// SPDX-License-Identifier: GPL-2.0-or-later /* * Driver for the MasterKit MA901 USB FM radio. This device plugs * into the USB port and an analog audio input or headphones, so this thing * only deals with initialization, frequency setting, volume. * * Copyright (c) 2012 Alexey Klimov <[email protected]> */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/input.h> #include <linux/videodev2.h> #include <media/v4l2-device.h> #include <media/v4l2-ioctl.h> #include <media/v4l2-ctrls.h> #include <media/v4l2-event.h> #include <linux/usb.h> #include <linux/mutex.h> #define DRIVER_AUTHOR … #define DRIVER_DESC … #define DRIVER_VERSION … MODULE_AUTHOR(…); MODULE_DESCRIPTION(…); MODULE_LICENSE(…) …; MODULE_VERSION(…); #define USB_MA901_VENDOR … #define USB_MA901_PRODUCT … /* dev_warn macro with driver name */ #define MA901_DRIVER_NAME … #define ma901radio_dev_warn(dev, fmt, arg...) … #define ma901radio_dev_err(dev, fmt, arg...) … /* Probably USB_TIMEOUT should be modified in module parameter */ #define BUFFER_LENGTH … #define USB_TIMEOUT … #define FREQ_MIN … #define FREQ_MAX … #define FREQ_MUL … #define MA901_VOLUME_MAX … #define MA901_VOLUME_MIN … /* Commands that device should understand * List isn't full and will be updated with implementation of new functions */ #define MA901_RADIO_SET_FREQ … #define MA901_RADIO_SET_VOLUME … #define MA901_RADIO_SET_MONO_STEREO … /* Comfortable defines for ma901radio_set_stereo */ #define MA901_WANT_STEREO … #define MA901_WANT_MONO … /* module parameter */ static int radio_nr = …; module_param(radio_nr, int, 0); MODULE_PARM_DESC(…) …; /* Data for one (physical) device */ struct ma901radio_device { … }; static inline struct ma901radio_device *to_ma901radio_dev(struct v4l2_device *v4l2_dev) { … } /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */ static int ma901radio_set_freq(struct ma901radio_device *radio, int freq) { … } static int ma901radio_set_volume(struct ma901radio_device *radio, u16 vol_to_set) { … } static int ma901_set_stereo(struct ma901radio_device *radio, u8 stereo) { … } /* Handle unplugging the device. * We call video_unregister_device in any case. * The last function called in this procedure is * usb_ma901radio_device_release. */ static void usb_ma901radio_disconnect(struct usb_interface *intf) { … } /* vidioc_querycap - query device capabilities */ static int vidioc_querycap(struct file *file, void *priv, struct v4l2_capability *v) { … } /* vidioc_g_tuner - get tuner attributes */ static int vidioc_g_tuner(struct file *file, void *priv, struct v4l2_tuner *v) { … } /* vidioc_s_tuner - set tuner attributes */ static int vidioc_s_tuner(struct file *file, void *priv, const struct v4l2_tuner *v) { … } /* vidioc_s_frequency - set tuner radio frequency */ static int vidioc_s_frequency(struct file *file, void *priv, const struct v4l2_frequency *f) { … } /* vidioc_g_frequency - get tuner radio frequency */ static int vidioc_g_frequency(struct file *file, void *priv, struct v4l2_frequency *f) { … } static int usb_ma901radio_s_ctrl(struct v4l2_ctrl *ctrl) { … } /* TODO: Should we really need to implement suspend and resume functions? * Radio has it's own memory and will continue playing if power is present * on usb port and on resume it will start to play again based on freq, volume * values in device memory. */ static int usb_ma901radio_suspend(struct usb_interface *intf, pm_message_t message) { … } static int usb_ma901radio_resume(struct usb_interface *intf) { … } static const struct v4l2_ctrl_ops usb_ma901radio_ctrl_ops = …; /* File system interface */ static const struct v4l2_file_operations usb_ma901radio_fops = …; static const struct v4l2_ioctl_ops usb_ma901radio_ioctl_ops = …; static void usb_ma901radio_release(struct v4l2_device *v4l2_dev) { … } /* check if the device is present and register with v4l and usb if it is */ static int usb_ma901radio_probe(struct usb_interface *intf, const struct usb_device_id *id) { … } /* USB Device ID List */ static const struct usb_device_id usb_ma901radio_device_table[] = …; MODULE_DEVICE_TABLE(usb, usb_ma901radio_device_table); /* USB subsystem interface */ static struct usb_driver usb_ma901radio_driver = …; module_usb_driver(…) …;
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