Allow SPI peripherals attached to this controller to know what is the
maximum transfer size and message size, so they can limit their transfer
lengths properly in case they are otherwise capable of larger transfer
sizes. For the sc18is602, this is 200 bytes in both cases, since as far
as I understand, it isn't possible to tell the controller to keep the
chip select asserted after the STOP command is sent.
The controller can support SPI messages larger than 200 bytes if
cs_change is set for individual transfers such that the portions with
chip select asserted are never longer than 200 bytes. What is not
supported is just SPI messages with a continuous chip select larger than
200. I don't think it is possible to express this using the current API,
so drivers which do send SPI messages with cs_change can safely just
look at the max_transfer_size limit.
An example of user for this is sja1105_xfer() in
drivers/net/dsa/sja1105/sja1105_spi.c which sends by default 64 * 4 =
256 byte transfers.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20210520131238.2903024-3-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
For each spi_message, the sc18is602 I2C-to-SPI bridge driver checks the
length of each spi_transfer against 200 (the size of the chip's internal
buffer) minus hw->tlen (the number of bytes transferred so far).
The first byte of the transferred data is the Function ID (the SPI
slave's chip select) and as per the documentation of the chip:
https://www.nxp.com/docs/en/data-sheet/SC18IS602B.pdf
the data buffer is up to 200 bytes deep _without_ accounting for the
Function ID byte.
However, in sc18is602_txrx(), the driver keeps the Function ID as part
of the buffer, and increments hw->tlen from 0 to 1. Combined with the
check in sc18is602_check_transfer, this prevents us from issuing a
transfer that has exactly 200 bytes in size, but only 199.
Adjust the check function to reflect that the Function ID is not part of
the 200 byte deep data buffer.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20210520131238.2903024-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If the call to devm_gpiod_get_optional() fails on probe of the NXP
SC18IS602/603 SPI driver, the spi_master struct is erroneously not freed.
Fix by switching over to the new devm_spi_alloc_master() helper.
Fixes: f99008013e ("spi: sc18is602: Add reset control via gpio pin.")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v4.9+: 5e844cc37a: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v4.9+
Cc: Phil Reid <preid@electromag.com.au>
Link: https://lore.kernel.org/r/d5f715527b894b91d530fe11a86f51b3184a4e1a.1607286887.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
For many places in the spi drivers, using the new `spi_transfer_delay`
helper is straightforward.
It's just replacing:
```
if (t->delay_usecs)
udelay(t->delay_usecs);
```
with `spi_transfer_delay(t)` which handles both `delay_usecs` and the new
`delay` field.
This change replaces in all places (in the spi drivers) where this change
is simple.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-10-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.
But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
To avoid warning when using i2c gpio expander change call to the
cansleep variant. There should be no issue with sleeping in the
drivers probe function.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Mark Brown <broonie@kernel.org>
This sc18is602 has a reset pin that may need to be deasserted.
Add optional binding to specifiy the reset pin via a gpio and deassert
during probe.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver currently only supports a single device per I2C bus since it uses
the I2C bus number to set the SPI bus number. This makes it impossible to
connect more than one chip to a single I2C bus.
We don't want to use dynamic bus numbers unconditionally since this would
result in every instantiation getting a different bus number starting with
65,535 counting down unless devicetree is configured. If devicetree is
configured, however, the SPI bus number is obtained from devicetree
data. So we can use dynamic SPI bus numbers in this case.
Reported-and-Tested-by: Marco Menchise <marco.menchise@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
Set master->max_speed_hz and master->min_speed_hz then spi core will handle
checking transfer speed. So we can remove the same checking in this driver.
This patch also remove testing if hz is 0 because spi->max_speed_hz will be
default set to master->min_speed_hz if it was not set. So the transfer speed
will never set to 0.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
So it will be checked when spi device is added onto the spi bus.
spi_add_device() calls spi_setup() which then calls spi->master->setup().
No need to check it every time sc18is602_transfer_one() is called.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
The checking for spi->mode is done in the implementation of spi_setup().
Calling sc18is602_check_transfer(spi, NULL, 0) is pointless because
the code is equivent to checking if spi->max_speed_hz is 0.
Note, sc18is602_check_transfer actually allows spi->max_speed_hz is 0
if t->speed_hz is set. So return error in sc18is602_setup() when
spi->max_speed_hz is 0 does not make sense.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
Since commit 543bb25 "spi: add ability to validate xfer->bits_per_word in SPI
core", the driver can set bits_per_word_mask for the master then the SPI core
will reject transfers that attempt to use an unsupported bits_per_word value.
So we can remove the bits_per_word checking in sc18is602_check_transfer() and
let SPI core handle the checking.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
The implementation in spi_setup() already set spi->bits_per_word = 8 when
spi->bits_per_word is 0 before calling spi->master->setup.
So we don't need to do it again in setup() callback.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
Use devm_spi_register_master() to make cleanup paths simpler,
and remove unnecessary remove().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@linaro.org>
If the I2C bus master driver does not support the required functionality,
the driver returns -ENODEV. This causes a silent probe failure without error
message. Since the device has to be explicitly instantiated, and the user
should know the correct bus, this event really reflects an error condition.
Replace error return value with -EINVAL to trigger an error message showing
that the probe function failed.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This driver adds support for NXP SC18IS602/603 I2C to SPI bus bridge.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
