Commit Graph

376 Commits

Author SHA1 Message Date
Geert Uytterhoeven
1723fdec5f
spi: Add missing error handling for CS GPIOs
While devm_gpiod_get_index_optional() returns NULL if the GPIO is not
present (i.e. -ENOENT), it may still return other error codes, like
-EPROBE_DEFER.  Currently these are not handled, leading to
unrecoverable failures later in case of probe deferral:

    gpiod_set_consumer_name: invalid GPIO (errorpointer)
    gpiod_direction_output: invalid GPIO (errorpointer)
    gpiod_set_value_cansleep: invalid GPIO (errorpointer)
    gpiod_set_value_cansleep: invalid GPIO (errorpointer)
    gpiod_set_value_cansleep: invalid GPIO (errorpointer)

Detect and propagate errors to fix this.

Fixes: f3186dd876 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-04 12:58:18 +07:00
Chris Lesiak
5442dcaa0d
spi: Fix zero length xfer bug
This fixes a bug for messages containing both zero length and
unidirectional xfers.

The function spi_map_msg will allocate dummy tx and/or rx buffers
for use with unidirectional transfers when the hardware can only do
a bidirectional transfer.  That dummy buffer will be used in place
of a NULL buffer even when the xfer length is 0.

Then in the function __spi_map_msg, if he hardware can dma,
the zero length xfer will have spi_map_buf called on the dummy
buffer.

Eventually, __sg_alloc_table is called and returns -EINVAL
because nents == 0.

This fix prevents the error by not using the dummy buffer when
the xfer length is zero.

Signed-off-by: Chris Lesiak <chris.lesiak@licor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-11 16:40:00 +00:00
Felix Fietkau
28f7604f48
spi: use gpio[d]_set_value_cansleep for setting chipselect GPIO
Sleeping is safe inside spi_transfer_one_message, and some
GPIO chips are running on slow busses (such as I2C GPIO
expanders) and need to sleep for setting values.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-02-12 16:41:11 +00:00
Jonas Bonn
b7bb367afa
spi: support inter-word delay requirement for devices
Some devices are slow and cannot keep up with the SPI bus and therefore
require a short delay between words of the SPI transfer.

The example of this that I'm looking at is a SAMA5D2 with a minimum SPI
clock of 400kHz talking to an AVR-based SPI slave.  The AVR cannot put
bytes on the bus fast enough to keep up with the SoC's SPI controller
even at the lowest bus speed.

This patch introduces the ability to specify a required inter-word
delay for SPI devices.  It is up to the controller driver to configure
itself accordingly in order to introduce the requested delay.

Note that, for spi_transfer, there is already a field word_delay that
provides similar functionality.  This field, however, is specified in
clock cycles (and worse, SPI controller cycles, not SCK cycles); that
makes this value dependent on the master clock instead of the device
clock for which the delay is intended to provide some relief.  This
patch leaves this old word_delay in place and provides a time-based
word_delay_us alongside it; the new field fits in the struct padding
so struct size is constant.  There is only one in-kernel user of the
word_delay field and presumably that driver could be reworked to use
the time-based value instead.

The time-based delay is limited to 8 bits as these delays are intended
to be short.  The SAMA5D2 that I've tested this on limits delays to a
maximum of ~100us, which is already many word-transfer periods even at
the minimum transfer speed supported by the controller.

Signed-off-by: Jonas Bonn <jonas@norrbonn.se>
CC: Mark Brown <broonie@kernel.org>
CC: Rob Herring <robh+dt@kernel.org>
CC: Mark Rutland <mark.rutland@arm.com>
CC: linux-spi@vger.kernel.org
CC: devicetree@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-30 23:02:10 +00:00
Linus Walleij
2df201e006
spi: Support high CS when using descriptors
All controllers using GPIO descriptors can by definition
support high CS connections, so just enforce this when
registering an SPI controller.

This fixes a regression where controllers were missing
SPI_CS_HIGH, the drivers would fail like this:

spi spi0.0: setup: unsupported mode bits 4
cdns-spi fd0b0000.spi: can't setup spi0.0, status -22

This is because as using descriptors moves the CS inversion
logic over to gpiolib, all such controllers are registered
with CS active high.

Cc: Jan Kotas <jank@cadence.com>
Reported-by: Jan Kotas <jank@cadence.com>
Tested-by: Jan Kotas <jank@cadence.com>
Fixes: f3186dd876 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-24 19:01:05 +00:00
Mark Brown
f0125f1a55
spi: Go back to immediate teardown
Commit 412e603732 ("spi: core: avoid waking pump thread from spi_sync
instead run teardown delayed") introduced regressions on some boards,
apparently connected to spi_mem not triggering shutdown properly any
more.  Since we've thus far been unable to figure out exactly where the
breakage is revert the optimisation for now.

Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: kernel@martin.sperl.org
2019-01-23 17:29:53 +00:00
Martin Sperl
412e603732
spi: core: avoid waking pump thread from spi_sync instead run teardown delayed
When spi_sync is running alone with no other spi devices connected
to the bus the worker thread is woken during spi_finalize_current_message
to run the teardown code every time.

This is totally unnecessary in the case that there is no message queued.

On a multi-core system this results in one wakeup of the thread for each
spi_message processed via spi_sync where in most cases the teardown does
not happen as the hw is already in use.

This patch now delays the teardown by 1 second by using a separate
kthread_delayed_work for the teardown.

This avoids waking the kthread too often.

For spi_sync transfers in a tight loop (say 40k messages/s) this
avoids the penalty of waking the worker thread 40k times/s.
On a rasperry pi 3 with 4 cores the results in 32% of a single core
only to find out that there is nothing in the queue and it can go back
to sleep.

With this patch applied the spi-worker is woken exactly once: after
the load finishes and the spi bus is idle for 1 second.

I believe I have also seen situations where during a spi_sync loop
the worker thread (triggered by the last message finished) is slightly
faster and _wins_ the race to process the message, so we are actually
running the kthread and letting it do some work...

This is also no longer observed with this patch applied as.

Tested with a new CAN controller driver for the mcp2517fd which
uses spi_sync for interrupt handling and spi_async for scheduling
of can frames for transmission (in a different thread)

Some statistics when receiving 100000 CAN frames with the mcp25xxfd driver
on a Raspberry pi 3:

without the patch:
------------------
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                    5
(irq/94-mcp25xxf)         0
root@raspcm3:~# vmstat 1
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
 1  0      0 821960  13592  50848    0    0    80     2 1986  105  1  2 97  0  0
 0  0      0 821968  13592  50876    0    0     0     0 8046   30  0  0 100  0  0
 0  0      0 821936  13592  50876    0    0     0     0 8032   24  0  0 100  0  0
 0  0      0 821936  13592  50876    0    0     0     0 8035   30  0  0 100  0  0
 0  0      0 821936  13592  50876    0    0     0     0 8033   22  0  0 100  0  0
 2  0      0 821936  13592  50876    0    0     0     0 11598 7129  0  3 97  0  0
 1  0      0 821872  13592  50876    0    0     0     0 37741 59003  0 31 69  0  0
 2  0      0 821840  13592  50876    0    0     0     0 37762 59078  0 29 71  0  0
 2  0      0 821776  13592  50876    0    0     0     0 37593 58792  0 28 72  0  0
 1  0      0 821744  13592  50876    0    0     0     0 37642 58881  0 30 70  0  0
 2  0      0 821680  13592  50876    0    0     0     0 37490 58602  0 27 73  0  0
 1  0      0 821648  13592  50876    0    0     0     0 37412 58418  0 29 71  0  0
 1  0      0 821584  13592  50876    0    0     0     0 37337 58288  0 27 73  0  0
 1  0      0 821552  13592  50876    0    0     0     0 37584 58774  0 27 73  0  0
 0  0      0 821520  13592  50876    0    0     0     0 18363 20566  0  9 91  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8037   32  0  0 100  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8031   23  0  0 100  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8034   26  0  0 100  0  0
 0  0      0 821520  13592  50876    0    0     0     0 8033   24  0  0 100  0  0
^C
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                  228
(irq/94-mcp25xxf)       794
root@raspcm3:~# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
 17:         34          0          0          0  ARMCTRL-level   1 Edge      3f00b880.mailbox
 27:          1          0          0          0  ARMCTRL-level  35 Edge      timer
 33:    1416870          0          0          0  ARMCTRL-level  41 Edge      3f980000.usb, dwc2_hsotg:usb1
 34:          1          0          0          0  ARMCTRL-level  42 Edge      vc4
 35:          0          0          0          0  ARMCTRL-level  43 Edge      3f004000.txp
 40:       1753          0          0          0  ARMCTRL-level  48 Edge      DMA IRQ
 42:         11          0          0          0  ARMCTRL-level  50 Edge      DMA IRQ
 44:         11          0          0          0  ARMCTRL-level  52 Edge      DMA IRQ
 45:          0          0          0          0  ARMCTRL-level  53 Edge      DMA IRQ
 66:          0          0          0          0  ARMCTRL-level  74 Edge      vc4 crtc
 69:          0          0          0          0  ARMCTRL-level  77 Edge      vc4 crtc
 70:          0          0          0          0  ARMCTRL-level  78 Edge      vc4 crtc
 77:         20          0          0          0  ARMCTRL-level  85 Edge      3f205000.i2c, 3f804000.i2c, 3f805000.i2c
 78:       6346          0          0          0  ARMCTRL-level  86 Edge      3f204000.spi
 80:        205          0          0          0  ARMCTRL-level  88 Edge      mmc0
 81:        493          0          0          0  ARMCTRL-level  89 Edge      uart-pl011
 89:          0          0          0          0  bcm2836-timer   0 Edge      arch_timer
 90:       4291       3821       2180       1649  bcm2836-timer   1 Edge      arch_timer
 94:      14289          0          0          0  pinctrl-bcm2835  16 Level     mcp25xxfd
IPI0:          0          0          0          0  CPU wakeup interrupts
IPI1:          0          0          0          0  Timer broadcast interrupts
IPI2:       3645     242371       7919       1328  Rescheduling interrupts
IPI3:        112        543        273        194  Function call interrupts
IPI4:          0          0          0          0  CPU stop interrupts
IPI5:          1          0          0          0  IRQ work interrupts
IPI6:          0          0          0          0  completion interrupts
Err:          0

top shows 93% for the mcp25xxfd interrupt handler, 31% for spi0.

with the patch:
---------------
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                    0
(irq/94-mcp25xxf)         0
root@raspcm3:~# vmstat 1
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
 0  0      0 804768  13584  62628    0    0     0     0 8038   24  0  0 100  0  0
 0  0      0 804768  13584  62628    0    0     0     0 8042   25  0  0 100  0  0
 1  0      0 804704  13584  62628    0    0     0     0 9603 2967  0 20 80  0  0
 1  0      0 804672  13584  62628    0    0     0     0 9828 3380  0 24 76  0  0
 1  0      0 804608  13584  62628    0    0     0     0 9823 3375  0 23 77  0  0
 1  0      0 804608  13584  62628    0    0     0    12 9829 3394  0 23 77  0  0
 1  0      0 804544  13584  62628    0    0     0     0 9816 3362  0 22 78  0  0
 1  0      0 804512  13584  62628    0    0     0     0 9817 3367  0 23 77  0  0
 1  0      0 804448  13584  62628    0    0     0     0 9822 3370  0 22 78  0  0
 1  0      0 804416  13584  62628    0    0     0     0 9815 3367  0 23 77  0  0
 0  0      0 804352  13584  62628    0    0     0    84 9222 2250  0 14 86  0  0
 0  0      0 804352  13592  62620    0    0     0    24 8131  209  0  0 93  7  0
 0  0      0 804320  13592  62628    0    0     0     0 8041   27  0  0 100  0  0
 0  0      0 804352  13592  62628    0    0     0     0 8040   26  0  0 100  0  0
root@raspcm3:~# for x in $(pgrep spi0) $(pgrep irq/94-mcp25xxf) ; do awk '{printf "%-20s %6i\n", $2,$15}' /proc/$x/stat; done
(spi0)                    0
(irq/94-mcp25xxf)       767
root@raspcm3:~# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
 17:         29          0          0          0  ARMCTRL-level   1 Edge      3f00b880.mailbox
 27:          1          0          0          0  ARMCTRL-level  35 Edge      timer
 33:    1024412          0          0          0  ARMCTRL-level  41 Edge      3f980000.usb, dwc2_hsotg:usb1
 34:          1          0          0          0  ARMCTRL-level  42 Edge      vc4
 35:          0          0          0          0  ARMCTRL-level  43 Edge      3f004000.txp
 40:       1773          0          0          0  ARMCTRL-level  48 Edge      DMA IRQ
 42:         11          0          0          0  ARMCTRL-level  50 Edge      DMA IRQ
 44:         11          0          0          0  ARMCTRL-level  52 Edge      DMA IRQ
 45:          0          0          0          0  ARMCTRL-level  53 Edge      DMA IRQ
 66:          0          0          0          0  ARMCTRL-level  74 Edge      vc4 crtc
 69:          0          0          0          0  ARMCTRL-level  77 Edge      vc4 crtc
 70:          0          0          0          0  ARMCTRL-level  78 Edge      vc4 crtc
 77:         20          0          0          0  ARMCTRL-level  85 Edge      3f205000.i2c, 3f804000.i2c, 3f805000.i2c
 78:       6417          0          0          0  ARMCTRL-level  86 Edge      3f204000.spi
 80:        237          0          0          0  ARMCTRL-level  88 Edge      mmc0
 81:        489          0          0          0  ARMCTRL-level  89 Edge      uart-pl011
 89:          0          0          0          0  bcm2836-timer   0 Edge      arch_timer
 90:       4048       3704       2383       1892  bcm2836-timer   1 Edge      arch_timer
 94:      14287          0          0          0  pinctrl-bcm2835  16 Level     mcp25xxfd
IPI0:          0          0          0          0  CPU wakeup interrupts
IPI1:          0          0          0          0  Timer broadcast interrupts
IPI2:       2361       2948       7890       1616  Rescheduling interrupts
IPI3:         65        617        301        166  Function call interrupts
IPI4:          0          0          0          0  CPU stop interrupts
IPI5:          1          0          0          0  IRQ work interrupts
IPI6:          0          0          0          0  completion interrupts
Err:          0
top shows 91% for the mcp25xxfd interrupt handler, 0% for spi0

So we see that spi0 is no longer getting scheduled wasting CPU cycles
There are a lot less context switches and corresponding Rescheduling interrupts
All of these show that this improves efficiency of the system and reduces
CPU utilization.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-09 19:16:18 +00:00
Linus Walleij
f3186dd876
spi: Optionally use GPIO descriptors for CS GPIOs
This augments the SPI core to optionally use GPIO descriptors
for chip select on a per-master-driver opt-in basis.

Drivers using this will rely on the SPI core to look up
GPIO descriptors associated with the device, such as
when using device tree or board files with GPIO descriptor
tables.

When getting descriptors from the device tree, this will in
turn activate the code in gpiolib that was
added in commit 6953c57ab1
("gpio: of: Handle SPI chipselect legacy bindings")
which means that these descriptors are aware of the active
low semantics that is the default for SPI CS GPIO lines
and we can assume that all of these are "active high" and
thus assign SPI_CS_HIGH to all CS lines on the DT path.

The previously used gpio_set_value() would call down into
gpiod_set_raw_value() and ignore the polarity inversion
semantics.

It seems like many drivers go to great lengths to set up the
CS GPIO line as non-asserted, respecting SPI_CS_HIGH. We pull
this out of the SPI drivers and into the core, and by simply
requesting the line as GPIOD_OUT_LOW when retrieveing it from
the device and relying on the gpiolib to handle any inversion
semantics. This way a lot of code can be simplified and
removed in each converted driver.

The end goal after dealing with each driver in turn, is to
delete the non-descriptor path (of_spi_register_master() for
example) and let the core deal with only descriptors.

The different SPI drivers have complex interactions with the
core so we cannot simply change them all over, we need to use
a stepwise, bisectable approach so that each driver can be
converted and fixed in isolation.

This patch has the intended side effect of adding support for
ACPI GPIOs as it starts relying on gpiod_get_*() to get
the GPIO handle associated with the device.

Cc: Linuxarm <linuxarm@huawei.com>
Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Fangjian (Turing) <f.fangjian@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-09 12:39:25 +00:00
Rob Herring
194276b073
spi: Use of_node_name_eq for node name comparisons
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-06 20:15:43 +00:00
Yogesh Narayan Gaur
6b03061f88
spi: add support for octal mode I/O data transfer
Add flags for Octal mode I/O data transfer
Required for the SPI controller which can do the data transfer (TX/RX)
on 8 data lines e.g. NXP FlexSPI controller.
 SPI_TX_OCTAL: transmit with 8 wires
 SPI_RX_OCTAL: receive with 8 wires

Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-03 17:14:53 +00:00
Mark Brown
787f4889a6
spi: Fix formatting of header block
Make everything look intentional by having a C++ comment for the whole
block, not just the SPDX line.

Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-29 16:24:37 +00:00
Mark Brown
d57e79601b
spi: Fix core transfer waits after slave support
The refactoring done as part of adding the core support for handling
waiting for slave transfer dropped a conditional which meant that we
started waiting for completion of all transfers, not just those that the
controller asked for.  This caused hangs and massive delays on platforms
that don't need the core delay.  Re-add the delay to fix this.

Fixes: 810923f3bf (spi: Deal with slaves that return from transfer_one() unfinished)
Reported-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15 16:08:32 -08:00
Lubomir Rintel
810923f3bf
spi: Deal with slaves that return from transfer_one() unfinished
Some drivers, such as spi-pxa2xx return from the transfer_one callback
immediately, idicating that the transfer will be finished asynchronously.

Normally, spi_transfer_one_message() synchronously waits for the
transfer to finish with wait_for_completion_timeout(). For slaves, we
don't want the transaction to time out as it can complete in a long time
in future. Use wait_for_completion_interruptible() instead.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-13 10:01:23 -08:00
Mark Brown
7b9734dbc5
Merge remote-tracking branch 'spi/topic/of' into spi-next 2018-10-21 17:00:17 +01:00
Mark Brown
4b51c747e4
Merge branch 'spi-4.20' into spi-next 2018-10-21 17:00:14 +01:00
Phil Elwell
25972d0c33
spi: Make GPIO CSs honour the SPI_NO_CS flag
The SPI configuration state includes an SPI_NO_CS flag that disables
all CS line manipulation, for applications that want to manage their
own chip selects. However, this flag is ignored by the GPIO CS code
in the SPI framework.

Correct this omission with a trivial patch.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-12 18:47:28 +02:00
Trent Piepho
5039563e7c
spi: Add driver_override SPI device attribute
This attribute works the same was as the identically named attribute
for PCI, AMBA, and platform devices.  For reference, see:

commit 3cf3857134 ("ARM: 8256/1: driver coamba: add device binding
path 'driver_override'")
commit 3d713e0e38 ("driver core: platform: add device binding path
'driver_override'")
commit 782a985d7a ("PCI: Introduce new device binding path using
pci_dev.driver_override")

If the name of a driver is written to this attribute, then the device
will bind to the named driver and only the named driver.

The device will bind to the driver even if the driver does not list the
device in its id table.  This behavior is different than the driver's
bind attribute, which only allows binding to devices that are listed as
supported by the driver.

It can be used to bind a generic driver, like spidev, to a device.

Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Tested-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-10 13:40:45 +01:00
Marco Felsch
5f143af750
spi: make OF helper available for others
The of_find_spi_device_by_node() helper function is useful for other
modules too. Export the funciton as GPL like all other spi helper
functions and make it available if CONFIG_OF is enabled, because it isn't
related to the CONFIG_OF_DYNAMIC context. Finally add a stub if
CONFIG_OF isn't enabled, so others must not care about it.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-27 23:36:03 +01:00
Marco Felsch
b445bfcb90
spi: switch to SPDX license identifier
Use the appropriate SPDX license identifier and drop the previous
license text.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-27 23:30:48 +01:00
David Lechner
71388b2156
spi: always use software fallback for SPI_CS_WORD when using cs_gio
This modifies the condition for using the software fallback
implementation for SPI_CS_WORD when the SPI controller is using a GPIO
for the CS line. When using a GPIO for CS, the hardware implementation
won't work, so we just enable the software fallback globally in this
case.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-18 10:40:32 -07:00
David Lechner
cbaa62e009
spi: add software implementation for SPI_CS_WORD
This adds a default software implementation for the SPI_CS_WORD flag for
controllers that don't have such a feature.

The SPI_CS_WORD flag indicates that the CS line should be toggled
between each word sent, not just between each transfer. The
implementation works by using existing functions to split transfers into
one-word-sized transfers and sets the cs_change bit for each of the
new transfers.

Signed-off-by: David Lechner <david@lechnology.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-09-17 14:14:18 -07:00
Geert Uytterhoeven
04b2d03a75
spi: Fix double IDR allocation with DT aliases
If the SPI bus number is provided by a DT alias, idr_alloc() is called
twice, leading to:

    WARNING: CPU: 1 PID: 1 at drivers/spi/spi.c:2179 spi_register_controller+0x11c/0x5d8
    couldn't get idr

Fix this by moving the handling of fixed SPI bus numbers up, before the
DT handling code fills in ctlr->bus_num.

Fixes: 1a4327fbf4 ("spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-28 20:46:27 +01:00
Kirill Kapranov
1a4327fbf4
spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers
On systems where some controllers get a dynamic ID assigned and some have
a fixed number (e.g. from ACPI tables), the current implementation might
run into an IDR collision: in case of a fixed bus number is gotten by a
driver (but not marked busy in IDR tree) and a driver with dynamic bus
number gets the same ID and predictably fails.

Fix this by means of checking-in fixed IDsin IDR as far as dynamic ones
at the moment of the controller registration.

Fixes: 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
Signed-off-by: Kirill Kapranov <kirill.kapranov@compulab.co.il>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2018-08-15 15:44:07 +01:00
Kees Cook
a86854d0c5 treewide: devm_kzalloc() -> devm_kcalloc()
The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

        devm_kzalloc(handle, a * b, gfp)

with:
        devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

        devm_kzalloc(handle, a * b * c, gfp)

with:

        devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  devm_kzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  devm_kzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
  devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * E2
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds
3c89adb0d1 Power management updates for 4.18-rc1
These include a significant update of the generic power domains (genpd)
 and Operating Performance Points (OPP) frameworks, mostly related to
 the introduction of power domain performance levels, cpufreq updates
 (new driver for Qualcomm Kryo processors, updates of the existing
 drivers, some core fixes, schedutil governor improvements), PCI power
 management fixes, ACPI workaround for EC-based wakeup events handling
 on resume from suspend-to-idle, and major updates of the turbostat
 and pm-graph utilities.
 
 Specifics:
 
  - Introduce power domain performance levels into the the generic
    power domains (genpd) and Operating Performance Points (OPP)
    frameworks (Viresh Kumar, Rajendra Nayak, Dan Carpenter).
 
  - Fix two issues in the runtime PM framework related to the
    initialization and removal of devices using device links (Ulf
    Hansson).
 
  - Clean up the initialization of drivers for devices in PM domains
    (Ulf Hansson, Geert Uytterhoeven).
 
  - Fix a cpufreq core issue related to the policy sysfs interface
    causing CPU online to fail for CPUs sharing one cpufreq policy in
    some situations (Tao Wang).
 
  - Make it possible to use platform-specific suspend/resume hooks
    in the cpufreq-dt driver and make the Armada 37xx DVFS use that
    feature (Viresh Kumar, Miquel Raynal).
 
  - Optimize policy transition notifications in cpufreq (Viresh Kumar).
 
  - Improve the iowait boost mechanism in the schedutil cpufreq
    governor (Patrick Bellasi).
 
  - Improve the handling of deferred frequency updates in the
    schedutil cpufreq governor (Joel Fernandes, Dietmar Eggemann,
    Rafael Wysocki, Viresh Kumar).
 
  - Add a new cpufreq driver for Qualcomm Kryo (Ilia Lin).
 
  - Fix and clean up some cpufreq drivers (Colin Ian King, Dmitry
    Osipenko, Doug Smythies, Luc Van Oostenryck, Simon Horman,
    Viresh Kumar).
 
  - Fix the handling of PCI devices with the DPM_SMART_SUSPEND flag
    set and update stale comments in the PCI core PM code (Rafael
    Wysocki).
 
  - Work around an issue related to the handling of EC-based wakeup
    events in the ACPI PM core during resume from suspend-to-idle if
    the EC has been put into the low-power mode (Rafael Wysocki).
 
  - Improve the handling of wakeup source objects in the PM core (Doug
    Berger, Mahendran Ganesh, Rafael Wysocki).
 
  - Update the driver core to prevent deferred probe from breaking
    suspend/resume ordering (Feng Kan).
 
  - Clean up the PM core somewhat (Bjorn Helgaas, Ulf Hansson, Rafael
    Wysocki).
 
  - Make the core suspend/resume code and cpufreq support the RT patch
    (Sebastian Andrzej Siewior, Thomas Gleixner).
 
  - Consolidate the PM QoS handling in cpuidle governors (Rafael
    Wysocki).
 
  - Fix a possible crash in the hibernation core (Tetsuo Handa).
 
  - Update the rockchip-io Adaptive Voltage Scaling (AVS) driver
    (David Wu).
 
  - Update the turbostat utility (fixes, cleanups, new CPU IDs, new
    command line options, built-in "Low Power Idle" counters support,
    new POLL and POLL% columns) and add an entry for it to MAINTAINERS
    (Len Brown, Artem Bityutskiy, Chen Yu, Laura Abbott, Matt Turner,
    Prarit Bhargava, Srinivas Pandruvada).
 
  - Update the pm-graph to version 5.1 (Todd Brandt).
 
  - Update the intel_pstate_tracer utility (Doug Smythies).
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Merge tag 'pm-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These include a significant update of the generic power domains
  (genpd) and Operating Performance Points (OPP) frameworks, mostly
  related to the introduction of power domain performance levels,
  cpufreq updates (new driver for Qualcomm Kryo processors, updates of
  the existing drivers, some core fixes, schedutil governor
  improvements), PCI power management fixes, ACPI workaround for
  EC-based wakeup events handling on resume from suspend-to-idle, and
  major updates of the turbostat and pm-graph utilities.

  Specifics:

   - Introduce power domain performance levels into the the generic
     power domains (genpd) and Operating Performance Points (OPP)
     frameworks (Viresh Kumar, Rajendra Nayak, Dan Carpenter).

   - Fix two issues in the runtime PM framework related to the
     initialization and removal of devices using device links (Ulf
     Hansson).

   - Clean up the initialization of drivers for devices in PM domains
     (Ulf Hansson, Geert Uytterhoeven).

   - Fix a cpufreq core issue related to the policy sysfs interface
     causing CPU online to fail for CPUs sharing one cpufreq policy in
     some situations (Tao Wang).

   - Make it possible to use platform-specific suspend/resume hooks in
     the cpufreq-dt driver and make the Armada 37xx DVFS use that
     feature (Viresh Kumar, Miquel Raynal).

   - Optimize policy transition notifications in cpufreq (Viresh Kumar).

   - Improve the iowait boost mechanism in the schedutil cpufreq
     governor (Patrick Bellasi).

   - Improve the handling of deferred frequency updates in the schedutil
     cpufreq governor (Joel Fernandes, Dietmar Eggemann, Rafael Wysocki,
     Viresh Kumar).

   - Add a new cpufreq driver for Qualcomm Kryo (Ilia Lin).

   - Fix and clean up some cpufreq drivers (Colin Ian King, Dmitry
     Osipenko, Doug Smythies, Luc Van Oostenryck, Simon Horman, Viresh
     Kumar).

   - Fix the handling of PCI devices with the DPM_SMART_SUSPEND flag set
     and update stale comments in the PCI core PM code (Rafael Wysocki).

   - Work around an issue related to the handling of EC-based wakeup
     events in the ACPI PM core during resume from suspend-to-idle if
     the EC has been put into the low-power mode (Rafael Wysocki).

   - Improve the handling of wakeup source objects in the PM core (Doug
     Berger, Mahendran Ganesh, Rafael Wysocki).

   - Update the driver core to prevent deferred probe from breaking
     suspend/resume ordering (Feng Kan).

   - Clean up the PM core somewhat (Bjorn Helgaas, Ulf Hansson, Rafael
     Wysocki).

   - Make the core suspend/resume code and cpufreq support the RT patch
     (Sebastian Andrzej Siewior, Thomas Gleixner).

   - Consolidate the PM QoS handling in cpuidle governors (Rafael
     Wysocki).

   - Fix a possible crash in the hibernation core (Tetsuo Handa).

   - Update the rockchip-io Adaptive Voltage Scaling (AVS) driver (David
     Wu).

   - Update the turbostat utility (fixes, cleanups, new CPU IDs, new
     command line options, built-in "Low Power Idle" counters support,
     new POLL and POLL% columns) and add an entry for it to MAINTAINERS
     (Len Brown, Artem Bityutskiy, Chen Yu, Laura Abbott, Matt Turner,
     Prarit Bhargava, Srinivas Pandruvada).

   - Update the pm-graph to version 5.1 (Todd Brandt).

   - Update the intel_pstate_tracer utility (Doug Smythies)"

* tag 'pm-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (128 commits)
  tools/power turbostat: update version number
  tools/power turbostat: Add Node in output
  tools/power turbostat: add node information into turbostat calculations
  tools/power turbostat: remove num_ from cpu_topology struct
  tools/power turbostat: rename num_cores_per_pkg to num_cores_per_node
  tools/power turbostat: track thread ID in cpu_topology
  tools/power turbostat: Calculate additional node information for a package
  tools/power turbostat: Fix node and siblings lookup data
  tools/power turbostat: set max_num_cpus equal to the cpumask length
  tools/power turbostat: if --num_iterations, print for specific number of iterations
  tools/power turbostat: Add Cannon Lake support
  tools/power turbostat: delete duplicate #defines
  x86: msr-index.h: Correct SNB_C1/C3_AUTO_UNDEMOTE defines
  tools/power turbostat: Correct SNB_C1/C3_AUTO_UNDEMOTE defines
  tools/power turbostat: add POLL and POLL% column
  tools/power turbostat: Fix --hide Pk%pc10
  tools/power turbostat: Build-in "Low Power Idle" counters support
  tools/power turbostat: Don't make man pages executable
  tools/power turbostat: remove blank lines
  tools/power turbostat: a small C-states dump readability immprovement
  ...
2018-06-05 09:38:39 -07:00
Tony Lindgren
7e48e23a1f
spi: Add missing pm_runtime_put_noidle() after failed get
If pm_runtime_get_sync() fails we should call pm_runtime_put_noidle().
This is probably not a critical fix as we should only hit this when
things are broken elsewhere.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-05-21 16:44:25 +01:00
Ulf Hansson
71f277a7bf spi: Respect all error codes from dev_pm_domain_attach()
The limitation of being able to check only for -EPROBE_DEFER from
dev_pm_domain_attach() has been removed. Hence let's respect all error
codes and bail out accordingly.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14 22:58:46 +02:00
Boris Brezillon
c1f5ba70de
spi: Get rid of the spi_flash_read() API
This API has been replaced by the spi_mem_xx() one, its only user
(spi-nor) has been converted to spi_mem_xx() and all SPI controller
drivers that were implementing the ->spi_flash_xxx() hooks are also
implementing the spi_mem ones. So we can safely get rid of this API.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Tested-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-05-11 11:34:41 +09:00
Boris Brezillon
b5932f5c68
spi: Make support for regular transfers optional when ->mem_ops != NULL
Some SPI/QuadSPI controllers only expose a high-level SPI memory
interface, thus preventing any regular SPI transfers from being done.

In that case, SPI controller drivers can leave all ->transfer_xxx()
hooks empty and only implement the spi_mem_ops interface.

Adjust the core to allow such situations:
- extend spi_controller_check_ops() to accept situations where all
  ->transfer_xxx() pointers are NULL only if ->mem_ops != NULL
- make sure we do not initialize the SPI message queue if
  ctlr->transfer_one and ctlr->transfer_one_message are missing
- return -ENOTSUPP if someone tries to do a regular SPI transfer on
  a controller that does not support it

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Tested-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-05-11 11:33:15 +09:00
Boris Brezillon
bdf3a3b59a
spi: Check presence the of ->transfer[_xxx]() before registering a controller
Right now, no checks are done on the presence of a ->transfer[_xxx]()
method, which can lead to a NULL pointer dereference when someone
starts sending something on the bus.

Do the check at registration time and refuse to add the controller if
all ->transfer[_xxx]() pointers are NULL.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-04-26 13:53:29 +01:00
Boris Brezillon
988f259b46
spi: Add an helper to flush the message queue
This is needed by the spi-mem logic to force all messages that have been
queued before a memory operation to be sent before we start the memory
operation. We do that in order to guarantee that spi-mem operations do
not preempt regular SPI transfers.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-04-23 15:48:18 +01:00
Boris Brezillon
46336966bf
spi: Expose spi_{map,unmap}_buf() for internal use
spi_{map,unmap}_buf() are needed by the spi-mem logic that is about to
be introduced to prepare data buffer for DMA operations.

Remove the static specifier on these functions and add their prototypes
to drivers/spi/internals.h. We do not export the symbols here because
both SPI_MEM and SPI can't be enabled as modules and we'd like to
prevent controller/device drivers from using these functions.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-04-23 15:48:06 +01:00
Mark Brown
3ce2dcf702
Merge remote-tracking branches 'spi/fix/atmel', 'spi/fix/pxa2xx' and 'spi/fix/unregiser' into spi-linus 2018-04-02 15:56:24 +01:00
Jarkko Nikula
613bd1ea38
spi: Fix unregistration of controller with fixed SPI bus number
Commit 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
ceased to unregister SPI buses with fixed bus numbers. Moreover this is
visible only if CONFIG_SPI_DEBUG=y is set or when trying to re-register
the same SPI controller.

rmmod spi_pxa2xx_platform (with CONFIG_SPI_DEBUG=y):
[   26.788362] spi_master spi1: attempting to delete unregistered controller [spi1]

modprobe spi_pxa2xx_platform:
[   37.883137] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:19.0/pxa2xx-spi.12/spi_master/spi1'
[   37.894984] CPU: 1 PID: 1467 Comm: modprobe Not tainted 4.16.0-rc4+ #21
[   37.902384] Call Trace:
...
[   38.122680] kobject_add_internal failed for spi1 with -EEXIST, don't try to register things with the same name in the same directory.
[   38.136154] WARNING: CPU: 1 PID: 1467 at lib/kobject.c:238 kobject_add_internal+0x2a5/0x2f0
...
[   38.513817] pxa2xx-spi pxa2xx-spi.12: problem registering spi master
[   38.521036] pxa2xx-spi: probe of pxa2xx-spi.12 failed with error -17

Fix this by not returning immediately from spi_unregister_controller() if
idr_find() doesn't find controller with given ID/bus number. It finds
only those controllers that were registered with dynamic SPI bus
numbers. Only conditional cleanup between dynamic and fixed bus numbers
is to remove allocated IDR.

Fixes: 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
Cc: stable@vger.kernel.org
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-03-20 17:00:19 +08:00
Maxime Chevallier
ce99319a18
spi: Fix scatterlist elements size in spi_map_buf
When SPI transfers can be offloaded using DMA, the SPI core need to
build a scatterlist to make sure that the buffer to be transferred is
dma-able.

This patch fixes the scatterlist entry size computation in the case
where the maximum acceptable scatterlist entry supported by the DMA
controller is less than PAGE_SIZE, when the buffer is vmalloced.

For each entry, the actual size is given by the minimum between the
desc_len (which is the max buffer size supported by the DMA controller)
and the remaining buffer length until we cross a page boundary.

Fixes: 65598c13fd ("spi: Fix per-page mapping of unaligned vmalloc-ed buffer")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
2018-03-02 17:31:39 +00:00
Mark Brown
b5f9208dea
Merge remote-tracking branch 'spi/topic/core' into spi-next 2017-11-10 21:33:43 +00:00
Lucas Stach
42bdd7061a
spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers
On systems where some controllers get a dynamic ID assigned and some have
a fixed number from DT, the current implemention might run into an IDR
collision if the dynamic controllers gets probed first and get an IDR number,
which is later requested by the controller with the fixed numbering. When
this happens the fixed controller will fail to register with the SPI core.

Fix this by skipping all known alias numbers when assigning the dynamic IDs.

Fixes: 9b61e30221 (spi: Pick spi bus number from Linux idr or spi alias)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-11-03 12:08:18 +01:00
Johan Hovold
68b892f1fd
spi: document odd controller reference handling
Document the fact that a reference to the controller is dropped as part
of deregistration.

This is an odd pattern as the reference is typically taken in
__spi_alloc_controller() rather than spi_register_controller(). Most
controller drivers gets it right these days and notably the
device-managed interface relies on this behaviour.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-10-31 11:09:43 +00:00
Johan Hovold
67f7b2781f
spi: fix use-after-free at controller deregistration
The controller is typically freed as part of device_unregister() so
store the bus id before deregistration to avoid use-after-free when the
id is later released.

Fixes: 9b61e30221 ("spi: Pick spi bus number from Linux idr or spi alias")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable <stable@vger.kernel.org>
2017-10-31 11:09:23 +00:00
Linus Torvalds
53ac64aac9 ACPI updates for v4.14-rc1
- Update the ACPICA code in the kernel to upstream revision 20170728
    including:
    * Alias operator handling update (Bob Moore).
    * Deferred resolution of reference package elements (Bob Moore).
    * Support for the _DMA method in walk resources (Bob Moore).
    * Tables handling update and support for deferred table
      verification (Lv Zheng).
    * Update of SMMU models for IORT (Robin Murphy).
    * Compiler and disassembler updates (Alex James, Erik Schmauss,
      Ganapatrao Kulkarni, James Morse).
    * Tools updates (Erik Schmauss, Lv Zheng).
    * Assorted minor fixes and cleanups (Bob Moore, Kees Cook,
      Lv Zheng, Shao Ming).
 
  - Rework the initialization of non-wakeup GPEs with method handlers
    in order to address a boot crash on some systems with Thunderbolt
    devices connected at boot time where we miss an early hotplug
    event due to a delay in GPE enabling (Rafael Wysocki).
 
  - Rework the handling of PCI bridges when setting up ACPI-based
    device wakeup in order to avoid disabling wakeup for bridges
    prematurely (Rafael Wysocki).
 
  - Consolidate Apple DMI checks throughout the tree, add support for
    Apple device properties to the device properties framework and
    use these properties for the handling of I2C and SPI devices on
    Apple systems (Lukas Wunner).
 
  - Add support for _DMA to the ACPI-based device properties lookup
    code and make it possible to use the information from there to
    configure DMA regions on ARM64 systems (Lorenzo Pieralisi).
 
  - Fix several issues in the APEI code, add support for exporting
    the BERT error region over sysfs and update APEI MAINTAINERS
    entry with reviewers information (Borislav Petkov, Dongjiu Geng,
    Loc Ho, Punit Agrawal, Tony Luck, Yazen Ghannam).
 
  - Fix a potential initialization ordering issue in the ACPI EC
    driver and clean it up somewhat (Lv Zheng).
 
  - Update the ACPI SPCR driver to extend the existing XGENE 8250
    workaround in it to a new platform (m400) and to work around
    an Xgene UART clock issue (Graeme Gregory).
 
  - Add a new utility function to the ACPI core to support using
    ACPI OEM ID / OEM Table ID / Revision for system identification
    in blacklisting or similar and switch over the existing code
    already using this information to this new interface (Toshi Kani).
 
  - Fix an xpower PMIC issue related to GPADC reads that always return
    0 without extra pin manipulations (Hans de Goede).
 
  - Add statements to print debug messages in a couple of places in
    the ACPI core for easier diagnostics (Rafael Wysocki).
 
  - Clean up the ACPI processor driver slightly (Colin Ian King,
    Hanjun Guo).
 
  - Clean up the ACPI x86 boot code somewhat (Andy Shevchenko).
 
  - Add a quirk for Dell OptiPlex 9020M to the ACPI backlight
    driver (Alex Hung).
 
  - Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur
    Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal,
    Ronald Tschalär, Sumeet Pawnikar).
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Merge tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These include a usual ACPICA code update (this time to upstream
  revision 20170728), a fix for a boot crash on some systems with
  Thunderbolt devices connected at boot time, a rework of the handling
  of PCI bridges when setting up device wakeup, new support for Apple
  device properties, support for DMA configurations reported via ACPI on
  ARM64, APEI-related updates, ACPI EC driver updates and assorted minor
  modifications in several places.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20170728
     including:
      * Alias operator handling update (Bob Moore).
      * Deferred resolution of reference package elements (Bob Moore).
      * Support for the _DMA method in walk resources (Bob Moore).
      * Tables handling update and support for deferred table
        verification (Lv Zheng).
      * Update of SMMU models for IORT (Robin Murphy).
      * Compiler and disassembler updates (Alex James, Erik Schmauss,
        Ganapatrao Kulkarni, James Morse).
      * Tools updates (Erik Schmauss, Lv Zheng).
      * Assorted minor fixes and cleanups (Bob Moore, Kees Cook, Lv
        Zheng, Shao Ming).

   - Rework the initialization of non-wakeup GPEs with method handlers
     in order to address a boot crash on some systems with Thunderbolt
     devices connected at boot time where we miss an early hotplug event
     due to a delay in GPE enabling (Rafael Wysocki).

   - Rework the handling of PCI bridges when setting up ACPI-based
     device wakeup in order to avoid disabling wakeup for bridges
     prematurely (Rafael Wysocki).

   - Consolidate Apple DMI checks throughout the tree, add support for
     Apple device properties to the device properties framework and use
     these properties for the handling of I2C and SPI devices on Apple
     systems (Lukas Wunner).

   - Add support for _DMA to the ACPI-based device properties lookup
     code and make it possible to use the information from there to
     configure DMA regions on ARM64 systems (Lorenzo Pieralisi).

   - Fix several issues in the APEI code, add support for exporting the
     BERT error region over sysfs and update APEI MAINTAINERS entry with
     reviewers information (Borislav Petkov, Dongjiu Geng, Loc Ho, Punit
     Agrawal, Tony Luck, Yazen Ghannam).

   - Fix a potential initialization ordering issue in the ACPI EC driver
     and clean it up somewhat (Lv Zheng).

   - Update the ACPI SPCR driver to extend the existing XGENE 8250
     workaround in it to a new platform (m400) and to work around an
     Xgene UART clock issue (Graeme Gregory).

   - Add a new utility function to the ACPI core to support using ACPI
     OEM ID / OEM Table ID / Revision for system identification in
     blacklisting or similar and switch over the existing code already
     using this information to this new interface (Toshi Kani).

   - Fix an xpower PMIC issue related to GPADC reads that always return
     0 without extra pin manipulations (Hans de Goede).

   - Add statements to print debug messages in a couple of places in the
     ACPI core for easier diagnostics (Rafael Wysocki).

   - Clean up the ACPI processor driver slightly (Colin Ian King, Hanjun
     Guo).

   - Clean up the ACPI x86 boot code somewhat (Andy Shevchenko).

   - Add a quirk for Dell OptiPlex 9020M to the ACPI backlight driver
     (Alex Hung).

   - Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur
     Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal,
     Ronald Tschalär, Sumeet Pawnikar)"

* tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits)
  ACPI / APEI: Suppress message if HEST not present
  intel_pstate: convert to use acpi_match_platform_list()
  ACPI / blacklist: add acpi_match_platform_list()
  ACPI, APEI, EINJ: Subtract any matching Register Region from Trigger resources
  ACPI: make device_attribute const
  ACPI / sysfs: Extend ACPI sysfs to provide access to boot error region
  ACPI: APEI: fix the wrong iteration of generic error status block
  ACPI / processor: make function acpi_processor_check_duplicates() static
  ACPI / EC: Clean up EC GPE mask flag
  ACPI: EC: Fix possible issues related to EC initialization order
  ACPI / PM: Add debug statements to acpi_pm_notify_handler()
  ACPI: Add debug statements to acpi_global_event_handler()
  ACPI / scan: Enable GPEs before scanning the namespace
  ACPICA: Make it possible to enable runtime GPEs earlier
  ACPICA: Dispatch active GPEs at init time
  ACPI: SPCR: work around clock issue on xgene UART
  ACPI: SPCR: extend XGENE 8250 workaround to m400
  ACPI / LPSS: Don't abort ACPI scan on missing mem resource
  mailbox: pcc: Drop uninformative output during boot
  ACPI/IORT: Add IORT named component memory address limits
  ...
2017-09-05 12:45:03 -07:00
Mark Brown
a3a424602a Merge remote-tracking branches 'spi/topic/cadence', 'spi/topic/dt', 'spi/topic/ep93xx' and 'spi/topic/falcon' into spi-next 2017-09-04 15:51:18 +01:00
Suniel Mahesh
9a9a047a39 spi: Kernel coding style fixes
Earlier commit:
"spi: Pick spi bus number from Linux idr or spi alias"
(SHA1:9b61e302210eba55768962f2f11e96bb508c2408)
has introduced some checkpatch issues. As pointed by
Lukas Wunner this patch does the following:
- remove whitespaces
- fix warnings, suspect code indent for conditional statements
- fix errors, code indent should use tabs
- remove spaces at the start of the line

Signed-off-by: Suniel Mahesh <sunil.m@techveda.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-17 17:56:11 +01:00
Suniel Mahesh
9b61e30221 spi: Pick spi bus number from Linux idr or spi alias
Modify existing code, for automatically picking the spi bus number based
on Linux idr scheme as mentioned in FIXME.
This patch does the following:
(a) Remove the now unnecessary code which was allocating bus numbers using
    ATOMIC_INIT and atomic_dec_return macros.
(b) If we have an alias, pick the bus number from alias ID
(c) Convert to linux idr interface

Signed-off-by: Suniel Mahesh <sunil.m@techveda.org>
Signed-off-by: Karthik Tummala <karthik@techveda.org>
Tested-by: Karthik Tummala <karthik@techveda.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-16 16:38:03 +01:00
Sergei Shtylyov
e0bcb680b1 spi: use of_property_read_bool()
Use a bit more compact of_property_read_bool() calls instead of the
of_find_property() calls -- symmetrically with the of_property_read_u32()
calls already done in of_spi_parse_dt().

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-07 12:49:00 +01:00
Lukas Wunner
8a2e487e6f spi: Use Apple device properties in absence of ACPI resources
MacBooks and MacBook Pros introduced since 2015 return empty _CRS data
for SPI slaves, causing device initialization to fail.  Most of the
information that would normally be conveyed via _CRS is available
through ACPI device properties instead, so take advantage of them.

The meaning and appropriate usage of the device properties was reverse
engineered by Ronald Tschalär and carried over from these commits
authored by him:

https://github.com/cb22/macbook12-spi-driver/commit/9a416d699ef4
https://github.com/cb22/macbook12-spi-driver/commit/0c34936ed9a1

According to Ronald, the device properties have the following meaning:

spiSclkPeriod   /* period in ns */
spiWordSize     /* in number of bits */
spiBitOrder     /* 1 = MSB_FIRST, 0 = LSB_FIRST */
spiSPO          /* clock polarity: 0 = low, 1 = high */
spiSPH          /* clock phase: 0 = first, 1 = second */
spiCSDelay      /* delay between cs and receive on reads in 10 us */
resetA2RUsec    /* active-to-receive delay? */
resetRecUsec    /* receive delay? */

Reported-by: Leif Liddy <leif.liddy@gmail.com>
Tested-by: Ronald Tschalär <ronald@innovation.ch>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-03 23:26:23 +02:00
Andy Shevchenko
2856670f23 spi: core: Propagate error code of add_uevent_var()
add_uevent_var() can fail, let caller know about this.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-26 15:30:35 +01:00
Rob Herring
25c56c88a4 spi: Convert to using %pOF instead of full_name
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-19 11:56:23 +01:00
Geert Uytterhoeven
8caab75fd2 spi: Generalize SPI "master" to "controller"
Now struct spi_master is used for both SPI master and slave controllers,
it makes sense to rename it to struct spi_controller, and replace
"master" by "controller" where appropriate.

For now this conversion is done for SPI core infrastructure only.
Wrappers are provided for backwards compatibility, until all SPI drivers
have been converted.

Noteworthy details:
  - SPI_MASTER_GPIO_SS is retained, as it only makes sense for SPI
    master controllers,
  - spi_busnum_to_master() is retained, as it looks up masters only,
  - A new field spi_device.controller is added, but spi_device.master is
    retained for compatibility (both are always initialized by
    spi_alloc_device()),
  - spi_flash_read() is used by SPI masters only.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-13 18:51:11 +01:00
Mark Brown
c94085f587 Merge branches 'topic/core', 'topic/slave' and 'fix/doc' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-master 2017-06-13 18:51:05 +01:00
Geert Uytterhoeven
6c364062bf spi: core: Add support for registering SPI slave controllers
Add support for registering SPI slave controllers using the existing SPI
master framework:
  - SPI slave controllers must use spi_alloc_slave() instead of
    spi_alloc_master(), and should provide an additional callback
    "slave_abort" to abort an ongoing SPI transfer request,
  - SPI slave controllers are added to a new "spi_slave" device class,
  - SPI slave handlers can be bound to the SPI slave device represented
    by an SPI slave controller using a DT child node named "slave",
  - Alternatively, (un)binding an SPI slave handler to the SPI slave
    device represented by an SPI slave controller can be done by
    (un)registering the slave device through a sysfs virtual file named
    "slave".

From the point of view of an SPI slave protocol handler, an SPI slave
controller looks almost like an ordinary SPI master controller. The only
exception is that a transfer request will block on the remote SPI
master, and may be cancelled using spi_slave_abort().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-26 13:11:00 +01:00