diff options
Diffstat (limited to 'drivers/media/i2c/saa6588.c')
-rw-r--r-- | drivers/media/i2c/saa6588.c | 514 |
1 files changed, 514 insertions, 0 deletions
diff --git a/drivers/media/i2c/saa6588.c b/drivers/media/i2c/saa6588.c new file mode 100644 index 000000000..d6a51beab --- /dev/null +++ b/drivers/media/i2c/saa6588.c @@ -0,0 +1,514 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Driver for SAA6588 RDS decoder + + (c) 2005 Hans J. Koch + +*/ + + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/i2c.h> +#include <linux/types.h> +#include <linux/videodev2.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/poll.h> +#include <linux/wait.h> +#include <linux/uaccess.h> + +#include <media/i2c/saa6588.h> +#include <media/v4l2-device.h> + + +/* insmod options */ +static unsigned int debug; +static unsigned int xtal; +static unsigned int mmbs; +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(mmbs, int, 0); +MODULE_PARM_DESC(mmbs, "enable MMBS mode: 0=off (default), 1=on"); +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 v4l2_subdev sd; + struct delayed_work work; + 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; + u8 sync; +}; + +static inline struct saa6588 *to_saa6588(struct v4l2_subdev *sd) +{ + return container_of(sd, struct saa6588, sd); +} + +/* ---------------------------------------------------------------------- */ + +/* + * 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 bool block_from_buf(struct saa6588 *s, unsigned char *buf) +{ + int i; + + if (s->rd_index == s->wr_index) { + if (debug > 2) + dprintk(PREFIX "Read: buffer empty.\n"); + return false; + } + + if (debug > 2) { + dprintk(PREFIX "Read: "); + for (i = s->rd_index; i < s->rd_index + 3; i++) + dprintk("0x%02x ", s->buffer[i]); + } + + memcpy(buf, &s->buffer[s->rd_index], 3); + + 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 true; +} + +static void read_from_buf(struct saa6588 *s, struct saa6588_command *a) +{ + unsigned char __user *buf_ptr = a->buffer; + unsigned char buf[3]; + unsigned long flags; + unsigned int rd_blocks; + unsigned int i; + + a->result = 0; + if (!a->buffer) + return; + + while (!a->nonblocking && !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; + } + } + + rd_blocks = a->block_count; + spin_lock_irqsave(&s->lock, flags); + if (rd_blocks > s->block_count) + rd_blocks = s->block_count; + spin_unlock_irqrestore(&s->lock, flags); + + if (!rd_blocks) + return; + + for (i = 0; i < rd_blocks; i++) { + bool got_block; + + spin_lock_irqsave(&s->lock, flags); + got_block = block_from_buf(s, buf); + spin_unlock_irqrestore(&s->lock, flags); + if (!got_block) + break; + if (copy_to_user(buf_ptr, buf, 3)) { + a->result = -EFAULT; + return; + } + buf_ptr += 3; + a->result += 3; + } + spin_lock_irqsave(&s->lock, flags); + 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) +{ + struct i2c_client *client = v4l2_get_subdevdata(&s->sd); + 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(client, &tmpbuf[0], 6)) { + if (debug > 1) + dprintk(PREFIX "read error!\n"); + return; + } + + s->sync = tmpbuf[0] & 0x10; + if (!s->sync) + 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: Same as bits 0-2. + Bits 2-0: Block number. + + SAA6588 byte order is Status-MSB-LSB, so we have to swap the + first and the last of the 3 bytes block. + */ + + swap(tmpbuf[2], tmpbuf[0]); + + /* Map 'Invalid block E' to 'Invalid Block' */ + if (blocknum == 6) + blocknum = V4L2_RDS_BLOCK_INVALID; + /* And if are not in mmbs mode, then 'Block E' is also mapped + to 'Invalid Block'. As far as I can tell MMBS is discontinued, + and if there is ever a need to support E blocks, then please + contact the linux-media mailinglist. */ + else if (!mmbs && blocknum == 5) + blocknum = V4L2_RDS_BLOCK_INVALID; + tmp = blocknum; + tmp |= blocknum << 3; /* Received offset == Offset Name (OK ?) */ + if ((tmpbuf[2] & 0x03) == 0x03) + tmp |= V4L2_RDS_BLOCK_ERROR; /* uncorrectable error */ + else if ((tmpbuf[2] & 0x03) != 0x00) + tmp |= V4L2_RDS_BLOCK_CORRECTED; /* 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_work(struct work_struct *work) +{ + struct saa6588 *s = container_of(work, struct saa6588, work.work); + + saa6588_i2c_poll(s); + schedule_delayed_work(&s->work, msecs_to_jiffies(20)); +} + +static void saa6588_configure(struct saa6588 *s) +{ + struct i2c_client *client = v4l2_get_subdevdata(&s->sd); + unsigned char buf[3]; + int rc; + + buf[0] = cSyncRestart; + if (mmbs) + 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]); + + rc = i2c_master_send(client, buf, 3); + if (rc != 3) + printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc); +} + +/* ---------------------------------------------------------------------- */ + +static long saa6588_command(struct v4l2_subdev *sd, unsigned int cmd, void *arg) +{ + struct saa6588 *s = to_saa6588(sd); + struct saa6588_command *a = arg; + + switch (cmd) { + /* --- close() for /dev/radio --- */ + case SAA6588_CMD_CLOSE: + s->data_available_for_read = 1; + wake_up_interruptible(&s->read_queue); + s->data_available_for_read = 0; + a->result = 0; + break; + /* --- read() for /dev/radio --- */ + case SAA6588_CMD_READ: + read_from_buf(s, a); + break; + /* --- poll() for /dev/radio --- */ + case SAA6588_CMD_POLL: + a->poll_mask = 0; + if (s->data_available_for_read) + a->poll_mask |= EPOLLIN | EPOLLRDNORM; + poll_wait(a->instance, &s->read_queue, a->event_list); + break; + + default: + /* nothing */ + return -ENOIOCTLCMD; + } + return 0; +} + +static int saa6588_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt) +{ + struct saa6588 *s = to_saa6588(sd); + + vt->capability |= V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO; + if (s->sync) + vt->rxsubchans |= V4L2_TUNER_SUB_RDS; + return 0; +} + +static int saa6588_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *vt) +{ + struct saa6588 *s = to_saa6588(sd); + + saa6588_configure(s); + return 0; +} + +/* ----------------------------------------------------------------------- */ + +static const struct v4l2_subdev_core_ops saa6588_core_ops = { + .command = saa6588_command, +}; + +static const struct v4l2_subdev_tuner_ops saa6588_tuner_ops = { + .g_tuner = saa6588_g_tuner, + .s_tuner = saa6588_s_tuner, +}; + +static const struct v4l2_subdev_ops saa6588_ops = { + .core = &saa6588_core_ops, + .tuner = &saa6588_tuner_ops, +}; + +/* ---------------------------------------------------------------------- */ + +static int saa6588_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct saa6588 *s; + struct v4l2_subdev *sd; + + v4l_info(client, "saa6588 found @ 0x%x (%s)\n", + client->addr << 1, client->adapter->name); + + s = devm_kzalloc(&client->dev, sizeof(*s), GFP_KERNEL); + if (s == NULL) + return -ENOMEM; + + s->buf_size = bufblocks * 3; + + s->buffer = devm_kzalloc(&client->dev, s->buf_size, GFP_KERNEL); + if (s->buffer == NULL) + return -ENOMEM; + sd = &s->sd; + v4l2_i2c_subdev_init(sd, client, &saa6588_ops); + spin_lock_init(&s->lock); + 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; + + saa6588_configure(s); + + /* start polling via eventd */ + INIT_DELAYED_WORK(&s->work, saa6588_work); + schedule_delayed_work(&s->work, 0); + return 0; +} + +static void saa6588_remove(struct i2c_client *client) +{ + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct saa6588 *s = to_saa6588(sd); + + v4l2_device_unregister_subdev(sd); + + cancel_delayed_work_sync(&s->work); +} + +/* ----------------------------------------------------------------------- */ + +static const struct i2c_device_id saa6588_id[] = { + { "saa6588", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, saa6588_id); + +static struct i2c_driver saa6588_driver = { + .driver = { + .name = "saa6588", + }, + .probe = saa6588_probe, + .remove = saa6588_remove, + .id_table = saa6588_id, +}; + +module_i2c_driver(saa6588_driver); |