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	While there are a mix of things here, most of the stuff were written from Kernel developer's PoV. So, add them to the driver-api book. A follow up for this patch would be to move documents from there that are specific to sysadmins, adding them to the admin-guide. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Johan Hovold <johan@kernel.org> Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			126 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			126 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
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/*
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 * USB Empeg empeg-car player driver
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 *
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 *	Copyright (C) 2000, 2001
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 *	    Gary Brubaker (xavyer@ix.netcom.com)
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 *
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 *	Copyright (C) 1999 - 2001
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 *	    Greg Kroah-Hartman (greg@kroah.com)
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 *
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 * See Documentation/usb/usb-serial.rst for more information on using this
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 * driver
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 */
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/tty.h>
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#include <linux/tty_driver.h>
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#include <linux/tty_flip.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/uaccess.h>
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#include <linux/usb.h>
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#include <linux/usb/serial.h>
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#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>"
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#define DRIVER_DESC "USB Empeg Mark I/II Driver"
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#define EMPEG_VENDOR_ID			0x084f
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#define EMPEG_PRODUCT_ID		0x0001
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/* function prototypes for an empeg-car player */
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static int  empeg_startup(struct usb_serial *serial);
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static void empeg_init_termios(struct tty_struct *tty);
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static const struct usb_device_id id_table[] = {
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	{ USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) },
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	{ }					/* Terminating entry */
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};
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MODULE_DEVICE_TABLE(usb, id_table);
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static struct usb_serial_driver empeg_device = {
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	.driver = {
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		.owner =	THIS_MODULE,
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		.name =		"empeg",
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	},
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	.id_table =		id_table,
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	.num_ports =		1,
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	.bulk_out_size =	256,
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	.throttle =		usb_serial_generic_throttle,
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	.unthrottle =		usb_serial_generic_unthrottle,
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	.attach =		empeg_startup,
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	.init_termios =		empeg_init_termios,
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};
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static struct usb_serial_driver * const serial_drivers[] = {
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	&empeg_device, NULL
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};
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static int empeg_startup(struct usb_serial *serial)
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{
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	int r;
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	if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
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		dev_err(&serial->dev->dev, "active config #%d != 1 ??\n",
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			serial->dev->actconfig->desc.bConfigurationValue);
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		return -ENODEV;
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	}
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	r = usb_reset_configuration(serial->dev);
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	/* continue on with initialization */
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	return r;
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}
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static void empeg_init_termios(struct tty_struct *tty)
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{
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	struct ktermios *termios = &tty->termios;
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	/*
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	 * The empeg-car player wants these particular tty settings.
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	 * You could, for example, change the baud rate, however the
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	 * player only supports 115200 (currently), so there is really
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	 * no point in support for changes to the tty settings.
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	 * (at least for now)
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	 *
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	 * The default requirements for this device are:
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	 */
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	termios->c_iflag
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		&= ~(IGNBRK	/* disable ignore break */
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		| BRKINT	/* disable break causes interrupt */
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		| PARMRK	/* disable mark parity errors */
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		| ISTRIP	/* disable clear high bit of input characters */
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		| INLCR		/* disable translate NL to CR */
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		| IGNCR		/* disable ignore CR */
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		| ICRNL		/* disable translate CR to NL */
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		| IXON);	/* disable enable XON/XOFF flow control */
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	termios->c_oflag
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		&= ~OPOST;	/* disable postprocess output characters */
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	termios->c_lflag
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		&= ~(ECHO	/* disable echo input characters */
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		| ECHONL	/* disable echo new line */
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		| ICANON	/* disable erase, kill, werase, and rprnt special characters */
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		| ISIG		/* disable interrupt, quit, and suspend special characters */
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		| IEXTEN);	/* disable non-POSIX special characters */
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	termios->c_cflag
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		&= ~(CSIZE	/* no size */
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		| PARENB	/* disable parity bit */
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		| CBAUD);	/* clear current baud rate */
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	termios->c_cflag
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		|= CS8;		/* character size 8 bits */
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	tty_encode_baud_rate(tty, 115200, 115200);
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}
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module_usb_serial_driver(serial_drivers, id_table);
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MODULE_AUTHOR(DRIVER_AUTHOR);
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MODULE_DESCRIPTION(DRIVER_DESC);
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MODULE_LICENSE("GPL v2");
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