]> err.no Git - linux-2.6/blobdiff - drivers/media/radio/radio-si470x.c
RDMA/cxgb3: Fix regression caused by class_device -> device conversion
[linux-2.6] / drivers / media / radio / radio-si470x.c
index d54fe6405351c51edf0d9dba2590318751cf3e53..77354ca6e8e928005cfcf631ed97d698bfd9b1ab 100644 (file)
  *             - applied all checkpatch.pl v1.12 suggestions
  *               except the warning about the too long lines with bit comments
  *             - renamed FMRADIO to RADIO to cut line length (checkpatch.pl)
+ * 2008-01-22  Tobias Lorenz <tobias.lorenz@gmx.net>
+ *             Version 1.0.4
+ *             - avoid poss. locking when doing copy_to_user which may sleep
+ *             - RDS is automatically activated on read now
+ *             - code cleaned of unnecessary rds_commands
+ *             - USB Vendor/Product ID for ADS/Tech FM Radio Receiver verified
+ *               (thanks to Guillaume RAMOUSSE)
+ * 2008-01-27  Tobias Lorenz <tobias.lorenz@gmx.net>
+ *             Version 1.0.5
+ *             - number of seek_retries changed to tune_timeout
+ *             - fixed problem with incomplete tune operations by own buffers
+ *             - optimization of variables and printf types
+ *             - improved error logging
+ * 2008-01-31  Tobias Lorenz <tobias.lorenz@gmx.net>
+ *             Oliver Neukum <oliver@neukum.org>
+ *             Version 1.0.6
+ *             - fixed coverity checker warnings in *_usb_driver_disconnect
+ *             - probe()/open() race by correct ordering in probe()
+ *             - DMA coherency rules by separate allocation of all buffers
+ *             - use of endianness macros
+ *             - abuse of spinlock, replaced by mutex
+ *             - racy handling of timer in disconnect,
+ *               replaced by delayed_work
+ *             - racy interruptible_sleep_on(),
+ *               replaced with wait_event_interruptible()
+ *             - handle signals in read()
+ * 2008-02-08  Tobias Lorenz <tobias.lorenz@gmx.net>
+ *             Oliver Neukum <oliver@neukum.org>
+ *             Version 1.0.7
+ *             - usb autosuspend support
+ *             - unplugging fixed
  *
  * ToDo:
- * - check USB Vendor/Product ID for ADS/Tech FM Radio Receiver
- *   (formerly Instant FM Music) (RDX-155-EF) is 06e1:a155
  * - add seeking support
  * - add firmware download/update support
- * - add possibility to switch off RDS
  * - RDS support: interrupt mode, instead of polling
  * - add LED status output (check if that's not already done in firmware)
  */
 /* driver definitions */
 #define DRIVER_AUTHOR "Tobias Lorenz <tobias.lorenz@gmx.net>"
 #define DRIVER_NAME "radio-si470x"
-#define DRIVER_VERSION KERNEL_VERSION(1, 0, 3)
+#define DRIVER_KERNEL_VERSION KERNEL_VERSION(1, 0, 7)
 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
 #define DRIVER_DESC "USB radio driver for Si470x FM Radio Receivers"
+#define DRIVER_VERSION "1.0.7"
 
 
 /* kernel includes */
 #include <linux/hid.h>
 #include <linux/version.h>
 #include <linux/videodev2.h>
+#include <linux/mutex.h>
 #include <media/v4l2-common.h>
 #include <media/rds.h>
+#include <asm/unaligned.h>
 
 
 /* USB Device ID List */
 static struct usb_device_id si470x_usb_driver_id_table[] = {
        /* Silicon Labs USB FM Radio Reference Design */
        { USB_DEVICE_AND_INTERFACE_INFO(0x10c4, 0x818a, USB_CLASS_HID, 0, 0) },
+       /* ADS/Tech FM Radio Receiver (formerly Instant FM Music) */
+       { USB_DEVICE_AND_INTERFACE_INFO(0x06e1, 0xa155, USB_CLASS_HID, 0, 0) },
        /* Terminating entry */
        { }
 };
@@ -113,55 +146,56 @@ MODULE_PARM_DESC(radio_nr, "Radio Nr");
 /* 0: 200 kHz (USA, Australia) */
 /* 1: 100 kHz (Europe, Japan) */
 /* 2:  50 kHz */
-static int space = 2;
-module_param(space, int, 0);
+static unsigned short space = 2;
+module_param(space, ushort, 0);
 MODULE_PARM_DESC(radio_nr, "Spacing: 0=200kHz 1=100kHz *2=50kHz*");
 
 /* Bottom of Band (MHz) */
 /* 0: 87.5 - 108 MHz (USA, Europe)*/
 /* 1: 76   - 108 MHz (Japan wide band) */
 /* 2: 76   -  90 MHz (Japan) */
-static int band = 1;
-module_param(band, int, 0);
+static unsigned short band = 1;
+module_param(band, ushort, 0);
 MODULE_PARM_DESC(radio_nr, "Band: 0=87.5..108MHz *1=76..108MHz* 2=76..90MHz");
 
 /* De-emphasis */
 /* 0: 75 us (USA) */
 /* 1: 50 us (Europe, Australia, Japan) */
-static int de = 1;
-module_param(de, int, 0);
+static unsigned short de = 1;
+module_param(de, ushort, 0);
 MODULE_PARM_DESC(radio_nr, "De-emphasis: 0=75us *1=50us*");
 
 /* USB timeout */
-static int usb_timeout = 500;
-module_param(usb_timeout, int, 0);
+static unsigned int usb_timeout = 500;
+module_param(usb_timeout, uint, 0);
 MODULE_PARM_DESC(usb_timeout, "USB timeout (ms): *500*");
 
-/* Seek retries */
-static int seek_retries = 100;
-module_param(seek_retries, int, 0);
-MODULE_PARM_DESC(seek_retries, "Seek retries: *100*");
+/* Tune timeout */
+static unsigned int tune_timeout = 3000;
+module_param(tune_timeout, uint, 0);
+MODULE_PARM_DESC(tune_timeout, "Tune timeout: *3000*");
 
 /* RDS buffer blocks */
-static int rds_buf = 100;
-module_param(rds_buf, int, 0);
+static unsigned int rds_buf = 100;
+module_param(rds_buf, uint, 0);
 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
 
 /* RDS maximum block errors */
-static int max_rds_errors = 1;
+static unsigned short max_rds_errors = 1;
 /* 0 means   0  errors requiring correction */
 /* 1 means 1-2  errors requiring correction (used by original USBRadio.exe) */
 /* 2 means 3-5  errors requiring correction */
 /* 3 means   6+ errors or errors in checkword, correction not possible */
-module_param(max_rds_errors, int, 0);
+module_param(max_rds_errors, ushort, 0);
 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
 
 /* RDS poll frequency */
-static int rds_poll_time = 40;
+static unsigned int rds_poll_time = 40;
 /* 40 is used by the original USBRadio.exe */
+/* 50 is used by radio-cadet */
 /* 75 should be okay */
 /* 80 is the usual RDS receive interval */
-module_param(rds_poll_time, int, 0);
+module_param(rds_poll_time, uint, 0);
 MODULE_PARM_DESC(rds_poll_time, "RDS poll time (ms): *40*");
 
 
@@ -386,32 +420,33 @@ MODULE_PARM_DESC(rds_poll_time, "RDS poll time (ms): *40*");
 struct si470x_device {
        /* reference to USB and video device */
        struct usb_device *usbdev;
+       struct usb_interface *intf;
        struct video_device *videodev;
 
-       /* are these really necessary ? */
-       int users;
-
-       /* report buffer (maximum 64 bytes) */
-       unsigned char buf[64];
+       /* driver management */
+       unsigned int users;
+       unsigned char disconnected;
 
        /* Silabs internal registers (0..15) */
        unsigned short registers[RADIO_REGISTER_NUM];
 
        /* RDS receive buffer */
-       struct work_struct work;
-       struct timer_list timer;
-       spinlock_t lock;                /* buffer locking */
-       unsigned char *buffer;
+       struct delayed_work work;
+       wait_queue_head_t read_queue;
+       struct mutex lock;              /* buffer locking */
+       unsigned char *buffer;          /* size is always multiple of three */
        unsigned int buf_size;
        unsigned int rd_index;
        unsigned int wr_index;
-       unsigned int block_count;
-       unsigned char last_blocknum;
-       wait_queue_head_t read_queue;
-       int data_available_for_read;
 };
 
 
+/*
+ * Lock to prevent kfree of data before all users have releases the device.
+ */
+static DEFINE_MUTEX(open_close_lock);
+
+
 /*
  * The frequency is set in units of 62.5 Hz when using V4L2_TUNER_CAP_LOW,
  * 62.5 kHz otherwise.
@@ -430,28 +465,46 @@ struct si470x_device {
 /*
  * si470x_get_report - receive a HID report
  */
-static int si470x_get_report(struct si470x_device *radio, int size)
+static int si470x_get_report(struct si470x_device *radio, void *buf, int size)
 {
-       return usb_control_msg(radio->usbdev,
+       unsigned char *report = (unsigned char *) buf;
+       int retval;
+
+       retval = usb_control_msg(radio->usbdev,
                usb_rcvctrlpipe(radio->usbdev, 0),
                HID_REQ_GET_REPORT,
                USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
-               radio->buf[0], 2,
-               radio->buf, size, usb_timeout);
+               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;
 }
 
 
 /*
  * si470x_set_report - send a HID report
  */
-static int si470x_set_report(struct si470x_device *radio, int size)
+static int si470x_set_report(struct si470x_device *radio, void *buf, int size)
 {
-       return usb_control_msg(radio->usbdev,
+       unsigned char *report = (unsigned char *) buf;
+       int retval;
+
+       retval = usb_control_msg(radio->usbdev,
                usb_sndctrlpipe(radio->usbdev, 0),
                HID_REQ_SET_REPORT,
                USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
-               radio->buf[0], 2,
-               radio->buf, size, usb_timeout);
+               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;
 }
 
 
@@ -460,13 +513,16 @@ static int si470x_set_report(struct si470x_device *radio, int size)
  */
 static int si470x_get_register(struct si470x_device *radio, int regnr)
 {
+       unsigned char buf[REGISTER_REPORT_SIZE];
        int retval;
 
-       radio->buf[0] = REGISTER_REPORT(regnr);
+       buf[0] = REGISTER_REPORT(regnr);
+
+       retval = si470x_get_report(radio, (void *) &buf, sizeof(buf));
 
-       retval = si470x_get_report(radio, REGISTER_REPORT_SIZE);
        if (retval >= 0)
-               radio->registers[regnr] = (radio->buf[1] << 8) | radio->buf[2];
+               radio->registers[regnr] = be16_to_cpu(get_unaligned(
+                       (unsigned short *) &buf[1]));
 
        return (retval < 0) ? -EINVAL : 0;
 }
@@ -477,13 +533,14 @@ static int si470x_get_register(struct si470x_device *radio, int regnr)
  */
 static int si470x_set_register(struct si470x_device *radio, int regnr)
 {
+       unsigned char buf[REGISTER_REPORT_SIZE];
        int retval;
 
-       radio->buf[0] = REGISTER_REPORT(regnr);
-       radio->buf[1] = (radio->registers[regnr] & 0xff00) >> 8;
-       radio->buf[2] = (radio->registers[regnr] & 0x00ff);
+       buf[0] = REGISTER_REPORT(regnr);
+       put_unaligned(cpu_to_be16(radio->registers[regnr]),
+               (unsigned short *) &buf[1]);
 
-       retval = si470x_set_report(radio, REGISTER_REPORT_SIZE);
+       retval = si470x_set_report(radio, (void *) &buf, sizeof(buf));
 
        return (retval < 0) ? -EINVAL : 0;
 }
@@ -494,18 +551,19 @@ static int si470x_set_register(struct si470x_device *radio, int regnr)
  */
 static int si470x_get_all_registers(struct si470x_device *radio)
 {
+       unsigned char buf[ENTIRE_REPORT_SIZE];
        int retval;
-       int regnr;
+       unsigned char regnr;
 
-       radio->buf[0] = ENTIRE_REPORT;
+       buf[0] = ENTIRE_REPORT;
 
-       retval = si470x_get_report(radio, ENTIRE_REPORT_SIZE);
+       retval = si470x_get_report(radio, (void *) &buf, sizeof(buf));
 
        if (retval >= 0)
                for (regnr = 0; regnr < RADIO_REGISTER_NUM; regnr++)
-                       radio->registers[regnr] =
-                       (radio->buf[regnr * RADIO_REGISTER_SIZE + 1] << 8) |
-                        radio->buf[regnr * RADIO_REGISTER_SIZE + 2];
+                       radio->registers[regnr] = be16_to_cpu(get_unaligned(
+                               (unsigned short *)
+                               &buf[regnr * RADIO_REGISTER_SIZE + 1]));
 
        return (retval < 0) ? -EINVAL : 0;
 }
@@ -516,21 +574,28 @@ static int si470x_get_all_registers(struct si470x_device *radio)
  */
 static int si470x_get_rds_registers(struct si470x_device *radio)
 {
+       unsigned char buf[RDS_REPORT_SIZE];
        int retval;
-       int regnr;
        int size;
+       unsigned char regnr;
 
-       radio->buf[0] = RDS_REPORT;
+       buf[0] = RDS_REPORT;
 
        retval = usb_interrupt_msg(radio->usbdev,
-               usb_rcvctrlpipe(radio->usbdev, 1),
-               radio->buf, RDS_REPORT_SIZE, &size, usb_timeout);
+               usb_rcvintpipe(radio->usbdev, 1),
+               (void *) &buf, sizeof(buf), &size, usb_timeout);
+       if (size != sizeof(buf))
+              printk(KERN_WARNING DRIVER_NAME ": si470x_get_rds_registers: "
+                       "return size differs: %d != %zu\n", size, sizeof(buf));
+       if (retval < 0)
+               printk(KERN_WARNING DRIVER_NAME ": si470x_get_rds_registers: "
+                       "usb_interrupt_msg returned %d\n", retval);
 
        if (retval >= 0)
                for (regnr = 0; regnr < RDS_REGISTER_NUM; regnr++)
                        radio->registers[STATUSRSSI + regnr] =
-                       (radio->buf[regnr * RADIO_REGISTER_SIZE + 1] << 8) |
-                        radio->buf[regnr * RADIO_REGISTER_SIZE + 2];
+                               be16_to_cpu(get_unaligned((unsigned short *)
+                               &buf[regnr * RADIO_REGISTER_SIZE + 1]));
 
        return (retval < 0) ? -EINVAL : 0;
 }
@@ -539,9 +604,11 @@ static int si470x_get_rds_registers(struct si470x_device *radio)
 /*
  * si470x_set_chan - set the channel
  */
-static int si470x_set_chan(struct si470x_device *radio, int chan)
+static int si470x_set_chan(struct si470x_device *radio, unsigned short chan)
 {
-       int retval, i;
+       int retval;
+       unsigned long timeout;
+       bool timed_out = 0;
 
        /* start tuning */
        radio->registers[CHANNEL] &= ~CHANNEL_CHAN;
@@ -551,16 +618,17 @@ static int si470x_set_chan(struct si470x_device *radio, int chan)
                return retval;
 
        /* wait till seek operation has completed */
-       i = 0;
+       timeout = jiffies + msecs_to_jiffies(tune_timeout);
        do {
                retval = si470x_get_register(radio, STATUSRSSI);
                if (retval < 0)
                        return retval;
-       } while ((radio->registers[STATUSRSSI] & STATUSRSSI_STC) &&
-               (++i < seek_retries));
-       if (i >= seek_retries)
+               timed_out = time_after(jiffies, timeout);
+       } while (((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0) &&
+               (!timed_out));
+       if (timed_out)
                printk(KERN_WARNING DRIVER_NAME
-                       ": seek does not finish after %d tries\n", i);
+                       ": seek does not finish after %u ms\n", tune_timeout);
 
        /* stop tuning */
        radio->registers[CHANNEL] &= ~CHANNEL_TUNE;
@@ -571,9 +639,10 @@ static int si470x_set_chan(struct si470x_device *radio, int chan)
 /*
  * si470x_get_freq - get the frequency
  */
-static int si470x_get_freq(struct si470x_device *radio)
+static unsigned int si470x_get_freq(struct si470x_device *radio)
 {
-       int spacing, band_bottom, chan, freq;
+       unsigned int spacing, band_bottom, freq;
+       unsigned short chan;
        int retval;
 
        /* Spacing (kHz) */
@@ -612,9 +681,10 @@ static int si470x_get_freq(struct si470x_device *radio)
 /*
  * si470x_set_freq - set the frequency
  */
-static int si470x_set_freq(struct si470x_device *radio, int freq)
+static int si470x_set_freq(struct si470x_device *radio, unsigned int freq)
 {
-       int spacing, band_bottom, chan;
+       unsigned int spacing, band_bottom;
+       unsigned short chan;
 
        /* Spacing (kHz) */
        switch (space) {
@@ -658,8 +728,7 @@ static int si470x_start(struct si470x_device *radio)
                return retval;
 
        /* sysconfig 1 */
-       radio->registers[SYSCONFIG1] =
-               SYSCONFIG1_DE | SYSCONFIG1_RDS;
+       radio->registers[SYSCONFIG1] = SYSCONFIG1_DE;
        retval = si470x_set_register(radio, SYSCONFIG1);
        if (retval < 0)
                return retval;
@@ -685,6 +754,14 @@ static int si470x_start(struct si470x_device *radio)
  */
 static int si470x_stop(struct si470x_device *radio)
 {
+       int retval;
+
+       /* sysconfig 1 */
+       radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_RDS;
+       retval = si470x_set_register(radio, SYSCONFIG1);
+       if (retval < 0)
+               return retval;
+
        /* powercfg */
        radio->registers[POWERCFG] &= ~POWERCFG_DMUTE;
        /* POWERCFG_ENABLE has to automatically go low */
@@ -693,6 +770,25 @@ static int si470x_stop(struct si470x_device *radio)
 }
 
 
+/*
+ * si470x_rds_on - switch on rds reception
+ */
+static int si470x_rds_on(struct si470x_device *radio)
+{
+       int retval;
+
+       /* sysconfig 1 */
+       mutex_lock(&radio->lock);
+       radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDS;
+       retval = si470x_set_register(radio, SYSCONFIG1);
+       if (retval < 0)
+               radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_RDS;
+       mutex_unlock(&radio->lock);
+
+       return retval;
+}
+
+
 
 /**************************************************************************
  * RDS Driver Functions
@@ -703,15 +799,12 @@ static int si470x_stop(struct si470x_device *radio)
  */
 static void si470x_rds(struct si470x_device *radio)
 {
-       unsigned long flags;
-       unsigned char tmpbuf[3];
        unsigned char blocknum;
-       unsigned char bler; /* RDS block errors */
+       unsigned short bler; /* rds block errors */
        unsigned short rds;
-       unsigned int i;
+       unsigned char tmpbuf[3];
 
-       if (radio->users == 0)
-               return;
+       /* get rds blocks */
        if (si470x_get_rds_registers(radio) < 0)
                return;
        if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0) {
@@ -723,6 +816,8 @@ static void si470x_rds(struct si470x_device *radio)
                return;
        }
 
+       /* copy all four RDS blocks to internal buffer */
+       mutex_lock(&radio->lock);
        for (blocknum = 0; blocknum < 4; blocknum++) {
                switch (blocknum) {
                default:
@@ -748,65 +843,53 @@ static void si470x_rds(struct si470x_device *radio)
                };
 
                /* Fill the V4L2 RDS buffer */
-               tmpbuf[0] = rds & 0x00ff;       /* LSB */
-               tmpbuf[1] = (rds & 0xff00) >> 8;/* MSB */
+               put_unaligned(cpu_to_le16(rds), (unsigned short *) &tmpbuf);
                tmpbuf[2] = blocknum;           /* offset name */
                tmpbuf[2] |= blocknum << 3;     /* received offset */
                if (bler > max_rds_errors)
-                       tmpbuf[2] |= 0x80;      /* uncorrectable errors */
+                       tmpbuf[2] |= 0x80; /* uncorrectable errors */
                else if (bler > 0)
-                       tmpbuf[2] |= 0x40;      /* corrected error(s) */
-
-               spin_lock_irqsave(&radio->lock, flags);
+                       tmpbuf[2] |= 0x40; /* corrected error(s) */
 
                /* copy RDS block to internal buffer */
-               for (i = 0; i < 3; i++) {
-                       radio->buffer[radio->wr_index] = tmpbuf[i];
-                       radio->wr_index++;
-               }
+               memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
+               radio->wr_index += 3;
 
+               /* wrap write pointer */
                if (radio->wr_index >= radio->buf_size)
                        radio->wr_index = 0;
 
+               /* check for overflow */
                if (radio->wr_index == radio->rd_index) {
+                       /* increment and wrap read pointer */
                        radio->rd_index += 3;
                        if (radio->rd_index >= radio->buf_size)
                                radio->rd_index = 0;
-               } else
-                       radio->block_count++;
-
-               spin_unlock_irqrestore(&radio->lock, flags);
+               }
        }
+       mutex_unlock(&radio->lock);
 
-       radio->data_available_for_read = 1;
-       wake_up_interruptible(&radio->read_queue);
-}
-
-
-/*
- * si470x_timer - rds timer function
- */
-static void si470x_timer(unsigned long data)
-{
-       struct si470x_device *radio = (struct si470x_device *) data;
-
-       schedule_work(&radio->work);
+       /* wake up read queue */
+       if (radio->wr_index != radio->rd_index)
+               wake_up_interruptible(&radio->read_queue);
 }
 
 
 /*
- * si470x_timer - rds work function
+ * si470x_work - rds work function
  */
 static void si470x_work(struct work_struct *work)
 {
        struct si470x_device *radio = container_of(work, struct si470x_device,
-               work);
+               work.work);
 
-       if (radio->users == 0)
+       if (radio->disconnected)
+              return;
+       if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
                return;
 
        si470x_rds(radio);
-       mod_timer(&radio->timer, jiffies + msecs_to_jiffies(rds_poll_time));
+       schedule_delayed_work(&radio->work, msecs_to_jiffies(rds_poll_time));
 }
 
 
@@ -822,53 +905,52 @@ static ssize_t si470x_fops_read(struct file *file, char __user *buf,
                size_t count, loff_t *ppos)
 {
        struct si470x_device *radio = video_get_drvdata(video_devdata(file));
-       struct rds_command cmd;
-       unsigned long flags;
-       unsigned int i;
-       unsigned int rd_blocks;
-
-       cmd.block_count = count / 3; /* each RDS block needs 3 bytes */
-       cmd.result = 0;
-       cmd.buffer = buf;
-       cmd.instance = file;
-
-       /* copy RDS block out of internal buffer */
-       while (!radio->data_available_for_read) {
+       int retval = 0;
+       unsigned int block_count = 0;
+
+       /* switch on rds reception */
+       if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0) {
+               si470x_rds_on(radio);
+               schedule_delayed_work(&radio->work,
+                       msecs_to_jiffies(rds_poll_time));
+       }
+
+       /* block if no new data available */
+       while (radio->wr_index == radio->rd_index) {
+               if (file->f_flags & O_NONBLOCK)
+                       return -EWOULDBLOCK;
                if (wait_event_interruptible(radio->read_queue,
-                                    radio->data_available_for_read) < 0)
+                       radio->wr_index != radio->rd_index) < 0)
                        return -EINTR;
        }
 
-       spin_lock_irqsave(&radio->lock, flags);
-       rd_blocks = cmd.block_count;
-       if (rd_blocks > radio->block_count)
-               rd_blocks = radio->block_count;
-
-       if (!rd_blocks) {
-               spin_unlock_irqrestore(&radio->lock, flags);
-               return cmd.result;
-       }
+       /* calculate block count from byte count */
+       count /= 3;
 
-       for (i = 0; i < rd_blocks; i++) {
-               /* copy RDS block to user buffer */
+       /* copy RDS block out of internal buffer and to user buffer */
+       mutex_lock(&radio->lock);
+       while (block_count < count) {
                if (radio->rd_index == radio->wr_index)
                        break;
 
+               /* always transfer rds complete blocks */
                if (copy_to_user(buf, &radio->buffer[radio->rd_index], 3))
+                       /* retval = -EFAULT; */
                        break;
 
+               /* increment and wrap read pointer */
                radio->rd_index += 3;
                if (radio->rd_index >= radio->buf_size)
                        radio->rd_index = 0;
-               radio->block_count--;
 
+               /* increment counters */
+               block_count++;
                buf += 3;
-               cmd.result += 3;
+               retval += 3;
        }
-       radio->data_available_for_read = (radio->block_count > 0);
-       spin_unlock_irqrestore(&radio->lock, flags);
+       mutex_unlock(&radio->lock);
 
-       return cmd.result;
+       return retval;
 }
 
 
@@ -879,14 +961,20 @@ 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;
 
-       retval = 0;
-       if (radio->data_available_for_read)
-               retval = POLLIN | POLLRDNORM;
+       /* switch on rds reception */
+       if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0) {
+               si470x_rds_on(radio);
+               schedule_delayed_work(&radio->work,
+                       msecs_to_jiffies(rds_poll_time));
+       }
+
        poll_wait(file, &radio->read_queue, pts);
 
-       return retval;
+       if (radio->rd_index != radio->wr_index)
+               return POLLIN | POLLRDNORM;
+
+       return 0;
 }
 
 
@@ -895,16 +983,22 @@ static unsigned int si470x_fops_poll(struct file *file,
  */
 static int si470x_fops_open(struct inode *inode, struct file *file)
 {
-       int retval;
        struct si470x_device *radio = video_get_drvdata(video_devdata(file));
+       int retval;
 
        radio->users++;
+
+       retval = usb_autopm_get_interface(radio->intf);
+       if (retval < 0) {
+               radio->users--;
+               return -EIO;
+       }
+
        if (radio->users == 1) {
                retval = si470x_start(radio);
                if (retval < 0)
-                       return retval;
-
-               schedule_work(&radio->work);
+                       usb_autopm_put_interface(radio->intf);
+               return retval;
        }
 
        return 0;
@@ -916,23 +1010,35 @@ static int si470x_fops_open(struct inode *inode, struct file *file)
  */
 static int si470x_fops_release(struct inode *inode, struct file *file)
 {
-       int retval;
        struct si470x_device *radio = video_get_drvdata(video_devdata(file));
+       int retval = 0;
 
        if (!radio)
                return -ENODEV;
 
+       mutex_lock(&open_close_lock);
        radio->users--;
        if (radio->users == 0) {
-               radio->data_available_for_read = 1;             /* ? */
-               wake_up_interruptible(&radio->read_queue);      /* ? */
+              if (radio->disconnected) {
+                      video_unregister_device(radio->videodev);
+                      kfree(radio->buffer);
+                      kfree(radio);
+                      goto done;
+              }
+
+               /* stop rds reception */
+               cancel_delayed_work_sync(&radio->work);
+
+               /* cancel read processes */
+               wake_up_interruptible(&radio->read_queue);
 
                retval = si470x_stop(radio);
-               if (retval < 0)
-                       return retval;
+               usb_autopm_put_interface(radio->intf);
        }
 
-       return 0;
+done:
+       mutex_unlock(&open_close_lock);
+       return retval;
 }
 
 
@@ -945,7 +1051,9 @@ static const struct file_operations si470x_fops = {
        .read           = si470x_fops_read,
        .poll           = si470x_fops_poll,
        .ioctl          = video_ioctl2,
+#ifdef CONFIG_COMPAT
        .compat_ioctl   = v4l_compat_ioctl32,
+#endif
        .open           = si470x_fops_open,
        .release        = si470x_fops_release,
 };
@@ -1007,7 +1115,7 @@ static int si470x_vidioc_querycap(struct file *file, void *priv,
        strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
        strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
        sprintf(capability->bus_info, "USB");
-       capability->version = DRIVER_VERSION;
+       capability->version = DRIVER_KERNEL_VERSION;
        capability->capabilities = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
 
        return 0;
@@ -1044,16 +1152,21 @@ static int si470x_vidioc_s_input(struct file *filp, void *priv, unsigned int i)
 static int si470x_vidioc_queryctrl(struct file *file, void *priv,
                struct v4l2_queryctrl *qc)
 {
-       int i;
+       unsigned char i;
+       int retval = -EINVAL;
 
        for (i = 0; i < ARRAY_SIZE(si470x_v4l2_queryctrl); i++) {
                if (qc->id && qc->id == si470x_v4l2_queryctrl[i].id) {
                        memcpy(qc, &(si470x_v4l2_queryctrl[i]), sizeof(*qc));
-                       return 0;
+                       retval = 0;
+                       break;
                }
        }
+       if (retval < 0)
+               printk(KERN_WARNING DRIVER_NAME
+                       ": query control failed with %d\n", retval);
 
-       return -EINVAL;
+       return retval;
 }
 
 
@@ -1065,6 +1178,9 @@ static int si470x_vidioc_g_ctrl(struct file *file, void *priv,
 {
        struct si470x_device *radio = video_get_drvdata(video_devdata(file));
 
+       if (radio->disconnected)
+              return -EIO;
+
        switch (ctrl->id) {
        case V4L2_CID_AUDIO_VOLUME:
                ctrl->value = radio->registers[SYSCONFIG2] &
@@ -1087,21 +1203,32 @@ 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;
+
+       if (radio->disconnected)
+              return -EIO;
 
        switch (ctrl->id) {
        case V4L2_CID_AUDIO_VOLUME:
                radio->registers[SYSCONFIG2] &= ~SYSCONFIG2_VOLUME;
                radio->registers[SYSCONFIG2] |= ctrl->value;
-               return si470x_set_register(radio, SYSCONFIG2);
+               retval = si470x_set_register(radio, SYSCONFIG2);
+               break;
        case V4L2_CID_AUDIO_MUTE:
                if (ctrl->value == 1)
                        radio->registers[POWERCFG] &= ~POWERCFG_DMUTE;
                else
                        radio->registers[POWERCFG] |= POWERCFG_DMUTE;
-               return si470x_set_register(radio, POWERCFG);
+               retval = si470x_set_register(radio, POWERCFG);
+               break;
+       default:
+               retval = -EINVAL;
        }
+       if (retval < 0)
+               printk(KERN_WARNING DRIVER_NAME
+                       ": set control failed with %d\n", retval);
 
-       return -EINVAL;
+       return retval;
 }
 
 
@@ -1140,9 +1267,11 @@ static int si470x_vidioc_s_audio(struct file *file, void *priv,
 static int si470x_vidioc_g_tuner(struct file *file, void *priv,
                struct v4l2_tuner *tuner)
 {
-       int retval;
        struct si470x_device *radio = video_get_drvdata(video_devdata(file));
+       int retval;
 
+       if (radio->disconnected)
+              return -EIO;
        if (tuner->index > 0)
                return -EINVAL;
 
@@ -1197,7 +1326,10 @@ 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;
 
+       if (radio->disconnected)
+              return -EIO;
        if (tuner->index > 0)
                return -EINVAL;
 
@@ -1206,7 +1338,12 @@ static int si470x_vidioc_s_tuner(struct file *file, void *priv,
        else
                radio->registers[POWERCFG] &= ~POWERCFG_MONO; /* try stereo */
 
-       return si470x_set_register(radio, POWERCFG);
+       retval = si470x_set_register(radio, POWERCFG);
+       if (retval < 0)
+               printk(KERN_WARNING DRIVER_NAME
+                       ": set tuner failed with %d\n", retval);
+
+       return retval;
 }
 
 
@@ -1218,6 +1355,9 @@ static int si470x_vidioc_g_frequency(struct file *file, void *priv,
 {
        struct si470x_device *radio = video_get_drvdata(video_devdata(file));
 
+       if (radio->disconnected)
+              return -EIO;
+
        freq->type = V4L2_TUNER_RADIO;
        freq->frequency = si470x_get_freq(radio);
 
@@ -1232,11 +1372,19 @@ 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;
 
+       if (radio->disconnected)
+              return -EIO;
        if (freq->type != V4L2_TUNER_RADIO)
                return -EINVAL;
 
-       return si470x_set_freq(radio, freq->frequency);
+       retval = si470x_set_freq(radio, freq->frequency);
+       if (retval < 0)
+               printk(KERN_WARNING DRIVER_NAME
+                       ": set frequency failed with %d\n", retval);
+
+       return 0;
 }
 
 
@@ -1276,73 +1424,116 @@ static int si470x_usb_driver_probe(struct usb_interface *intf,
                const struct usb_device_id *id)
 {
        struct si470x_device *radio;
+       int retval = -ENOMEM;
 
-       /* memory and interface allocations */
-       radio = kmalloc(sizeof(struct si470x_device), GFP_KERNEL);
+       /* private data allocation */
+       radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
        if (!radio)
-               return -ENOMEM;
+               goto err_initial;
+
+       /* video device allocation */
        radio->videodev = video_device_alloc();
-       if (!radio->videodev) {
-               kfree(radio);
-               return -ENOMEM;
-       }
+       if (!radio->videodev)
+               goto err_radio;
+
+       /* initial configuration */
        memcpy(radio->videodev, &si470x_viddev_template,
                        sizeof(si470x_viddev_template));
        radio->users = 0;
        radio->usbdev = interface_to_usbdev(intf);
+       radio->intf = intf;
+       mutex_init(&radio->lock);
        video_set_drvdata(radio->videodev, radio);
-       if (video_register_device(radio->videodev, VFL_TYPE_RADIO, radio_nr)) {
-               printk(KERN_WARNING DRIVER_NAME
-                               ": Could not register video device\n");
-               video_device_release(radio->videodev);
-               kfree(radio);
-               return -EIO;
-       }
-       usb_set_intfdata(intf, radio);
 
        /* show some infos about the specific device */
-       if (si470x_get_all_registers(radio) < 0) {
-               video_device_release(radio->videodev);
-               kfree(radio);
-               return -EIO;
-       }
-       printk(KERN_INFO DRIVER_NAME ": DeviceID=0x%4.4x ChipID=0x%4.4x\n",
+       retval = -EIO;
+       if (si470x_get_all_registers(radio) < 0)
+               goto err_all;
+       printk(KERN_INFO DRIVER_NAME ": DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
                        radio->registers[DEVICEID], radio->registers[CHIPID]);
 
        /* check if firmware is current */
        if ((radio->registers[CHIPID] & CHIPID_FIRMWARE)
-                       < RADIO_SW_VERSION_CURRENT)
+                       < RADIO_SW_VERSION_CURRENT) {
+               printk(KERN_WARNING DRIVER_NAME
+                       ": This driver is known to work with "
+                       "firmware version %hu,\n", RADIO_SW_VERSION_CURRENT);
+               printk(KERN_WARNING DRIVER_NAME
+                       ": but the device has firmware version %hu.\n",
+                       radio->registers[CHIPID] & CHIPID_FIRMWARE);
                printk(KERN_WARNING DRIVER_NAME
-                       ": This driver is known to work with chip version %d, "
-                       "but the device has firmware %d. If you have some "
-                       "trouble using this driver, please report to V4L ML "
-                       "at video4linux-list@redhat.com\n",
-                       radio->registers[CHIPID] & CHIPID_FIRMWARE,
-                       RADIO_SW_VERSION_CURRENT);
+                       ": If you have some trouble using this driver,\n");
+               printk(KERN_WARNING DRIVER_NAME
+                       ": please report to V4L ML at "
+                       "video4linux-list@redhat.com\n");
+       }
 
        /* set initial frequency */
        si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
 
-       /* rds initialization */
+       /* rds buffer allocation */
        radio->buf_size = rds_buf * 3;
        radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
-       if (!radio->buffer) {
-               video_device_release(radio->videodev);
-               kfree(radio);
-               return -ENOMEM;
-       }
-       radio->block_count = 0;
+       if (!radio->buffer)
+               goto err_all;
+
+       /* rds buffer configuration */
        radio->wr_index = 0;
        radio->rd_index = 0;
-       radio->last_blocknum = 0xff;
        init_waitqueue_head(&radio->read_queue);
-       radio->data_available_for_read = 0;
 
-       /* prepare polling via eventd */
-       INIT_WORK(&radio->work, si470x_work);
-       init_timer(&radio->timer);
-       radio->timer.function = si470x_timer;
-       radio->timer.data = (unsigned long) radio;
+       /* prepare rds work function */
+       INIT_DELAYED_WORK(&radio->work, si470x_work);
+
+       /* register video device */
+       if (video_register_device(radio->videodev, VFL_TYPE_RADIO, radio_nr)) {
+               printk(KERN_WARNING DRIVER_NAME
+                               ": Could not register video device\n");
+               goto err_all;
+       }
+       usb_set_intfdata(intf, radio);
+
+       return 0;
+err_all:
+       video_device_release(radio->videodev);
+       kfree(radio->buffer);
+err_radio:
+       kfree(radio);
+err_initial:
+       return retval;
+}
+
+
+/*
+ * si470x_usb_driver_suspend - suspend the device
+ */
+static int si470x_usb_driver_suspend(struct usb_interface *intf,
+               pm_message_t message)
+{
+       struct si470x_device *radio = usb_get_intfdata(intf);
+
+       printk(KERN_INFO DRIVER_NAME ": suspending now...\n");
+
+       cancel_delayed_work_sync(&radio->work);
+
+       return 0;
+}
+
+
+/*
+ * si470x_usb_driver_resume - resume the device
+ */
+static int si470x_usb_driver_resume(struct usb_interface *intf)
+{
+       struct si470x_device *radio = usb_get_intfdata(intf);
+
+       printk(KERN_INFO DRIVER_NAME ": resuming now...\n");
+
+       mutex_lock(&radio->lock);
+       if (radio->users && radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS)
+               schedule_delayed_work(&radio->work,
+                       msecs_to_jiffies(rds_poll_time));
+       mutex_unlock(&radio->lock);
 
        return 0;
 }
@@ -1355,15 +1546,16 @@ static void si470x_usb_driver_disconnect(struct usb_interface *intf)
 {
        struct si470x_device *radio = usb_get_intfdata(intf);
 
-       del_timer_sync(&radio->timer);
-       flush_scheduled_work();
-
+       mutex_lock(&open_close_lock);
+       radio->disconnected = 1;
+       cancel_delayed_work_sync(&radio->work);
        usb_set_intfdata(intf, NULL);
-       if (radio) {
-               video_unregister_device(radio->videodev);
-               kfree(radio->buffer);
-               kfree(radio);
-       }
+       if (radio->users == 0) {
+              video_unregister_device(radio->videodev);
+              kfree(radio->buffer);
+              kfree(radio);
+       }
+       mutex_unlock(&open_close_lock);
 }
 
 
@@ -1371,10 +1563,13 @@ static void si470x_usb_driver_disconnect(struct usb_interface *intf)
  * si470x_usb_driver - usb driver interface
  */
 static struct usb_driver si470x_usb_driver = {
-       .name           = DRIVER_NAME,
-       .probe          = si470x_usb_driver_probe,
-       .disconnect     = si470x_usb_driver_disconnect,
-       .id_table       = si470x_usb_driver_id_table,
+       .name                   = DRIVER_NAME,
+       .probe                  = si470x_usb_driver_probe,
+       .disconnect             = si470x_usb_driver_disconnect,
+       .suspend                = si470x_usb_driver_suspend,
+       .resume                 = si470x_usb_driver_resume,
+       .id_table               = si470x_usb_driver_id_table,
+       .supports_autosuspend   = 1,
 };
 
 
@@ -1388,7 +1583,7 @@ static struct usb_driver si470x_usb_driver = {
  */
 static int __init si470x_module_init(void)
 {
-       printk(KERN_INFO DRIVER_DESC "\n");
+       printk(KERN_INFO DRIVER_DESC ", Version " DRIVER_VERSION "\n");
        return usb_register(&si470x_usb_driver);
 }
 
@@ -1408,4 +1603,4 @@ module_exit(si470x_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
-MODULE_VERSION("1.0.3");
+MODULE_VERSION(DRIVER_VERSION);