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-rw-r--r--drivers/i2c/muxes/i2c-arb-gpio-challenge.c79
1 files changed, 27 insertions, 52 deletions
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 812b8cff265f..a664f637bc3d 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -15,12 +15,11 @@
*/
#include <linux/delay.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/kernel.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/module.h>
-#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
@@ -28,22 +27,16 @@
/**
* struct i2c_arbitrator_data - Driver data for I2C arbitrator
*
- * @our_gpio: GPIO we'll use to claim.
- * @our_gpio_release: 0 if active high; 1 if active low; AKA if the GPIO ==
- * this then consider it released.
- * @their_gpio: GPIO that the other side will use to claim.
- * @their_gpio_release: 0 if active high; 1 if active low; AKA if the GPIO ==
- * this then consider it released.
+ * @our_gpio: GPIO descriptor we'll use to claim.
+ * @their_gpio: GPIO descriptor that the other side will use to claim.
* @slew_delay_us: microseconds to wait for a GPIO to go high.
* @wait_retry_us: we'll attempt another claim after this many microseconds.
* @wait_free_us: we'll give up after this many microseconds.
*/
struct i2c_arbitrator_data {
- int our_gpio;
- int our_gpio_release;
- int their_gpio;
- int their_gpio_release;
+ struct gpio_desc *our_gpio;
+ struct gpio_desc *their_gpio;
unsigned int slew_delay_us;
unsigned int wait_retry_us;
unsigned int wait_free_us;
@@ -64,15 +57,15 @@ static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan)
stop_time = jiffies + usecs_to_jiffies(arb->wait_free_us) + 1;
do {
/* Indicate that we want to claim the bus */
- gpio_set_value(arb->our_gpio, !arb->our_gpio_release);
+ gpiod_set_value(arb->our_gpio, 1);
udelay(arb->slew_delay_us);
/* Wait for the other master to release it */
stop_retry = jiffies + usecs_to_jiffies(arb->wait_retry_us) + 1;
while (time_before(jiffies, stop_retry)) {
- int gpio_val = !!gpio_get_value(arb->their_gpio);
+ int gpio_val = gpiod_get_value(arb->their_gpio);
- if (gpio_val == arb->their_gpio_release) {
+ if (!gpio_val) {
/* We got it, so return */
return 0;
}
@@ -81,13 +74,13 @@ static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan)
}
/* It didn't release, so give up, wait, and try again */
- gpio_set_value(arb->our_gpio, arb->our_gpio_release);
+ gpiod_set_value(arb->our_gpio, 0);
usleep_range(arb->wait_retry_us, arb->wait_retry_us * 2);
} while (time_before(jiffies, stop_time));
/* Give up, release our claim */
- gpio_set_value(arb->our_gpio, arb->our_gpio_release);
+ gpiod_set_value(arb->our_gpio, 0);
udelay(arb->slew_delay_us);
dev_err(muxc->dev, "Could not claim bus, timeout\n");
return -EBUSY;
@@ -103,7 +96,7 @@ static int i2c_arbitrator_deselect(struct i2c_mux_core *muxc, u32 chan)
const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc);
/* Release the bus and wait for the other master to notice */
- gpio_set_value(arb->our_gpio, arb->our_gpio_release);
+ gpiod_set_value(arb->our_gpio, 0);
udelay(arb->slew_delay_us);
return 0;
@@ -116,8 +109,7 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
struct device_node *parent_np;
struct i2c_mux_core *muxc;
struct i2c_arbitrator_data *arb;
- enum of_gpio_flags gpio_flags;
- unsigned long out_init;
+ struct gpio_desc *dummy;
int ret;
/* We only support probing from device tree; no platform_data */
@@ -138,45 +130,28 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, muxc);
- /* Request GPIOs */
- ret = of_get_named_gpio_flags(np, "our-claim-gpio", 0, &gpio_flags);
- if (!gpio_is_valid(ret)) {
- if (ret != -EPROBE_DEFER)
- dev_err(dev, "Error getting our-claim-gpio\n");
- return ret;
- }
- arb->our_gpio = ret;
- arb->our_gpio_release = !!(gpio_flags & OF_GPIO_ACTIVE_LOW);
- out_init = (gpio_flags & OF_GPIO_ACTIVE_LOW) ?
- GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
- ret = devm_gpio_request_one(dev, arb->our_gpio, out_init,
- "our-claim-gpio");
- if (ret) {
- if (ret != -EPROBE_DEFER)
- dev_err(dev, "Error requesting our-claim-gpio\n");
- return ret;
+ /* Request GPIOs, our GPIO as unclaimed to begin with */
+ arb->our_gpio = devm_gpiod_get(dev, "our-claim", GPIOD_OUT_LOW);
+ if (IS_ERR(arb->our_gpio)) {
+ dev_err(dev, "could not get \"our-claim\" GPIO (%ld)\n",
+ PTR_ERR(arb->our_gpio));
+ return PTR_ERR(arb->our_gpio);
}
- ret = of_get_named_gpio_flags(np, "their-claim-gpios", 0, &gpio_flags);
- if (!gpio_is_valid(ret)) {
- if (ret != -EPROBE_DEFER)
- dev_err(dev, "Error getting their-claim-gpio\n");
- return ret;
- }
- arb->their_gpio = ret;
- arb->their_gpio_release = !!(gpio_flags & OF_GPIO_ACTIVE_LOW);
- ret = devm_gpio_request_one(dev, arb->their_gpio, GPIOF_IN,
- "their-claim-gpio");
- if (ret) {
- if (ret != -EPROBE_DEFER)
- dev_err(dev, "Error requesting their-claim-gpio\n");
- return ret;
+ arb->their_gpio = devm_gpiod_get(dev, "their-claim", GPIOD_IN);
+ if (IS_ERR(arb->their_gpio)) {
+ dev_err(dev, "could not get \"their-claim\" GPIO (%ld)\n",
+ PTR_ERR(arb->their_gpio));
+ return PTR_ERR(arb->their_gpio);
}
/* At the moment we only support a single two master (us + 1 other) */
- if (gpio_is_valid(of_get_named_gpio(np, "their-claim-gpios", 1))) {
+ dummy = devm_gpiod_get_index(dev, "their-claim", 1, GPIOD_IN);
+ if (!IS_ERR(dummy)) {
dev_err(dev, "Only one other master is supported\n");
return -EINVAL;
+ } else if (PTR_ERR(dummy) == -EPROBE_DEFER) {
+ return -EPROBE_DEFER;
}
/* Arbitration parameters */