Alexander Sverdlin bb07f4c93e serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access ... commit d96f04d347 upstream. It has been observed that once per 300-1300 port openings the first transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared as "e" on the wire). It only happened if single byte has been transmitted right after port open, which means, DMA is not used for this transfer and the corruption never happened afterwards. Therefore I've carefully re-read the MDR1 errata (link below), which says "when accessing the MDR1 registers that causes a dummy under-run condition that will freeze the UART in IrDA transmission. In UART mode, this may corrupt the transferred data". Strictly speaking, omap_8250_mdr1_errataset() performs a read access and if the value is the same as should be written, exits without errata-recommended FIFO reset. A brief check of the serial_omap_mdr1_errataset() from the competing omap-serial driver showed it has no read access of MDR1. After removing the read access from omap_8250_mdr1_errataset() the data corruption never happened any more. Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf Fixes: 61929cf016 ("tty: serial: Add 8250-core based omap driver") Cc: stable@vger.kernel.org Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-12-21 13:27:06 +01:00
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hvc	tty: hvcs: Don't NULL tty->driver_data until hvcs_cleanup()	2020-10-29 09:57:38 +01:00
ipwireless	tty: ipwireless: fix error handling	2020-10-29 09:58:08 +01:00
serdev	serdev: ttyport: restore client ops on deregistration	2020-02-28 17:22:19 +01:00
serial	serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access	2020-12-21 13:27:06 +01:00
vt	vt: Disable KD_FONT_OP_COPY	2020-11-10 12:37:31 +01:00
Kconfig	…
Makefile	…
amiserial.c	…
cyclades.c	…
ehv_bytechan.c	tty: evh_bytechan: Fix out of bounds accesses	2020-04-23 10:36:44 +02:00
goldfish.c	…
isicom.c	…
mips_ejtag_fdc.c	…
moxa.c	…
moxa.h	…
mxser.c	…
mxser.h	…
n_gsm.c	tty: n_gsm: Fix bogus i++ in gsm_data_kick	2020-06-24 17:50:29 +02:00
n_hdlc.c	…
n_null.c	…
n_r3964.c	…
n_tracerouter.c	…
n_tracesink.c	…
n_tracesink.h	…
n_tty.c	…
nozomi.c	…
pty.c	pty: do tty_flip_buffer_push without port->lock in pty_write	2020-10-29 09:57:38 +01:00
rocket.c	tty: rocket, avoid OOB access	2020-04-29 16:33:17 +02:00
rocket.h	…
rocket_int.h	…
synclink.c	…
synclink_gt.c	tty: synclink_gt: Adjust indentation in several functions	2020-02-24 08:36:47 +01:00
synclinkmp.c	tty: synclinkmp: Adjust indentation in several functions	2020-02-24 08:36:47 +01:00
sysrq.c	…
tty_audit.c	…
tty_baudrate.c	…
tty_buffer.c	…
tty_io.c	tty: Fix ->session locking	2020-12-11 13:23:28 +01:00
tty_ioctl.c	…
tty_jobctrl.c	tty: Fix ->session locking	2020-12-11 13:23:28 +01:00
tty_ldisc.c	…
tty_ldsem.c	…
tty_mutex.c	…
tty_port.c	serdev: ttyport: restore client ops on deregistration	2020-02-28 17:22:19 +01:00
ttynull.c	…
vcc.c	sparc64: vcc: Fix error return code in vcc_probe()	2020-10-01 13:17:57 +02:00