[PATCH v3 2/5] i2c: pca-platform: switch to struct gpio_desc
From: Chris Packham
Date: Sun Jun 25 2017 - 20:45:10 EST
Make use of struct gpio_desc which allows us to specify the active state
of the reset pin.
Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
---
Changes in v3:
- New, replaces "i2c: pca-platform: use gpio_is_valid"
- Using struct gpio_desc is required to make the flags stick. Because those
flags now correctly indicate that RESET_N is active low, the logic for
resetting the chip is inverted.
drivers/i2c/busses/i2c-pca-platform.c | 43 ++++++++++++++++-------------------
1 file changed, 19 insertions(+), 24 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c
index 3bd2e7d06e4b..9f995b8ed587 100644
--- a/drivers/i2c/busses/i2c-pca-platform.c
+++ b/drivers/i2c/busses/i2c-pca-platform.c
@@ -22,6 +22,7 @@
#include <linux/i2c-algo-pca.h>
#include <linux/i2c-pca-platform.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/io.h>
#include <asm/irq.h>
@@ -29,7 +30,7 @@
struct i2c_pca_pf_data {
void __iomem *reg_base;
int irq; /* if 0, use polling */
- int gpio;
+ struct gpio_desc *gpio;
wait_queue_head_t wait;
struct i2c_adapter adap;
struct i2c_algo_pca_data algo_data;
@@ -112,9 +113,9 @@ static void i2c_pca_pf_resetchip(void *pd)
{
struct i2c_pca_pf_data *i2c = pd;
- gpio_set_value(i2c->gpio, 0);
+ gpiod_set_value(i2c->gpio, 1);
ndelay(100);
- gpio_set_value(i2c->gpio, 1);
+ gpiod_set_value(i2c->gpio, 0);
}
static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
@@ -181,11 +182,24 @@ static int i2c_pca_pf_probe(struct platform_device *pdev)
if (platform_data) {
i2c->adap.timeout = platform_data->timeout;
i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
- i2c->gpio = platform_data->gpio;
+ if (gpio_is_valid(platform_data->gpio)) {
+ ret = devm_gpio_request_one(&pdev->dev,
+ platform_data->gpio,
+ GPIOF_ACTIVE_LOW,
+ i2c->adap.name);
+ if (ret == 0) {
+ i2c->gpio = gpio_to_desc(platform_data->gpio);
+ gpiod_direction_output(i2c->gpio, 0);
+ i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
+ } else {
+ dev_warn(&pdev->dev, "Registering gpio failed!\n");
+ i2c->gpio = NULL;
+ }
+ }
} else {
i2c->adap.timeout = HZ;
i2c->algo_data.i2c_clock = 59000;
- i2c->gpio = -1;
+ i2c->gpio = NULL;
}
i2c->algo_data.data = i2c;
@@ -208,19 +222,6 @@ static int i2c_pca_pf_probe(struct platform_device *pdev)
break;
}
- /* Use gpio_is_valid() when in mainline */
- if (i2c->gpio > -1) {
- ret = gpio_request(i2c->gpio, i2c->adap.name);
- if (ret == 0) {
- gpio_direction_output(i2c->gpio, 1);
- i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
- } else {
- printk(KERN_WARNING "%s: Registering gpio failed!\n",
- i2c->adap.name);
- i2c->gpio = ret;
- }
- }
-
if (irq) {
ret = request_irq(irq, i2c_pca_pf_handler,
IRQF_TRIGGER_FALLING, pdev->name, i2c);
@@ -243,9 +244,6 @@ static int i2c_pca_pf_probe(struct platform_device *pdev)
if (irq)
free_irq(irq, i2c);
e_reqirq:
- if (i2c->gpio > -1)
- gpio_free(i2c->gpio);
-
iounmap(i2c->reg_base);
e_remap:
kfree(i2c);
@@ -265,9 +263,6 @@ static int i2c_pca_pf_remove(struct platform_device *pdev)
if (i2c->irq)
free_irq(i2c->irq, i2c);
- if (i2c->gpio > -1)
- gpio_free(i2c->gpio);
-
iounmap(i2c->reg_base);
release_mem_region(i2c->io_base, i2c->io_size);
kfree(i2c);
--
2.13.0