* serial_core's port->count mess
@ 2011-05-19 9:38 Pavan Savoy
2011-05-19 10:25 ` Alan Cox
[not found] ` <BANLkTim7OmA1y+Z_4CHZBCKu-uG_=9jJ=A@mail.gmail.com>
0 siblings, 2 replies; 4+ messages in thread
From: Pavan Savoy @ 2011-05-19 9:38 UTC (permalink / raw)
To: linux-serial; +Cc: pavan_savoy
Hi,
I have a device connected to my apps processor over UART, the serial
core's hooked up with omap-serial UART driver.
There is a scenario, where the device just fails to respond, and I
should be closing the UART & opening it again to re-try the request.
This is also coupled with power-cycling the chip.
However a normal start/stop sequence where chip responds to every
request & I close UART when I'm done - is something like this,
[function name & line number in logs)
uart_open(1) called
uart_open: 1635
uart_open: 1651
uart_open: 1663
uart_open: 1674
omap-hsuart omap-hsuart.1: serial_omap_pm+1
omap-hsuart omap-hsuart.1: Enable CTS wakeup for UART 1
omap-hsuart omap-hsuart.1: serial_omap_startup+1
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
omap-hsuart omap-hsuart.1: serial_omap_get_mctrl+1
uart_open: 1686
uart_open: 1694
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
omap-hsuart omap-hsuart.1: serial_omap_set_termios+1
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
uart_open: 1705
uart_flush_buffer(1) called
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
omap-hsuart omap-hsuart.1: serial_omap_set_termios+1
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
omap-hsuart omap-hsuart.1: serial_omap_set_termios+1
uart_flush_buffer(1) called
uart_flush_buffer(1) called
uart_flush_buffer(1) called
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
omap-hsuart omap-hsuart.1: serial_omap_set_termios+1
uart_wait_until_sent(1), jiffies=4294954470, expire=4294954474...
omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1
uart_wait_until_sent(1), jiffies=4294954471, expire=4294954475...
omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1
(stc): st_tty_open
uart_flush_buffer(1) called
uart_flush_buffer(1) called
uart_flush_buffer(1) called
(stk) :ldisc_install = 0
uart_close(1) called
uart_close: 1295
uart_close: 1316
uart_wait_until_sent(1), jiffies=4294951992, expire=4294951996...
omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1
uart_close: 1327
omap-hsuart omap-hsuart.1: Disable CTS wakeup for UART1
uart_wait_until_sent(1), jiffies=4294951994, expire=4294951996...
omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1
uart_close: 1345
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
omap-hsuart omap-hsuart.1: serial_omap_shutdown+1
omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1
uart_flush_buffer(1) called
uart_flush_buffer(1) called
omap-hsuart omap-hsuart.1: serial_omap_pm+1
uart_close: 1368
(stc): st_tty_close
However, in a scenario where the chip fails to respond to one of the
requests, the start/stop sequence becomes something like this,
uart_open(1) called
uart_open: 1635
uart_open: 1651
uart_open: 1663
uart_open: 1705
So, the problem seems to be that the port->count in the serial_core
isn't 1 & hence the call,
if (port->count == 1)
uart_change_pm(state, 0);
doesn't seem to be happening, which is very critical. Also no calls
are made to uart_startup & hence omap-serial's startup.
Where should I be looking as to why the port->count is messed up ?
What is the this count used for?
Also how is this related to chip not responding to certain commands?
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: serial_core's port->count mess 2011-05-19 9:38 serial_core's port->count mess Pavan Savoy @ 2011-05-19 10:25 ` Alan Cox [not found] ` <BANLkTim7OmA1y+Z_4CHZBCKu-uG_=9jJ=A@mail.gmail.com> 1 sibling, 0 replies; 4+ messages in thread From: Alan Cox @ 2011-05-19 10:25 UTC (permalink / raw) To: Pavan Savoy; +Cc: linux-serial > So, the problem seems to be that the port->count in the serial_core > isn't 1 & hence the call, So you've got it open in two places > What is the this count used for? Number of live openers basically > Also how is this related to chip not responding to certain commands? No idea ^ permalink raw reply [flat|nested] 4+ messages in thread
[parent not found: <BANLkTim7OmA1y+Z_4CHZBCKu-uG_=9jJ=A@mail.gmail.com>]
* Re: serial_core's port->count mess [not found] ` <BANLkTim7OmA1y+Z_4CHZBCKu-uG_=9jJ=A@mail.gmail.com> @ 2011-05-19 12:51 ` Pavan Savoy [not found] ` <BANLkTik6f4rFcr+X=ov4y=48QCxF1=zvkg@mail.gmail.com> 0 siblings, 1 reply; 4+ messages in thread From: Pavan Savoy @ 2011-05-19 12:51 UTC (permalink / raw) To: Govindraj; +Cc: linux-serial On Thu, May 19, 2011 at 3:58 PM, Govindraj <govindraj.ti@gmail.com> wrote: > > On Thu, May 19, 2011 at 3:08 PM, Pavan Savoy <pavan_savoy@sify.com> wrote: >> >> Hi, >> >> I have a device connected to my apps processor over UART, the serial >> core's hooked up with omap-serial UART driver. >> There is a scenario, where the device just fails to respond, and I >> should be closing the UART & opening it again to re-try the request. >> This is also coupled with power-cycling the chip. >> >> However a normal start/stop sequence where chip responds to every >> request & I close UART when I'm done - is something like this, >> [function name & line number in logs) >> uart_open(1) called >> uart_open: 1635 >> uart_open: 1651 >> uart_open: 1663 >> uart_open: 1674 >> omap-hsuart omap-hsuart.1: serial_omap_pm+1 >> omap-hsuart omap-hsuart.1: Enable CTS wakeup for UART 1 >> omap-hsuart omap-hsuart.1: serial_omap_startup+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> omap-hsuart omap-hsuart.1: serial_omap_get_mctrl+1 >> uart_open: 1686 >> uart_open: 1694 >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> uart_open: 1705 >> uart_flush_buffer(1) called >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> uart_flush_buffer(1) called >> uart_flush_buffer(1) called >> uart_flush_buffer(1) called >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> uart_wait_until_sent(1), jiffies=4294954470, expire=4294954474... >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> uart_wait_until_sent(1), jiffies=4294954471, expire=4294954475... >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> (stc): st_tty_open >> >> uart_flush_buffer(1) called >> uart_flush_buffer(1) called >> uart_flush_buffer(1) called >> (stk) :ldisc_install = 0 >> uart_close(1) called >> uart_close: 1295 >> uart_close: 1316 >> uart_wait_until_sent(1), jiffies=4294951992, expire=4294951996... >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> uart_close: 1327 >> omap-hsuart omap-hsuart.1: Disable CTS wakeup for UART1 >> uart_wait_until_sent(1), jiffies=4294951994, expire=4294951996... >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> uart_close: 1345 >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> omap-hsuart omap-hsuart.1: serial_omap_shutdown+1 >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> uart_flush_buffer(1) called >> uart_flush_buffer(1) called >> omap-hsuart omap-hsuart.1: serial_omap_pm+1 >> uart_close: 1368 >> (stc): st_tty_close >> >> However, in a scenario where the chip fails to respond to one of the >> requests, the start/stop sequence becomes something like this, >> uart_open(1) called >> uart_open: 1635 >> uart_open: 1651 >> uart_open: 1663 >> uart_open: 1705 >> >> So, the problem seems to be that the port->count in the serial_core >> isn't 1 & hence the call, >> if (port->count == 1) >> uart_change_pm(state, 0); > > Actually port count will be incremented based on number of times > the port will be opened. (file open do on the the given ttyOx interface) > for the first tty open the count gets incremented to one and sets state to > active > (state, 0) > if you open multiple times then the serial_core knows port in active state > so it is not necessary to call uart_change_pm(state, 0) Assuming multiple opens isn't that big a deal... But I get a tcgetattr() failure then, and thereby unable to set the default baud-rate and hence send data over UART. >> doesn't seem to be happening, which is very critical. Also no calls >> are made to uart_startup & hence omap-serial's startup. >> >> Where should I be looking as to why the port->count is messed up ? >> What is the this count used for? >> Also how is this related to chip not responding to certain commands? > > Is the uart_clks cut? Try keeping uart clocks active always. Need to check this then.... How do I make sure they stay on ? > Govindraj.R > >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-serial" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 4+ messages in thread
[parent not found: <BANLkTik6f4rFcr+X=ov4y=48QCxF1=zvkg@mail.gmail.com>]
* Re: serial_core's port->count mess [not found] ` <BANLkTik6f4rFcr+X=ov4y=48QCxF1=zvkg@mail.gmail.com> @ 2011-05-19 13:17 ` Pavan Savoy 0 siblings, 0 replies; 4+ messages in thread From: Pavan Savoy @ 2011-05-19 13:17 UTC (permalink / raw) To: Govindraj; +Cc: linux-serial On Thu, May 19, 2011 at 6:42 PM, Govindraj <govindraj.ti@gmail.com> wrote: > > On Thu, May 19, 2011 at 6:21 PM, Pavan Savoy <pavan_savoy@sify.com> wrote: >> >> On Thu, May 19, 2011 at 3:58 PM, Govindraj <govindraj.ti@gmail.com> wrote: >> > >> > On Thu, May 19, 2011 at 3:08 PM, Pavan Savoy <pavan_savoy@sify.com> >> > wrote: >> >> >> >> Hi, >> >> >> >> I have a device connected to my apps processor over UART, the serial >> >> core's hooked up with omap-serial UART driver. >> >> There is a scenario, where the device just fails to respond, and I >> >> should be closing the UART & opening it again to re-try the request. >> >> This is also coupled with power-cycling the chip. >> >> >> >> However a normal start/stop sequence where chip responds to every >> >> request & I close UART when I'm done - is something like this, >> >> [function name & line number in logs) >> >> uart_open(1) called >> >> uart_open: 1635 >> >> uart_open: 1651 >> >> uart_open: 1663 >> >> uart_open: 1674 >> >> omap-hsuart omap-hsuart.1: serial_omap_pm+1 >> >> omap-hsuart omap-hsuart.1: Enable CTS wakeup for UART 1 >> >> omap-hsuart omap-hsuart.1: serial_omap_startup+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_get_mctrl+1 >> >> uart_open: 1686 >> >> uart_open: 1694 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> uart_open: 1705 >> >> uart_flush_buffer(1) called >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> >> uart_flush_buffer(1) called >> >> uart_flush_buffer(1) called >> >> uart_flush_buffer(1) called >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_termios+1 >> >> uart_wait_until_sent(1), jiffies=4294954470, expire=4294954474... >> >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> >> uart_wait_until_sent(1), jiffies=4294954471, expire=4294954475... >> >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> >> (stc): st_tty_open >> >> >> >> uart_flush_buffer(1) called >> >> uart_flush_buffer(1) called >> >> uart_flush_buffer(1) called >> >> (stk) :ldisc_install = 0 >> >> uart_close(1) called >> >> uart_close: 1295 >> >> uart_close: 1316 >> >> uart_wait_until_sent(1), jiffies=4294951992, expire=4294951996... >> >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> >> uart_close: 1327 >> >> omap-hsuart omap-hsuart.1: Disable CTS wakeup for UART1 >> >> uart_wait_until_sent(1), jiffies=4294951994, expire=4294951996... >> >> omap-hsuart omap-hsuart.1: serial_omap_tx_empty+1 >> >> uart_close: 1345 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_shutdown+1 >> >> omap-hsuart omap-hsuart.1: serial_omap_set_mctrl+1 >> >> uart_flush_buffer(1) called >> >> uart_flush_buffer(1) called >> >> omap-hsuart omap-hsuart.1: serial_omap_pm+1 >> >> uart_close: 1368 >> >> (stc): st_tty_close >> >> >> >> However, in a scenario where the chip fails to respond to one of the >> >> requests, the start/stop sequence becomes something like this, >> >> uart_open(1) called >> >> uart_open: 1635 >> >> uart_open: 1651 >> >> uart_open: 1663 >> >> uart_open: 1705 >> >> >> >> So, the problem seems to be that the port->count in the serial_core >> >> isn't 1 & hence the call, >> >> if (port->count == 1) >> >> uart_change_pm(state, 0); >> > >> > Actually port count will be incremented based on number of times >> > the port will be opened. (file open do on the the given ttyOx interface) >> > for the first tty open the count gets incremented to one and sets state >> > to >> > active >> > (state, 0) >> > if you open multiple times then the serial_core knows port in active >> > state >> > so it is not necessary to call uart_change_pm(state, 0) >> >> Assuming multiple opens isn't that big a deal... >> But I get a tcgetattr() failure then, and thereby unable to set the >> default baud-rate >> and hence send data over UART. > > Whats the error number? strerror throws me Invalid arguments when the tcgetattr() fails. >> >> doesn't seem to be happening, which is very critical. Also no calls >> >> are made to uart_startup & hence omap-serial's startup. >> >> >> >> Where should I be looking as to why the port->count is messed up ? >> >> What is the this count used for? >> >> Also how is this related to chip not responding to certain commands? >> > >> > Is the uart_clks cut? Try keeping uart clocks active always. >> >> Need to check this then.... >> How do I make sure they stay on ? > > you an avoid setting uart timeouts from sysfs entry or > comment out omap_device_idle from */mach-omap2/serial.c file. Yes, kind of familiar with 2nd approach - but need help on the sysfs entry ... which one should I be looking for ? (hopefully available on all omap kernels..) >> >> > Govindraj.R >> > >> >> >> >> -- >> >> To unsubscribe from this list: send the line "unsubscribe linux-serial" >> >> in >> >> the body of a message to majordomo@vger.kernel.org >> >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > >> > > > -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 4+ messages in thread
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2011-05-19 9:38 serial_core's port->count mess Pavan Savoy
2011-05-19 10:25 ` Alan Cox
[not found] ` <BANLkTim7OmA1y+Z_4CHZBCKu-uG_=9jJ=A@mail.gmail.com>
2011-05-19 12:51 ` Pavan Savoy
[not found] ` <BANLkTik6f4rFcr+X=ov4y=48QCxF1=zvkg@mail.gmail.com>
2011-05-19 13:17 ` Pavan Savoy
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