1 files changed, 57 insertions, 103 deletions

diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 210b6f7b9028..d6ef91b888c6 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -1,28 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * GPIO-based I2C Arbitration Using a Challenge & Response Mechanism
  *
  * Copyright (C) 2012 Google, Inc
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  */
 
 #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/init.h>
 #include <linux/module.h>
-#include <linux/of_i2c.h>
-#include <linux/of_gpio.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
@@ -30,55 +18,45 @@
 /**
  * struct i2c_arbitrator_data - Driver data for I2C arbitrator
  *
- * @parent: Parent adapter
- * @child: Child bus
- * @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 {
-	struct i2c_adapter *parent;
-	struct i2c_adapter *child;
-	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;
 };
 
 
-/**
+/*
  * i2c_arbitrator_select - claim the I2C bus
  *
  * Use the GPIO-based signalling protocol; return -EBUSY if we fail.
  */
-static int i2c_arbitrator_select(struct i2c_adapter *adap, void *data, u32 chan)
+static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan)
 {
-	const struct i2c_arbitrator_data *arb = data;
+	const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc);
 	unsigned long stop_retry, stop_time;
 
 	/* Start a round of trying to claim the bus */
 	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;
 			}
@@ -87,30 +65,29 @@ static int i2c_arbitrator_select(struct i2c_adapter *adap, void *data, 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(&adap->dev, "Could not claim bus, timeout\n");
+	dev_err(muxc->dev, "Could not claim bus, timeout\n");
 	return -EBUSY;
 }
 
-/**
+/*
  * i2c_arbitrator_deselect - release the I2C bus
  *
  * Release the I2C bus using the GPIO-based signalling protocol.
  */
-static int i2c_arbitrator_deselect(struct i2c_adapter *adap, void *data,
-				   u32 chan)
+static int i2c_arbitrator_deselect(struct i2c_mux_core *muxc, u32 chan)
 {
-	const struct i2c_arbitrator_data *arb = data;
+	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;
@@ -121,9 +98,9 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
 	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 */
@@ -131,57 +108,41 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
 		dev_err(dev, "Cannot find device tree node\n");
 		return -ENODEV;
 	}
-	if (dev->platform_data) {
+	if (dev_get_platdata(dev)) {
 		dev_err(dev, "Platform data is not supported\n");
 		return -EINVAL;
 	}
 
-	arb = devm_kzalloc(dev, sizeof(*arb), GFP_KERNEL);
-	if (!arb) {
-		dev_err(dev, "Cannot allocate i2c_arbitrator_data\n");
+	muxc = i2c_mux_alloc(NULL, dev, 1, sizeof(*arb), I2C_MUX_ARBITRATOR,
+			     i2c_arbitrator_select, i2c_arbitrator_deselect);
+	if (!muxc)
 		return -ENOMEM;
-	}
-	platform_set_drvdata(pdev, arb);
-
-	/* 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;
-	}
+	arb = i2c_mux_priv(muxc);
 
-	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;
+	platform_set_drvdata(pdev, muxc);
+
+	/* 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);
 	}
-	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 */
@@ -198,33 +159,27 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
 		dev_err(dev, "Cannot parse i2c-parent\n");
 		return -EINVAL;
 	}
-	arb->parent = of_find_i2c_adapter_by_node(parent_np);
-	if (!arb->parent) {
+	muxc->parent = of_get_i2c_adapter_by_node(parent_np);
+	of_node_put(parent_np);
+	if (!muxc->parent) {
 		dev_err(dev, "Cannot find parent bus\n");
-		return -EINVAL;
+		return -EPROBE_DEFER;
 	}
 
 	/* Actually add the mux adapter */
-	arb->child = i2c_add_mux_adapter(arb->parent, dev, arb, 0, 0, 0,
-					 i2c_arbitrator_select,
-					 i2c_arbitrator_deselect);
-	if (!arb->child) {
-		dev_err(dev, "Failed to add adapter\n");
-		ret = -ENODEV;
-		i2c_put_adapter(arb->parent);
-	}
+	ret = i2c_mux_add_adapter(muxc, 0, 0);
+	if (ret)
+		i2c_put_adapter(muxc->parent);
 
 	return ret;
 }
 
-static int i2c_arbitrator_remove(struct platform_device *pdev)
+static void i2c_arbitrator_remove(struct platform_device *pdev)
 {
-	struct i2c_arbitrator_data *arb = platform_get_drvdata(pdev);
+	struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
 
-	i2c_del_mux_adapter(arb->child);
-	i2c_put_adapter(arb->parent);
-
-	return 0;
+	i2c_mux_del_adapters(muxc);
+	i2c_put_adapter(muxc->parent);
 }
 
 static const struct of_device_id i2c_arbitrator_of_match[] = {
@@ -235,11 +190,10 @@ MODULE_DEVICE_TABLE(of, i2c_arbitrator_of_match);
 
 static struct platform_driver i2c_arbitrator_driver = {
 	.probe	= i2c_arbitrator_probe,
-	.remove	= i2c_arbitrator_remove,
+	.remove = i2c_arbitrator_remove,
 	.driver	= {
-		.owner	= THIS_MODULE,
 		.name	= "i2c-arb-gpio-challenge",
-		.of_match_table = of_match_ptr(i2c_arbitrator_of_match),
+		.of_match_table = i2c_arbitrator_of_match,
 	},
 };