Commit Graph

111 Commits

Author SHA1 Message Date
Greg Ungerer
602c8f4485 spi: imx: fix use of native chip-selects with devicetree
The commonly used mechanism of specifying the hardware or native
chip-select on an SPI device in devicetree (that is "cs-gpios = <0>")
does not result in the native chip-select being configured for use.
So external SPI devices that require use of the native chip-select
will not work.

You can successfully specify native chip-selects if using a platform
setup by specifying the cs-gpio as negative offset by 32. And that
works correctly. You cannot use the same method in devicetree.

The logic in the spi-imx.c driver during probe uses core spi function
of_spi_register_master() in spi.c to parse the "cs-gpios" devicetree tag.
For valid GPIO values that will be recorded for use, all other entries in
the cs_gpios list will be set to -ENOENT. So entries like "<0>" will be
set to -ENOENT in the cs_gpios list.

When the SPI device registers are setup the code will use the GPIO
listed in the cs_gpios list for the desired chip-select. If the cs_gpio
is less then 0 then it is intended to be for a native chip-select, and
its cs_gpio value is added to 32 to get the chipselect number to use.
Problem is that with devicetree this can only ever be -ENOENT (which
is -2), and that alone results in an invalid chip-select number. But also
doesn't allow selection of the native chip-select at all.

To fix, if the cs_gpio specified for this spi device is not a
valid GPIO then use the "chip_select" (that is the native chip-select
number) for hardware setup.

Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Tested-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-29 21:09:03 +01:00
Arnd Bergmann
5904c9d3c9 spi: imx: fix little-endian build
The newly added dynamic burst code produces a harmless warning
on big-endian configurations:

drivers/spi/spi-imx.c: In function 'spi_imx_buf_rx_swap_u32':
drivers/spi/spi-imx.c:284:15: error: unused variable 'bytes_per_word' [-Werror=unused-variable]
  unsigned int bytes_per_word;
               ^~~~~~~~~~~~~~
drivers/spi/spi-imx.c: In function 'spi_imx_buf_tx_swap_u32':
drivers/spi/spi-imx.c:319:15: error: unused variable 'bytes_per_word' [-Werror=unused-variable]
  unsigned int bytes_per_word;

This adds another #ifdef around the variable declaration matching
the one on the use.

Fixes: 1673c81d94 ("spi: imx: dynamic burst length adjust for PIO mode")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-23 16:53:30 +01:00
jiada wang
1673c81d94 spi: imx: dynamic burst length adjust for PIO mode
previously burst length (BURST_LENGTH) is always set to equal
to bits_per_word, causes a 10us gap between each word in
transfer, which significantly affects performance.

This patch uses 32 bits transfer to simulate lower bits transfer,
and adjusts burst length runtimely to use biggeest burst length
as possible to reduce the gaps in transfer for PIO mode.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-17 15:27:13 +01:00
Oleksij Rempel
ab2f357223 spi: imx: add SPI_NO_CS support
To run spi-loopback-tests on HW without modifications, we need to
disable Chip Select. This should avoid surprising side effects for SPI devices
by testing patterns.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-26 13:10:01 +01:00
jiada wang
26e4bb8670 spi: imx: add selection for iMX53 and iMX6 controller
ECSPI contorller for iMX53 and iMX6 has few hardware issues
comparing to iMX51.
The change add possibility to detect which controller is used
to apply possible workaround and limitations.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-17 12:09:48 +01:00
jiada wang
fd8d4e2d1f spi: imx: introduce fifo_size and has_dmamode in spi_imx_devtype_data
Different ECSPI controller has different fifosize and DMA capability,
instead of calling functions to identify these information by check
devtype. add fifo_size and has_dmamode to spi_imx_devtype_data.
so that these information can be directly accessed.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-17 12:09:47 +01:00
Fabio Estevam
2c147776dc spi: imx: Check for allocation failure earlier
In case of spi_alloc_master() failure it is better to return the
error immediately, so move the error check right after the allocation.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-21 12:09:07 +01:00
Sascha Hauer
2e312f6cdb spi: imx: rename 'bpw' variables
'bpw' is ambiguous and only the context makes sure if bytes_per_word
or bits_per_word is meant. Use the full names instead to make reading
the code easier.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-06 19:48:23 +01:00
Sascha Hauer
65017ee2cd spi: imx: remove bytes_per_word from private driver struct
We already have bits_per_word in the private driver struct and
bytes_per_word can be calculated from it, so remove bits_per_word.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-06 19:48:23 +01:00
Sascha Hauer
d6be7d1db5 spi: imx: drop bogus unnecessary dma config
It's unnecessary to call spi_imx_dma_configure() from probe(). It will
be called later anyway again when an actual DMA transfer is prepared.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-06 19:48:23 +01:00
Sascha Hauer
d52345b6cf spi: imx: put struct spi_imx_config members into driver private struct
struct spi_imx_config used to hold data specific to the current
transfer. However, other data is in the drivers private data struct.
Let's drop struct spi_imx_config and put the variables into the
drivers private data struct aswell.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-06 19:48:23 +01:00
Sascha Hauer
494f3193bd spi: imx: Drop unnecessary check
__spi_validate makes sure that every transfer has a valid bits_per_word
and speed_hz setting. We do not need to fallback to values from the
spi_device.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-06 19:48:23 +01:00
Sascha Hauer
abb1ff195a spi: imx: Nothing to do in setupxfer when transfer is NULL
When the spi_transfer given in spi_imx_setupxfer is NULL then
we have nothing to do. Bail out early in this case so that
we do not have to test for t != NULL multiple times later.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-06 19:48:22 +01:00
Sascha Hauer
09b3ed2d59 spi: imx: Revert "spi: imx: dynamic burst length adjust for PIO mode"
This reverts commits 8d4a6cad7a and
179547e143.

Besides the problems already found with this patch it also modifies
the spi transfer tx_buf in spi_imx_u32_swap_u8() and spi_imx_u32_swap_u16().
This is hidden from the compiler with an explicit cast from const void*
to u32*, so no warning is issued.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-23 19:22:08 +01:00
Jiada Wang
179547e143 spi: imx: fix issue when tx_buf or rx_buf is NULL
In case either transfer->tx_buf or transfer->rx_buf is NULL,
manipulation of buffer in spi_imx_u32_swap_u[8|16]() will cause
NULL pointer dereference crash.

Add buffer check at very beginning of spi_imx_u32_swap_u[8|16](),
to avoid such crash.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Tested-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-19 17:57:08 +01:00
Jiada Wang
8d4a6cad7a spi: imx: dynamic burst length adjust for PIO mode
previously burst length (BURST_LENGTH) is always set to equal
to bits_per_word, causes a 10us gap between each word in
transfer, which significantly affects performance.

This patch uses 32 bits transfer to simulate lower bits transfer,
and adjusts burst length runtimely to use biggeest burst length
as possible to reduce the gaps in transfer for PIO mode.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-14 19:06:33 +09:00
Leif Middelschulte
f72efa7e69 spi-imx: Implements handling of the SPI_READY mode flag.
This patch implements consideration of the SPI_READY mode flag as
defined in spi.h. It extends the device tree bindings to support
the values defined by the reference manual for the DRCTL field.

Thus supporting edge-triggered and level-triggered bursts.

Signed-off-by: Leif Middelschulte <Leif.Middelschulte@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-04-25 16:37:53 +01:00
Jiada Wang
66459c5a50 spi: imx: adjust watermark level according to transfer length
Previously DMA watermark level is configured to fifosize/2,
DMA mode can be used only when transfer length can be divided
by 'watermark level * bpw', which makes DMA mode not pratical.

This patch adjusts watermark level to largest number (no bigger
than fifosize/2) which can divide 'tranfer length / bpw' for
each transfer.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-06 18:09:22 +00:00
Robert Baldyga
32df9ff2b8 spi: imx: set spi_bus_clk for mx21 and mx27
Introduce additional output parameter in spi_imx_clkdiv_1()
function to return result frequency and set it to spi_bus_clk.

This fixes division by zero bug, which occurred in
spi_imx_calculate_timeout() function.

Signed-off-by: Robert Baldyga <r.baldyga@hackerion.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-02 09:30:43 -06:00
Martin Kaiser
2dd33f9cec spi: imx: support DMA for imx35
Support DMA transfers on imx35 and compatible chipsets (imx31, imx25).

If DMA can be used, set the start mode control (SMC) bit to start the
SPI burst as soon as data is written into the tx fifo. Configure DMA
requests when the fifo is half empty during tx or half full during rx.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-24 18:04:23 +01:00
Wei Yongjun
446576f9ea spi: imx: fix error return code in spi_imx_probe()
Fix to return error code -EINVAL if no CS GPIOs available
instead of 0, as done elsewhere in this function.

Fixes: f13d4e189d ("spi: imx: Gracefully handle NULL master->cs_gpios")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-28 09:50:55 -07:00
Marek Vasut
f13d4e189d spi: imx: Gracefully handle NULL master->cs_gpios
It is possible that master->cs_gpios is NULL after spi_bitbang_start(),
this happens if the master has no CS GPIOs specified in DT. Check for
this case after spi_bitbang_start() to prevent NULL pointer dereference
in the subsequent for loop, which accesses the master->cs_gpios field.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Martin Kaiser <martin@kaiser.cx>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-26 09:08:46 -07:00
Martin Kaiser
15ca92156e spi: imx: support loopback mode on imx35
imx35 and compatible chipsets support loopback mode by setting a
loopback control bit in the test register. Make this setting available
for data transfers, similar to what we do for imx51.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-14 18:06:16 +01:00
Martin Kaiser
2636ba8fa3 spi: imx: set spi_bus_clk for mx1, mx31 and mx35
Modify spi_imx_clkdiv_2() to return the resulting bus clock frequency
when the selected clock divider is applied. Set spi_imx->spi_bus_clk to
this frequency.

If spi_bus_clk is unset, spi_imx_calculate_timeout() causes a
division by 0.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-14 18:06:11 +01:00
Christian Gmeiner
ff1ba3dac0 spi: imx: wait_for_completion_timeout(..) for PIO transfers
In some rare cases I see the following 'task blocked' information. It
looks like the PIO transfer has some problems and never succeeds. Make
use of wait_for_completion_timeout(..) to detect this case and
return -ETIMEDOUT.

[ 240.246067] INFO: task hexdump:1660 blocked for more than 120 seconds.
[ 240.246089] Not tainted 4.1.17 0000001
[ 240.246099] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 240.246109] hexdump D c0575548 0 1660 1 0x00000000
[ 240.246132] Backtrace:
[ 240.246166] [<c057524c>] (__schedule) from [<c0575a84>] (schedule+0x40/0xa4)
[ 240.246176] r10:00000000 r9:c07f1300 r8:c07b8408 r7:c0576518 r6:7fffffff r5:7fffffff
[ 240.246210] r4:ee972e7c
[ 240.246233] [<c0575a44>] (schedule) from [<c0578544>] (schedule_timeout+0x174/0x274)
[ 240.246254] [<c05783d0>] (schedule_timeout) from [<c0576518>] (wait_for_common+0xc0/0x164)
[ 240.246263] r10:00000000 r9:c07f1300 r8:00000002 r7:00000000 r6:7fffffff r5:ee972e78
[ 240.246294] r4:ee972e7c
[ 240.246314] [<c0576458>] (wait_for_common) from [<c05765dc>] (wait_for_completion+0x20/0x24)
[ 240.246324] r10:ee972e50 r8:00000001 r7:c3976200 r6:ee972c00 r5:ee972e50 r4:c2c87d28
[ 240.246367] [<c05765bc>] (wait_for_completion) from [<c03f6b04>] (spi_imx_transfer+0xe8/0x3cc)
[ 240.246393] [<c03f6a1c>] (spi_imx_transfer) from [<c03f50e4>] (spi_bitbang_transfer_one+0xb4/0x250)
[ 240.246403] r10:ee972e50 r8:00000001 r7:00000000 r6:c2c87da0 r5:00000000 r4:c2c87d28
[ 240.246443] [<c03f5030>] (spi_bitbang_transfer_one) from [<c03f36e8>] (__spi_pump_messages+0x36c/0x6b4)
[ 240.246452] r10:ee9e5010 r9:00000001 r8:ee9e5010 r7:00000000 r6:c2c87da0 r5:c2c87d6c
[ 240.246483] r4:ee972c00
[ 240.246503] [<c03f337c>] (__spi_pump_messages) from [<c03f3b68>] (__spi_sync+0x138/0x1e4)
[ 240.246512] r10:00000000 r9:00000000 r8:c03f25a8 r7:00000000 r6:ee972c00 r5:c3976200
[ 240.246542] r4:c2c87da0
[ 240.246562] [<c03f3a30>] (__spi_sync) from [<c03f3c50>] (spi_sync+0x1c/0x20)
[ 240.246571] r10:00040000 r9:00000000 r8:c3976200 r7:00000000 r6:ee973300 r5:c2c87da0
[ 240.246602] r4:ee973014
[ 240.246623] [<c03f3c34>] (spi_sync) from [<c03f0210>] (m25p80_read+0xf8/0x124)
[ 240.246641] [<c03f0118>] (m25p80_read) from [<c03f1528>] (spi_nor_read+0x64/0x80)
[ 240.246651] r10:00004000 r8:00004000 r7:00000000 r6:00040000 r5:00000000 r4:ee973014
[ 240.246698] [<c03f14c4>] (spi_nor_read) from [<c03cdcb4>] (mtd_read+0x98/0xcc)
[ 240.246708] r7:c2c87ea0 r6:ee973098 r5:00000000 r4:001c0000
[ 240.246740] [<c03cdc1c>] (mtd_read) from [<c03d300c>] (mtdchar_read+0xcc/0x204)
[ 240.246750] r9:ed424000 r8:00000000 r7:b495d018 r6:c2c87f78 r5:00000000 r4:00040000
[ 240.246793] [<c03d2f40>] (mtdchar_read) from [<c013b1c4>] (__vfs_read+0x3c/0xe0)
[ 240.246803] r10:00004000 r9:00000000 r8:c2c87f78 r7:b495d018 r6:c2c87f78 r5:c05c8104
[ 240.246833] r4:c32fe600
[ 240.246852] [<c013b188>] (__vfs_read) from [<c013befc>] (vfs_read+0x98/0x154)
[ 240.246861] r10:00000000 r8:00040000 r7:00004000 r6:c2c87f78 r5:b495d018 r4:c32fe600
[ 240.246899] [<c013be64>] (vfs_read) from [<c013c008>] (SyS_read+0x50/0x90)
[ 240.246908] r10:00000000 r8:00040000 r7:b495d018 r6:00004000 r5:c32fe601 r4:c32fe600
[ 240.246953] [<c013bfb8>] (SyS_read) from [<c000fa60>] (ret_fast_syscall+0x0/0x3c)
[ 240.246962] r9:c2c86000 r8:c000fc04 r7:00000003 r6:00004000 r5:00000000 r4:b495d018

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-21 19:52:15 +01:00
Alexander Shiyan
f989bc6958 spi: imx: Remove "maybe_unused" attributes
The SPI-driver no longer contains the conditions for various CPUs, so
"maybe_unused" attributes is no longer needed.
This patch removes these attributes.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-14 10:19:47 +01:00
Alexander Shiyan
c0c7a5d796 spi: imx: Remove unnecessary field "mode" from struct spi_imx_config
SPI mode can be obtained directly from spi-device, there is no
need to keep a copy.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-14 10:19:44 +01:00
Alexander Shiyan
b36581df7e spi: imx: Using existing properties for chipselects
Patch reuse existing "chip_select" and "cs_gpio(s)" fields from SPI core.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-14 10:19:41 +01:00
Sascha Hauer
cd8dd41a33 spi: imx: Fix possible NULL pointer deref
transfer could be NULL in spi_imx_can_dma() when it's called from
spi_imx_setupxfer() with a NULL transfer. Test for a NULL pointer before
dereferencing it.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-17 11:44:34 +00:00
Knut Wohlrab
793c7f9212 spi: imx: only do necessary changes to ECSPIx_CONFIGREG
If the SPI chip select (CS) for a dedicated channel is done manually by
the used higher device driver, the CS may be active while writing to
ECSPIx_CONFIGREG. To prevent unwanted clock edges when selecting
the clock mode,  only do the necessary changes to the i.MX SPI
configuration register and leave not selected channels untouched.

To prevent unwanted clock edges on first use, an empty dummy
transmission shall be done by the initialization procedure of the device
driver of this channel. This will set the clock mode to the correct state.

Signed-off-by: Knut Wohlrab <knut.wohlrab@de.bosch.com>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-17 11:44:11 +00:00
Sascha Hauer
6b6192c04b spi: imx: drop bogus tests for rx/tx bufs in DMA transfer
The driver tries to be clever by only setting up DMA channels when
the corresponding sg tables are non NULL. The sg tables are embedded
structs in struct spi_transfer, so they are guaranteed to be non NULL
which makes the if(tx)/if(rx) tests completely bogus. The driver even
sets the SPI_MASTER_MUST_RX / SPI_MASTER_MUST_TX flags which makes sure
the sg tables are not only present but also non empty.
Drop the tests and make the DMA path easier to follow.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
b03c3884ca spi: imx: set MX51_ECSPI_CTRL_SMC bit in setup function
Now that the config function knows whether we are doing DMA or not we
can do the necessary register setup in the config function and no longer
have to do this in the trigger function. With this the trigger function
becomes a no-op for DMA, so instead of testing if we are doing DMA or
not in the trigger function we simply no longer call it in the DMA case.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
d629c2a005 spi: imx: make some register defines simpler
The watermark levels in the DMA register are write only, the driver
should never have to read them back from the hardware. Replace the
current _MASK and _OFFSET defines with defines taking the watermark
level directly.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
c34de7168c spi: imx: remove unnecessary bit clearing in mx51_ecspi_config
This reverts patch 1476253cef (spi: imx: fix ecspi mode setup)
The patch tried to fix something by clearing bits in the cfg variable,
but cfg is initialized to zero on function entry. There are no bits to
clear.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Anton Bondarenko
f12ae171c7 spi: imx: add support for all SPI word width for DMA
DMA transfer for SPI was limited to up to 8 bits word size until now.
Sync in SPI burst size and DMA bus width is necessary to correctly
support 16 and 32 BPW.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
882f329f31 spi: imx: drop unncessary dma_is_inited variable
There's no need for an extra dma_is_inited variable when we can
equally well check for the existence of a DMA channel.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
2b0fd069ec spi: imx: drop unnecessary read/modify/write
When the MX51_ECSPI_DMA is configured we control every single bit
of the register, so there's no need to read/modify/write it. Instead
just write the value we want to have in the register. Also, drop
unnecessary check if we are actually doing DMA. The values written
to the register have no effect in PIO mode and value written there
during the last DMA transfer is still in the register, so we can
equally well always write a value.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
c008a80071 spi: imx: initialize usedma earlier
The SoC specific config function does not know if DMA will be used or
not. This information will be useful to configure the SPI controller
correctly for DMA in following patches, so initialize the usedma
variable before calling into the SoC specific config function.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-26 11:04:14 +09:00
Sascha Hauer
99f1cf1c0c spi: imx: drop fallback to PIO
At the moment the driver decides to fallback to PIO mode the buffers
are already mapped for DMA. It's a bug to access them with the CPU
afterwards, so we cannot just fallback to PIO mode.
It should not be necessary anyway, since we only use DMA when we
verified that it's possible in the fist place, so when prep_slave_sg
fails it's a bug, either in the SDMA driver or in the can_dma
implementation.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-24 17:30:08 +09:00
Anton Bondarenko
4bfe927a11 spi: imx: replace fixed timeout with calculated
Fixed timeout value can fire while transaction is ongoing. This may happen
because there are no strict requirements on SPI transaction duration.
Dynamic timeout value is generated based on SCLK and transaction size.

There is also 4 * SCLK delay between TX bursts related to HW internal CS change.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-20 00:50:47 +09:00
Mark Brown
a4e5efc0d2 Merge remote-tracking branch 'spi/fix/imx' into spi-imx 2016-02-20 00:49:12 +09:00
Mark Brown
499e49b6d3 spi: Fixes for v4.5
A small clutch of driver specific fixes.  The OMAP one is a bit worrying
 since it seems to be triggered by some changes in the runtime PM core
 code and I suspect there's other drivers across that are going to be
 using the same pattern outside of OMAP but nothing seems to be coming up
 in the testing people are doing.
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Merge tag 'spi-fix-v4.5-rc4' into spi-imx

spi: Fixes for v4.5

A small clutch of driver specific fixes.  The OMAP one is a bit worrying
since it seems to be triggered by some changes in the runtime PM core
code and I suspect there's other drivers across that are going to be
using the same pattern outside of OMAP but nothing seems to be coming up
in the testing people are doing.
2016-02-18 14:10:59 +00:00
Sascha Hauer
6aa800ca65 spi: imx: use proper dev_* functions for driver messages
Add a struct device * member to the private driver data and use
it to print messages using dev_* functions rather than pr_*.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-17 14:22:56 +00:00
Anton Bondarenko
390f0ffe92 spi: imx: allow only WML aligned transfers to use DMA
RX DMA tail data handling doesn't work correctly in many cases with current
implementation. It happens because SPI core was setup to generates both RX
and RX TAIL events. And RX TAIL event does not work correctly.
This can be easily verified by sending SPI transaction with size modulus
WML(32 in our case) not equal 0.

Also removing change introduced in f6ee9b582d
since this change only fix usecases with transfer size from 33 to 128 bytes
and doesn't fix 129 bytes and bigger.

This is output from transaction with len 138 bytes in loopback mode at 10Mhz:
TX0000: a3 97 a2 55 53 be f1 fc f9 79 6b 52 14 13 e9 e2
TX0010: 2d 51 8e 1f 56 08 57 27 a7 05 d4 d0 52 82 77 75
TX0020: 1b 99 4a ed 58 3d 6a 52 36 d5 24 4a 68 8e ad 95
TX0030: 5f 3c 35 b5 c4 8c dd 6c 11 32 3d e2 b4 b4 59 cf
TX0040: ce 23 3d 27 df a7 f9 96 fc 1e e0 66 2c 0e 7b 8c
TX0050: ca 30 42 8f bc 9f 7b ce d1 b8 b1 87 ec 8a d6 bb
TX0060: 2e 15 63 0e 3c dc a4 3a 7a 06 20 a7 93 1b 34 dd
TX0070: 4c f5 ec 88 96 68 d6 68 a0 09 6f 8e 93 47 c9 41
TX0080: db ac cf 97 89 f3 51 05 79 71

RX0000: a3 97 a2 55 53 be f1 fc f9 79 6b 52 14 13 e9 e2
RX0010: 2d 51 8e 1f 56 08 57 27 a7 05 d4 d0 52 82 77 75
RX0020: 1b 99 4a ed 58 3d 6a 52 36 d5 24 4a 68 8e ad 95
RX0030: 5f 3c 35 00 00 b5 00 00 00 c4 00 00 8c 00 00 dd
RX0040: 6c 11 32 3d e2 b4 b4 59 cf ce 23 3d 27 df a7 f9
RX0050: 96 fc 1e e0 66 2c 0e 7b 8c ca 30 42 8f 1f 1f bc
RX0060: 9f 7b ce d1 b8 b1 87 ec 8a d6 bb 2e 15 63 0e ed
RX0070: ed 3c 58 58 58 dc 3d 3d a4 6a 6a 3a 52 52 7a 36
RX0080: 06 20 a7 93 1b 34 dd 4c f5 ec

Zeros at offset 33 and 34 caused by reading empty RX FIFO which not possible
if DMA RX read was triggered by RX event. This mean DMA was triggered
by RX TAIL event.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-17 14:22:29 +00:00
Gao Pan
f8efca2f17 spi: imx: fix spi resource leak with dma transfer
In spi_imx_dma_transfer(), when desc_rx = dmaengine_prep_slave_sg()
fails, the context goes to label no_dma and then return. However,
the memory allocated for desc_tx has not been freed yet, which leads
to resource leak.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-22 16:46:58 +00:00
Anton Bondarenko
bf9af08cd5 spi: imx: defer spi initialization, if DMA engine is
If SPI device supports DMA mode, but DMA controller is not yet
available due to e.g. a delay in the corresponding kernel module
initialization, retry to initialize SPI driver later on instead of
falling back into PIO only mode.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-15 22:40:35 +00:00
Anton Bondarenko
3760047a7d spi: imx: return error from dma channel request
On SDMA initialization return exactly the same error, which is
reported by dma_request_slave_channel_reason(), it is a preceding
change to defer SPI DMA initialization, if SDMA module is not yet
available.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-15 22:40:35 +00:00
Anton Bondarenko
4686d1c3d1 spi: imx: enable loopback only for ECSPI controller family
Limit SPI_LOOP mode to ECSPI controller (iMX.51, iMX53 and i.MX6) only since
there is no support in other families specific code for now.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-15 22:40:35 +00:00
Anton Bondarenko
f677f17cce spi: imx: fix loopback mode setup after controller reset
If controller hold in reset it's not possible to write any
register except CTRL. So all other registers must be updated
only after controller bring out from reset.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-15 22:40:35 +00:00
Anton Bondarenko
f8a876176f spi: imx: add function to check for IMX51 family controller
Similar to other controller type checks add check function for
IMX51. It includes IMX53 and IMX6.

Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-07 19:53:35 +00:00