Commit Graph

8 Commits

Author SHA1 Message Date
Cyrille Pitchen
05a051436b ARM: at91/dt: add a new DT property to support FIFOs on Atmel USARTs
This patch adds a new DT property, "atmel,fifo-size", to enable and set
the maximum number of data the RX and TX FIFOs can store on FIFO capable
USARTs.

Please be aware that the VERSION register can not be used to guess the
size of FIFOs. Indeed, for a given hardware version, the USARTs can be
integrated on Atmel SoCs with different FIFO sizes. Also the
"atmel,fifo-size" property is optional as older USARTs don't embed FIFO at
all.

Besides, the FIFO size can not be read or guessed from other registers:
When designing the FIFO feature, no dedicated registers were added to
store this size. Unsed spaces in the I/O register range are limited and
better reserved for future usages. Instead, the FIFO size of each
peripheral is documented in the programmer datasheet.

Finally, on a given SoC, there can be several instances of USART with
different FIFO sizes. This explain why we'd rather use a dedicated DT
property than use the "compatible" property.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-23 18:00:42 -07:00
Alexandre Belloni
8c07f664a6 ARM: at91/dt: introduce atmel,<chip>-dbgu
The DBGU is not a simple UART and we need to be able to distinguish it from the
other UARTs, in particular to get its address and check the chip id.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2015-03-13 15:11:04 +01:00
Richard Genoud
e0b0baadb7 tty/serial: at91: use mctrl_gpio helpers
On sam9x5, dedicated CTS (and RTS) pins are unusable together with the
LCDC, the EMAC, or the MMC because they share the same line.

Moreover, the USART controller doesn't handle DTR/DSR/DCD/RI signals,
so we have to control them via GPIO.

This patch permits to use GPIOs to control the CTS/RTS/DTR/DSR/DCD/RI
signals.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:49:44 -07:00
Richard Genoud
7f40605a26 tty/serial: atmel_serial: Fix device tree documentation
RTS pin is an active low pin.
For now, this doesn't change anything as the ACTIVE_LOW flag is not
handled in atmel_serial, but it will be in 3.16.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:44:32 -07:00
Olof Johansson
11d73c56b9 This cleanup series gets rid of <mach/timex.h> for platforms not using
ARCH_MULTIPLATFORM. (For multi-platform code it's already unused since
 387798b (ARM: initial multiplatform support).)
 
 To make this work some code out of arch/arm needed to be adapted. The
 respective changes got acks by their maintainers to be taken via armsoc
 (with Andrew Morton substituting for Alessandro Zummo as rtc maintainer).
 
 Compared to the previous pull request there was another patch added that
 fixes a (non-critical) regression on ixp4xx. Olof Johansson asked to not
 squash this fix into the original commit to save him from the need to
 reverify the series.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABCAAGBQJTA8PeAAoJEOLc3ZEyZpvW5GEP/iz+HIx8Rkf3exUOorZB0Kef
 dPC1Bmc4SThffhgmmXTjSapTzjfnuC8xq8dni008L7QR0LFJsC/rw8bR9GqYhTDs
 EP7Sk0vDJcTUw9dvlIG0jpBioxdsPY7isU8K85tr2a+dzi4JA2h8iv6gE7bsOf1c
 b18hIWp2ZZdeYQX3OcuzPeVfvXuMaayBJChq0akoW7zqxG2nHG9j1vCSOhBtrgpc
 xCTuEqPoaDOdXjdhyda//3SKkIYh1eMf+RWMgW38vz2uHEI3AsMn/EWe6pNRKzRt
 JdVC6LWFl5tl1Dz73NoGFQO+ztTBb2pTrmqggc+Hi4iTekJSmJSFU51D/E0hdJFj
 KmWDWPLiUdAItjPuRz/HyeZxoIZQjg9PJ8MkjwVNAz4f4Vmw2xNnAV1Eur3k9JyV
 fo55eaBvy2KIGzBB+/ksMUvs4HzMJ7Z/dVPzZYRF8VxlYFJXExT0O42oeJ8KsfH7
 dJ1bjk+3VIWPLH3DHyyiIfBL1oxe4MemqrAREFnN2QxYHyCipXLwH35uNZXAqvcU
 jverroWnCdrpOn9KI+vpnp/kuE7Qc1IH/AwAZngPj2xhaFapiH6h1JK/xWcWjijR
 AKv1DhFJMqSp9fvclr/ZAb7o35V/LG0rpCs+oZumCCARwpxkbo8xXgG0CfPsYFrG
 KwLWPz5zwySGwvDZ2wub
 =g6PN
 -----END PGP SIGNATURE-----

Merge tag 'dropmachtimexh-v2' of git://git.pengutronix.de/git/ukl/linux into next/cleanup

This cleanup series gets rid of <mach/timex.h> for platforms not using
ARCH_MULTIPLATFORM. (For multi-platform code it's already unused since
387798b (ARM: initial multiplatform support).)

To make this work some code out of arch/arm needed to be adapted. The
respective changes got acks by their maintainers to be taken via armsoc
(with Andrew Morton substituting for Alessandro Zummo as rtc maintainer).

Compared to the previous pull request there was another patch added that
fixes a (non-critical) regression on ixp4xx. Olof Johansson asked to not
squash this fix into the original commit to save him from the need to
reverify the series.

* tag 'dropmachtimexh-v2' of git://git.pengutronix.de/git/ukl/linux:
  ARM: ixp4xx: fix timer latch calculation
  ARM: drop <mach/timex.h> for !ARCH_MULTIPLATFORM, too
  ARM: rpc: stop using <mach/timex.h>
  ARM: ixp4xx: stop using <mach/timex.h>
  input: ixp4xx-beeper: don't use symbols from <mach/timex.h>
  ARM: at91: don't use <mach/timex.h>
  ARM: ep93xx: stop using mach/timex.h
  ARM: mmp: stop using mach/timex.h
  ARM: netx: stop using mach/timex.h
  ARM: sa1100: stop using mach/timex.h
  clocksource: sirf/marco+prima2: drop usage of CLOCK_TICK_RATE
  rtc: pxa: drop unused #define TIMER_FREQ
  rtc: at91sam9: include <mach/hardware.h> explicitly
  ARM/serial: at91: switch atmel serial to use gpiolib

Signed-off-by: Olof Johansson <olof@lixom.net>
2014-02-18 22:19:33 -08:00
Linus Walleij
354e57f3a0 ARM/serial: at91: switch atmel serial to use gpiolib
This passes the errata fix using a GPIO to control the RTS pin
on one of the AT91 chips to use gpiolib instead of the
AT91-specific interfaces. Also remove the reliance on
compile-time #defines and the cpu_* check and rely on the
platform passing down the proper GPIO pin through platform
data.

This is a prerequisite for getting rid of the local GPIO
implementation in the AT91 platform and move toward
multiplatform.

The patch also adds device tree support for getting the
RTS GPIO pin from the device tree on DT boot paths.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2013-12-20 11:41:30 +01:00
Boris BREZILLON
8be3da65d9 tty/serial: at91: document clock properties
Document the clock properties required by the at91 usart driver.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:38:25 -08:00
Kumar Gala
6b9c1fa25a serial: unify serial bindings into a single dir
Move all bindings in bindings/tty/serial into bindings/serial so we only
have one place dir with serial/uart related bindings in it.

Signed-off-by: Kumar Gala <galak@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-28 16:02:48 -07:00