// SPDX-License-Identifier: GPL-2.0-or-later /* * 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 */ /* driver definitions */ #define DRIVER_AUTHOR "Joonyoung Shim "; #define DRIVER_CARD "Silicon Labs Si470x FM Radio" #define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers" #define DRIVER_VERSION "1.0.2" /* kernel includes */ #include #include #include #include #include #include "radio-si470x.h" /* I2C Device ID List */ static const struct i2c_device_id si470x_i2c_id[] = { /* Generic Entry */ { "si470x" }, /* 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 */ static int si470x_get_register(struct si470x_device *radio, int regnr) { __be16 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 */ static int si470x_set_register(struct si470x_device *radio, int regnr) { int i; __be16 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; __be16 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 */ static 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 */ static 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 */ static int si470x_vidioc_querycap(struct file *file, void *priv, struct v4l2_capability *capability) { strscpy(capability->driver, DRIVER_NAME, sizeof(capability->driver)); strscpy(capability->card, DRIVER_CARD, sizeof(capability->card)); 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) { struct si470x_device *radio; int retval = 0; /* private data allocation and initialization */ radio = devm_kzalloc(&client->dev, sizeof(*radio), 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); radio->get_register = si470x_get_register; radio->set_register = si470x_set_register; radio->fops_open = si470x_fops_open; radio->fops_release = si470x_fops_release; radio->vidioc_querycap = si470x_vidioc_querycap; retval = v4l2_device_register(&client->dev, &radio->v4l2_dev); if (retval < 0) { dev_err(&client->dev, "couldn't register v4l2_device\n"); goto err_initial; } v4l2_ctrl_handler_init(&radio->hdl, 2); v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops, V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1); v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops, V4L2_CID_AUDIO_VOLUME, 0, 15, 1, 15); if (radio->hdl.error) { retval = radio->hdl.error; dev_err(&client->dev, "couldn't register control\n"); goto err_all; } /* video device initialization */ radio->videodev = si470x_viddev_template; radio->videodev.ctrl_handler = &radio->hdl; radio->videodev.lock = &radio->lock; radio->videodev.v4l2_dev = &radio->v4l2_dev; radio->videodev.release = video_device_release_empty; radio->videodev.device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE | V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE; video_set_drvdata(&radio->videodev, radio); radio->gpio_reset = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_LOW); if (IS_ERR(radio->gpio_reset)) { retval = PTR_ERR(radio->gpio_reset); dev_err(&client->dev, "Failed to request gpio: %d\n", retval); goto err_all; } if (radio->gpio_reset) gpiod_set_value(radio->gpio_reset, 1); /* power up : need 110ms */ radio->registers[POWERCFG] = POWERCFG_ENABLE; if (si470x_set_register(radio, POWERCFG) < 0) { retval = -EIO; goto err_all; } msleep(110); /* get device and chip versions */ if (si470x_get_all_registers(radio) < 0) { retval = -EIO; goto err_all; } dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n", radio->registers[DEVICEID], radio->registers[SI_CHIPID]); if ((radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE) < RADIO_FW_VERSION) { dev_warn(&client->dev, "This driver is known to work with firmware version %u, but the device has firmware version %u.\n" "If you have some trouble using this driver, please report to V4L ML at linux-media@vger.kernel.org\n", RADIO_FW_VERSION, radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE); } /* 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 = devm_kmalloc(&client->dev, radio->buf_size, GFP_KERNEL); if (!radio->buffer) { retval = -EIO; goto err_all; } /* rds buffer configuration */ radio->wr_index = 0; radio->rd_index = 0; init_waitqueue_head(&radio->read_queue); retval = devm_request_threaded_irq(&client->dev, client->irq, NULL, si470x_i2c_interrupt, IRQF_TRIGGER_FALLING | IRQF_ONESHOT, DRIVER_NAME, radio); if (retval) { dev_err(&client->dev, "Failed to register interrupt\n"); goto err_all; } /* 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: v4l2_ctrl_handler_free(&radio->hdl); v4l2_device_unregister(&radio->v4l2_dev); err_initial: return retval; } /* * si470x_i2c_remove - remove the device */ static void si470x_i2c_remove(struct i2c_client *client) { struct si470x_device *radio = i2c_get_clientdata(client); video_unregister_device(&radio->videodev); if (radio->gpio_reset) gpiod_set_value(radio->gpio_reset, 0); v4l2_ctrl_handler_free(&radio->hdl); v4l2_device_unregister(&radio->v4l2_dev); } #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 #if IS_ENABLED(CONFIG_OF) static const struct of_device_id si470x_of_match[] = { { .compatible = "silabs,si470x" }, { }, }; MODULE_DEVICE_TABLE(of, si470x_of_match); #endif /* * si470x_i2c_driver - i2c driver interface */ static struct i2c_driver si470x_i2c_driver = { .driver = { .name = "si470x", .of_match_table = of_match_ptr(si470x_of_match), #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);