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path: root/drivers/spi/spi-imx.c (follow)
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2017-06-21spi: imx: Check for allocation failure earlierFabio Estevam1-3/+3
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>
2017-06-06spi: imx: rename 'bpw' variablesSascha Hauer1-6/+6
'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>
2017-06-06spi: imx: remove bytes_per_word from private driver structSascha Hauer1-11/+4
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>
2017-06-06spi: imx: drop bogus unnecessary dma configSascha Hauer1-2/+0
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>
2017-06-06spi: imx: put struct spi_imx_config members into driver private structSascha Hauer1-27/+23
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>
2017-06-06spi: imx: Drop unnecessary checkSascha Hauer1-7/+0
__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>
2017-06-06spi: imx: Nothing to do in setupxfer when transfer is NULLSascha Hauer1-5/+5
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>
2017-05-23spi: imx: Revert "spi: imx: dynamic burst length adjust for PIO mode"Sascha Hauer1-155/+8
This reverts commits 8d4a6cad7adb3ddac32cd52635f20e11de11a658 and 179547e143e773f9f866ad3536275ab627711f3a. 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>
2017-05-19spi: imx: fix issue when tx_buf or rx_buf is NULLJiada Wang1-0/+6
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>
2017-05-14spi: imx: dynamic burst length adjust for PIO modeJiada Wang1-8/+149
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>
2017-04-25spi-imx: Implements handling of the SPI_READY mode flag.Leif Middelschulte1-2/+18
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>
2017-01-06spi: imx: adjust watermark level according to transfer lengthJiada Wang1-8/+8
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>
2016-11-02spi: imx: set spi_bus_clk for mx21 and mx27Robert Baldyga1-5/+9
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>
2016-10-24spi: imx: support DMA for imx35Martin Kaiser1-3/+18
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>
2016-09-28spi: imx: fix error return code in spi_imx_probe()Wei Yongjun1-0/+1
Fix to return error code -EINVAL if no CS GPIOs available instead of 0, as done elsewhere in this function. Fixes: f13d4e189d20 ("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>
2016-09-26spi: imx: Gracefully handle NULL master->cs_gpiosMarek Vasut1-0/+5
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>
2016-09-14spi: imx: support loopback mode on imx35Martin Kaiser1-1/+11
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>
2016-09-14spi: imx: set spi_bus_clk for mx1, mx31 and mx35Martin Kaiser1-5/+12
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>
2016-06-21spi: imx: wait_for_completion_timeout(..) for PIO transfersChristian Gmeiner1-1/+11
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>
2016-06-14spi: imx: Remove "maybe_unused" attributesAlexander Shiyan1-24/+21
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>
2016-06-14spi: imx: Remove unnecessary field "mode" from struct spi_imx_configAlexander Shiyan1-14/+12
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>
2016-06-14spi: imx: Using existing properties for chipselectsAlexander Shiyan1-66/+58
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>
2016-03-17spi: imx: Fix possible NULL pointer derefSascha Hauer1-1/+5
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>
2016-03-17spi: imx: only do necessary changes to ECSPIx_CONFIGREGKnut Wohlrab1-1/+9
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>
2016-02-26spi: imx: drop bogus tests for rx/tx bufs in DMA transferSascha Hauer1-48/+34
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>
2016-02-26spi: imx: set MX51_ECSPI_CTRL_SMC bit in setup functionSascha Hauer1-15/+6
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>
2016-02-26spi: imx: make some register defines simplerSascha Hauer1-9/+6
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>
2016-02-26spi: imx: remove unnecessary bit clearing in mx51_ecspi_configSascha Hauer1-7/+0
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>
2016-02-26spi: imx: add support for all SPI word width for DMAAnton Bondarenko1-27/+91
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>
2016-02-26spi: imx: drop unncessary dma_is_inited variableSascha Hauer1-5/+1
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>
2016-02-26spi: imx: drop unnecessary read/modify/writeSascha Hauer1-21/+10
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>
2016-02-26spi: imx: initialize usedma earlierSascha Hauer1-7/+8
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>
2016-02-24spi: imx: drop fallback to PIOSascha Hauer1-13/+6
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>
2016-02-20spi: imx: replace fixed timeout with calculatedAnton Bondarenko1-3/+21
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>
2016-02-20Merge remote-tracking branch 'spi/fix/imx' into spi-imxMark Brown1-15/+2
2016-02-18Merge tag 'spi-fix-v4.5-rc4' into spi-imxMark Brown1-3/+5
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.
2016-02-17spi: imx: use proper dev_* functions for driver messagesSascha Hauer1-15/+12
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>
2016-02-17spi: imx: allow only WML aligned transfers to use DMAAnton Bondarenko1-15/+2
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 f6ee9b582d2db652497b73c1f117591dfb6d3a90 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>
2016-01-22spi: imx: fix spi resource leak with dma transferGao Pan1-3/+5
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>
2015-12-15spi: imx: defer spi initialization, if DMA engine isAnton Bondarenko1-0/+3
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>
2015-12-15spi: imx: return error from dma channel requestAnton Bondarenko1-11/+16
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>
2015-12-15spi: imx: enable loopback only for ECSPI controller familyAnton Bondarenko1-5/+6
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>
2015-12-15spi: imx: fix loopback mode setup after controller resetAnton Bondarenko1-1/+3
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>
2015-12-07spi: imx: add function to check for IMX51 family controllerAnton Bondarenko1-3/+8
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>
2015-12-07spi: imx: replace multiple watermarks with single for RX, TX and RXTAnton Bondarenko1-16/+13
There is no need to have different watermarks levels since they are the same. Merge them into one WML parameter. Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-07spi: imx: reorder HW operations enable order to avoid possible RX data lossAnton Bondarenko1-2/+10
The overflow may happen due to rescheduling for another task and/or interrupt if we enable SPI HW before starting RX DMA. So RX DMA enabled first to make sure data would be read out from FIFO ASAP. TX DMA enabled next to start filling TX FIFO with new data. And finaly SPI HW enabled to start actual data transfer. The risk rise in case of heavy system load and high SPI clock. Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-07spi: imx: terminate RX DMA transaction in case of TX DMA timeoutAnton Bondarenko1-0/+1
Not only TX DMA should be terminated, but RX DMA also. It's required to avoid accidential DMA memory writes from RX DMA channel and properly terminate transaction. Signed-off-by: Anton Bondarenko <anton.bondarenko.sama@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-04spi: imx: Add loopback mode supportFabio Estevam1-2/+13
Loopback mode can be activated by setting bit LBC (LoopBack Control) of register ECSPI_TESTREG. Add support for it. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-23spi: imx: fix ecspi mode setupAndrew Y. Kuksov1-0/+7
Fixed problem with setting spi mode 0 or 1 after setting mode 2 or 3 SPI_MODE_0 and SPI_MODE_1 requires clock low when inactive. SPI_MODE_2 and SPI_MODE_3 requires clk high when inactive. Currently driver can just set bits in fields SCLK_PHA (SPI Clock/Data Phase Control), SCLK_POL (SPI Clock Polarity Control), SCLK_CTL (controls the inactive state of SCLK) ans SS_POL (SPI SS Polarity Select) of ECSPIx_CONFIGREG register. This patch allows driver to clear corresponding bits in these fields. Signed-off-by: Andrew Y. Kuksov <qxovxp@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-24spi: imx: Fix small DMA transfersSascha Hauer1-2/+3
DMA transfers must be greater than the watermark level size. spi_imx->rx_wml and spi_imx->tx_wml contain the watermark level in 32bit words whereas struct spi_transfer contains the transfer len in bytes. Fix the check if DMA is possible for a transfer accordingly. This fixes transfers with sizes between 33 and 128 bytes for which previously was claimed that DMA is possible. Fixes: f62caccd12c17e4 (spi: spi-imx: add DMA support) Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>