0xb8, 0x58 };
-static const u8 int_debounce_register_offset[3] = { 0xa8, 0xc4, 0x64 };
-
-static void ep93xx_gpio_update_int_params(struct ep93xx_gpio *epg, unsigned port)
-{
- BUG_ON(port > 2);
+struct ep93xx_gpio_chip {
+ struct gpio_chip gc;
+ struct ep93xx_gpio_irq_chip *eic;
+};

- writeb_relaxed(0, epg->base + int_en_register_offset[port]);
+struct ep93xx_gpio {
+ void __iomem *base;
+ struct ep93xx_gpio_chip gc[EP93XX_GPIO_CHIP_NUM];
+};

- writeb_relaxed(gpio_int_type2[port],
- epg->base + int_type2_register_offset[port]);
+#define to_ep93xx_gpio_chip(x) container_of(x, struct ep93xx_gpio_chip, gc)

- writeb_relaxed(gpio_int_type1[port],
- epg->base + int_type1_register_offset[port]);
+struct ep93xx_gpio_irq_chip *to_ep93xx_gpio_irq_chip(struct gpio_chip *gc)
+{
+ struct ep93xx_gpio_chip *egc = to_ep93xx_gpio_chip(gc);

- writeb(gpio_int_unmasked[port] & gpio_int_enabled[port],
- epg->base + int_en_register_offset[port]);
+ return egc->eic;
}

-static int ep93xx_gpio_port(struct gpio_chip *gc)
+/*************************************************************************
+ * Interrupt handling for EP93xx on-chip GPIOs
+ *************************************************************************/
+#define EP93XX_INT_TYPE1_OFFSET 0x00
+#define EP93XX_INT_TYPE2_OFFSET 0x04
+#define EP93XX_INT_EOI_OFFSET 0x08
+#define EP93XX_INT_EN_OFFSET 0x0c
+#define EP93XX_INT_STATUS_OFFSET 0x10
+#define EP93XX_INT_RAW_STATUS_OFFSET 0x14
+#define EP93XX_INT_DEBOUNCE_OFFSET 0x18
+
+static void ep93xx_gpio_update_int_params(struct ep93xx_gpio *epg,
+ struct ep93xx_gpio_irq_chip *eic)
{
- struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = 0;
+ writeb_relaxed(0, epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET);

- while (port < ARRAY_SIZE(epg->gc) && gc != &epg->gc[port])
- port++;
+ writeb_relaxed(eic->int_type2,
+ epg->base + eic->irq_offset + EP93XX_INT_TYPE2_OFFSET);

- /* This should not happen but is there as a last safeguard */
- if (port == ARRAY_SIZE(epg->gc)) {
- pr_crit("can't find the GPIO port\n");
- return 0;
- }
+ writeb_relaxed(eic->int_type1,
+ epg->base + eic->irq_offset + EP93XX_INT_TYPE1_OFFSET);

- return port;
+ writeb_relaxed(eic->int_unmasked & eic->int_enabled,
+ epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET);
}

static void ep93xx_gpio_int_debounce(struct gpio_chip *gc,
unsigned int offset, bool enable)
{
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = ep93xx_gpio_port(gc);
+ struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
int port_mask = BIT(offset);

if (enable)
- gpio_int_debounce[port] |= port_mask;
+ eic->int_debounce |= port_mask;
else
- gpio_int_debounce[port] &= ~port_mask;
+ eic->int_debounce &= ~port_mask;

- writeb(gpio_int_debounce[port],
- epg->base + int_debounce_register_offset[port]);
+ writeb(eic->int_debounce,
+ epg->base + eic->irq_offset + EP93XX_INT_DEBOUNCE_OFFSET);
}

static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc)
@@ -122,12 +125,12 @@ static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc)
*/
stat = readb(epg->base + EP93XX_GPIO_A_INT_STATUS);
for_each_set_bit(offset, &stat, 8)
- generic_handle_irq(irq_find_mapping(epg->gc[0].irq.domain,
+ generic_handle_irq(irq_find_mapping(epg->gc[0].gc.irq.domain,
offset));

stat = readb(epg->base + EP93XX_GPIO_B_INT_STATUS);
for_each_set_bit(offset, &stat, 8)
- generic_handle_irq(irq_find_mapping(epg->gc[1].irq.domain,
+ generic_handle_irq(irq_find_mapping(epg->gc[1].gc.irq.domain,
offset));

chained_irq_exit(irqchip, desc);
@@ -153,52 +156,52 @@ static void ep93xx_gpio_f_irq_handler(struct irq_desc *desc)
static void ep93xx_gpio_irq_ack(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = ep93xx_gpio_port(gc);
int port_mask = BIT(d->irq & 7);

if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) {
- gpio_int_type2[port] ^= port_mask; /* switch edge direction */
- ep93xx_gpio_update_int_params(epg, port);
+ eic->int_type2 ^= port_mask; /* switch edge direction */
+ ep93xx_gpio_update_int_params(epg, eic);
}

- writeb(port_mask, epg->base + eoi_register_offset[port]);
+ writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
}

static void ep93xx_gpio_irq_mask_ack(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = ep93xx_gpio_port(gc);
int port_mask = BIT(d->irq & 7);

if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH)
- gpio_int_type2[port] ^= port_mask; /* switch edge direction */
+ eic->int_type2 ^= port_mask; /* switch edge direction */

- gpio_int_unmasked[port] &= ~port_mask;
- ep93xx_gpio_update_int_params(epg, port);
+ eic->int_unmasked &= ~port_mask;
+ ep93xx_gpio_update_int_params(epg, eic);

- writeb(port_mask, epg->base + eoi_register_offset[port]);
+ writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
}

static void ep93xx_gpio_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = ep93xx_gpio_port(gc);

- gpio_int_unmasked[port] &= ~BIT(d->irq & 7);
- ep93xx_gpio_update_int_params(epg, port);
+ eic->int_unmasked &= ~BIT(d->irq & 7);
+ ep93xx_gpio_update_int_params(epg, eic);
}

static void ep93xx_gpio_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = ep93xx_gpio_port(gc);

- gpio_int_unmasked[port] |= BIT(d->irq & 7);
- ep93xx_gpio_update_int_params(epg, port);
+ eic->int_unmasked |= BIT(d->irq & 7);
+ ep93xx_gpio_update_int_params(epg, eic);
}

/*
@@ -209,8 +212,8 @@ static void ep93xx_gpio_irq_unmask(struct irq_data *d)
static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
- int port = ep93xx_gpio_port(gc);
int offset = d->irq & 7;
int port_mask = BIT(offset);
irq_flow_handler_t handler;
@@ -219,32 +222,32 @@ static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type)

switch (type) {
case IRQ_TYPE_EDGE_RISING:
- gpio_int_type1[port] |= port_mask;
- gpio_int_type2[port] |= port_mask;
+ eic->int_type1 |= port_mask;
+ eic->int_type2 |= port_mask;
handler = handle_edge_irq;
break;
case IRQ_TYPE_EDGE_FALLING:
- gpio_int_type1[port] |= port_mask;
- gpio_int_type2[port] &= ~port_mask;
+ eic->int_type1 |= port_mask;
+ eic->int_type2 &= ~port_mask;
handler = handle_edge_irq;
break;
case IRQ_TYPE_LEVEL_HIGH:
- gpio_int_type1[port] &= ~port_mask;
- gpio_int_type2[port] |= port_mask;
+ eic->int_type1 &= ~port_mask;
+ eic->int_type2 |= port_mask;
handler = handle_level_irq;
break;
case IRQ_TYPE_LEVEL_LOW:
- gpio_int_type1[port] &= ~port_mask;
- gpio_int_type2[port] &= ~port_mask;
+ eic->int_type1 &= ~port_mask;
+ eic->int_type2 &= ~port_mask;
handler = handle_level_irq;
break;
case IRQ_TYPE_EDGE_BOTH:
- gpio_int_type1[port] |= port_mask;
+ eic->int_type1 |= port_mask;
/* set initial polarity based on current input level */
if (gc->get(gc, offset))
- gpio_int_type2[port] &= ~port_mask; /* falling */
+ eic->int_type2 &= ~port_mask; /* falling */
else
- gpio_int_type2[port] |= port_mask; /* rising */
+ eic->int_type2 |= port_mask; /* rising */
handler = handle_edge_irq;
break;
default:
@@ -253,9 +256,9 @@ static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type)

irq_set_handler_locked(d, handler);

- gpio_int_enabled[port] |= port_mask;
+ eic->int_enabled |= port_mask;

- ep93xx_gpio_update_int_params(epg, port);
+ ep93xx_gpio_update_int_params(epg, eic);

return 0;
}
@@ -276,17 +279,19 @@ struct ep93xx_gpio_bank {
const char *label;
int data;
int dir;
+ int irq;
int base;
bool has_irq;
bool has_hierarchical_irq;
unsigned int irq_base;
};

-#define EP93XX_GPIO_BANK(_label, _data, _dir, _base, _has_irq, _has_hier, _irq_base) \
+#define EP93XX_GPIO_BANK(_label, _data, _dir, _irq, _base, _has_irq, _has_hier, _irq_base) \
{ \
.label = _label, \
.data = _data, \
.dir = _dir, \
+ .irq = _irq, \
.base = _base, \
.has_irq = _has_irq, \
.has_hierarchical_irq = _has_hier, \
@@ -295,16 +300,16 @@ struct ep93xx_gpio_bank {

static struct ep93xx_gpio_bank ep93xx_gpio_banks[] = {
/* Bank A has 8 IRQs */
- EP93XX_GPIO_BANK("A", 0x00, 0x10, 0, true, false, 64),
+ EP93XX_GPIO_BANK("A", 0x00, 0x10, 0x90, 0, true, false, 64),
/* Bank B has 8 IRQs */
- EP93XX_GPIO_BANK("B", 0x04, 0x14, 8, true, false, 72),
- EP93XX_GPIO_BANK("C", 0x08, 0x18, 40, false, false, 0),
- EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24, false, false, 0),
- EP93XX_GPIO_BANK("E", 0x20, 0x24, 32, false, false, 0),
+ EP93XX_GPIO_BANK("B", 0x04, 0x14, 0xac, 8, true, false, 72),
+ EP93XX_GPIO_BANK("C", 0x08, 0x18, 0x00, 40, false, false, 0),
+ EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 0x00, 24, false, false, 0),
+ EP93XX_GPIO_BANK("E", 0x20, 0x24, 0x00, 32, false, false, 0),
/* Bank F has 8 IRQs */
- EP93XX_GPIO_BANK("F", 0x30, 0x34, 16, false, true, 0),
- EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48, false, false, 0),
- EP93XX_GPIO_BANK("H", 0x40, 0x44, 56, false, false, 0),
+ EP93XX_GPIO_BANK("F", 0x30, 0x34, 0x4c, 16, false, true, 0),
+ EP93XX_GPIO_BANK("G", 0x38, 0x3c, 0x00, 48, false, false, 0),
+ EP93XX_GPIO_BANK("H", 0x40, 0x44, 0x00, 56, false, false, 0),
};

static int ep93xx_gpio_set_config(struct gpio_chip *gc, unsigned offset,
@@ -326,13 +331,14 @@ static int ep93xx_gpio_f_to_irq(struct gpio_chip *gc, unsigned offset)
return EP93XX_GPIO_F_IRQ_BASE + offset;
}

-static int ep93xx_gpio_add_bank(struct gpio_chip *gc,
+static int ep93xx_gpio_add_bank(struct ep93xx_gpio_chip *egc,
struct platform_device *pdev,
struct ep93xx_gpio *epg,
struct ep93xx_gpio_bank *bank)
{
void __iomem *data = epg->base + bank->data;
void __iomem *dir = epg->base + bank->dir;
+ struct gpio_chip *gc = &egc->gc;
struct device *dev = &pdev->dev;
struct gpio_irq_chip *girq;
int err;
@@ -347,6 +353,12 @@ static int ep93xx_gpio_add_bank(struct gpio_chip *gc,
girq = &gc->irq;
if (bank->has_irq || bank->has_hierarchical_irq) {
gc->set_config = ep93xx_gpio_set_config;
+ egc->eic = devm_kcalloc(dev, 1,
+ sizeof(*egc->eic),
+ GFP_KERNEL);
+ if (!egc->eic)
+ return -ENOMEM;
+ egc->eic->irq_offset = bank->irq;
girq->chip = &ep93xx_gpio_irq_chip;
}

@@ -415,7 +427,7 @@ static int ep93xx_gpio_probe(struct platform_device *pdev)
return PTR_ERR(epg->base);

for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
- struct gpio_chip *gc = &epg->gc[i];
+ struct ep93xx_gpio_chip *gc = &epg->gc[i];
struct ep93xx_gpio_bank *bank = &ep93xx_gpio_banks[i];

if (ep93xx_gpio_add_bank(gc, pdev, epg, bank))
--
2.26.2