linux-kernel - [PATCH 18/23 v6] Input: atmel_mxt_ts - refactor when and how object table is freed

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Date:	Thu, 28 Jun 2012 21:08:19 +0800
From:	Daniel Kurtz <djkurtz@...omium.org>
To:	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Henrik Rydberg <rydberg@...omail.se>,
	Joonyoung Shim <jy0922.shim@...sung.com>,
	Nick Dyer <nick.dyer@...ev.co.uk>,
	Yufeng Shen <miletus@...omium.org>
Cc:	linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
	Olof Johansson <olof@...om.net>,
	Benson Leung <bleung@...omium.org>,
	Daniel Kurtz <djkurtz@...omium.org>
Subject: [PATCH 18/23 v6] Input: atmel_mxt_ts - refactor when and how object table is freed

The Object Table is freed in three cases:
  1) When the driver is being removed.
  2) In the error path of mxt_initialize().
  3) Just after a firmware update, when a new object table is
     about to be read.

For cases 2 & 3, the driver is not immediately unloaded, so this patch
refactors these cases to use a common cleanup function.  It also refactors
the mxt_initialize error paths to ensure that this cleanup happens.

Note: mxt_update_fw_store() does not handle errors during mxt_initialize().
A proposed fix for this is in a subsequent patchset.

Signed-off-by: Daniel Kurtz <djkurtz@...omium.org>
---
 drivers/input/touchscreen/atmel_mxt_ts.c |   23 ++++++++++++++++-------
 1 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index d6b64a0f..488e3e8 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -750,6 +750,12 @@ static int mxt_get_object_table(struct mxt_data *data)
 	return 0;
 }
 
+static void mxt_free_object_table(struct mxt_data *data)
+{
+	kfree(data->object_table);
+	data->object_table = NULL;
+}
+
 static int mxt_initialize(struct mxt_data *data)
 {
 	struct i2c_client *client = data->client;
@@ -772,12 +778,12 @@ static int mxt_initialize(struct mxt_data *data)
 	/* Get object table information */
 	error = mxt_get_object_table(data);
 	if (error)
-		return error;
+		goto err_free_object_table;
 
 	/* Check register init values */
 	error = mxt_check_reg_init(data);
 	if (error)
-		return error;
+		goto err_free_object_table;
 
 	mxt_handle_pdata(data);
 
@@ -795,12 +801,12 @@ static int mxt_initialize(struct mxt_data *data)
 	/* Update matrix size at info struct */
 	error = mxt_read_reg(client, MXT_MATRIX_X_SIZE, &val);
 	if (error)
-		return error;
+		goto err_free_object_table;
 	info->matrix_xsize = val;
 
 	error = mxt_read_reg(client, MXT_MATRIX_Y_SIZE, &val);
 	if (error)
-		return error;
+		goto err_free_object_table;
 	info->matrix_ysize = val;
 
 	dev_info(&client->dev,
@@ -814,6 +820,10 @@ static int mxt_initialize(struct mxt_data *data)
 			info->object_num);
 
 	return 0;
+
+err_free_object_table:
+	mxt_free_object_table(data);
+	return error;
 }
 
 static void mxt_calc_resolution(struct mxt_data *data)
@@ -1000,8 +1010,7 @@ static ssize_t mxt_update_fw_store(struct device *dev,
 		/* Wait for reset */
 		msleep(MXT_FWRESET_TIME);
 
-		kfree(data->object_table);
-		data->object_table = NULL;
+		mxt_free_object_table(data);
 
 		mxt_initialize(data);
 	}
@@ -1128,7 +1137,7 @@ static int __devinit mxt_probe(struct i2c_client *client,
 
 	error = mxt_initialize(data);
 	if (error)
-		goto err_free_object;
+		goto err_free_mem;
 
 	error = request_threaded_irq(client->irq, NULL, mxt_interrupt,
 			pdata->irqflags, client->name, data);
-- 
1.7.7.3

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