This converts the Freescale SPI master driver to use GPIO
descriptors for chip select handling.

The Freescale (fsl) driver has a lot of quirks to look up
"gpios" rather than "cs-gpios" from the device tree.
After the prior patch that will make gpiolib return the
GPIO descriptor for "gpios" in response to a request for
"cs-gpios", this code can be cut down quite a bit.

The driver has custom handling of chip select rather
than using the core (which may be possible but not
done in this patch) so it still needs to refer directly
to spi->cs_gpiod to set the chip select.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190804003539.985-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

On platforms like LS1021A which use TCFQ mode, an interrupt needs to be
processed after each byte is TXed/RXed. I tried to make the DSPI
implementation on this SoC operate in other, more efficient modes (EOQ,
DMA) but it looks like it simply isn't possible.

Therefore allow the driver to operate in poll mode, to ease a bit of
this absurd amount of IRQ load generated in TCFQ mode. Doing so reduces
both the net time it takes to transmit a SPI message, as well as the
inter-frame jitter that occurs while doing so.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190822211514.19288-5-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

dspi->devtype_data is under the total control of the driver. Therefore,
a bad value is a driver bug and checking it at runtime (and during an
ISR, at that!) is pointless.

The second "else if" check is only for clarity (instead of a broader
"else") in case other transfer modes are added in the future. But the
printing is dead code and can be removed.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190822211514.19288-4-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

The DSPI interrupt can be shared between two controllers at least on the
LX2160A. In that case, the driver for one controller might misbehave and
consume the other's interrupt. Fix this by actually checking if any of
the bits in the status register have been asserted.

Fixes: 13aed239 ("spi: spi-fsl-dspi: use IRQF_SHARED mode to request IRQ")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190822211514.19288-3-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

If the entire function depends on the SPI status register having the
interrupt bits asserted, then just check it and exit early if those bits
aren't set (such as in the case of the shared IRQ being triggered for
the other peripheral). Cosmetic patch.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190822211514.19288-2-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

The DSPI interrupt can be shared between two controllers at least on the
LX2160A. In that case, the driver for one controller might misbehave and
consume the other's interrupt. Fix this by actually checking if any of
the bits in the status register have been asserted.

Fixes: 13aed239 ("spi: spi-fsl-dspi: use IRQF_SHARED mode to request IRQ")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190822212450.21420-2-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

There are 2 version of QSPI-IP, according to which controller registers sets
can be big endian or little endian.There are some other minor changes like
RX fifo depth etc.

The big endian version uses driver compatible "fsl,ls1021a-qspi" and
little endian version uses driver compatible "fsl,ls2080a-qspi"
Signed-off-by: Kuldeep Singh <kuldeep.singh@nxp.com>
Signed-off-by: Ashish Kumar <ashish.kumar@nxp.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/1565691791-26167-1-git-send-email-Ashish.Kumar@nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>

Add example for adding flash entry on various boards' dts
using flash manufacture spansion/cypress.
Signed-off-by: Ashish Kumar <Ashish.Kumar@nxp.com>
Link: https://lore.kernel.org/r/1565691791-26167-3-git-send-email-Ashish.Kumar@nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>

The two functions are loosely coupled through dspi->waitq, but
logically, dspi_transfer_one_message depends on dspi_interrupt in order
to complete. Move its definition above it so the I/O functions are
grouped closer together.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-13-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

mask of -> mask off
at and -> and
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-12-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

This patch puts variable declaration in the reverse order of their
length for cosmetic purposes.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-11-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

This adapts the spi-fsl-dspi driver to the API changes introduced in
commit 8caab75f ("spi: Generalize SPI "master" to "controller"").
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-10-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

Introduced in commit 9298bc72 ("spi: spi-fsl-dspi: Remove
spi-bitbang") for less than obvious reasons, this assignment is
confusing and serves no purpose.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-9-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

There is no code path for reaching 'return ret;' without it first being
assigned to an error code. Therefore the initialization with 0 is
pointless.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-8-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

There is no point in surrounding an entire function block in an if
condition. Rather, exit early if the condition is false.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-7-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

These are macros that accept 0 or 1 as argument (a boolean value). Their
use encourages the abuse of complex ternary operations inside their
argument list, which detracts from the code readability. Replace these
with simple if-else statements.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-6-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

This patch adds the field definitions for the SPI_SR register. The SPI
status register is write-1-to-clear and this value is written at init
time.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-5-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

Switch to using more idiomatic register field definitions, which makes
it easier to look them up in the datasheet. Cosmetic patch.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-4-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

This is a cosmetic patch.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-3-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

This is a cosmetic patch that changes nothing except makes sure the code
is aligned to the same column, which makes it easier to the eye.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20190818180115.31114-2-olteanv@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

The number of CS lines is mentioned as 2 in the spi-controller binding
but however in the example, 4 cs-gpios are used. Hence fix that to
mention 4.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20190820115000.32041-1-manivannan.sadhasivam@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Use devm_spi_register_controller to fix missing spi_unregister_controller
when unload module.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/20190818095113.2397-1-axel.lin@ingics.comSigned-off-by: Mark Brown <broonie@kernel.org>

Add support for Intel(R) Programmable Services Engine (Intel(R) PSE) SPI
controller in Intel Elkhart Lake when interface is assigned to the host
processor.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20190812101344.3975-1-jarkko.nikula@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

Rename this function to of_spi_get_gpio_numbers() as this
is what the function does, it does not register a master,
it is called in the path of registering a master so the
name is logical in a convoluted way, but it is better to
follow Rusty Russell's ABI level no 7:
"The obvious use is (probably) the correct one"
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190808150321.23319-1-linus.walleij@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Use the devm_platform_ioremap_resource() helper instead of open-coding
the same operation.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20190807085213.24666-1-geert+renesas@glider.beSigned-off-by: Mark Brown <broonie@kernel.org>

Fix data transfer width settings based on DT field 'spi-rx-bus-width'
to configure BSPI in single, dual or quad mode by using data width
and not the command width.

Fixes: 5f195ee7 ("spi: bcm-qspi: Implement the spi_mem interface")
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Link: https://lore.kernel.org/r/1565086070-28451-1-git-send-email-rayagonda.kokatanur@broadcom.comSigned-off-by: Mark Brown <broonie@kernel.org>

Driver specific implementations for .transfer_one_message need to call
the tracing stuff themself. This is necessary to make spi tracing
actually useful.
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Link: https://lore.kernel.org/r/20190801204710.27309-1-uwe@kleine-koenig.orgSigned-off-by: Mark Brown <broonie@kernel.org>

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-42-swboyd@chromium.orgSigned-off-by: Mark Brown <broonie@kernel.org>

The SPI thingies request FIFO-99 by default, reduce this to FIFO-50.

FIFO-99 is the very highest priority available to SCHED_FIFO and
it not a suitable default; it would indicate the SPI work is the
most important work on the machine.

Cc: Benson Leung <bleung@chromium.org>
Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20190801111541.917256884@infradead.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Intel Tiger Lake -LP LPSS SPI controller is otherwise similar than
Cannon Lake but has more controllers and up to two chip selects per
controller.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Link: https://lore.kernel.org/r/20190801134901.12635-1-jarkko.nikula@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

Convert the SPI slave control sysfs attribute from DEVICE_ATTR() to
DEVICE_ATTR_RW(), to reduce boilerplate.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20190731124738.14519-1-geert+renesas@glider.beSigned-off-by: Mark Brown <broonie@kernel.org>

No need to add hardware spinlock proctection due to add multiple
msater channel, so change it to be optional in documentation.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/23d51f5d9c9cc647ad0c5a1fb950d3d9fb9c1303.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Now Spreadtrum ADI controller supplies multiple master accessing channel
to support multiple subsystems accessing, instead of using a hardware
spinlock to synchronize between the multiple subsystems.

To keep backward compatibility, we should change the hardware spinlock
to be optional. Moreover change to use of_hwspin_lock_get_id() function
which return -ENOENT error number to indicate no hwlock support.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/2abe7dcf210e4197f8c5ece7fc6d6cc1eda8c655.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

When the system was rebooted by watchdog, now we did not save the watchdog
reset mode which will make system enter a incorrect mode after rebooting.

Thus we should set the watchdog reset mode as default when opening the
watchdog configuration, that means if the system was rebooted by other
reason through the restart_handler(), then we will clear the default
watchdog reset mode to save the correct reset mode.
Signed-off-by: Sherry Zong <sherry.zong@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/1563f3de43c6c2262d597a25d6138b5de61ea23d.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Add a new reset flag to indicate that the system need enter factory test
mode after restarting system.
Signed-off-by: Sherry Zong <sherry.zong@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/8ae5651e876b527920ff878721a8a8ef47b099ac.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Add a new reset flag to indicate the reset reason is caused by TOS.
Signed-off-by: Chenxu Wei <weicx@spreadst.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/97583aad1f2b849d69b4e76e8d29113da72a9fff.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

The ADI default transfer address bits is 12bit on Spreadtrum SC9860
platform, thus there is no need to set again, remove it.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/3cb57b8aadb7747a9f833e9b4fe8596ba738d9f6.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Commit 6935224d ("spi: bcm2835: enable support of 3-wire mode")
added 3-wire support to the BCM2835 SPI driver by setting the REN bit
(Read Enable) in the CS register when receiving data.  The REN bit puts
the transmitter in high-impedance state.  The driver recognizes that
data is to be received by checking whether the rx_buf of a transfer is
non-NULL.

Commit 3ecd37ed ("spi: bcm2835: enable dma modes for transfers
meeting certain conditions") subsequently broke 3-wire support because
it set the SPI_MASTER_MUST_RX flag which causes spi_map_msg() to replace
rx_buf with a dummy buffer if it is NULL.  As a result, rx_buf is
*always* non-NULL if DMA is enabled.

Reinstate 3-wire support by not only checking whether rx_buf is non-NULL,
but also checking that it is not the dummy buffer.

Fixes: 3ecd37ed ("spi: bcm2835: enable dma modes for transfers meeting certain conditions")
Reported-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.2+
Cc: Martin Sperl <kernel@martin.sperl.org>
Acked-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/328318841455e505370ef8ecad97b646c033dc8a.1562148527.git.lukas@wunner.deSigned-off-by: Mark Brown <broonie@kernel.org>

Instead of using to_pci_dev + pci_get_drvdata,
use dev_get_drvdata to make code simpler.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Link: https://lore.kernel.org/r/20190724122331.21856-1-hslester96@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>