31 Commits

Author SHA1 Message Date
David Lechner
1fc8dc5721
spi: axi-spi-engine: remove spi_engine_get_clk_div()
Now that host->max_speed_hz and xfer->effective_speed_hz are properly
set, we can use them instead of having to do more complex calculations
to get the clock divider for each transfer.

This removes the spi_engine_get_clk_div() function and replaces it with
just dividing the two clock rates. Since the hardware register value is
the divider minus one, we need to subtract one. Subtracting one was
previously done in the spi_engine_get_clk_div() function.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-3-063672323fce@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-12-06 14:19:31 +00:00
David Lechner
9d023ecc31
spi: axi-spi-engine: populate xfer->effective_speed_hz
This adds a new spi_engine_precompile_message() function to the ADI AXI
SPI Engine driver to populate the xfer->effective_speed_hz field since
the SPI core doesn't/can't do this for us.

This driver is already using spi_delay_to_ns() which depends on
effective_speed_hz to get an accurate value in some cases.
Having an effective_speed_hz value can also be used in future changes
to simplify other code.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-2-063672323fce@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-12-06 14:19:30 +00:00
David Lechner
2e0d75f8dd
spi: axi-spi-engine: return void from spi_engine_compile_message()
In the AXI SPI Engine driver, the spi_engine_compile_message() function
does not return any error and none of the callers check the return
value. So we can change the return type to void and drop the return 0.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-1-063672323fce@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-12-06 14:19:29 +00:00
David Lechner
d861b417e1
spi: axi-spi-engine: add support for any word size
The AXI SPI Engine IP supports any word size from 1 to 32 bits. This
adds support for this by setting the bits_per_word_mask and emitting
the appropriate instruction to the SPI Engine each time a transfer
requires a new word size.

The functions that transfer tx/rx buffers from/to the SPI Engine
registers (spi_engine_write_{tx,rx}_fifo()) as well as the function that
creates the transfer instruction (spi_engine_gen_xfer()) also have to be
modified to take into account the word size since xfer->len is the
size of the buffers in bytes rather than words.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-14-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:15 +00:00
David Lechner
145bb2aedb
spi: axi-spi-engine: add support for cs_off
This adds support for the spi_transfer::cs_off flag to the AXI SPI
Engine driver.

The logic is copied from the generic spi_transfer_one_message() in
spi.c.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-13-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:14 +00:00
David Lechner
4e99144547
spi: axi-spi-engine: remove struct spi_engine::msg
In the AXI SPI Engine driver, the struct spi_engine::msg member was used
to keep track of the current message being processed. The SPI core is
already keeping track of this, so we don't need to duplicate the effort.

In most cases, we already have a pointer to the current message, so we
can pass it directly to the functions that need it. In the one case
where we don't have a pointer to the current message, we can get it
from struct spi_controller::cur_msg.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-12-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:13 +00:00
David Lechner
4a074ddeb9
spi: axi-spi-engine: remove completed_id from driver state
In the AXI SPI Engine driver, the completed_id field in the driver
state is only used in one function and the value does not need to
persist between function calls. Therefore, it can be removed from the
driver state and made a local variable in the function where it is used.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-11-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:12 +00:00
David Lechner
0c74de5c68
spi: axi-spi-engine: use message_prepare/unprepare
This modifies the AXI SPI Engine driver to make use of the
message_prepare and message_unprepare callbacks. This separates
the concerns of allocating and freeing the message state from the
transfer_one_message callback.

The main benfit of this is so that future callers of
spi_finalize_current_message() will not have to do manual cleanup
of the state.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-10-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:12 +00:00
David Lechner
7f970ecb77
spi: axi-spi-engine: move msg state to new struct
This moves the message state in the AXI SPI Engine driver to a new
struct spi_engine_msg_state.

Previously, the driver state contained various pointers that pointed
to memory owned by a struct spi_message. However, it did not set any of
these pointers to NULL when a message was completed. This could lead to
use after free bugs.

Example of how this could happen:
1. SPI core calls into spi_engine_transfer_one_message() with msg1.
2. Assume something was misconfigured and spi_engine_tx_next() is not
   called enough times in interrupt callbacks for msg1 such that
   spi_engine->tx_xfer is never set to NULL before the msg1 completes.
3. SYNC interrupt is received and spi_finalize_current_message() is
   called for msg1. spi_engine->msg is set to NULL but no other
   message-specific state is reset.
4. Caller that sent msg1 is notified of the completion and frees msg1
   and the associated xfers and tx/rx buffers.
4. SPI core calls into spi_engine_transfer_one_message() with msg2.
5. When spi_engine_tx_next() is called for msg2, spi_engine->tx_xfer is
   still be pointing to an xfer from msg1, which was already freed.
   spi_engine_xfer_next() tries to access xfer->transfer_list of one
   of the freed xfers and we get a segfault or undefined behavior.

To avoid issues like this, instead of putting per-message state in the
driver state struct, we can make use of the struct spi_message::state
field to store a pointer to a new struct spi_engine_msg_state. This way,
all of the state that belongs to specific message stays with that
message and we don't have to remember to manually reset all aspects of
the message state when a message is completed. Rather, a new state is
allocated for each message.

Most of the changes are just renames where the state is accessed. One
place where this wasn't straightforward was the sync_id member. This
has been changed to use ida_alloc_range() since we needed to separate
the per-message sync_id from the per-controller next available sync_id.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-9-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:11 +00:00
David Lechner
e6d5eb85e8
spi: axi-spi-engine: check for valid clock rate
This adds a check for a valid SCLK rate in the axi-spi-engine driver
during probe. A valid rate is required to get accurate timing for delays
and by not allowing 0 we can avoid divide by zero errors later without
additional checks.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-8-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:10 +00:00
David Lechner
e16e71e3f3
spi: axi-spi-engine: use devm_spi_register_controller()
This replaces spi_register_controller() with
devm_spi_register_controller() in the AXI SPI Engine driver. This
saves us from having to call spi_unregister_controller() in the
remove function.

The remove function is also removed since it is no longer needed.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-7-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:09 +00:00
David Lechner
076f32d5db
spi: axi-spi-engine: use devm_request_irq()
This replaces request_irq() with devm_request_irq() in the AXI SPI
Engine driver. This simplifies the error path and removes the need to
call free_irq() in the remove function.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-6-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:08 +00:00
David Lechner
e094de13ae
spi: axi-spi-engine: use devm action to reset hw on remove
This moves the reset of the hardware to a devm action in the AXI SPI
Engine driver. This will allow us to use devm on later calls in the
probe function while preserving the order during cleanup.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-5-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:07 +00:00
David Lechner
e12cd96e8e
spi: axi-spi-engine: use devm_spi_alloc_host()
This modifies the AXI SPI Engine driver to use devm_spi_alloc_host()
instead of spi_alloc_host() to simplify the code a bit.

In addition to simplifying the error paths in the probe function, we
can also remove spi_controller_get/put() calls in the remove function
since devm_spi_alloc_host() sets a flag to no longer decrement the
controller reference count in the spi_unregister_controller() function.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-4-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:06 +00:00
David Lechner
9e4ce5220e
spi: axi-spi-engine: simplify driver data allocation
This simplifies the private data allocation in the AXI SPI Engine driver
by making use of the feature built into the spi_alloc_host() function
instead of doing it manually.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-3-cc59db999b87@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-20 13:29:05 +00:00
Li Zetao
a08199b309
spi: spi-axi-spi-engine: Use helper function devm_clk_get_enabled()
Since commit 7ef9651e9792 ("clk: Provide new devm_clk helpers for prepared
and enabled clocks"), devm_clk_get() and clk_prepare_enable() can now be
replaced by devm_clk_get_enabled() when driver enables (and possibly
prepares) the clocks for the whole lifetime of the device. Moreover, it is
no longer necessary to unprepare and disable the clocks explicitly.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/r/20230823133938.1359106-6-lizetao1@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-09-11 01:31:56 +01:00
Mark Brown
f9a798867b
spi: switch to use modern name
Merge series from Yang Yingliang <yangyingliang@huawei.com>:

After introducing devm_spi_alloc_host/spi_alloc_host(), the legacy
named function devm_spi_alloc_master/spi_alloc_master() can be replaced.
And also change other legacy name master/slave to modern name host/target
or controller.
2023-08-07 21:59:25 +01:00
Ruan Jinjie
8102d64c04
spi: Do not check for 0 return after calling platform_get_irq()
It is not possible for platform_get_irq() to return 0. Use the
return value from platform_get_irq().

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> #
Link: https://lore.kernel.org/r/20230802093238.975906-1-ruanjinjie@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-08-07 14:38:40 +01:00
Yang Yingliang
9d5920b37a
spi: spi-axi-spi-engine: switch to use modern name
Change legacy name master to modern name host or controller.

No functional changed.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20230728093221.3312026-4-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-08-07 14:38:19 +01:00
Amit Kumar Mahapatra via Alsa-devel
9e264f3f85
spi: Replace all spi->chip_select and spi->cs_gpiod references with function call
Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod
members of struct spi_device to be an array. But changing the type of these
members to array would break the spi driver functionality. To make the
transition smoother introduced four new APIs to get/set the
spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and
spi->cs_gpiod references with get or set API calls.
While adding multi-cs support in further patches the chip_select & cs_gpiod
members of the spi_device structure would be converted to arrays & the
"idx" parameter of the APIs would be used as array index i.e.,
spi->chip_select[idx] & spi->cs_gpiod[idx] respectively.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver
Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi
Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part
Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-11 12:34:01 +00:00
Uwe Kleine-König
fc87abbef2
spi: axi-spi-engine: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230303172041.2103336-9-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-06 12:29:27 +00:00
Alexandru Ardelean
93c9414489
spi: spi-axi-spi-engine: remove usage of delay_usecs
The 'delay_usecs' field was handled for backwards compatibility in case
there were some users that still configured SPI delay transfers with
this field.

They should all be removed by now.

Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210308145502.1075689-2-aardelean@deviqon.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-03-12 14:30:42 +00:00
Rafał Hibner
d103729a62
spi: spi-axi-spi-engine: Access register after clock initialization
Move register access after clock initialization.
Clock "s_axi_aclk" is needed for register access. Without the clock running
AXI bus hangs and causes kernel freeze.

Signed-off-by: Rafał Hibner <rafal.hibner@secom.com.pl>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Cc: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200409155621.12174-1-rafal.hibner@secom.com.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-04-09 18:46:53 +01:00
Alexandru Ardelean
acc7720de3
spi: spi-axi: extend support for the delay field
The AXI SPI engine driver uses the `delay_usecs` field from `spi_transfer`
to configure delays, which the controller will execute.
This change extends the logic to also include the `delay` value, in case it
is used (instead if `delay_usecs`).

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-20-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15 11:47:26 +01:00
YueHaibing
7d6a5e2b17
spi: spi-axi: use devm_platform_ioremap_resource() to simplify code
Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190904135918.25352-5-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-04 17:15:49 +01:00
Thomas Gleixner
fda8d26e61 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 177
Based on 1 normalized pattern(s):

  licensed under the gpl 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 135 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: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.071193225@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:19 -07:00
Johan Hovold
4d5e0689dc
spi: spi-axi: fix potential use-after-free after deregistration
Take an extra reference to the controller before deregistering it to
prevent use-after-free in the interrupt handler in case an interrupt
fires before the line is disabled.

Fixes: b1353d1c1d45 ("spi: Add Analog Devices AXI SPI Engine controller support")
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-10-31 11:15:10 +00:00
Christophe JAILLET
9620ca9011 spi: spi-axi: Free resources on error path
We should go to 'err_put_master' here instead of returning directly.
Otherwise a call to 'spi_master_put' is missing.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-09 11:20:46 +00:00
Javier Martinez Canillas
01affe239c spi: spi-axi: Fix module autoload
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/spi/spi-axi-spi-engine.ko | grep alias
$

After this patch:

$ modinfo drivers/spi/spi-axi-spi-engine.ko | grep alias
alias:          of:N*T*Cadi,axi-spi-engine-1.00.aC*
alias:          of:N*T*Cadi,axi-spi-engine-1.00.a

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-23 16:42:08 +00:00
Axel Lin
71c5e53b42 spi: Drop duplicate code to set master->dev.parent
It's done by spi_alloc_master().

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-26 11:56:09 +01:00
Lars-Peter Clausen
b1353d1c1d spi: Add Analog Devices AXI SPI Engine controller support
This patch adds support for the AXI SPI Engine controller which is a FPGA
soft-peripheral which is used in some of Analog Devices' reference designs.

The AXI SPI Engine controller is part of the SPI Engine framework[1] and
allows memory mapped access to the SPI Engine control bus. This allows it
to be used as a general purpose software driven SPI controller. The SPI
Engine in addition offers some optional advanced acceleration and
offloading capabilities, which are not part of this patch though and will
be introduced separately.

At the core of the SPI Engine framework is a small sort of co-processor
that accepts a command stream and turns the commands into low-level SPI
transactions. Communication is done through three memory mapped FIFOs in
the register map of the AXI SPI Engine peripheral. One FIFO for the command
stream and one each for transmit and receive data.

The driver translates a spi_message in a command stream and writes it to
the peripheral which executes it asynchronously. This allows it to perform
very precise timings which are required for some SPI slave devices to
achieve maximum performance (e.g. analog-to-digital and digital-to-analog
converters). The execution flow is synchronized to the host system by a
special synchronize instruction which generates a interrupt.

[1] https://wiki.analog.com/resources/fpga/peripherals/spi_engine

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-05 18:12:57 +00:00