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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/media/radio/si470x/radio-si470x-i2c.c
Initial import
Diffstat (limited to 'drivers/media/radio/si470x/radio-si470x-i2c.c')
-rw-r--r--drivers/media/radio/si470x/radio-si470x-i2c.c526
1 files changed, 526 insertions, 0 deletions
diff --git a/drivers/media/radio/si470x/radio-si470x-i2c.c b/drivers/media/radio/si470x/radio-si470x-i2c.c
new file mode 100644
index 000000000..2a497c80c
--- /dev/null
+++ b/drivers/media/radio/si470x/radio-si470x-i2c.c
@@ -0,0 +1,526 @@
+/*
+ * drivers/media/radio/si470x/radio-si470x-i2c.c
+ *
+ * I2C driver for radios with Silicon Labs Si470x FM Radio Receivers
+ *
+ * Copyright (c) 2009 Samsung Electronics Co.Ltd
+ * Author: Joonyoung Shim <jy0922.shim@samsung.com>
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+
+/* driver definitions */
+#define DRIVER_AUTHOR "Joonyoung Shim <jy0922.shim@samsung.com>";
+#define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
+#define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
+#define DRIVER_VERSION "1.0.2"
+
+/* kernel includes */
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include "radio-si470x.h"
+
+
+/* I2C Device ID List */
+static const struct i2c_device_id si470x_i2c_id[] = {
+ /* Generic Entry */
+ { "si470x", 0 },
+ /* Terminating entry */
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
+
+
+
+/**************************************************************************
+ * Module Parameters
+ **************************************************************************/
+
+/* Radio Nr */
+static int radio_nr = -1;
+module_param(radio_nr, int, 0444);
+MODULE_PARM_DESC(radio_nr, "Radio Nr");
+
+/* RDS buffer blocks */
+static unsigned int rds_buf = 100;
+module_param(rds_buf, uint, 0444);
+MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
+
+/* RDS maximum block errors */
+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, ushort, 0644);
+MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
+
+
+
+/**************************************************************************
+ * I2C Definitions
+ **************************************************************************/
+
+/* Write starts with the upper byte of register 0x02 */
+#define WRITE_REG_NUM 8
+#define WRITE_INDEX(i) (i + 0x02)
+
+/* Read starts with the upper byte of register 0x0a */
+#define READ_REG_NUM RADIO_REGISTER_NUM
+#define READ_INDEX(i) ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
+
+
+
+/**************************************************************************
+ * General Driver Functions - REGISTERs
+ **************************************************************************/
+
+/*
+ * si470x_get_register - read register
+ */
+int si470x_get_register(struct si470x_device *radio, int regnr)
+{
+ u16 buf[READ_REG_NUM];
+ struct i2c_msg msgs[1] = {
+ {
+ .addr = radio->client->addr,
+ .flags = I2C_M_RD,
+ .len = sizeof(u16) * READ_REG_NUM,
+ .buf = (void *)buf
+ },
+ };
+
+ if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
+ return -EIO;
+
+ radio->registers[regnr] = __be16_to_cpu(buf[READ_INDEX(regnr)]);
+
+ return 0;
+}
+
+
+/*
+ * si470x_set_register - write register
+ */
+int si470x_set_register(struct si470x_device *radio, int regnr)
+{
+ int i;
+ u16 buf[WRITE_REG_NUM];
+ struct i2c_msg msgs[1] = {
+ {
+ .addr = radio->client->addr,
+ .len = sizeof(u16) * WRITE_REG_NUM,
+ .buf = (void *)buf
+ },
+ };
+
+ for (i = 0; i < WRITE_REG_NUM; i++)
+ buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
+
+ if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
+ return -EIO;
+
+ return 0;
+}
+
+
+
+/**************************************************************************
+ * General Driver Functions - ENTIRE REGISTERS
+ **************************************************************************/
+
+/*
+ * si470x_get_all_registers - read entire registers
+ */
+static int si470x_get_all_registers(struct si470x_device *radio)
+{
+ int i;
+ u16 buf[READ_REG_NUM];
+ struct i2c_msg msgs[1] = {
+ {
+ .addr = radio->client->addr,
+ .flags = I2C_M_RD,
+ .len = sizeof(u16) * READ_REG_NUM,
+ .buf = (void *)buf
+ },
+ };
+
+ if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
+ return -EIO;
+
+ for (i = 0; i < READ_REG_NUM; i++)
+ radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
+
+ return 0;
+}
+
+
+
+/**************************************************************************
+ * File Operations Interface
+ **************************************************************************/
+
+/*
+ * si470x_fops_open - file open
+ */
+int si470x_fops_open(struct file *file)
+{
+ struct si470x_device *radio = video_drvdata(file);
+ int retval = v4l2_fh_open(file);
+
+ if (retval)
+ return retval;
+
+ if (v4l2_fh_is_singular_file(file)) {
+ /* start radio */
+ retval = si470x_start(radio);
+ if (retval < 0)
+ goto done;
+
+ /* enable RDS / STC interrupt */
+ radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
+ radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
+ radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
+ radio->registers[SYSCONFIG1] |= 0x1 << 2;
+ retval = si470x_set_register(radio, SYSCONFIG1);
+ }
+
+done:
+ if (retval)
+ v4l2_fh_release(file);
+ return retval;
+}
+
+
+/*
+ * si470x_fops_release - file release
+ */
+int si470x_fops_release(struct file *file)
+{
+ struct si470x_device *radio = video_drvdata(file);
+
+ if (v4l2_fh_is_singular_file(file))
+ /* stop radio */
+ si470x_stop(radio);
+
+ return v4l2_fh_release(file);
+}
+
+
+
+/**************************************************************************
+ * Video4Linux Interface
+ **************************************************************************/
+
+/*
+ * si470x_vidioc_querycap - query device capabilities
+ */
+int si470x_vidioc_querycap(struct file *file, void *priv,
+ struct v4l2_capability *capability)
+{
+ strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
+ strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
+ capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE |
+ V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
+ capability->capabilities = capability->device_caps | V4L2_CAP_DEVICE_CAPS;
+
+ return 0;
+}
+
+
+
+/**************************************************************************
+ * I2C Interface
+ **************************************************************************/
+
+/*
+ * si470x_i2c_interrupt - interrupt handler
+ */
+static irqreturn_t si470x_i2c_interrupt(int irq, void *dev_id)
+{
+ struct si470x_device *radio = dev_id;
+ unsigned char regnr;
+ unsigned char blocknum;
+ unsigned short bler; /* rds block errors */
+ unsigned short rds;
+ unsigned char tmpbuf[3];
+ int retval = 0;
+
+ /* check Seek/Tune Complete */
+ retval = si470x_get_register(radio, STATUSRSSI);
+ if (retval < 0)
+ goto end;
+
+ if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
+ complete(&radio->completion);
+
+ /* safety checks */
+ if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
+ goto end;
+
+ /* Update RDS registers */
+ for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++) {
+ retval = si470x_get_register(radio, STATUSRSSI + regnr);
+ if (retval < 0)
+ goto end;
+ }
+
+ /* get rds blocks */
+ if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0)
+ /* No RDS group ready, better luck next time */
+ goto end;
+
+ for (blocknum = 0; blocknum < 4; blocknum++) {
+ switch (blocknum) {
+ default:
+ bler = (radio->registers[STATUSRSSI] &
+ STATUSRSSI_BLERA) >> 9;
+ rds = radio->registers[RDSA];
+ break;
+ case 1:
+ bler = (radio->registers[READCHAN] &
+ READCHAN_BLERB) >> 14;
+ rds = radio->registers[RDSB];
+ break;
+ case 2:
+ bler = (radio->registers[READCHAN] &
+ READCHAN_BLERC) >> 12;
+ rds = radio->registers[RDSC];
+ break;
+ case 3:
+ bler = (radio->registers[READCHAN] &
+ READCHAN_BLERD) >> 10;
+ rds = radio->registers[RDSD];
+ break;
+ }
+
+ /* Fill the V4L2 RDS buffer */
+ put_unaligned_le16(rds, &tmpbuf);
+ tmpbuf[2] = blocknum; /* offset name */
+ tmpbuf[2] |= blocknum << 3; /* received offset */
+ if (bler > max_rds_errors)
+ tmpbuf[2] |= 0x80; /* uncorrectable errors */
+ else if (bler > 0)
+ tmpbuf[2] |= 0x40; /* corrected error(s) */
+
+ /* copy RDS block to internal buffer */
+ 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;
+ }
+ }
+
+ if (radio->wr_index != radio->rd_index)
+ wake_up_interruptible(&radio->read_queue);
+
+end:
+ return IRQ_HANDLED;
+}
+
+
+/*
+ * si470x_i2c_probe - probe for the device
+ */
+static int si470x_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct si470x_device *radio;
+ int retval = 0;
+ unsigned char version_warning = 0;
+
+ /* private data allocation and initialization */
+ radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
+ if (!radio) {
+ retval = -ENOMEM;
+ goto err_initial;
+ }
+
+ radio->client = client;
+ radio->band = 1; /* Default to 76 - 108 MHz */
+ mutex_init(&radio->lock);
+ init_completion(&radio->completion);
+
+ /* video device initialization */
+ radio->videodev = si470x_viddev_template;
+ video_set_drvdata(&radio->videodev, radio);
+
+ /* power up : need 110ms */
+ radio->registers[POWERCFG] = POWERCFG_ENABLE;
+ if (si470x_set_register(radio, POWERCFG) < 0) {
+ retval = -EIO;
+ goto err_radio;
+ }
+ msleep(110);
+
+ /* get device and chip versions */
+ if (si470x_get_all_registers(radio) < 0) {
+ retval = -EIO;
+ goto err_radio;
+ }
+ dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
+ radio->registers[DEVICEID], radio->registers[CHIPID]);
+ if ((radio->registers[CHIPID] & CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
+ dev_warn(&client->dev,
+ "This driver is known to work with "
+ "firmware version %hu,\n", RADIO_FW_VERSION);
+ dev_warn(&client->dev,
+ "but the device has firmware version %hu.\n",
+ radio->registers[CHIPID] & CHIPID_FIRMWARE);
+ version_warning = 1;
+ }
+
+ /* give out version warning */
+ if (version_warning == 1) {
+ dev_warn(&client->dev,
+ "If you have some trouble using this driver,\n");
+ dev_warn(&client->dev,
+ "please report to V4L ML at "
+ "linux-media@vger.kernel.org\n");
+ }
+
+ /* set initial frequency */
+ si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
+
+ /* rds buffer allocation */
+ radio->buf_size = rds_buf * 3;
+ radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
+ if (!radio->buffer) {
+ retval = -EIO;
+ goto err_radio;
+ }
+
+ /* rds buffer configuration */
+ radio->wr_index = 0;
+ radio->rd_index = 0;
+ init_waitqueue_head(&radio->read_queue);
+
+ retval = request_threaded_irq(client->irq, NULL, si470x_i2c_interrupt,
+ IRQF_TRIGGER_FALLING, DRIVER_NAME, radio);
+ if (retval) {
+ dev_err(&client->dev, "Failed to register interrupt\n");
+ goto err_rds;
+ }
+
+ /* register video device */
+ retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
+ radio_nr);
+ if (retval) {
+ dev_warn(&client->dev, "Could not register video device\n");
+ goto err_all;
+ }
+ i2c_set_clientdata(client, radio);
+
+ return 0;
+err_all:
+ free_irq(client->irq, radio);
+err_rds:
+ kfree(radio->buffer);
+err_radio:
+ kfree(radio);
+err_initial:
+ return retval;
+}
+
+
+/*
+ * si470x_i2c_remove - remove the device
+ */
+static int si470x_i2c_remove(struct i2c_client *client)
+{
+ struct si470x_device *radio = i2c_get_clientdata(client);
+
+ free_irq(client->irq, radio);
+ video_unregister_device(&radio->videodev);
+ kfree(radio);
+
+ return 0;
+}
+
+
+#ifdef CONFIG_PM_SLEEP
+/*
+ * si470x_i2c_suspend - suspend the device
+ */
+static int si470x_i2c_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct si470x_device *radio = i2c_get_clientdata(client);
+
+ /* power down */
+ radio->registers[POWERCFG] |= POWERCFG_DISABLE;
+ if (si470x_set_register(radio, POWERCFG) < 0)
+ return -EIO;
+
+ return 0;
+}
+
+
+/*
+ * si470x_i2c_resume - resume the device
+ */
+static int si470x_i2c_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct si470x_device *radio = i2c_get_clientdata(client);
+
+ /* power up : need 110ms */
+ radio->registers[POWERCFG] |= POWERCFG_ENABLE;
+ if (si470x_set_register(radio, POWERCFG) < 0)
+ return -EIO;
+ msleep(110);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(si470x_i2c_pm, si470x_i2c_suspend, si470x_i2c_resume);
+#endif
+
+
+/*
+ * si470x_i2c_driver - i2c driver interface
+ */
+static struct i2c_driver si470x_i2c_driver = {
+ .driver = {
+ .name = "si470x",
+ .owner = THIS_MODULE,
+#ifdef CONFIG_PM_SLEEP
+ .pm = &si470x_i2c_pm,
+#endif
+ },
+ .probe = si470x_i2c_probe,
+ .remove = si470x_i2c_remove,
+ .id_table = si470x_i2c_id,
+};
+
+module_i2c_driver(si470x_i2c_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VERSION);