[PATCH 1/4] Input: walkera0701 - set up input device's parent

[PATCH 1/4] Input: walkera0701 - set up input device's parent

[Dmitry Torokhov]

This will place the joystick's input device into propoer place in sysfs
hierarchy as long as th port has device assigned to it (i.e. it is not
legacy port).

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/joystick/walkera0701.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/input/joystick/walkera0701.c b/drivers/input/joystick/walkera0701.c
index f8f892b..38386ce 100644
--- a/drivers/input/joystick/walkera0701.c
+++ b/drivers/input/joystick/walkera0701.c
@@ -241,6 +241,7 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 	w->input_dev->id.vendor = 0x0001;
 	w->input_dev->id.product = 0x0001;
 	w->input_dev->id.version = 0x0100;
+	w->input_dev->dev.parent = w->parport->dev;
 	w->input_dev->open = walkera0701_open;
 	w->input_dev->close = walkera0701_close;
 

[PATCH 2/4] Input: walkera0701 - switch to using pr_xxx() for messages

[Dmitry Torokhov]

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/joystick/walkera0701.c |   23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/drivers/input/joystick/walkera0701.c b/drivers/input/joystick/walkera0701.c
index 38386ce..da657e6 100644
--- a/drivers/input/joystick/walkera0701.c
+++ b/drivers/input/joystick/walkera0701.c
@@ -12,7 +12,7 @@
  * the Free Software Foundation.
 */
 
-/* #define WK0701_DEBUG */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #define RESERVE 20000
 #define SYNC_PULSE 1306000
@@ -67,6 +67,7 @@ static inline void walkera0701_parse_frame(struct walkera_dev *w)
 {
 	int i;
 	int val1, val2, val3, val4, val5, val6, val7, val8;
+	int magic, magic_bit;
 	int crc1, crc2;
 
 	for (crc1 = crc2 = i = 0; i < 10; i++) {
@@ -102,17 +103,12 @@ static inline void walkera0701_parse_frame(struct walkera_dev *w)
 	val8 = (w->buf[18] & 1) << 8 | (w->buf[19] << 4) | w->buf[20];
 	val8 *= (w->buf[18] & 2) - 1;	/*sign */
 
-#ifdef WK0701_DEBUG
-	{
-		int magic, magic_bit;
-		magic = (w->buf[21] << 4) | w->buf[22];
-		magic_bit = (w->buf[24] & 8) >> 3;
-		printk(KERN_DEBUG
-		       "walkera0701: %4d %4d %4d %4d  %4d %4d %4d %4d (magic %2x %d)\n",
-		       val1, val2, val3, val4, val5, val6, val7, val8, magic,
-		       magic_bit);
-	}
-#endif
+	magic = (w->buf[21] << 4) | w->buf[22];
+	magic_bit = (w->buf[24] & 8) >> 3;
+	pr_debug("%4d %4d %4d %4d  %4d %4d %4d %4d (magic %2x %d)\n",
+		 val1, val2, val3, val4, val5, val6, val7, val8,
+		 magic, magic_bit);
+
 	input_report_abs(w->input_dev, ABS_X, val2);
 	input_report_abs(w->input_dev, ABS_Y, val1);
 	input_report_abs(w->input_dev, ABS_Z, val6);
@@ -208,7 +204,8 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 		return -ENODEV;
 
 	if (w->parport->irq == -1) {
-		printk(KERN_ERR "walkera0701: parport without interrupt\n");
+		pr_err("parport %d does not have interrupt assigned\n",
+			parport);
 		goto init_err;
 	}
 

[PATCH 3/4] Input: walkera0701 - use proper error codes

[Dmitry Torokhov]

We have been using -EBUSY where we should have used -EIO or -ENOMEM,
so let's fix that and also add some diagnostic messages.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/joystick/walkera0701.c |   56 ++++++++++++++++++++++------------
 1 file changed, 36 insertions(+), 20 deletions(-)

diff --git a/drivers/input/joystick/walkera0701.c b/drivers/input/joystick/walkera0701.c
index da657e6..b86134c 100644
--- a/drivers/input/joystick/walkera0701.c
+++ b/drivers/input/joystick/walkera0701.c
@@ -197,37 +197,51 @@ static void walkera0701_close(struct input_dev *dev)
 
 static int walkera0701_connect(struct walkera_dev *w, int parport)
 {
-	int err = -ENODEV;
+	int error;
 
 	w->parport = parport_find_number(parport);
-	if (w->parport == NULL)
+	if (!w->parport) {
+		pr_err("parport %d does not exist\n", parport);
 		return -ENODEV;
+	}
 
 	if (w->parport->irq == -1) {
 		pr_err("parport %d does not have interrupt assigned\n",
 			parport);
-		goto init_err;
+		error = -EINVAL;
+		goto err_put_parport;
 	}
 
-	err = -EBUSY;
 	w->pardevice = parport_register_device(w->parport, "walkera0701",
 				    NULL, NULL, walkera0701_irq_handler,
 				    PARPORT_DEV_EXCL, w);
-	if (!w->pardevice)
-		goto init_err;
+	if (!w->pardevice) {
+		pr_err("failed to register parport device\n");
+		error = -EIO;
+		goto err_put_parport;
+	}
 
-	if (parport_negotiate(w->pardevice->port, IEEE1284_MODE_COMPAT))
-		goto init_err1;
+	if (parport_negotiate(w->pardevice->port, IEEE1284_MODE_COMPAT)) {
+		pr_err("failed to negotiate parport mode\n");
+		error = -EIO;
+		goto err_unregister_device;
+	}
 
-	if (parport_claim(w->pardevice))
-		goto init_err1;
+	if (parport_claim(w->pardevice)) {
+		pr_err("failed to claim parport\n");
+		error = -EBUSY;
+		goto err_unregister_device;
+	}
 
 	hrtimer_init(&w->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	w->timer.function = timer_handler;
 
 	w->input_dev = input_allocate_device();
-	if (!w->input_dev)
-		goto init_err2;
+	if (!w->input_dev) {
+		pr_err("failed to allocate input device\n");
+		error = -ENOMEM;
+		goto err_release_parport;
+	}
 
 	input_set_drvdata(w->input_dev, w);
 	w->input_dev->name = "Walkera WK-0701 TX";
@@ -252,21 +266,23 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 	input_set_abs_params(w->input_dev, ABS_RUDDER, -512, 512, 0, 0);
 	input_set_abs_params(w->input_dev, ABS_MISC, -512, 512, 0, 0);
 
-	err = input_register_device(w->input_dev);
-	if (err)
-		goto init_err3;
+	error = input_register_device(w->input_dev);
+	if (error) {
+		pr_err("failed to register input device\n");
+		goto err_free_input_dev;
+	}
 
 	return 0;
 
- init_err3:
+err_free_input_dev:
 	input_free_device(w->input_dev);
- init_err2:
+err_release_parport:
 	parport_release(w->pardevice);
- init_err1:
+err_unregister_device:
 	parport_unregister_device(w->pardevice);
- init_err:
+err_put_parport:
 	parport_put_port(w->parport);
-	return err;
+	return error;
 }
 
 static void walkera0701_disconnect(struct walkera_dev *w)

[PATCH 4/4] Input: walkera0701 - claim parport when opening the device

[Dmitry Torokhov]

Postpone claiming the port until the device is opened, instead of doing
that when the driver is loaded.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/joystick/walkera0701.c |   16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/input/joystick/walkera0701.c b/drivers/input/joystick/walkera0701.c
index b86134c..b76ac58 100644
--- a/drivers/input/joystick/walkera0701.c
+++ b/drivers/input/joystick/walkera0701.c
@@ -183,6 +183,9 @@ static int walkera0701_open(struct input_dev *dev)
 {
 	struct walkera_dev *w = input_get_drvdata(dev);
 
+	if (parport_claim(w->pardevice))
+		return -EBUSY;
+
 	parport_enable_irq(w->parport);
 	return 0;
 }
@@ -193,6 +196,8 @@ static void walkera0701_close(struct input_dev *dev)
 
 	parport_disable_irq(w->parport);
 	hrtimer_cancel(&w->timer);
+
+	parport_release(w->pardevice);
 }
 
 static int walkera0701_connect(struct walkera_dev *w, int parport)
@@ -227,12 +232,6 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 		goto err_unregister_device;
 	}
 
-	if (parport_claim(w->pardevice)) {
-		pr_err("failed to claim parport\n");
-		error = -EBUSY;
-		goto err_unregister_device;
-	}
-
 	hrtimer_init(&w->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	w->timer.function = timer_handler;
 
@@ -240,7 +239,7 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 	if (!w->input_dev) {
 		pr_err("failed to allocate input device\n");
 		error = -ENOMEM;
-		goto err_release_parport;
+		goto err_unregister_device;
 	}
 
 	input_set_drvdata(w->input_dev, w);
@@ -276,8 +275,6 @@ static int walkera0701_connect(struct walkera_dev *w, int parport)
 
 err_free_input_dev:
 	input_free_device(w->input_dev);
-err_release_parport:
-	parport_release(w->pardevice);
 err_unregister_device:
 	parport_unregister_device(w->pardevice);
 err_put_parport:
@@ -288,7 +285,6 @@ err_put_parport:
 static void walkera0701_disconnect(struct walkera_dev *w)
 {
 	input_unregister_device(w->input_dev);
-	parport_release(w->pardevice);
 	parport_unregister_device(w->pardevice);
 	parport_put_port(w->parport);
 }