V4L/DVB (7995): si470x: a lot of small code cleanups

This patch brings the following changes:
- comment on how to listen to an usb audio device
  (i get so many questions about that...)
- code cleanup (error handling, more warnings, spacing, ...)

Signed-off-by: Tobias Lorenz <tobias.lorenz@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 196 insertions, 90 deletions

diff --git a/drivers/media/radio/radio-si470x.c b/drivers/media/radio/radio-si470x.c
index 7df1163d7097..954ba997895d 100644
--- a/drivers/media/radio/radio-si470x.c
+++ b/drivers/media/radio/radio-si470x.c
@@ -101,7 +101,7 @@
  *              - unplugging fixed
  * 2008-05-07   Tobias Lorenz <tobias.lorenz@gmx.net>
  *              Version 1.0.8
- *              - let si470x_get_freq return errno
+ *              - more safety checks, let si470x_get_freq return errno
  *
  * ToDo:
  * - add seeking support
@@ -487,11 +487,11 @@ static int si470x_get_report(struct si470x_device *radio, void *buf, int size)
                 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
                 report[0], 2,
                 buf, size, usb_timeout);
+
         if (retval < 0)
                 printk(KERN_WARNING DRIVER_NAME
                         ": si470x_get_report: usb_control_msg returned %d\n",
                         retval);
-
         return retval;
 }
 
@@ -510,11 +510,11 @@ static int si470x_set_report(struct si470x_device *radio, void *buf, int size)
                 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
                 report[0], 2,
                 buf, size, usb_timeout);
+
         if (retval < 0)
                 printk(KERN_WARNING DRIVER_NAME
                         ": si470x_set_report: usb_control_msg returned %d\n",
                         retval);
-
         return retval;
 }
 
@@ -623,24 +623,30 @@ static int si470x_set_chan(struct si470x_device *radio, unsigned short chan)
         radio->registers[CHANNEL] |= CHANNEL_TUNE | chan;
         retval = si470x_set_register(radio, CHANNEL);
         if (retval < 0)
-                return retval;
+                goto done;
 
-        /* wait till seek operation has completed */
+        /* wait till tune operation has completed */
         timeout = jiffies + msecs_to_jiffies(tune_timeout);
         do {
                 retval = si470x_get_register(radio, STATUSRSSI);
                 if (retval < 0)
-                        return retval;
+                        goto stop;
                 timed_out = time_after(jiffies, timeout);
         } while (((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0) &&
                 (!timed_out));
+        if ((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
+                printk(KERN_WARNING DRIVER_NAME ": tune does not complete\n");
         if (timed_out)
                 printk(KERN_WARNING DRIVER_NAME
-                        ": seek does not finish after %u ms\n", tune_timeout);
+                        ": tune timed out after %u ms\n", tune_timeout);
 
+stop:
         /* stop tuning */
         radio->registers[CHANNEL] &= ~CHANNEL_TUNE;
-        return si470x_set_register(radio, CHANNEL);
+        retval = si470x_set_register(radio, CHANNEL);
+
+done:
+        return retval;
 }
 
 
@@ -731,27 +737,30 @@ static int si470x_start(struct si470x_device *radio)
                 POWERCFG_DMUTE | POWERCFG_ENABLE | POWERCFG_RDSM;
         retval = si470x_set_register(radio, POWERCFG);
         if (retval < 0)
-                return retval;
+                goto done;
 
         /* sysconfig 1 */
         radio->registers[SYSCONFIG1] = SYSCONFIG1_DE;
         retval = si470x_set_register(radio, SYSCONFIG1);
         if (retval < 0)
-                return retval;
+                goto done;
 
         /* sysconfig 2 */
         radio->registers[SYSCONFIG2] =
-                (0x3f  << 8) |  /* SEEKTH */
-                (band  << 6) |  /* BAND */
-                (space << 4) |  /* SPACE */
-                15;             /* VOLUME (max) */
+                (0x3f  << 8) |                          /* SEEKTH */
+                ((band  << 6) & SYSCONFIG2_BAND)  |     /* BAND */
+                ((space << 4) & SYSCONFIG2_SPACE) |     /* SPACE */
+                15;                                     /* VOLUME (max) */
         retval = si470x_set_register(radio, SYSCONFIG2);
         if (retval < 0)
-                return retval;
+                goto done;
 
         /* reset last channel */
-        return si470x_set_chan(radio,
+        retval = si470x_set_chan(radio,
                 radio->registers[CHANNEL] & CHANNEL_CHAN);
+
+done:
+        return retval;
 }
 
 
@@ -766,13 +775,16 @@ static int si470x_stop(struct si470x_device *radio)
         radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_RDS;
         retval = si470x_set_register(radio, SYSCONFIG1);
         if (retval < 0)
-                return retval;
+                goto done;
 
         /* powercfg */
         radio->registers[POWERCFG] &= ~POWERCFG_DMUTE;
         /* POWERCFG_ENABLE has to automatically go low */
         radio->registers[POWERCFG] |= POWERCFG_ENABLE | POWERCFG_DISABLE;
-        return si470x_set_register(radio, POWERCFG);
+        retval = si470x_set_register(radio, POWERCFG);
+
+done:
+        return retval;
 }
 
 
@@ -889,6 +901,7 @@ static void si470x_work(struct work_struct *work)
         struct si470x_device *radio = container_of(work, struct si470x_device,
                 work.work);
 
+        /* safety checks */
         if (radio->disconnected)
                 return;
         if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
@@ -923,11 +936,15 @@ static ssize_t si470x_fops_read(struct file *file, char __user *buf,
 
         /* block if no new data available */
         while (radio->wr_index == radio->rd_index) {
-                if (file->f_flags & O_NONBLOCK)
-                        return -EWOULDBLOCK;
+                if (file->f_flags & O_NONBLOCK) {
+                        retval = -EWOULDBLOCK;
+                        goto done;
+                }
                 if (wait_event_interruptible(radio->read_queue,
-                        radio->wr_index != radio->rd_index) < 0)
-                        return -EINTR;
+                        radio->wr_index != radio->rd_index) < 0) {
+                        retval = -EINTR;
+                        goto done;
+                }
         }
 
         /* calculate block count from byte count */
@@ -956,6 +973,7 @@ static ssize_t si470x_fops_read(struct file *file, char __user *buf,
         }
         mutex_unlock(&radio->lock);
 
+done:
         return retval;
 }
 
@@ -967,6 +985,7 @@ static unsigned int si470x_fops_poll(struct file *file,
                 struct poll_table_struct *pts)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
+        int retval = 0;
 
         /* switch on rds reception */
         if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0) {
@@ -978,9 +997,9 @@ static unsigned int si470x_fops_poll(struct file *file,
         poll_wait(file, &radio->read_queue, pts);
 
         if (radio->rd_index != radio->wr_index)
-                return POLLIN | POLLRDNORM;
+                retval = POLLIN | POLLRDNORM;
 
-        return 0;
+        return retval;
 }
 
 
@@ -997,17 +1016,18 @@ static int si470x_fops_open(struct inode *inode, struct file *file)
         retval = usb_autopm_get_interface(radio->intf);
         if (retval < 0) {
                 radio->users--;
-                return -EIO;
+                retval = -EIO;
+                goto done;
         }
 
         if (radio->users == 1) {
                 retval = si470x_start(radio);
                 if (retval < 0)
                         usb_autopm_put_interface(radio->intf);
-                return retval;
         }
 
-        return 0;
+done:
+        return retval;
 }
 
 
@@ -1019,8 +1039,11 @@ static int si470x_fops_release(struct inode *inode, struct file *file)
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
         int retval = 0;
 
-        if (!radio)
-                return -ENODEV;
+        /* safety check */
+        if (!radio) {
+                retval = -ENODEV;
+                goto done;
+        }
 
         mutex_lock(&radio->disconnect_lock);
         radio->users--;
@@ -1044,6 +1067,8 @@ static int si470x_fops_release(struct inode *inode, struct file *file)
 
 unlock:
         mutex_unlock(&radio->disconnect_lock);
+
+done:
         return retval;
 }
 
@@ -1131,7 +1156,7 @@ static int si470x_vidioc_querycap(struct file *file, void *priv,
 /*
  * si470x_vidioc_g_input - get input
  */
-static int si470x_vidioc_g_input(struct file *filp, void *priv,
+static int si470x_vidioc_g_input(struct file *file, void *priv,
                 unsigned int *i)
 {
         *i = 0;
@@ -1143,12 +1168,18 @@ static int si470x_vidioc_g_input(struct file *filp, void *priv,
 /*
  * si470x_vidioc_s_input - set input
  */
-static int si470x_vidioc_s_input(struct file *filp, void *priv, unsigned int i)
+static int si470x_vidioc_s_input(struct file *file, void *priv, unsigned int i)
 {
+        int retval = 0;
+
+        /* safety checks */
         if (i != 0)
-                return -EINVAL;
+                retval = -EINVAL;
 
-        return 0;
+        if (retval < 0)
+                printk(KERN_WARNING DRIVER_NAME
+                        ": set input failed with %d\n", retval);
+        return retval;
 }
 
 
@@ -1161,17 +1192,22 @@ static int si470x_vidioc_queryctrl(struct file *file, void *priv,
         unsigned char i;
         int retval = -EINVAL;
 
+        /* safety checks */
+        if (!qc->id)
+                goto done;
+
         for (i = 0; i < ARRAY_SIZE(si470x_v4l2_queryctrl); i++) {
-                if (qc->id && qc->id == si470x_v4l2_queryctrl[i].id) {
+                if (qc->id == si470x_v4l2_queryctrl[i].id) {
                         memcpy(qc, &(si470x_v4l2_queryctrl[i]), sizeof(*qc));
                         retval = 0;
                         break;
                 }
         }
+
+done:
         if (retval < 0)
                 printk(KERN_WARNING DRIVER_NAME
-                        ": query control failed with %d\n", retval);
-
+                        ": query controls failed with %d\n", retval);
         return retval;
 }
 
@@ -1183,9 +1219,13 @@ static int si470x_vidioc_g_ctrl(struct file *file, void *priv,
                 struct v4l2_control *ctrl)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
+        int retval = 0;
 
-        if (radio->disconnected)
-                return -EIO;
+        /* safety checks */
+        if (radio->disconnected) {
+                retval = -EIO;
+                goto done;
+        }
 
         switch (ctrl->id) {
         case V4L2_CID_AUDIO_VOLUME:
@@ -1196,9 +1236,15 @@ static int si470x_vidioc_g_ctrl(struct file *file, void *priv,
                 ctrl->value = ((radio->registers[POWERCFG] &
                                 POWERCFG_DMUTE) == 0) ? 1 : 0;
                 break;
+        default:
+                retval = -EINVAL;
         }
 
-        return 0;
+done:
+        if (retval < 0)
+                printk(KERN_WARNING DRIVER_NAME
+                        ": get control failed with %d\n", retval);
+        return retval;
 }
 
 
@@ -1209,10 +1255,13 @@ static int si470x_vidioc_s_ctrl(struct file *file, void *priv,
                 struct v4l2_control *ctrl)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
-        int retval;
+        int retval = 0;
 
-        if (radio->disconnected)
-                return -EIO;
+        /* safety checks */
+        if (radio->disconnected) {
+                retval = -EIO;
+                goto done;
+        }
 
         switch (ctrl->id) {
         case V4L2_CID_AUDIO_VOLUME:
@@ -1230,10 +1279,11 @@ static int si470x_vidioc_s_ctrl(struct file *file, void *priv,
         default:
                 retval = -EINVAL;
         }
+
+done:
         if (retval < 0)
                 printk(KERN_WARNING DRIVER_NAME
                         ": set control failed with %d\n", retval);
-
         return retval;
 }
 
@@ -1244,13 +1294,22 @@ static int si470x_vidioc_s_ctrl(struct file *file, void *priv,
 static int si470x_vidioc_g_audio(struct file *file, void *priv,
                 struct v4l2_audio *audio)
 {
-        if (audio->index > 1)
-                return -EINVAL;
+        int retval = 0;
+
+        /* safety checks */
+        if (audio->index != 0) {
+                retval = -EINVAL;
+                goto done;
+        }
 
         strcpy(audio->name, "Radio");
         audio->capability = V4L2_AUDCAP_STEREO;
 
-        return 0;
+done:
+        if (retval < 0)
+                printk(KERN_WARNING DRIVER_NAME
+                        ": get audio failed with %d\n", retval);
+        return retval;
 }
 
 
@@ -1260,10 +1319,19 @@ static int si470x_vidioc_g_audio(struct file *file, void *priv,
 static int si470x_vidioc_s_audio(struct file *file, void *priv,
                 struct v4l2_audio *audio)
 {
-        if (audio->index != 0)
-                return -EINVAL;
+        int retval = 0;
 
-        return 0;
+        /* safety checks */
+        if (audio->index != 0) {
+                retval = -EINVAL;
+                goto done;
+        }
+
+done:
+        if (retval < 0)
+                printk(KERN_WARNING DRIVER_NAME
+                        ": set audio failed with %d\n", retval);
+        return retval;
 }
 
 
@@ -1274,20 +1342,23 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv,
                 struct v4l2_tuner *tuner)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
-        int retval;
+        int retval = 0;
 
-        if (radio->disconnected)
-                return -EIO;
-        if (tuner->index > 0)
-                return -EINVAL;
+        /* safety checks */
+        if (radio->disconnected) {
+                retval = -EIO;
+                goto done;
+        }
+        if ((tuner->index != 0) && (tuner->type != V4L2_TUNER_RADIO)) {
+                retval = -EINVAL;
+                goto done;
+        }
 
-        /* read status rssi */
         retval = si470x_get_register(radio, STATUSRSSI);
         if (retval < 0)
-                return retval;
+                goto done;
 
         strcpy(tuner->name, "FM");
-        tuner->type = V4L2_TUNER_RADIO;
         switch (band) {
         /* 0: 87.5 - 108 MHz (USA, Europe, default) */
         default:
@@ -1321,7 +1392,11 @@ static int si470x_vidioc_g_tuner(struct file *file, void *priv,
         /* automatic frequency control: -1: freq to low, 1 freq to high */
         tuner->afc = 0;
 
-        return 0;
+done:
+        if (retval < 0)
+                printk(KERN_WARNING DRIVER_NAME
+                        ": get tuner failed with %d\n", retval);
+        return retval;
 }
 
 
@@ -1332,12 +1407,17 @@ static int si470x_vidioc_s_tuner(struct file *file, void *priv,
                 struct v4l2_tuner *tuner)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
-        int retval;
+        int retval = 0;
 
-        if (radio->disconnected)
-                return -EIO;
-        if (tuner->index > 0)
-                return -EINVAL;
+        /* safety checks */
+        if (radio->disconnected) {
+                retval = -EIO;
+                goto done;
+        }
+        if ((tuner->index != 0) && (tuner->type != V4L2_TUNER_RADIO)) {
+                retval = -EINVAL;
+                goto done;
+        }
 
         if (tuner->audmode == V4L2_TUNER_MODE_MONO)
                 radio->registers[POWERCFG] |= POWERCFG_MONO;  /* force mono */
@@ -1345,10 +1425,11 @@ static int si470x_vidioc_s_tuner(struct file *file, void *priv,
                 radio->registers[POWERCFG] &= ~POWERCFG_MONO; /* try stereo */
 
         retval = si470x_set_register(radio, POWERCFG);
+
+done:
         if (retval < 0)
                 printk(KERN_WARNING DRIVER_NAME
                         ": set tuner failed with %d\n", retval);
-
         return retval;
 }
 
@@ -1360,12 +1441,25 @@ static int si470x_vidioc_g_frequency(struct file *file, void *priv,
                 struct v4l2_frequency *freq)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
+        int retval = 0;
 
-        if (radio->disconnected)
-                return -EIO;
+        /* safety checks */
+        if (radio->disconnected) {
+                retval = -EIO;
+                goto done;
+        }
+        if ((freq->tuner != 0) && (freq->type != V4L2_TUNER_RADIO)) {
+                retval = -EINVAL;
+                goto done;
+        }
+
+        retval = si470x_get_freq(radio, &freq->frequency);
 
-        freq->type = V4L2_TUNER_RADIO;
-        return si470x_get_freq(radio, &radio->frequency);
+done:
+        if (retval < 0)
+                printk(KERN_WARNING DRIVER_NAME
+                        ": get frequency failed with %d\n", retval);
+        return retval;
 }
 
 
@@ -1376,19 +1470,25 @@ static int si470x_vidioc_s_frequency(struct file *file, void *priv,
                 struct v4l2_frequency *freq)
 {
         struct si470x_device *radio = video_get_drvdata(video_devdata(file));
-        int retval;
+        int retval = 0;
 
-        if (radio->disconnected)
-                return -EIO;
-        if (freq->type != V4L2_TUNER_RADIO)
-                return -EINVAL;
+        /* safety checks */
+        if (radio->disconnected) {
+                retval = -EIO;
+                goto done;
+        }
+        if ((freq->tuner != 0) && (freq->type != V4L2_TUNER_RADIO)) {
+                retval = -EINVAL;
+                goto done;
+        }
 
         retval = si470x_set_freq(radio, freq->frequency);
+
+done:
         if (retval < 0)
                 printk(KERN_WARNING DRIVER_NAME
                         ": set frequency failed with %d\n", retval);
-
-        return 0;
+        return retval;
 }
 
 
@@ -1428,33 +1528,36 @@ static int si470x_usb_driver_probe(struct usb_interface *intf,
                 const struct usb_device_id *id)
 {
         struct si470x_device *radio;
-        int retval = -ENOMEM;
+        int retval = 0;
 
-        /* private data allocation */
+        /* private data allocation and initialization */
         radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
-        if (!radio)
+        if (!radio) {
+                retval = -ENOMEM;
                 goto err_initial;
-
-        /* video device allocation */
-        radio->videodev = video_device_alloc();
-        if (!radio->videodev)
-                goto err_radio;
-
-        /* initial configuration */
-        memcpy(radio->videodev, &si470x_viddev_template,
-                        sizeof(si470x_viddev_template));
+        }
         radio->users = 0;
         radio->disconnected = 0;
         radio->usbdev = interface_to_usbdev(intf);
         radio->intf = intf;
         mutex_init(&radio->disconnect_lock);
         mutex_init(&radio->lock);
+
+        /* video device allocation and initialization */
+        radio->videodev = video_device_alloc();
+        if (!radio->videodev) {
+                retval = -ENOMEM;
+                goto err_radio;
+        }
+        memcpy(radio->videodev, &si470x_viddev_template,
+                        sizeof(si470x_viddev_template));
         video_set_drvdata(radio->videodev, radio);
 
         /* show some infos about the specific device */
-        retval = -EIO;
-        if (si470x_get_all_registers(radio) < 0)
+        if (si470x_get_all_registers(radio) < 0) {
+                retval = -EIO;
                 goto err_all;
+        }
         printk(KERN_INFO DRIVER_NAME ": DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
                         radio->registers[DEVICEID], radio->registers[CHIPID]);
 
@@ -1480,8 +1583,10 @@ static int si470x_usb_driver_probe(struct usb_interface *intf,
         /* rds buffer allocation */
         radio->buf_size = rds_buf * 3;
         radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
-        if (!radio->buffer)
+        if (!radio->buffer) {
+                retval = -EIO;
                 goto err_all;
+        }
 
         /* rds buffer configuration */
         radio->wr_index = 0;
@@ -1493,6 +1598,7 @@ static int si470x_usb_driver_probe(struct usb_interface *intf,
 
         /* register video device */
         if (video_register_device(radio->videodev, VFL_TYPE_RADIO, radio_nr)) {
+                retval = -EIO;
                 printk(KERN_WARNING DRIVER_NAME
                                 ": Could not register video device\n");
                 goto err_all;