Commit Graph

101 Commits

Author SHA1 Message Date
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Fabio Estevam 93d94b37fd serial: imx: Fix warning when building 'allmodconfig'
When CONFIG_SERIAL_IMX_CONSOLE=n and CONFIG_CONSOLE_POLL=y we get the following
build warning:

drivers/tty/serial/imx.c:306:13: warning: 'imx_port_ucrs_save' defined but not used [-Wunused-function]
drivers/tty/serial/imx.c:315:13: warning: 'imx_port_ucrs_restore' defined but not used [-Wunused-function]

imx_port_ucrs_save/restore are only used under CONFIG_SERIAL_IMX_CONSOLE, so
their definitions should be also be protected only by CONFIG_SERIAL_IMX_CONSOLE.

This was detected when building 'allmodconfig'.

Reported-by: Olof's autobuilder <build@lixom.net>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25 17:06:39 -08:00
Daniel Thompson 6b8bdad961 serial: imx: add imx_poll_init()
For the console poll usage, .poll_init() will perform deeper hardware
initialization to ensure the serial port is always active.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Huang Shijie <b32955@freescale.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 14:57:23 -08:00
Daniel Thompson f968ef3494 serial: imx: clean up imx_poll_put_char()
imx_put_poll_char() has been simplified to remove the code to disable
interrupts. The present code can corrupt register state when re-entered
from FIQ handler.

Switch to _relaxed() MMIO functions (which are safe for polled I/O and
needed to avoid taking spin locks).

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Huang Shijie <b32955@freescale.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 14:57:23 -08:00
Fabio Estevam f0fd1b73b0 serial: imx: Remove unneeded registration message
There is no real value in displaying "Serial: IMX driver" in every boot.

The uart_register_driver() can fail and even so the "Serial: IMX driver" will
be displayed, which is not really helpful.

This is particularly annoying when booting multi_v7_defconfig kernel on a SoC
that is not a i.MX and even though this message gets displayed.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:03:20 -08:00
Fabio Estevam f1f2b6e497 serial: imx: Remove unneeded OOM error message
When kzalloc() fails the core MM will already complain about it, so there is
no need to have the error message locally.

Remove the unneeded error message.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:03:20 -08:00
Fabio Estevam cb0f0a5ff4 serial: imx: Remove unneeded goto label
Instead of jumping to 'error_out1' label we can simplify the code and return the
error code directly.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:03:20 -08:00
Fabio Estevam c0d1c6b0f0 serial: imx: Fix the reporting of interrupts
On a imx system with ttymxc0, ttymxc1 and ttymxc4 registered we see the
following output from 'cat /proc/interrupts':

$ cat /proc/interrupts
           CPU0
...
 58:         39       GIC  58  2020000.serial
 67:        115       GIC  67  21f8000.i2c

The only uart irq that appears is ttymxc0, which is the console.

As ttymxc1 and ttymxc4 will only have their irq registered at imx_startup(),
they are not shown right after probe.

Transmitting to ttymxc1 and ttymxc4 will cause their irqs to be registered, but
the output shows:

$ echo "111111" > /dev/ttymxc1
$ echo "444444" > /dev/ttymxc4
$ cat /proc/interrupts
           CPU0
...
 58:        150       GIC  58  2020000.serial
 59:          1       GIC  59
 62:          1       GIC  62
 67:        115       GIC  67  21f8000.i2c

,which misses printing the associated device address.

In order to fix this, register all the irqs inside the probe function via
devm_request_irq(), which will correctly report the serial interrupts associated
with their correspondent serial device and also helps simplyfing the code by
avoiding the calls to free_irq().

$ echo "111111" > /dev/ttymxc1
$ echo "444444" > /dev/ttymxc4
$ cat /proc/interrupts

	   CPU0
....
 58:        202       GIC  58  2020000.serial
 59:          1       GIC  59  21e8000.serial
 62:          1       GIC  62  21f4000.serial
 67:        115       GIC  67  21f8000.i2c

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:03:20 -08:00
Wolfram Sang 9144b3cded tty: serial: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:21:45 +02:00
Huang Shijie a4688bcd34 serial: imx: change the wait even to interruptiable
The wait_event() makes the application hang for ever in the following case:
 [1] the hardware flow control is enabled.
 [2] the other end (or the remote end) is terminated, and the TX is still
     waiting for the hardware flow control signal to become asserted.

This patch fixes it by changing the wait_event to wait_event_interruptible.

Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-28 21:26:38 -04:00
Huang Shijie 45564a6656 serial: imx: terminate the RX DMA when the UART is suspending
When the uart port is suspending, the RX data is useless.
So in this case, we can terminate the RX DMA right now.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-28 21:26:38 -04:00
Fugang Duan bb2f861ad0 serial: imx: fix throttle/unthrottle callbacks for hardware assisted flow control
when the 'CTSC' bit is negated. 'CTS' has no function when 'CTSC' is asserted.
0: The CTS pin is high (inactive)
1: The CTS pin is low (active)

For throttle, it needs to clear 'CTS' and 'CTSC' bits.
For unthrottle, it needs to enable 'CTS' and 'CTSC' bits.

The patch just fix the issue.

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-28 21:26:38 -04:00
Dirk Behme 26c474128b serial: imx: clean up imx_poll_get_char()
Looking at the get_poll_char() function of the 8250.c serial driver,
we learn:

* poll_get_char() doesn't have to save/disable/restore the interrupt
  registers. No interrupt handling is needed in this function at all.
  Remove it.

* Don't block in case there is no data available. So instead blocking
  in the do {} while loop, just return with NO_POLL_CHAR, immediately .

Additionally, while the i.MX6 register URXD[7-0] contain the RX_DATA,
the upper bits of this register (URXD[15-10]) might contain some
control flags. To ensure that these are not returned with the data
read, just mask out URXD[7-0].

These changes fix the 'hang' working with kdb:

$ echo ttymxc3 > /sys/module/kgdboc/parameters/kgdboc
$ echo g >/proc/sysrq-trigger
[0]kdb> help
...
<hang>

Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 16:26:07 -07:00
Peter Hurley 5e42e9a30c serial: imx: Fix x_char handling and tx flow control
The serial core expects the UART driver to transmit x_char
(START/STOP chars) even if tx is stopped and before data already
in the tx ring buffer if possible. Also, sending x_char must
not cause additional data in the tx ring buffer to transmit
if tx is stopped.

Cause x_char to be transmitted before any other data is sent.
Auto-stop tx if the tx ring buffer is empty or tx should be stopped.
Only perform one write wakeup if tx ring buffer space is below
threshold.

x_char handling in DMA mode is still broken; add FIXME.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 16:21:35 -07:00
Peter Hurley 8bec751bd6 serial: imx: Fix build breakage
Fix breakage introduced by
commit c557d392fb,
'serial: Test for no tx data on tx restart'.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 17:43:13 -07:00
Peter Hurley c557d392fb serial: Test for no tx data on tx restart
Commit 717f3bbab3,
'serial_core: Fix conditional start_tx on ring buffer not empty'
exposes an incorrect assumption in several drivers' start_tx methods;
the tx ring buffer can, in fact, be empty when restarting tx while
performing flow control.

Affected drivers:
sunsab.c
ip22zilog.c
pmac_zilog.c
sunzilog.c
m32r_sio.c
imx.c

Other in-tree serial drivers either are not affected or already
test for empty tx ring buffer before transmitting.

Test for empty tx ring buffer in start_tx() method, after transmitting
x_char (if applicable).

Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Seth Bollinger <sethb@digi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org> # 3.15
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 16:31:34 -07:00
Greg Kroah-Hartman 9ce4f8f3f4 Revert "serial: imx: remove the DMA wait queue"
This reverts commit e2f2786606.

Huang reports that this patch is broken and should be reverted.

Cc: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-29 19:30:54 -07:00
Huang Shijie 85878399e7 serial: imx: disable the receiver ready interrupt for imx_stop_rx
This patch disables the receiver ready interrupt for imx_stop_rx.
It reduces the interrupt numbers when the uart is going to close
or suspend.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:41:32 -07:00
Huang Shijie e2f2786606 serial: imx: remove the DMA wait queue
The DMA wait queue makes the code very complicated:
  For RX, the @->stop_rx hook does not really stop the RX;
  For TX, the @->stop_tx hook does not really stop the TX.

The above make the imx_shutdown has to wait the RX/TX DMA to be finished.

In order to make code more simple, this patch removes the DMA wait queue.
By calling the dmaengine_terminate_all, this patch makes the RX stops
immediately after we call the @->stop_rx hook, so does the TX.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:41:32 -07:00
Huang Shijie 8eccd0cd21 serial: imx: remove the redundant code
In the imx_startup(), we will reset the uart port which will reset all
the FIFOs, including the URXD.

So the code to clear the RX FIFO is redundant. Just remove it.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:40:43 -07:00
Huang Shijie 772f89910a serial: imx: reset the uart port all the time
Current code resets the uart port only when it supports the irda mode.
In actually, we also need to reset the uart port in the non-irda mode.
A hang was caught in the following case:

    UART A transmits data to the other end. But the transmission maybe
    terminated. In some corner case, the TX FIFO maybe not empty.

The kernel will hang at the imx_set_termios():
	............................................................
	while (!(readl(sport->port.membase + USR2) & USR2_TXDC))
		barrier();
	............................................................

This patch resets the uart port all the time in the imx_startup().
And fix the hang.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:39:46 -07:00
Fabio Estevam b38cb7d257 serial: imx: Disable new features of autobaud detection
Bit 7 of UCR3 is described in the i.MX reference manuals (with the exception
of i.MX1) as follows:

ADNIMP: Autobaud Detection Not Improved-. Disables new features of
	autobaud detection (See Baud Rate Automatic Detection
	Protocol, for more details).

	0 Autobaud detection new features selected
	1 Keep old autobaud detection mechanism

The "new features" mechanism occasionally cause the receiver to get out of sync
and continuously produce received characters of '\xff'.

In order to reproduce the problem:

$ stty -F /dev/ttymxc0 19200

- Change the terminal baudrate to 19200

- Type in the console and it should look good

- Change the terminal baudrate back to 115200

- Type 'b' in the console, then a stream of garbage characters is seen.

Also rename the bit definition as per the reference manual.

Tested on mx6q, mx6dl, mx6solo and mx53.

Based on a patch from Eric Nelson for U-boot.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Eric Nelson <eric.nelson@boundarydevices.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:36:21 -07:00
Alexander Shiyan 45af780a0f serial: imx: Remove init() and exit() platform callbacks
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 16:36:45 -08:00
Alexander Shiyan 436e4ab5fc serial: imx: Use dev_name() for request_irq() to distinguish UARTs
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 16:36:45 -08:00
Alexander Shiyan da82f99724 serial: imx: Use devm_ioremap_resource()
Use devm_ioremap_resource() in order to make the code simpler and
it gives proper codes on errors.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 16:36:45 -08:00
Huang Shijie 2ad28e3efe serial: imx: always wake up the processes in the TX callback
The current code only wakes up the processes when the circle
buffer has less data then the WAKEUP_CHARS.

But sometimes, the circle buffer may has data more then the WAKEUP_CHARS,
in such case, the processes will hang.

This patch makes it always wakes up the processes in the TX callback.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13 10:18:48 -08:00
Huang Shijie 6b471a9840 serial: imx: add support for loopback mode.
Add the loopback mode support for imx uart driver.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08 17:09:07 -08:00
Linus Torvalds 56edff7529 TTY/Serial driver updates for 3.13-rc1
Here's the big tty/serial driver update for 3.13-rc1.
 
 There's some more minor n_tty work here, but nothing like previous
 kernel releases.  Also some new driver ids, driver updates for new
 hardware, and other small things.
 
 All of this has been in linux-next for a while with no issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here's the big tty/serial driver update for 3.13-rc1.

  There's some more minor n_tty work here, but nothing like previous
  kernel releases.  Also some new driver ids, driver updates for new
  hardware, and other small things.

  All of this has been in linux-next for a while with no issues"

* tag 'tty-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (84 commits)
  serial: omap: fix missing comma
  serial: sh-sci: Enable the driver on all ARM platforms
  serial: mfd: Staticize local symbols
  serial: omap: fix a few checkpatch warnings
  serial: omap: improve RS-485 performance
  mrst_max3110: fix unbalanced IRQ issue during resume
  serial: omap: Add support for optional wake-up
  serial: sirf: remove duplicate defines
  tty: xuartps: Fix build error when COMMON_CLK is not set
  tty: xuartps: Fix build error due to missing forward declaration
  tty: xuartps: Fix "may be used uninitialized" build warning
  serial: 8250_pci: add Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8
  tty: xuartps: Update copyright information
  tty: xuartps: Implement suspend/resume callbacks
  tty: xuartps: Dynamically adjust to input frequency changes
  tty: xuartps: Updating set_baud_rate()
  tty: xuartps: Force enable the UART in xuartps_console_write
  tty: xuartps: support 64 byte FIFO size
  tty: xuartps: Add polled mode support for xuartps
  tty: xuartps: Implement BREAK detection, add SYSRQ support
  ...
2013-11-07 12:17:06 +09:00
Huang Shijie 7cb92fd2a0 serial: imx: optimization: remove the workqueues for DMA
I worried that the delay of the sdma_run_channel0() maybe too long for
interrupt context, so I added the workqueues for RX/TX DMA.

But tested with bluetooth device, I find that the delay of sdma_run_channel0()
is about 8us (tested in imx6dl sabreauto board). I think the delay
is acceptable.

This patch removes the RX/TX workqueues for DMA, it makes the
code more clear.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 18:25:30 -07:00
Huang Shijie f0ef8834b2 serial: imx: use the dmaengine_tx_status
Use the dmaengine_tx_status to simplify the code, do not change any logic.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 13:19:55 -07:00
Huang Shijie 947c74eba8 serial: imx: fix the wrong number of scatterlist entries when xmit->head is 0
When the (xmit->tail > xmit->head) is true and the xmit->head is 0,
we only need one DMA scatterlist in actually. Current code uses two DMA
scatterlists in this case, this is obviously wrong.

This patch fixes it.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 13:19:54 -07:00
Huang Shijie 1ce43e58d4 serial: imx: check the DMA for imx_tx_empty
Assume the following situation:

  If the DMA is enabled, and the a TX DMA operation is working,
But we have not issued the TX DMA operation (or we have issued the
TX DMA operation with dma_async_issue_pending(), but the DMA has not
started to move the data from the memory to the TXFIFO).

At this time, we may get the wrong status of the transmitter when we
call the imx_tx_empty. In such situation, only check the USR2_TXDC
does not enough for us.

This patch checks the DMA's situation, and return 0 when the TX DMA is
working.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 13:19:54 -07:00
Huang Shijie eb56b7edae serial: imx: implement the flush_buffer hook
The current driver does not implement the flush_buffer hook for
uart_ops. When we enable the DMA for the driver, and test it with Bluetooth,
we may meet the following bug for TX:

    [1] User application may call the flush operation at any time.
        The uart_flush_buffer() calls the uart_circ_clear() to set
        the xmit->head and xmit->tail with 0.

    [2] The TX DMA callback can be called at any time too.
        The dma_tx_call() will update the xmit->tail.

    If [2] occurs just after the [1], we will get the wrong xmit->tail.

This patch implements the flush_buffer hook to fix this issue.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 13:19:54 -07:00
Greg Kroah-Hartman b4e788df8d Revert "serial: i.MX: evaluate linux,stdout-path property"
This reverts commit f7d2c0bbdb, as it
causes build errors when the driver is built as a module.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-07 19:06:59 -07:00
Olof Johansson a50c44ce24 serial: imx: Change cast to handle 64-bit resource_size_t
This resolves a warning where resource_size_t is larger than void *:

  drivers/tty/serial/imx.c:1542:6: warning: cast to pointer from integer
  	of different size [-Wint-to-pointer-cast]

Since iomem_base is a void *, casting to unsigned long is safe.

It's unclear to me that this comparison is truly needed, but it's there
on several other drivers as well.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 15:41:38 -07:00
Fabio Estevam e2c2725338 serial: imx: Use NULL as the last argument of add_preferred_console()
Commit f7d2c0bbd (serial: i.MX: evaluate linux,stdout-path property) introduced
the following sparse warning:

drivers/tty/serial/imx.c:1916:77: warning: Using plain integer as NULL pointer

Pass NULL as the last argument of add_preferred_console() instead of zero.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 14:25:26 -07:00
Huang Shijie b09c74ae12 serial: imx: initialize the local variable
The slave_config is not initialized, so some of its fields may
be set with random data which may causes the failure in the following
dmaengine_prep_slave_sg().

This patch fixes this issue.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-30 14:11:28 -07:00
Sascha Hauer f7d2c0bbdb serial: i.MX: evaluate linux,stdout-path property
devicetrees may have the linux,stdout-path property to specify the
console. This patch adds support to the i.MX serial driver for this.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 11:23:53 -07:00
Jingoo Han 574de559c1 serial: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-31 17:56:15 -07:00
Huang Shijie b4cdc8f61b serial: imx: add DMA support for imx6q
We only enable the DMA support when the following are meet:

  [1] The uart port supports the hardware flow control(CTS/RTS).
      (Some uart port does not support the CTS/RTS.)

  [2] The application enables the CTS/RTS.

  [3] The Soc is imx6q.
      For the sdma's firmware limit, we do not support the DMA except
      the imx6q platform.

  [4] The uart is not used as a console.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 15:44:11 -07:00
Hubert Feurstein 09bd00f6e9 serial/imx: fix custom-baudrate handling
It was not possible to set custom-baudrates like 62500.

Signed-off-by: Hubert Feurstein <h.feurstein@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 15:43:37 -07:00
Huang Shijie a496e6284c serial: imx: distinguish the imx6q uart from the others
We will add the DMA support for the imx uart. For the firmware's limit,
only the imx6 serial chips (including the imx6q, imx6dl, imx6sl) can
support the DMA.

This patch adds the necessary macro and helper to distinguish the
imx6q uart from the other imx uart. Other chips can use the "fsl,imx6q-uart"
to enable the DMA support.

This patch also replaces the check "is_imx21_uart()" with "!is_imx1_uart()".

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 15:43:16 -07:00
Huang Shijie 1cf93e0d54 serial: imx: remove the uart_console() check
The uart_console() check makes the clocks(clk_per and clk_ipg) opened
even when we close the console uart.

This patch enable/disable the clocks in imx_console_write(),
so we can keep the clocks closed when the console uart is closed.

Also remove the clock enable/disable oprations in the probe, we do not
need them any more.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 15:42:46 -07:00
Jingoo Han 43b829b3c1 serial: remove unnecessary platform_set_drvdata()
The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d06310
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Barry Song <baohua.song@csr.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 15:39:36 -07:00
Wolfram Sang e84f54fc58 drivers/tty/serial: don't use devm_pinctrl_get_select_default() in probe
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for setting the default pins. Compile tested only.

Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-24 15:21:13 -07:00
Fabio Estevam 80c48497f2 serial: imx: Fix serial clock unbalance
Since commit 0c375501 (serial: imx: enable the clocks for console), the
imx_startup() function calls clk_prepare_enable conditionally, so we
need to call clk_disable_unprepare inside imx_shutdown() under the same
condition to avoid unbalanced clock calls.

This avoids the following warning:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 70 at drivers/clk/clk.c:780 __clk_disable+0x68/0x84()
Modules linked in:
CPU: 0 PID: 70 Comm: mountall Not tainted 3.10.0-rc4-next-20130607+ #435
Backtrace:
[<800116a4>] (dump_backtrace+0x0/0x10c) from [<80011844>] (show_stack+0x18/0x1c)
 r6:8069f4e8 r5:0000030c r4:00000000 r3:00000000
[<8001182c>] (show_stack+0x0/0x1c) from [<8053bce0>] (dump_stack+0x78/0x94)
[<8053bc68>] (dump_stack+0x0/0x94) from [<80023df8>] (warn_slowpath_common+0x6c/0x8c)
 r4:00000000 r3:00000000
[<80023d8c>] (warn_slowpath_common+0x0/0x8c) from [<80023e3c>] (warn_slowpath_null+0x24/0x2c)
 r8:bf2ed008 r7:bfaa9810 r6:000f0013 r5:bf824b80 r4:bf824b80
[<80023e18>] (warn_slowpath_null+0x0/0x2c) from [<8041af84>] (__clk_disable+0x68/0x84)
[<8041af1c>] (__clk_disable+0x0/0x84) from [<8041b098>] (clk_disable+0x20/0x2c)
 r4:600f0013 r3:00000001
[<8041b078>] (clk_disable+0x0/0x2c) from [<802c93e8>] (imx_shutdown+0xbc/0xec)
 r5:bf824b80 r4:bfaa9810
[<802c932c>] (imx_shutdown+0x0/0xec) from [<802c63a0>] (uart_port_shutdown+0x34/0x40)
 r5:bf86f860 r4:bfaa9810
[<802c636c>] (uart_port_shutdown+0x0/0x40) from [<802c68c0>] (uart_shutdown+0x98/0xc4)
 r4:bf86f800 r3:00000000
[<802c6828>] (uart_shutdown+0x0/0xc4) from [<802c7514>] (uart_close+0x5c/0x198)
 r7:bfaa9810 r6:bf274400 r5:bf86f86c r4:bf86f800
[<802c74b8>] (uart_close+0x0/0x198) from [<802ac648>] (tty_release+0xf8/0x500)
[<802ac550>] (tty_release+0x0/0x500) from [<800c5a30>] (__fput+0x9c/0x208)
[<800c5994>] (__fput+0x0/0x208) from [<800c5bac>] (____fput+0x10/0x14)
[<800c5b9c>] (____fput+0x0/0x14) from [<80040234>] (task_work_run+0xb4/0xec)
[<80040180>] (task_work_run+0x0/0xec) from [<80029238>] (do_exit+0x2b0/0x920)
 r8:8000e144 r7:000000f8 r6:bf306300 r5:00000000 r4:bfac1180
[<80028f88>] (do_exit+0x0/0x920) from [<80029a4c>] (do_group_exit+0x50/0xd4)
 r7:000000f8
[<800299fc>] (do_group_exit+0x0/0xd4) from [<80029ae8>] (__wake_up_parent+0x0/0x28)
 r7:000000f8 r6:00000001 r5:0006f7ae r4:0006f79a
[<80029ad0>] (SyS_exit_group+0x0/0x18) from [<8000dfc0>] (ret_fast_syscall+0x0/0x30)
---[ end trace 16d080eb7efea4e9 ]---

Reported-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 12:49:43 -07:00
Huang Shijie 0c375501be serial: imx: enable the clocks for console
The console's clocks are disabled after the uart driver is probed.
It makes that we can see less log from the console now
(though we still can get all the log by the `dmesg`).

So enable the clocks for console, and we can see all the log again.

This patch also disables the sport->clk_per when we fail to enable
the sport->clk_ipg;

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-08 22:31:47 -07:00
Greg Kroah-Hartman 1ba7055af2 Merge 3.10-rc5 into tty-next 2013-06-08 21:23:33 -07:00
Fabio Estevam e8bfa76073 serial: imx: Fix warning when !CONFIG_SERIAL_IMX_CONSOLE
When CONFIG_SERIAL_IMX_CONSOLE is not selected the following build warnings
appear:

drivers/tty/serial/imx.c:274:13: warning: 'imx_port_ucrs_save' defined but not used [-Wunused-function]
drivers/tty/serial/imx.c:283:13: warning: 'imx_port_ucrs_restore' defined but not used [-Wunused-function]

imx_port_ucrs_save() and imx_port_ucrs_restore() are only used when
CONFIG_CONSOLE_POLL or CONFIG_SERIAL_IMX_CONSOLE are selected, so protect these
functions declaration with a proper ifdef.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-06 13:09:55 -07:00
Huang Shijie 28eb4274e7 serial: imx: enable the clocks only when the uart is used
Current code opens the clocks when the uart driver is probed.
This will wastes some power if several uarts are enabled, but not really
used.

So close these clocks for uart, and enable the clocks only when
the uart is used.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-06 13:05:38 -07:00