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path: root/drivers/gpio/gpio-pcf857x.c
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Diffstat (limited to 'drivers/gpio/gpio-pcf857x.c')
-rw-r--r--drivers/gpio/gpio-pcf857x.c105
1 files changed, 68 insertions, 37 deletions
diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c
index 9e61bb0719d..1535686e74e 100644
--- a/drivers/gpio/gpio-pcf857x.c
+++ b/drivers/gpio/gpio-pcf857x.c
@@ -26,9 +26,10 @@
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
-#include <linux/workqueue.h>
static const struct i2c_device_id pcf857x_id[] = {
@@ -50,6 +51,27 @@ static const struct i2c_device_id pcf857x_id[] = {
};
MODULE_DEVICE_TABLE(i2c, pcf857x_id);
+#ifdef CONFIG_OF
+static const struct of_device_id pcf857x_of_table[] = {
+ { .compatible = "nxp,pcf8574" },
+ { .compatible = "nxp,pcf8574a" },
+ { .compatible = "nxp,pca8574" },
+ { .compatible = "nxp,pca9670" },
+ { .compatible = "nxp,pca9672" },
+ { .compatible = "nxp,pca9674" },
+ { .compatible = "nxp,pcf8575" },
+ { .compatible = "nxp,pca8575" },
+ { .compatible = "nxp,pca9671" },
+ { .compatible = "nxp,pca9673" },
+ { .compatible = "nxp,pca9675" },
+ { .compatible = "maxim,max7328" },
+ { .compatible = "maxim,max7329" },
+ { .compatible = "ti,tca9554" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, pcf857x_of_table);
+#endif
+
/*
* The pcf857x, pca857x, and pca967x chips only expose one read and one
* write register. Writing a "one" bit (to match the reset state) lets
@@ -66,12 +88,11 @@ struct pcf857x {
struct gpio_chip chip;
struct i2c_client *client;
struct mutex lock; /* protect 'out' */
- struct work_struct work; /* irq demux work */
struct irq_domain *irq_domain; /* for irq demux */
spinlock_t slock; /* protect irq demux */
unsigned out; /* software latch */
unsigned status; /* current status */
- int irq; /* real irq number */
+ unsigned irq_mapped; /* mapped gpio irqs */
int (*write)(struct i2c_client *client, unsigned data);
int (*read)(struct i2c_client *client);
@@ -164,48 +185,54 @@ static void pcf857x_set(struct gpio_chip *chip, unsigned offset, int value)
static int pcf857x_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct pcf857x *gpio = container_of(chip, struct pcf857x, chip);
+ int ret;
- return irq_create_mapping(gpio->irq_domain, offset);
+ ret = irq_create_mapping(gpio->irq_domain, offset);
+ if (ret > 0)
+ gpio->irq_mapped |= (1 << offset);
+
+ return ret;
}
-static void pcf857x_irq_demux_work(struct work_struct *work)
+static irqreturn_t pcf857x_irq(int irq, void *data)
{
- struct pcf857x *gpio = container_of(work,
- struct pcf857x,
- work);
+ struct pcf857x *gpio = data;
unsigned long change, i, status, flags;
status = gpio->read(gpio->client);
spin_lock_irqsave(&gpio->slock, flags);
- change = gpio->status ^ status;
+ /*
+ * call the interrupt handler iff gpio is used as
+ * interrupt source, just to avoid bad irqs
+ */
+
+ change = ((gpio->status ^ status) & gpio->irq_mapped);
for_each_set_bit(i, &change, gpio->chip.ngpio)
generic_handle_irq(irq_find_mapping(gpio->irq_domain, i));
gpio->status = status;
spin_unlock_irqrestore(&gpio->slock, flags);
-}
-
-static irqreturn_t pcf857x_irq_demux(int irq, void *data)
-{
- struct pcf857x *gpio = data;
-
- /*
- * pcf857x can't read/write data here,
- * since i2c data access might go to sleep.
- */
- schedule_work(&gpio->work);
return IRQ_HANDLED;
}
-static int pcf857x_irq_domain_map(struct irq_domain *domain, unsigned int virq,
+static int pcf857x_irq_domain_map(struct irq_domain *domain, unsigned int irq,
irq_hw_number_t hw)
{
- irq_set_chip_and_handler(virq,
+ struct pcf857x *gpio = domain->host_data;
+
+ irq_set_chip_and_handler(irq,
&dummy_irq_chip,
handle_level_irq);
+#ifdef CONFIG_ARM
+ set_irq_flags(irq, IRQF_VALID);
+#else
+ irq_set_noprobe(irq);
+#endif
+ gpio->irq_mapped |= (1 << hw);
+
return 0;
}
@@ -218,8 +245,6 @@ static void pcf857x_irq_domain_cleanup(struct pcf857x *gpio)
if (gpio->irq_domain)
irq_domain_remove(gpio->irq_domain);
- if (gpio->irq)
- free_irq(gpio->irq, gpio);
}
static int pcf857x_irq_domain_init(struct pcf857x *gpio,
@@ -230,20 +255,21 @@ static int pcf857x_irq_domain_init(struct pcf857x *gpio,
gpio->irq_domain = irq_domain_add_linear(client->dev.of_node,
gpio->chip.ngpio,
&pcf857x_irq_domain_ops,
- NULL);
+ gpio);
if (!gpio->irq_domain)
goto fail;
/* enable real irq */
- status = request_irq(client->irq, pcf857x_irq_demux, 0,
- dev_name(&client->dev), gpio);
+ status = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, pcf857x_irq, IRQF_ONESHOT |
+ IRQF_TRIGGER_FALLING,
+ dev_name(&client->dev), gpio);
+
if (status)
goto fail;
/* enable gpio_to_irq() */
- INIT_WORK(&gpio->work, pcf857x_irq_demux_work);
gpio->chip.to_irq = pcf857x_to_irq;
- gpio->irq = client->irq;
return 0;
@@ -257,14 +283,18 @@ fail:
static int pcf857x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- struct pcf857x_platform_data *pdata;
+ struct pcf857x_platform_data *pdata = dev_get_platdata(&client->dev);
+ struct device_node *np = client->dev.of_node;
struct pcf857x *gpio;
+ unsigned int n_latch = 0;
int status;
- pdata = dev_get_platdata(&client->dev);
- if (!pdata) {
+ if (IS_ENABLED(CONFIG_OF) && np)
+ of_property_read_u32(np, "lines-initial-states", &n_latch);
+ else if (pdata)
+ n_latch = pdata->n_latch;
+ else
dev_dbg(&client->dev, "no platform data\n");
- }
/* Allocate, initialize, and register this gpio_chip. */
gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
@@ -357,11 +387,11 @@ static int pcf857x_probe(struct i2c_client *client,
* may cause transient glitching since it can't know the last value
* written (some pins may need to be driven low).
*
- * Using pdata->n_latch avoids that trouble. When left initialized
- * to zero, our software copy of the "latch" then matches the chip's
- * all-ones reset state. Otherwise it flags pins to be driven low.
+ * Using n_latch avoids that trouble. When left initialized to zero,
+ * our software copy of the "latch" then matches the chip's all-ones
+ * reset state. Otherwise it flags pins to be driven low.
*/
- gpio->out = pdata ? ~pdata->n_latch : ~0;
+ gpio->out = ~n_latch;
gpio->status = gpio->out;
status = gpiochip_add(&gpio->chip);
@@ -423,6 +453,7 @@ static struct i2c_driver pcf857x_driver = {
.driver = {
.name = "pcf857x",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(pcf857x_of_table),
},
.probe = pcf857x_probe,
.remove = pcf857x_remove,
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-27 03:52:05 +0000