If PM_RUNTIME is enabled, it is easy to trigger the following backtrace
on pxa2xx hosts:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at /home/lumag/linux/arch/arm/mach-pxa/clock.c:35 clk_disable+0xa0/0xa8()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00007-g1b3d2ee-dirty #104
[<c000de68>] (unwind_backtrace) from [<c000c078>] (show_stack+0x10/0x14)
[<c000c078>] (show_stack) from [<c001d75c>] (warn_slowpath_common+0x6c/0x8c)
[<c001d75c>] (warn_slowpath_common) from [<c001d818>] (warn_slowpath_null+0x1c/0x24)
[<c001d818>] (warn_slowpath_null) from [<c0015e80>] (clk_disable+0xa0/0xa8)
[<c0015e80>] (clk_disable) from [<c02507f8>] (pxa2xx_spi_suspend+0x2c/0x34)
[<c02507f8>] (pxa2xx_spi_suspend) from [<c0200360>] (platform_pm_suspend+0x2c/0x54)
[<c0200360>] (platform_pm_suspend) from [<c0207fec>] (dpm_run_callback.isra.14+0x2c/0x74)
[<c0207fec>] (dpm_run_callback.isra.14) from [<c0209254>] (__device_suspend+0x120/0x2f8)
[<c0209254>] (__device_suspend) from [<c0209a94>] (dpm_suspend+0x50/0x208)
[<c0209a94>] (dpm_suspend) from [<c00455ac>] (suspend_devices_and_enter+0x8c/0x3a0)
[<c00455ac>] (suspend_devices_and_enter) from [<c0045ad4>] (pm_suspend+0x214/0x2a8)
[<c0045ad4>] (pm_suspend) from [<c04b5c34>] (test_suspend+0x14c/0x1dc)
[<c04b5c34>] (test_suspend) from [<c000880c>] (do_one_initcall+0x8c/0x1fc)
[<c000880c>] (do_one_initcall) from [<c04aecfc>] (kernel_init_freeable+0xf4/0x1b4)
[<c04aecfc>] (kernel_init_freeable) from [<c0378078>] (kernel_init+0x8/0xec)
[<c0378078>] (kernel_init) from [<c0009590>] (ret_from_fork+0x14/0x24)
---[ end trace 46524156d8faa4f6 ]---

This happens because suspend function tries to disable a clock that is
already disabled by runtime_suspend callback. Add if
(!pm_runtime_suspended()) checks to suspend/resume path.

Fixes: 7d94a505 (spi/pxa2xx: add support for runtime PM)
Signed-off-by: NDmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Reported-by: NAndrea Adami <andrea.adami@gmail.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

Signed-off-by: NMichael Heimpold <mhei@heimpold.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

Though intel-mid-dma does not follow a new DMA workflow (*) let's prepare SPI
DW driver for that.

(*) The client is obliged to call dma_async_issue_pending() which starts the
actual transfers. Old DMA drivers do not follow this, since requirement was
introduced in the discussion of [1].

[1] http://www.spinics.net/lists/arm-kernel/msg125987.htmlSigned-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Instead of direct dereference to dmaengine callbacks we are going to use
DMAengine wrappers.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Instead of using magic numbers in the code we create a bit map definition of
the DMACR register and use it.

There is no functional change.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The Armada SoC family implementation of this SPI hardware module has
extended the configuration register to allow for a wider range of SPI
clock rates. Specifically the Serial Baud Rate Pre-selection bits in the
SPI Interface Configuration Register now also use bits 6 and 7 as well.

Modify the baud rate calculation to handle these differences for the
Armada case. Potentially a baud rate can be setup using a number of
different pre-scalar and scalar combinations. This code tries all
possible pre-scalar divisors (8 in total) to try and find the most
accurate set.

This change introduces (and documents) a new device tree compatible
device name "armada-370-spi" to support this.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Tested-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Reviewed-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The commit 46420dd7 (PM / Domains: Add APIs to attach/detach a PM
domain for a device) started using errno values in pm.h header file.
It also failed to include the header for these, thus it caused
compiler errors.

Instead of including the errno header to pm.h, let's move the functions
to pm_domain.h, since it's a better match.

Fixes: 46420dd7 (PM / Domains: Add APIs to attach/detach a PM domain for a device)
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Sort all the include headers alphabetically for the freescale
spi drivers. If the inlcude headers sorted out of order, maybe
the best logical choice is to append new ones after the exist
ones, while this may create a lot of potential for duplicates
and conflicts for each diffenent changes will add new headers
in the same location.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Mainly to fix missing MODULE_LICENSE.
Also add MODULE_DESCRIPTION and MODULE_AUTHOR.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

config SPI_BCM53XX needs to depend on BCMA_POSSIBLE and select BCMA.
This fixes below build error:
ERROR: "bcma_driver_unregister" [drivers/spi/spi-bcm53xx.ko] undefined!
ERROR: "__bcma_driver_register" [drivers/spi/spi-bcm53xx.ko] undefined!
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

In my test on RK3288-pinky board, if spi is enabled, it will begin to
read data from slave regardless of whether the DMA is ready. So we
need prepare DMA before spi is enable.
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

Remove the probe info message which also has wrong output. No need to add
KERN_INFO to pr_info. Output was:
6Freescale DSPI master initialized
Signed-off-by: NAlexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Add support for a extended PL022 which has an extra register for controlling up
to five chip select signals. This controller is found on the AXM5516 SoC.
Unfortunately the PrimeCell identification registers are identical to a
standard ARM PL022. To work around this, the peripheral ID must be overridden
in the device tree using the "arm,primecell-periphid" property with the value
0x000b6022.
Signed-off-by: NAnders Berg <anders.berg@avagotech.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NMark Brown <broonie@kernel.org>

Since we cannot make sure the 'n' will always be none zero here, and
then if either equal to zero, the kzalloc() will return ZERO_SIZE_PTR,
which equals to ((void *)16).

So this patch fix this with just doing the zero check before calling
kzalloc().
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Make comments be surrounded by spaces and move part of code to one line where
it suits 80 characters.

There is no functional changes.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

For testing purposes it's good to have a loopback mode enabled. The patch adds
necessary bits for that.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Do full clean up at exit, means terminate all ongoing DMA transfers.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

In case of 8 bit mode and DMA usage we end up with every second byte written as
0. We have to respect bits_per_word settings what this patch actually does.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

Currently clps711x arch have a fully functional CLK driver.
This patch migrates clps711x-spi driver to use the new CLK subsystem.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NMark Brown <broonie@kernel.org>

Previously only the ACPI PM domain was supported by the spi bus.

Let's convert to the common attach/detach functions for PM domains,
which currently means we are extending the support to include the
generic PM domain as well.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NKevin Hilman <khilman@linaro.org>
Reviewed-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently this driver is missing a check on the return value of devm_kzalloc,
which would cause a NULL pointer dereference in a OOM situation.

This patch adds a missing check.
Signed-off-by: NKiran Padwal <kiran.padwal@smartplayin.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Instead of one port we have 3 ports and all of them can take advantage of
the shared DMA controller.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NMark Brown <broonie@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

That field has been deprecated in favour of getting the necessary
information from ACPI/DT.

However, we still need to deal systems that are PCI only (no ACPI to back
up). In order to support such systems, we allow the DMA filter function and
its corresponding parameter via pxa2xx_spi_master platform data. Then when
the pxa2xx_spi_dma_setup() doesn't find the channel via ACPI, it falls back
to use the given filter function.
Suggested-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NMark Brown <broonie@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Enable DMA support on i.mx6. The read speed can increase from 600KB/s
to 1.2MB/s on i.mx6q. You can disable or enable dma function in dts.
If not set "dma-names" in dts, spi will use PIO mode. This patch only
validate on i.mx6, not i.mx5, but encourage ones to apply this patch
on i.mx5 since they share the same IP.

Note:
  Sometime, there is a weid data in rxfifo after one full tx/rx
transfer finish by DMA on i.mx6dl, so we disable dma functhion on
i.mx6dl.
Signed-off-by: NFrank Li <Frank.Li@freescale.com>
Signed-off-by: NRobin Gong <b38343@freescale.com>
Acked-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch adds ability to configure delay between transmission of
words over SPI bus if it's required by SPI slave devices.

New optional SPI slave property:
- ti,spi-word-delay : delay between transmission of words
	(SPIFMTn.WDELAY, SPIDAT1.WDEL)
Signed-off-by: NMurali Karicheri <m-karicheri2@ti.com>
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Remove empty function davinci_spi_cleanup().
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Now CS GPIOs are requested from struct spi_master.setup() callback
and that causes failures when Client SPI device is getting accessed
through SPIDEV driver. The failure happens, because .setup() callback
may be called many times from IOCTL handler and when it's called
second time gpio_request() will fail and return -EBUSY.

Hence, fix it by moving CS GPIOs requesting code in .probe().
Reported-by: NMurali Karicheri <m-karicheri2@ti.com>
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Since driver is used on other platforms and debugfs stuff would be useful there
as well let's substitute mrst_ by dw_ where it suits. Additionally let's use
SPI master device name when print registers dump.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The FSF address is subject to change, thus remove it from the file. While here,
update a copyright line.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Instead of using that member we prefer to use dma_dev which represents actual
struct device of the DMA device.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

The support of the Moorestown was removed [1] from kernel long time ago. This
is just a follow up of that change.

[1] http://www.spinics.net/lists/platform-driver-x86/msg02948.htmlSigned-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

If the driver was compiled with DMA support, but DMA channels weren't acquired
by some reason, mid_spi_dma_exit() will crash the kernel.

Fixes: 7063c0d9 (spi/dw_spi: add DMA support)
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

There is no need to keep FSF address in the head of the file. While here, fix
few typos in the header.

There is no functional change.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch fixes an error message typo ("not" missing).
Signed-off-by: NRoland Stigge <stigge@antcom.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

The reference manual from Rockchip claims this about the BSF (SPI Busy
Flag):
* 0 - SPI is idle or disabled
* 1 - SPI is actively transferring data

The above doesn't quite appear to be true.  Specifically I found the
busy bit set when SPI was disabled.  Let's change the WARN_ON() so we
only check the busy bit if the controller was enabled.
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

The wait_for_idle() could get unlucky and timeout too quickly.
Specifically, the old calculation was effectively:
  timeout = jiffies + 1;
  if (jiffies >= timeout) print warning;

From the above it should be obvious that if jiffies ticks in just the
wrong place then we'll have an effective timeout of 0.

Fix this by effectively changing the above ">=" to a ">".  That gives
us an extra jiffy to finish.
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

let "#define" statement keep same indentation. the old code layout is
pretty ugly.
Signed-off-by: NQipan Li <Qipan.Li@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

for command mode spi transfer, HW spec requires to do fifo reset work to
clear FIFO status.
Signed-off-by: NQipan Li <Qipan.Li@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

unify 'cmd_transfer' like 'pio_transfer' and 'dma_transfer' as void
function, and also change left_rx_word according to transfer result.
Signed-off-by: NQipan Li <Qipan.Li@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

in spi interrupt handler, we need check RX_IO_DMA status to ensure
rx fifo have received the specify count data.

if not set, the while statement in spi isr function will keep loop,
at last, make the kernel hang.

[The code is actually there in the interrupt handler but apparently it
needs the interrupt unmasking so the handler sees the status -- broonie]
Signed-off-by: NQipan Li <Qipan.Li@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org