[linux-yocto] [PATCH 3/5] gpio-pca953x: add PCAL9535 interrupt support
Yong Li
sdliyong at gmail.com
Thu Mar 31 00:33:07 PDT 2016
Galileo gen 2 board uses the PCAL9535 as the GPIO expansion,
it is different from PCA9535 and includes interrupt mask/status registers,
The current driver does not support the interrupt registers configuration,
it causes some gpio pins cannot trigger interrupt events,
this patch fix this issue. The original patch was submitted by
Josef Ahmad <josef.ahmad at linux.intel.com>
http://git.yoctoproject.org/cgit/cgit.cgi/meta-intel-quark/tree/recipes-kernel/linux/files/0015-Quark-GPIO-1-2-quark.patch
Upstream-Status: submission pending
Signed-off-by: Yong Li <sdliyong at gmail.com>
---
drivers/gpio/gpio-pca953x.c | 103 ++++++++++++++++++++++++++++++++++----------
1 file changed, 81 insertions(+), 22 deletions(-)
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 2d4892c..31b09a2 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -18,6 +18,7 @@
#include <linux/i2c.h>
#include <linux/platform_data/pca953x.h>
#include <linux/slab.h>
+#include <asm/unaligned.h>
#ifdef CONFIG_OF_GPIO
#include <linux/of_platform.h>
#endif
@@ -39,10 +40,16 @@
#define PCA957X_MSK 6
#define PCA957X_INTS 7
+#define PCAL953X_IN_LATCH 34
+#define PCAL953X_INT_MASK 37
+#define PCAL953X_INT_STAT 38
+
#define PCA_GPIO_MASK 0x00FF
#define PCA_INT 0x0100
#define PCA953X_TYPE 0x1000
#define PCA957X_TYPE 0x2000
+#define PCAL953X_TYPE 0x4000
+
#define PCA_TYPE_MASK 0xF000
#define PCA_CHIP_TYPE(x) ((x) & PCA_TYPE_MASK)
@@ -51,6 +58,7 @@ static const struct i2c_device_id pca953x_id[] = {
{ "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
{ "pca9534", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
+ { "pcal9535", 16 | PCAL953X_TYPE | PCA_INT, },
{ "pca9536", 4 | PCA953X_TYPE, },
{ "pca9537", 4 | PCA953X_TYPE | PCA_INT, },
{ "pca9538", 8 | PCA953X_TYPE | PCA_INT, },
@@ -78,7 +86,7 @@ static const struct i2c_device_id pca953x_id[] = {
MODULE_DEVICE_TABLE(i2c, pca953x_id);
static const struct acpi_device_id pca953x_acpi_ids[] = {
- { "INT3491", 16 | PCA953X_TYPE | PCA_INT, },
+ { "INT3491", 16 | PCAL953X_TYPE | PCA_INT, },
{ }
};
MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
@@ -165,8 +173,9 @@ static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
} else {
switch (chip->chip_type) {
case PCA953X_TYPE:
+ case PCAL953X_TYPE:
ret = i2c_smbus_write_word_data(chip->client,
- reg << 1, (u16) *val);
+ reg << 1, cpu_to_le16(get_unaligned((u16 *) val)));
break;
case PCA957X_TYPE:
ret = i2c_smbus_write_byte_data(chip->client, reg << 1,
@@ -225,6 +234,7 @@ static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
switch (chip->chip_type) {
case PCA953X_TYPE:
+ case PCAL953X_TYPE:
offset = PCA953X_DIRECTION;
break;
case PCA957X_TYPE:
@@ -260,6 +270,7 @@ static int pca953x_gpio_direction_output(struct gpio_chip *gc,
switch (chip->chip_type) {
case PCA953X_TYPE:
+ case PCAL953X_TYPE:
offset = PCA953X_OUTPUT;
break;
case PCA957X_TYPE:
@@ -276,6 +287,7 @@ static int pca953x_gpio_direction_output(struct gpio_chip *gc,
reg_val = chip->reg_direction[off / BANK_SZ] & ~(1u << (off % BANK_SZ));
switch (chip->chip_type) {
case PCA953X_TYPE:
+ case PCAL953X_TYPE:
offset = PCA953X_DIRECTION;
break;
case PCA957X_TYPE:
@@ -302,6 +314,7 @@ static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
mutex_lock(&chip->i2c_lock);
switch (chip->chip_type) {
case PCA953X_TYPE:
+ case PCAL953X_TYPE:
offset = PCA953X_INPUT;
break;
case PCA957X_TYPE:
@@ -337,6 +350,7 @@ static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
switch (chip->chip_type) {
case PCA953X_TYPE:
+ case PCAL953X_TYPE:
offset = PCA953X_OUTPUT;
break;
case PCA957X_TYPE:
@@ -403,6 +417,7 @@ static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
struct pca953x_chip *chip = to_pca(gc);
u8 new_irqs;
int level, i;
+ u8 invert_irq_mask[MAX_BANK];
/* Look for any newly setup interrupt */
for (i = 0; i < NBANK(chip); i++) {
@@ -417,6 +432,17 @@ static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
}
}
+ if (chip->chip_type == PCAL953X_TYPE) {
+ /* 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);
+ }
+
mutex_unlock(&chip->irq_lock);
}
@@ -464,6 +490,29 @@ static bool pca953x_irq_pending(struct pca953x_chip *chip, u8 *pending)
u8 trigger[MAX_BANK];
int ret, i, offset = 0;
+ if (chip->chip_type == PCAL953X_TYPE) {
+ /* Read the current interrupt status from the device */
+ ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
+ if (ret)
+ return 0;
+
+ /* Check latched inputs and clear interrupt status */
+ ret = pca953x_read_regs(chip, PCA953X_INPUT, cur_stat);
+ if (ret)
+ return 0;
+
+ 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;
+ }
+
switch (chip->chip_type) {
case PCA953X_TYPE:
offset = PCA953X_INPUT;
@@ -533,37 +582,47 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
{
struct i2c_client *client = chip->client;
int ret, i, offset = 0;
+ unsigned long flags;
if (client->irq && irq_base != -1
&& (chip->driver_data & PCA_INT)) {
- switch (chip->chip_type) {
- case PCA953X_TYPE:
- offset = PCA953X_INPUT;
- break;
- case PCA957X_TYPE:
- offset = PCA957X_IN;
- break;
+ if (chip->chip_type != PCAL953X_TYPE) {
+ switch (chip->chip_type) {
+ case PCA953X_TYPE:
+ offset = PCA953X_INPUT;
+ break;
+ case PCA957X_TYPE:
+ offset = PCA957X_IN;
+ break;
+ }
+ ret = pca953x_read_regs(chip, offset, 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.
+ */
+ for (i = 0; i < NBANK(chip); i++)
+ chip->irq_stat[i] &= chip->reg_direction[i];
}
- ret = pca953x_read_regs(chip, offset, 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.
- */
- for (i = 0; i < NBANK(chip); i++)
- chip->irq_stat[i] &= chip->reg_direction[i];
mutex_init(&chip->irq_lock);
+ if (chip->chip_type == PCAL953X_TYPE)
+ flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
+ IRQF_SHARED;
+ else
+ flags = IRQF_TRIGGER_LOW | IRQF_ONESHOT |
+ IRQF_SHARED;
+
ret = devm_request_threaded_irq(&client->dev,
client->irq,
NULL,
pca953x_irq_handler,
- IRQF_TRIGGER_LOW | IRQF_ONESHOT |
- IRQF_SHARED,
+ flags,
dev_name(&client->dev), chip);
if (ret) {
dev_err(&client->dev, "failed to request irq %d\n",
@@ -708,7 +767,7 @@ static int pca953x_probe(struct i2c_client *client,
*/
pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
- if (chip->chip_type == PCA953X_TYPE)
+ if (chip->chip_type & (PCA953X_TYPE | PCAL953X_TYPE))
ret = device_pca953x_init(chip, invert);
else
ret = device_pca957x_init(chip, invert);
--
2.1.4
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