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>
