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USB: ark3116: Setup some basic infrastructure for new ark3116 driver.
Signed-off-by: Bart Hartgers <[email protected]> Cc: Mike McCormack <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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@@ -1,15 +1,20 @@ | ||
/* | ||
* Copyright (C) 2009 by Bart Hartgers ([email protected]) | ||
* Original version: | ||
* Copyright (C) 2006 | ||
* Simon Schulz (ark3116_driver <at> auctionant.de) | ||
* | ||
* ark3116 | ||
* - implements a driver for the arkmicro ark3116 chipset (vendor=0x6547, | ||
* productid=0x0232) (used in a datacable called KQ-U8A) | ||
* | ||
* - based on code by krisfx -> thanks !! | ||
* (see http://www.linuxquestions.org/questions/showthread.php?p=2184457#post2184457) | ||
* Supports full modem status lines, break, hardware flow control. Does not | ||
* support software flow control, since I do not know how to enable it in hw. | ||
* | ||
* - based on logs created by usbsnoopy | ||
* This driver is a essentially new implementation. I initially dug | ||
* into the old ark3116.c driver and suddenly realized the ark3116 is | ||
* a 16450 with a USB interface glued to it. See comments at the | ||
* bottom of this file. | ||
* | ||
* 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 | ||
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@@ -19,15 +24,31 @@ | |
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#include <linux/kernel.h> | ||
#include <linux/init.h> | ||
#include <linux/ioctl.h> | ||
#include <linux/tty.h> | ||
#include <linux/tty_flip.h> | ||
#include <linux/module.h> | ||
#include <linux/usb.h> | ||
#include <linux/usb/serial.h> | ||
#include <linux/serial.h> | ||
#include <linux/serial_reg.h> | ||
#include <linux/uaccess.h> | ||
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#include <linux/mutex.h> | ||
#include <linux/spinlock.h> | ||
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static int debug; | ||
/* | ||
* Version information | ||
*/ | ||
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#define DRIVER_VERSION "v0.5" | ||
#define DRIVER_AUTHOR "Bart Hartgers <[email protected]>" | ||
#define DRIVER_DESC "USB ARK3116 serial/IrDA driver" | ||
#define DRIVER_DEV_DESC "ARK3116 RS232/IrDA" | ||
#define DRIVER_NAME "ark3116" | ||
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/* usb timeout of 1 second */ | ||
#define ARK_TIMEOUT (1*HZ) | ||
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static struct usb_device_id id_table [] = { | ||
{ USB_DEVICE(0x6547, 0x0232) }, | ||
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@@ -45,6 +66,53 @@ static int is_irda(struct usb_serial *serial) | |
return 0; | ||
} | ||
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struct ark3116_private { | ||
wait_queue_head_t delta_msr_wait; | ||
struct async_icount icount; | ||
int irda; /* 1 for irda device */ | ||
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/* protects hw register updates */ | ||
struct mutex hw_lock; | ||
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int quot; /* baudrate divisor */ | ||
__u32 lcr; /* line control register value */ | ||
__u32 hcr; /* handshake control register (0x8) | ||
* value */ | ||
__u32 mcr; /* modem contol register value */ | ||
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/* protects the status values below */ | ||
spinlock_t status_lock; | ||
__u32 msr; /* modem status register value */ | ||
__u32 lsr; /* line status register value */ | ||
}; | ||
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static int ark3116_write_reg(struct usb_serial *serial, | ||
unsigned reg, __u8 val) | ||
{ | ||
int result; | ||
/* 0xfe 0x40 are magic values taken from original driver */ | ||
result = usb_control_msg(serial->dev, | ||
usb_sndctrlpipe(serial->dev, 0), | ||
0xfe, 0x40, val, reg, | ||
NULL, 0, ARK_TIMEOUT); | ||
return result; | ||
} | ||
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static int ark3116_read_reg(struct usb_serial *serial, | ||
unsigned reg, unsigned char *buf) | ||
{ | ||
int result; | ||
/* 0xfe 0xc0 are magic values taken from original driver */ | ||
result = usb_control_msg(serial->dev, | ||
usb_rcvctrlpipe(serial->dev, 0), | ||
0xfe, 0xc0, 0, reg, | ||
buf, 1, ARK_TIMEOUT); | ||
if (result < 0) | ||
return result; | ||
else | ||
return buf[0]; | ||
} | ||
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static inline void ARK3116_SND(struct usb_serial *serial, int seq, | ||
__u8 request, __u8 requesttype, | ||
__u16 value, __u16 index) | ||
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@@ -465,7 +533,12 @@ static int __init ark3116_init(void) | |
if (retval) | ||
return retval; | ||
retval = usb_register(&ark3116_driver); | ||
if (retval) | ||
if (retval == 0) { | ||
printk(KERN_INFO "%s:" | ||
DRIVER_VERSION ":" | ||
DRIVER_DESC "\n", | ||
KBUILD_MODNAME); | ||
} else | ||
usb_serial_deregister(&ark3116_device); | ||
return retval; | ||
} | ||
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@@ -480,6 +553,109 @@ module_init(ark3116_init); | |
module_exit(ark3116_exit); | ||
MODULE_LICENSE("GPL"); | ||
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MODULE_AUTHOR(DRIVER_AUTHOR); | ||
MODULE_DESCRIPTION(DRIVER_DESC); | ||
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module_param(debug, bool, S_IRUGO | S_IWUSR); | ||
MODULE_PARM_DESC(debug, "Debug enabled or not"); | ||
MODULE_PARM_DESC(debug, "Enable debug"); | ||
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/* | ||
* The following describes what I learned from studying the old | ||
* ark3116.c driver, disassembling the windows driver, and some lucky | ||
* guesses. Since I do not have any datasheet or other | ||
* documentation, inaccuracies are almost guaranteed. | ||
* | ||
* Some specs for the ARK3116 can be found here: | ||
* http://web.archive.org/web/20060318000438/ | ||
* www.arkmicro.com/en/products/view.php?id=10 | ||
* On that page, 2 GPIO pins are mentioned: I assume these are the | ||
* OUT1 and OUT2 pins of the UART, so I added support for those | ||
* through the MCR. Since the pins are not available on my hardware, | ||
* I could not verify this. | ||
* Also, it states there is "on-chip hardware flow control". I have | ||
* discovered how to enable that. Unfortunately, I do not know how to | ||
* enable XON/XOFF (software) flow control, which would need support | ||
* from the chip as well to work. Because of the wording on the web | ||
* page there is a real possibility the chip simply does not support | ||
* software flow control. | ||
* | ||
* I got my ark3116 as part of a mobile phone adapter cable. On the | ||
* PCB, the following numbered contacts are present: | ||
* | ||
* 1:- +5V | ||
* 2:o DTR | ||
* 3:i RX | ||
* 4:i DCD | ||
* 5:o RTS | ||
* 6:o TX | ||
* 7:i RI | ||
* 8:i DSR | ||
* 10:- 0V | ||
* 11:i CTS | ||
* | ||
* On my chip, all signals seem to be 3.3V, but 5V tolerant. But that | ||
* may be different for the one you have ;-). | ||
* | ||
* The windows driver limits the registers to 0-F, so I assume there | ||
* are actually 16 present on the device. | ||
* | ||
* On an UART interrupt, 4 bytes of data come in on the interrupt | ||
* endpoint. The bytes are 0xe8 IIR LSR MSR. | ||
* | ||
* The baudrate seems to be generated from the 12MHz crystal, using | ||
* 4-times subsampling. So quot=12e6/(4*baud). Also see description | ||
* of register E. | ||
* | ||
* Registers 0-7: | ||
* These seem to be the same as for a regular 16450. The FCR is set | ||
* to UART_FCR_DMA_SELECT (0x8), I guess to enable transfers between | ||
* the UART and the USB bridge/DMA engine. | ||
* | ||
* Register 8: | ||
* By trial and error, I found out that bit 0 enables hardware CTS, | ||
* stopping TX when CTS is +5V. Bit 1 does the same for RTS, making | ||
* RTS +5V when the 3116 cannot transfer the data to the USB bus | ||
* (verified by disabling the reading URB). Note that as far as I can | ||
* tell, the windows driver does NOT use this, so there might be some | ||
* hardware bug or something. | ||
* | ||
* According to a patch provided here | ||
* (http://lkml.org/lkml/2009/7/26/56), the ARK3116 can also be used | ||
* as an IrDA dongle. Since I do not have such a thing, I could not | ||
* investigate that aspect. However, I can speculate ;-). | ||
* | ||
* - IrDA encodes data differently than RS232. Most likely, one of | ||
* the bits in registers 9..E enables the IR ENDEC (encoder/decoder). | ||
* - Depending on the IR transceiver, the input and output need to be | ||
* inverted, so there are probably bits for that as well. | ||
* - IrDA is half-duplex, so there should be a bit for selecting that. | ||
* | ||
* This still leaves at least two registers unaccounted for. Perhaps | ||
* The chip can do XON/XOFF or CRC in HW? | ||
* | ||
* Register 9: | ||
* Set to 0x00 for IrDA, when the baudrate is initialised. | ||
* | ||
* Register A: | ||
* Set to 0x01 for IrDA, at init. | ||
* | ||
* Register B: | ||
* Set to 0x01 for IrDA, 0x00 for RS232, at init. | ||
* | ||
* Register C: | ||
* Set to 00 for IrDA, at init. | ||
* | ||
* Register D: | ||
* Set to 0x41 for IrDA, at init. | ||
* | ||
* Register E: | ||
* Somekind of baudrate override. The windows driver seems to set | ||
* this to 0x00 for normal baudrates, 0x01 for 460800, 0x02 for 921600. | ||
* Since 460800 and 921600 cannot be obtained by dividing 3MHz by an integer, | ||
* it could be somekind of subdivisor thingy. | ||
* However,it does not seem to do anything: selecting 921600 (divisor 3, | ||
* reg E=2), still gets 1 MHz. I also checked if registers 9, C or F would | ||
* work, but they don't. | ||
* | ||
* Register F: unknown | ||
*/ |