/* * 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] = { { radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM, (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] = { { radio->client->addr, 0, sizeof(u16) * WRITE_REG_NUM, (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] = { { radio->client->addr, I2C_M_RD, sizeof(u16) * READ_REG_NUM, (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; } /************************************************************************** * General Driver Functions - DISCONNECT_CHECK **************************************************************************/ /* * si470x_disconnect_check - check whether radio disconnects */ int si470x_disconnect_check(struct si470x_device *radio) { 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 = 0; mutex_lock(&radio->lock); radio->users++; if (radio->users == 1) { /* 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: mutex_unlock(&radio->lock); return retval; } /* * si470x_fops_release - file release */ int si470x_fops_release(struct file *file) { struct si470x_device *radio = video_drvdata(file); int retval = 0; /* safety check */ if (!radio) return -ENODEV; mutex_lock(&radio->lock); radio->users--; if (radio->users == 0) /* stop radio */ retval = si470x_stop(radio); mutex_unlock(&radio->lock); return retval; } /************************************************************************** * 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->capabilities = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_TUNER | V4L2_CAP_RADIO; 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 __devinit 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->users = 0; radio->client = client; 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); /* power up : need 110ms */ radio->registers[POWERCFG] = POWERCFG_ENABLE; if (si470x_set_register(radio, POWERCFG) < 0) { retval = -EIO; goto err_video; } msleep(110); /* get device and chip versions */ if (si470x_get_all_registers(radio) < 0) { retval = -EIO; goto err_video; } 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_video; } /* rds buffer configuration */ radio->wr_index = 0; radio->rd_index = 0; init_waitqueue_head(&radio->read_queue); /* mark Seek/Tune Complete Interrupt enabled */ radio->stci_enabled = true; init_completion(&radio->completion); 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_video: video_device_release(radio->videodev); err_radio: kfree(radio); err_initial: return retval; } /* * si470x_i2c_remove - remove the device */ static __devexit 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 /* * 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 .pm = &si470x_i2c_pm, #endif }, .probe = si470x_i2c_probe, .remove = __devexit_p(si470x_i2c_remove), .id_table = si470x_i2c_id, }; /************************************************************************** * Module Interface **************************************************************************/ /* * si470x_i2c_init - module init */ static int __init si470x_i2c_init(void) { printk(KERN_INFO DRIVER_DESC ", Version " DRIVER_VERSION "\n"); return i2c_add_driver(&si470x_i2c_driver); } /* * si470x_i2c_exit - module exit */ static void __exit si470x_i2c_exit(void) { i2c_del_driver(&si470x_i2c_driver); } module_init(si470x_i2c_init); module_exit(si470x_i2c_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_VERSION(DRIVER_VERSION);