pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523133859.5625-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200320232515.GA24800@embeddedor.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Why it does not work at the moment:
- num_chipselect sets the number of cs-gpios that are in the DT.
This comes from drivers/spi/spi.c
- num_chipselect gets set with devm_spi_register_controller, that is
called in drivers/spi/spi.c
- devm_spi_register_controller got called after num_chipselect has
been used.
How this commit fixes the issue:
- devm_spi_register_controller gets called before num_chipselect is
being used.
Fixes: c7a4025995 ("spi: lpspi: use the core way to implement cs-gpio function")
Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Link: https://lore.kernel.org/r/20191204141312.1411251-1-philippe.schenker@toradex.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixes coccicheck warning:
drivers/spi/spi-fsl-lpspi.c:472:2-19: WARNING: Assignment of 0/1 to bool variable
drivers/spi/spi-fsl-lpspi.c:474:2-19: WARNING: Assignment of 0/1 to bool variable
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Link: https://lore.kernel.org/r/1577159526-33689-2-git-send-email-zhengbin13@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
dma_request_slave_channel_reason() is:
#define dma_request_slave_channel_reason(dev, name) \
dma_request_chan(dev, name)
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191113094256.1108-4-peter.ujfalusi@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In fsl_lpspi_probe an SPI controller is allocated either via
spi_alloc_slave or spi_alloc_master. In all but one error cases this
controller is put by going to error handling code. This commit fixes the
case when pm_runtime_get_sync fails and it should go to the error
handling path.
Fixes: 944c01a889 ("spi: lpspi: enable runtime pm for lpspi")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Link: https://lore.kernel.org/r/20190930034602.1467-1-navid.emamdoost@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Use is_slave local variable to avoid calling of_property_read_bool() twice.
Remove redudant assignment for controller->bus_num, set it once is enough.
Move setting controller->bits_per_word_mask close to the code init other
controller fields.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add #ifdef CONFIG_PM guard to fix build warning when !CONFIG_PM
drivers/spi/spi-fsl-lpspi.c:810:12: warning: ‘fsl_lpspi_runtime_suspend’ defined but not used [-Wunused-function]
static int fsl_lpspi_runtime_suspend(struct device *dev)
^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/spi/spi-fsl-lpspi.c:789:12: warning: ‘fsl_lpspi_runtime_resume’ defined but not used [-Wunused-function]
static int fsl_lpspi_runtime_resume(struct device *dev)
^~~~~~~~~~~~~~~~~~~~~~~~
Fixes: 944c01a889 ("spi: lpspi: enable runtime pm for lpspi")
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The original code already set controller as drvdata:
platform_set_drvdata(pdev, controller);
But commit 944c01a889 ("spi: lpspi: enable runtime pm for lpspi")
added dev_set_drvdata(&pdev->dev, fsl_lpspi);
so fsl_lpspi_remove() will get wrong pointer by platform_get_drvdata().
Fixes: 944c01a889 ("spi: lpspi: enable runtime pm for lpspi")
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add the missing complete operations for dma_completion to fix the
problem of blocking at the wait_for_completion_interruptible()
function when use spi_slave_abort().
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If we don't use CONT to keep SS activated or use DMA mode without
cs-gpio, SS will be inactivated between every words. The word here
means the data sent once which length can be set as 1/2/4 bytes.
In the isr function, we read the FSR_RXCOUNT just behind the
fsl_lpspi_read_rx_fifo. This causes the value of FSR_RXCOUNT cannot
reflect whether there is still data not sent timely. So do this
judgement by FSR_TXCOUNT.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fixes: 944c01a889 ("spi: lpspi: enable runtime pm for lpspi")
Signed-off-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The spi_transfer *t will be used in one transfer whatever. If t is NULL,
there has no need to try sending data, so add an error return here.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Acked-by: Fugang Duan <Fugang.duan@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add dma mode support for LPSPI. Any frame longer than half txfifosize will
be sent by dma mode.
For now, there are some limits:
1. The maximum transfer speed in master mode depends on the slave device,
at least 40MHz(tested by spi-nor on 8qm-lpddr4-arm2 base board);
2. The maximum transfer speed in slave mode is 15MHz(imx7ulp),
22MHz(8qm/qxp). In order to reach the maximum speed which is mentioned
in datasheet, the load of connect wires between master and slave
should be less than 15pF.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Acked-by: Fugang Duan <Fugang.duan@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use the default implementation of transfer_one_msg/chipselect/setup
functions in spi core to implement cs-gpio control.
Use fsl_lpspi_prepare_message to init the cs_gpio pin.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Acked-by: Fugang Duan <Fugang.duan@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add a error info when set a speed which greater than half of per-clk of
spi module.
The minimum SCK period is 2 cycles(CCR[SCKDIV]). So the maximum transfer
speed is half of spi per-clk.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Enable the runtime power management for lpspi module.
Do some adaptation work from kernel 4.9 to 4.14.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Reviewed-by: Frank Li <frank.li@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add both ipg and per clock for lpspi to support i.MX8QM/QXP boards.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Remove Reset operation in fsl_lpspi_config(). This RST may cause both CLK
and CS pins go from high to low level under cs-gpio mode.
Add fsl_lpspi_reset() function after one message transfer to clear all
flags in use.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add judgment on SR_MBF and FSR_RXCOUNT.
In PIO mode, if don't use CONT to keep cs selected in one transfer, the
transfer will go wrong. FCIE will be set after one frame transfer
finish. If use CONT, the frame refer to the whole data in one transfer.
If don't use CONT, the frame refer to one byte of whole data. This will
cause the transfer ending early.
This patch add a register reading in isr function, it might lead to a
slight decrease in the max transmission speed in PIO mode.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use SR_TDF to judge if need to send data, and SR_FCF is to judge if
transmission end and to replace the waiting after transmission end.
This waiting has no actual meaning, for module will set the FCF
flag at the real end.
The changes of interrupt flag and ISR function reduce the times of
calling ISR. The use of the FCF flag improves the stability of the
data transmission. These two points generally improve the data
transfer speed of lpspi, especially when it is set to slave mode
it can support higher transfer speed of the host.
After making these changes, there is no need to use
fsl_lpspi_txfifo_empty(), so remove it.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Configure watermark to change with the length of the sent data.
Support LPSPI sending message shorter than tx/rxfifosize.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add slave mode support to the fsl-lpspi driver, only in PIO mode.
For now, there are some limitations for slave mode transmission:
1. The stale data in RXFIFO will be dropped when the Slave does any new
transfer.
2. One transfer can be finished only after all transfer->len data been
transferred to master device
3. Slave device only accepts transfer->len data. Any data longer than
this from master device will be dropped. Any data shorter than this
from master will cause LPSPI to stuck due to mentioned limitation 2.
4. Only PIO transfer is supported in Slave Mode.
Wire connection:
GND, SCK, MISO(to MISO of slave), MOSI(to MOSI of slave), SCS
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In order to enable the slave mode and make the code more readable,
replace all related structure names and object names which is
named "master" with "controller".
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Certain devices don't work well when a transmit FIFO underrun or
receive FIFO overrun occurs. Example is the SAF400x radio chip when
running at high speed which leads to garbage being sent to/received from
the chip. In which case, it should stall waiting for further data to be
available before proceeding. This patch unset the NOSTALL bit in CFGR1
by default to prevent this issue.
Signed-off-by: Hieu Tran Dang <dangtranhieu2012@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
With gcc 4.1.2:
drivers/spi/spi-fsl-lpspi.c: In function ‘fsl_lpspi_transfer_one_msg’:
drivers/spi/spi-fsl-lpspi.c:369: warning: ‘ret’ may be used uninitialized in this function
If the message contains no transfers, the function will set the
message's status to an uninitialized value, and will return that
uninitialized value.
While __spi_validate() should have been called in all paths leading to
this, and thus have rejected such messages, we better pre-initialize ret
to be safe for future modifications (spi_transfer_one_message() also
does this).
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In case that error occurs during waiting for txfifo empty, it is
not necessary to read rx fifo. It's better to return directly.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
At the beginning of lpspi driver, it is claimed that the dirver
is under the terms of the GNU General Public License, either
version 2 of the License. While at the end I only declared GPL V2.
This patch make the license consistent.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The lpspi tx/rx fifo size is a read only parameter resides
lpspi Parameter Register. It's better to read lpspi tx/rx
fifo size in probe().
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It's a potential problem to use wait_for_completion() because the
completion condition may never come. Thus, it's better to repalce
wait_for_completion() with wait_for_completion_timeout().
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It's more rational that just do the schedule when necessary
other than do it every time. Thus, it's better to replace
schedule() with cond_resched() in fsl_lpspi_txfifo_empty(),
which contributes to saving cpu time.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is a static checker warning in fsl_lpspi_set_cmd().
I intended to write "temp |= (fsl_lpspi->config.mode & 0x3) << 30",
but used "temp |= (fsl_lpspi->config.mode & 0x11) << 30" by mistake.
This patch fixes this potential shift truncation.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The old driver enable clk in fsl_lpspi_prepare_message() and
disable clk in fsl_lpspi_unprepare_message().
Rather than doing this per message it's a bit better to do it
in prepare_transfer_hardware(), that way if there's a sequence
of messages queued one after another we don't turn the clock on
and off all the time.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds lpspi driver to support new i.MX products which use
lpspi instead of ecspi.
The lpspi can continue operating in stop mode when an appropriate
clock is available. It is also designed for low CPU overhead with
DMA offloading of FIFO register accesses.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Dinghao Liu