/* Driver for SAA6588 RDS decoder (c) 2005 Hans J. Koch This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/i2c.h> #include <linux/types.h> #include <linux/videodev.h> #include <linux/init.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/poll.h> #include <linux/wait.h> #include <asm/uaccess.h> #include <media/rds.h> /* Addresses to scan */ static unsigned short normal_i2c[] = { 0x20 >> 1, 0x22 >> 1, I2C_CLIENT_END, }; I2C_CLIENT_INSMOD; /* insmod options */ static unsigned int debug; static unsigned int xtal; static unsigned int rbds; static unsigned int plvl; static unsigned int bufblocks = 100; module_param(debug, int, 0644); MODULE_PARM_DESC(debug, "enable debug messages"); module_param(xtal, int, 0); MODULE_PARM_DESC(xtal, "select oscillator frequency (0..3), default 0"); module_param(rbds, int, 0); MODULE_PARM_DESC(rbds, "select mode, 0=RDS, 1=RBDS, default 0"); module_param(plvl, int, 0); MODULE_PARM_DESC(plvl, "select pause level (0..3), default 0"); module_param(bufblocks, int, 0); MODULE_PARM_DESC(bufblocks, "number of buffered blocks, default 100"); MODULE_DESCRIPTION("v4l2 driver module for SAA6588 RDS decoder"); MODULE_AUTHOR("Hans J. Koch <koch@hjk-az.de>"); MODULE_LICENSE("GPL"); /* ---------------------------------------------------------------------- */ #define UNSET (-1U) #define PREFIX "saa6588: " #define dprintk if (debug) printk struct saa6588 { struct i2c_client client; struct work_struct work; struct timer_list timer; spinlock_t lock; unsigned char *buffer; 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; }; static struct i2c_driver driver; static struct i2c_client client_template; /* ---------------------------------------------------------------------- */ /* * SAA6588 defines */ /* Initialization and mode control byte (0w) */ /* bit 0+1 (DAC0/DAC1) */ #define cModeStandard 0x00 #define cModeFastPI 0x01 #define cModeReducedRequest 0x02 #define cModeInvalid 0x03 /* bit 2 (RBDS) */ #define cProcessingModeRDS 0x00 #define cProcessingModeRBDS 0x04 /* bit 3+4 (SYM0/SYM1) */ #define cErrCorrectionNone 0x00 #define cErrCorrection2Bits 0x08 #define cErrCorrection5Bits 0x10 #define cErrCorrectionNoneRBDS 0x18 /* bit 5 (NWSY) */ #define cSyncNormal 0x00 #define cSyncRestart 0x20 /* bit 6 (TSQD) */ #define cSigQualityDetectOFF 0x00 #define cSigQualityDetectON 0x40 /* bit 7 (SQCM) */ #define cSigQualityTriggered 0x00 #define cSigQualityContinous 0x80 /* Pause level and flywheel control byte (1w) */ /* bits 0..5 (FEB0..FEB5) */ #define cFlywheelMaxBlocksMask 0x3F #define cFlywheelDefault 0x20 /* bits 6+7 (PL0/PL1) */ #define cPauseLevel_11mV 0x00 #define cPauseLevel_17mV 0x40 #define cPauseLevel_27mV 0x80 #define cPauseLevel_43mV 0xC0 /* Pause time/oscillator frequency/quality detector control byte (1w) */ /* bits 0..4 (SQS0..SQS4) */ #define cQualityDetectSensMask 0x1F #define cQualityDetectDefault 0x0F /* bit 5 (SOSC) */ #define cSelectOscFreqOFF 0x00 #define cSelectOscFreqON 0x20 /* bit 6+7 (PTF0/PTF1) */ #define cOscFreq_4332kHz 0x00 #define cOscFreq_8664kHz 0x40 #define cOscFreq_12996kHz 0x80 #define cOscFreq_17328kHz 0xC0 /* ---------------------------------------------------------------------- */ static int block_to_user_buf(struct saa6588 *s, unsigned char __user *user_buf) { int i; if (s->rd_index == s->wr_index) { if (debug > 2) dprintk(PREFIX "Read: buffer empty.\n"); return 0; } if (debug > 2) { dprintk(PREFIX "Read: "); for (i = s->rd_index; i < s->rd_index + 3; i++) dprintk("0x%02x ", s->buffer[i]); } if (copy_to_user(user_buf, &s->buffer[s->rd_index], 3)) return -EFAULT; s->rd_index += 3; if (s->rd_index >= s->buf_size) s->rd_index = 0; s->block_count--; if (debug > 2) dprintk("%d blocks total.\n", s->block_count); return 1; } static void read_from_buf(struct saa6588 *s, struct rds_command *a) { unsigned long flags; unsigned char __user *buf_ptr = a->buffer; unsigned int i; unsigned int rd_blocks; a->result = 0; if (!a->buffer) return; while (!s->data_available_for_read) { int ret = wait_event_interruptible(s->read_queue, s->data_available_for_read); if (ret == -ERESTARTSYS) { a->result = -EINTR; return; } } spin_lock_irqsave(&s->lock, flags); rd_blocks = a->block_count; if (rd_blocks > s->block_count) rd_blocks = s->block_count; if (!rd_blocks) { spin_unlock_irqrestore(&s->lock, flags); return; } for (i = 0; i < rd_blocks; i++) { if (block_to_user_buf(s, buf_ptr)) { buf_ptr += 3; a->result++; } else break; } a->result *= 3; s->data_available_for_read = (s->block_count > 0); spin_unlock_irqrestore(&s->lock, flags); } static void block_to_buf(struct saa6588 *s, unsigned char *blockbuf) { unsigned int i; if (debug > 3) dprintk(PREFIX "New block: "); for (i = 0; i < 3; ++i) { if (debug > 3) dprintk("0x%02x ", blockbuf[i]); s->buffer[s->wr_index] = blockbuf[i]; s->wr_index++; } if (s->wr_index >= s->buf_size) s->wr_index = 0; if (s->wr_index == s->rd_index) { s->rd_index += 3; if (s->rd_index >= s->buf_size) s->rd_index = 0; } else s->block_count++; if (debug > 3) dprintk("%d blocks total.\n", s->block_count); } static void saa6588_i2c_poll(struct saa6588 *s) { unsigned long flags; unsigned char tmpbuf[6]; unsigned char blocknum; unsigned char tmp; /* Although we only need 3 bytes, we have to read at least 6. SAA6588 returns garbage otherwise */ if (6 != i2c_master_recv(&s->client, &tmpbuf[0], 6)) { if (debug > 1) dprintk(PREFIX "read error!\n"); return; } blocknum = tmpbuf[0] >> 5; if (blocknum == s->last_blocknum) { if (debug > 3) dprintk("Saw block %d again.\n", blocknum); return; } s->last_blocknum = blocknum; /* Byte order according to v4l2 specification: Byte 0: Least Significant Byte of RDS Block Byte 1: Most Significant Byte of RDS Block Byte 2 Bit 7: Error bit. Indicates that an uncorrectable error occurred during reception of this block. Bit 6: Corrected bit. Indicates that an error was corrected for this data block. Bits 5-3: Received Offset. Indicates the offset received by the sync system. Bits 2-0: Offset Name. Indicates the offset applied to this data. SAA6588 byte order is Status-MSB-LSB, so we have to swap the first and the last of the 3 bytes block. */ tmp = tmpbuf[2]; tmpbuf[2] = tmpbuf[0]; tmpbuf[0] = tmp; tmp = blocknum; tmp |= blocknum << 3; /* Received offset == Offset Name (OK ?) */ if ((tmpbuf[2] & 0x03) == 0x03) tmp |= 0x80; /* uncorrectable error */ else if ((tmpbuf[2] & 0x03) != 0x00) tmp |= 0x40; /* corrected error */ tmpbuf[2] = tmp; /* Is this enough ? Should we also check other bits ? */ spin_lock_irqsave(&s->lock, flags); block_to_buf(s, tmpbuf); spin_unlock_irqrestore(&s->lock, flags); s->data_available_for_read = 1; wake_up_interruptible(&s->read_queue); } static void saa6588_timer(unsigned long data) { struct saa6588 *s = (struct saa6588 *)data; schedule_work(&s->work); } static void saa6588_work(struct work_struct *work) { struct saa6588 *s = container_of(work, struct saa6588, work); saa6588_i2c_poll(s); mod_timer(&s->timer, jiffies + msecs_to_jiffies(20)); } static int saa6588_configure(struct saa6588 *s) { unsigned char buf[3]; int rc; buf[0] = cSyncRestart; if (rbds) buf[0] |= cProcessingModeRBDS; buf[1] = cFlywheelDefault; switch (plvl) { case 0: buf[1] |= cPauseLevel_11mV; break; case 1: buf[1] |= cPauseLevel_17mV; break; case 2: buf[1] |= cPauseLevel_27mV; break; case 3: buf[1] |= cPauseLevel_43mV; break; default: /* nothing */ break; } buf[2] = cQualityDetectDefault | cSelectOscFreqON; switch (xtal) { case 0: buf[2] |= cOscFreq_4332kHz; break; case 1: buf[2] |= cOscFreq_8664kHz; break; case 2: buf[2] |= cOscFreq_12996kHz; break; case 3: buf[2] |= cOscFreq_17328kHz; break; default: /* nothing */ break; } dprintk(PREFIX "writing: 0w=0x%02x 1w=0x%02x 2w=0x%02x\n", buf[0], buf[1], buf[2]); if (3 != (rc = i2c_master_send(&s->client, buf, 3))) printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc); return 0; } /* ---------------------------------------------------------------------- */ static int saa6588_attach(struct i2c_adapter *adap, int addr, int kind) { struct saa6588 *s; client_template.adapter = adap; client_template.addr = addr; printk(PREFIX "chip found @ 0x%x\n", addr << 1); if (NULL == (s = kmalloc(sizeof(*s), GFP_KERNEL))) return -ENOMEM; s->buf_size = bufblocks * 3; if (NULL == (s->buffer = kmalloc(s->buf_size, GFP_KERNEL))) { kfree(s); return -ENOMEM; } spin_lock_init(&s->lock); s->client = client_template; s->block_count = 0; s->wr_index = 0; s->rd_index = 0; s->last_blocknum = 0xff; init_waitqueue_head(&s->read_queue); s->data_available_for_read = 0; i2c_set_clientdata(&s->client, s); i2c_attach_client(&s->client); saa6588_configure(s); /* start polling via eventd */ INIT_WORK(&s->work, saa6588_work); init_timer(&s->timer); s->timer.function = saa6588_timer; s->timer.data = (unsigned long)s; schedule_work(&s->work); return 0; } static int saa6588_probe(struct i2c_adapter *adap) { if (adap->class & I2C_CLASS_TV_ANALOG) return i2c_probe(adap, &addr_data, saa6588_attach); return 0; } static int saa6588_detach(struct i2c_client *client) { struct saa6588 *s = i2c_get_clientdata(client); del_timer_sync(&s->timer); flush_scheduled_work(); i2c_detach_client(client); kfree(s->buffer); kfree(s); return 0; } static int saa6588_command(struct i2c_client *client, unsigned int cmd, void *arg) { struct saa6588 *s = i2c_get_clientdata(client); struct rds_command *a = (struct rds_command *)arg; switch (cmd) { /* --- open() for /dev/radio --- */ case RDS_CMD_OPEN: a->result = 0; /* return error if chip doesn't work ??? */ break; /* --- close() for /dev/radio --- */ case RDS_CMD_CLOSE: s->data_available_for_read = 1; wake_up_interruptible(&s->read_queue); a->result = 0; break; /* --- read() for /dev/radio --- */ case RDS_CMD_READ: read_from_buf(s, a); break; /* --- poll() for /dev/radio --- */ case RDS_CMD_POLL: a->result = 0; if (s->data_available_for_read) { a->result |= POLLIN | POLLRDNORM; } poll_wait(a->instance, &s->read_queue, a->event_list); break; default: /* nothing */ break; } return 0; } /* ----------------------------------------------------------------------- */ static struct i2c_driver driver = { .driver = { .name = "saa6588", }, .id = -1, /* FIXME */ .attach_adapter = saa6588_probe, .detach_client = saa6588_detach, .command = saa6588_command, }; static struct i2c_client client_template = { .name = "saa6588", .driver = &driver, }; static int __init saa6588_init_module(void) { return i2c_add_driver(&driver); } static void __exit saa6588_cleanup_module(void) { i2c_del_driver(&driver); } module_init(saa6588_init_module); module_exit(saa6588_cleanup_module); /* * Overrides for Emacs so that we follow Linus's tabbing style. * --------------------------------------------------------------------------- * Local variables: * c-basic-offset: 8 * End: */