Ian Lepore 9ad221a558 Add tsw_busy support to usb_serial (ucom). ... The tty layer uses tsw_busy to poll for busy/idle status of the transmitter hardware during close() and tcdrain(). The ucom layer defines ULSR_TXRDY and ULSR_TSRE bits for the line status register; when both are set, the transmitter is idle. Not all chip drivers maintain those bits in the sc_lsr field, and if the bits never get set the transmitter will always appear busy, causing hangs in tcdrain(). These changes add a new sc_flag bit, UCOM_FLAG_LSRTXIDLE. When this flag is set, ucom_busy() uses the lsr bits to return busy vs. idle state, otherwise it always returns idle (which is effectively what happened before this change because tsw_busy wasn't implemented). For the uftdi chip driver, these changes stop masking out the tx idle bits when processing the status register (because now they're useful), and it calls ucom_use_lsr_txbits() to indicate the bits are maintained by the driver and can be used by ucom_busy(). Differential Revision: https://reviews.freebsd.org/D9183		2017-02-05 15:45:31 +00:00
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u3g.c	Add new USB ID.	2016-09-30 05:28:11 +00:00
uark.c	Annotate the usb-serial drivers which always return 0 for line status,	2016-07-27 00:08:01 +00:00
ubsa.c	Translate modem status reg bits from ns16550 to SER_* values used by the	2016-07-27 00:03:18 +00:00
ubser.c
uchcom.c	Annotate the usb-serial drivers which always return 0 for line status,	2016-07-27 00:08:01 +00:00
ucycom.c	Create a USB_PNP_INFO and use it to export the existing PNP	2015-12-11 05:28:00 +00:00
ufoma.c	Annotate the usb-serial drivers which always return 0 for line status,	2016-07-27 00:08:01 +00:00
uftdi.c	Add tsw_busy support to usb_serial (ucom).	2017-02-05 15:45:31 +00:00
uftdi_reg.h	Add support to the uftdi driver for reading and writing the serial eeprom	2015-08-06 19:29:26 +00:00
ugensa.c	Create a USB_PNP_INFO and use it to export the existing PNP	2015-12-11 05:28:00 +00:00
uipaq.c	Create a USB_PNP_INFO and use it to export the existing PNP	2015-12-11 05:28:00 +00:00
ulpt.c	dev/usb: minor spelling fixes in comments.	2016-05-02 17:44:03 +00:00
umcs.c	Translate modem status reg bits from ns16550 to SER_* values used by the	2016-07-26 23:27:28 +00:00
umcs.h	dev/usb: minor spelling fixes in comments.	2016-05-02 17:44:03 +00:00
umct.c	Translate modem status reg bits from ns16550 to SER_* values used by the	2016-07-26 23:42:42 +00:00
umodem.c	Annotate the usb-serial drivers which always return 0 for line status,	2016-07-27 00:08:01 +00:00
umoscom.c	Actually return line status register values from umoscom_cfg_get_status().	2016-07-26 22:26:49 +00:00
uplcom.c	With clang 3.9.0, compiling uplcom results in the following warnings:	2016-09-04 16:59:35 +00:00
usb_serial.c	Add tsw_busy support to usb_serial (ucom).	2017-02-05 15:45:31 +00:00
usb_serial.h	Add tsw_busy support to usb_serial (ucom).	2017-02-05 15:45:31 +00:00
uslcom.c	Annotate the usb-serial drivers which always return 0 for line status,	2016-07-27 00:08:01 +00:00
uvisor.c	dev/usb: minor spelling fixes in comments.	2016-05-02 17:44:03 +00:00
uvscom.c	Create a USB_PNP_INFO and use it to export the existing PNP	2015-12-11 05:28:00 +00:00