Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Nikita Yushchenko <nikita.yoush@cogentembedded.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Christian Gromm <christian.gromm@microchip.com>,
        Lee Jones <lee.jones@linaro.org>
Cc:     linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org,
        Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Subject: [PATCH 2/2] staging: most: dim2: use device release method
Date:   Tue,  5 Oct 2021 17:34:50 +0300
Message-Id: <20211005143448.8660-2-nikita.yoush@cogentembedded.com>
In-Reply-To: <YVwofSvwGTv3kHjh@kroah.com>
References: <YVwofSvwGTv3kHjh@kroah.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Commit 723de0f9171e ("staging: most: remove device from interface
structure") moved registration of driver-provided struct device to
the most subsystem. This updated dim2 driver as well.

However, struct device passed to register_device() becomes refcounted,
and must not be explicitly deallocated, but must provide release method
instead. Which is incompatible with managing it via devres.

This patch makes the device structure allocated without devres, adds
device release method, and moves device destruction there.

Fixes: 723de0f9171e ("staging: most: remove device from interface structure")
Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
---
 drivers/staging/most/dim2/dim2.c | 55 +++++++++++++++++---------------
 1 file changed, 30 insertions(+), 25 deletions(-)

diff --git a/drivers/staging/most/dim2/dim2.c b/drivers/staging/most/dim2/dim2.c
index bb6dd508e531..4c0c3bc91ac0 100644
--- a/drivers/staging/most/dim2/dim2.c
+++ b/drivers/staging/most/dim2/dim2.c
@@ -734,6 +734,23 @@ static int get_dim2_clk_speed(const char *clock_speed, u8 *val)
 	return -EINVAL;
 }
 
+static void dim2_release(struct device *d)
+{
+	struct dim2_hdm *dev = container_of(d, struct dim2_hdm, dev);
+	unsigned long flags;
+
+	kthread_stop(dev->netinfo_task);
+
+	spin_lock_irqsave(&dim_lock, flags);
+	dim_shutdown();
+	spin_unlock_irqrestore(&dim_lock, flags);
+
+	if (dev->disable_platform)
+		dev->disable_platform(to_platform_device(d->parent));
+
+	kfree(dev);
+}
+
 /*
  * dim2_probe - dim2 probe handler
  * @pdev: platform device structure
@@ -755,7 +772,7 @@ static int dim2_probe(struct platform_device *pdev)
 
 	enum { MLB_INT_IDX, AHB0_INT_IDX };
 
-	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 	if (!dev)
 		return -ENOMEM;
 
@@ -767,19 +784,21 @@ static int dim2_probe(struct platform_device *pdev)
 				      "microchip,clock-speed", &clock_speed);
 	if (ret) {
 		dev_err(&pdev->dev, "missing dt property clock-speed\n");
-		return ret;
+		goto err_free_dev;
 	}
 
 	ret = get_dim2_clk_speed(clock_speed, &dev->clk_speed);
 	if (ret) {
 		dev_err(&pdev->dev, "bad dt property clock-speed\n");
-		return ret;
+		goto err_free_dev;
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	dev->io_base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(dev->io_base))
-		return PTR_ERR(dev->io_base);
+	if (IS_ERR(dev->io_base)) {
+		ret = PTR_ERR(dev->io_base);
+		goto err_free_dev;
+	}
 
 	of_id = of_match_node(dim2_of_match, pdev->dev.of_node);
 	pdata = of_id->data;
@@ -787,7 +806,7 @@ static int dim2_probe(struct platform_device *pdev)
 		if (pdata->enable) {
 			ret = pdata->enable(pdev);
 			if (ret)
-				return ret;
+				goto err_free_dev;
 		}
 		dev->disable_platform = pdata->disable;
 		if (pdata->fcnt)
@@ -882,24 +901,19 @@ static int dim2_probe(struct platform_device *pdev)
 	dev->most_iface.request_netinfo = request_netinfo;
 	dev->most_iface.driver_dev = &pdev->dev;
 	dev->most_iface.dev = &dev->dev;
-	dev->dev.init_name = "dim2_state";
+	dev->dev.init_name = dev->name;
 	dev->dev.parent = &pdev->dev;
+	dev->dev.release = dim2_release;
 
-	ret = most_register_interface(&dev->most_iface);
-	if (ret) {
-		dev_err(&pdev->dev, "failed to register MOST interface\n");
-		goto err_stop_thread;
-	}
-
-	return 0;
+	return most_register_interface(&dev->most_iface);
 
-err_stop_thread:
-	kthread_stop(dev->netinfo_task);
 err_shutdown_dim:
 	dim_shutdown();
 err_disable_platform:
 	if (dev->disable_platform)
 		dev->disable_platform(pdev);
+err_free_dev:
+	kfree(dev);
 
 	return ret;
 }
@@ -913,17 +927,8 @@ static int dim2_probe(struct platform_device *pdev)
 static int dim2_remove(struct platform_device *pdev)
 {
 	struct dim2_hdm *dev = platform_get_drvdata(pdev);
-	unsigned long flags;
 
 	most_deregister_interface(&dev->most_iface);
-	kthread_stop(dev->netinfo_task);
-
-	spin_lock_irqsave(&dim_lock, flags);
-	dim_shutdown();
-	spin_unlock_irqrestore(&dim_lock, flags);
-
-	if (dev->disable_platform)
-		dev->disable_platform(pdev);
 
 	return 0;
 }
-- 
2.30.2