summaryrefslogtreecommitdiff
path: root/drivers/spi/spi-fsl-lpspi.c
AgeCommit message (Collapse)Author
2021-04-09spi: fsl-lpspi: Fix PM reference leak in lpspi_prepare_xfer_hardware()Wang Li
pm_runtime_get_sync will increment pm usage counter even it failed. Forgetting to putting operation will result in reference leak here. Fix it by replacing it with pm_runtime_resume_and_get to keep usage counter balanced. Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wang Li <wangli74@huawei.com> Link: https://lore.kernel.org/r/20210409095430.29868-1-wangli74@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-12spi: lpspi: Fix use-after-free on unbindLukas Wunner
Normally the last reference on an spi_controller is released by spi_unregister_controller(). In the case of the i.MX lpspi driver, the spi_controller is registered with devm_spi_register_controller(), so spi_unregister_controller() is invoked automatically after the driver has unbound. However the driver already releases the last reference in fsl_lpspi_remove() through a gratuitous call to spi_master_put(), causing a use-after-free when spi_unregister_controller() is subsequently invoked by the devres framework. Fix by dropping the superfluous spi_master_put(). Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: <stable@vger.kernel.org> # v5.2+ Cc: Han Xu <han.xu@nxp.com> Link: https://lore.kernel.org/r/ab3c0b18bd820501a12c85e440006e09ec0e275f.1604874488.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-18spi: lpspi: Remove CONFIG_PM_SLEEP ifdeferyFabio Estevam
Use __maybe_unused for the suspend()/resume() hooks and get rid of the CONFIG_PM_SLEEP ifdefery to improve the code. Signed-off-by: Fabio Estevam <festevam@gmail.com> Link: https://lore.kernel.org/r/20200817235812.19518-1-festevam@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-29spi: lpspi: fix using CS discontinuously on i.MX8DXLEVKClark Wang
SPI common code does not support using CS discontinuously for now. However, i.MX8DXL-EVK only uses CS1 without CS0. Therefore, add a flag is_only_cs1 to set the correct TCR[PCS]. Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Link: https://lore.kernel.org/r/20200727031448.31661-4-xiaoning.wang@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-29spi: lpspi: remove unused fsl_lpspi->chipselectClark Wang
The cs-gpio is initailized by spi_get_gpio_descs() now. Remove the chipselect. Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Link: https://lore.kernel.org/r/20200727031448.31661-3-xiaoning.wang@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-29spi: lpspi: Fix kernel warning dump when probe fail after calling spi_registerClark Wang
Calling devm_spi_register_controller() too early will cause problem. When probe failed occurs after calling devm_spi_register_controller(), the call of spi_controller_put() will trigger the following warning dump. [ 2.092138] ------------[ cut here ]------------ [ 2.096876] kernfs: can not remove 'uevent', no directory [ 2.102440] WARNING: CPU: 0 PID: 181 at fs/kernfs/dir.c:1503 kernfs_remove_by_name_ns+0xa0/0xb0 [ 2.111142] Modules linked in: [ 2.114207] CPU: 0 PID: 181 Comm: kworker/0:7 Not tainted 5.4.24-05024-g775c6e8a738c-dirty #1314 [ 2.122991] Hardware name: Freescale i.MX8DXL EVK (DT) [ 2.128141] Workqueue: events deferred_probe_work_func [ 2.133281] pstate: 60000005 (nZCv daif -PAN -UAO) [ 2.138076] pc : kernfs_remove_by_name_ns+0xa0/0xb0 [ 2.142958] lr : kernfs_remove_by_name_ns+0xa0/0xb0 [ 2.147837] sp : ffff8000122bba70 [ 2.151145] x29: ffff8000122bba70 x28: ffff8000119d6000 [ 2.156462] x27: 0000000000000000 x26: ffff800011edbce8 [ 2.161779] x25: 0000000000000000 x24: ffff00003ae4f700 [ 2.167096] x23: ffff000010184c10 x22: ffff00003a3d6200 [ 2.172412] x21: ffff800011a464a8 x20: ffff000010126a68 [ 2.177729] x19: ffff00003ae5c800 x18: 000000000000000e [ 2.183046] x17: 0000000000000001 x16: 0000000000000019 [ 2.188362] x15: 0000000000000004 x14: 000000000000004c [ 2.193679] x13: 0000000000000000 x12: 0000000000000001 [ 2.198996] x11: 0000000000000000 x10: 00000000000009c0 [ 2.204313] x9 : ffff8000122bb7a0 x8 : ffff00003a3d6c20 [ 2.209630] x7 : ffff00003a3d6380 x6 : 0000000000000001 [ 2.214946] x5 : 0000000000000001 x4 : ffff00003a05eb18 [ 2.220263] x3 : 0000000000000005 x2 : ffff8000119f1c48 [ 2.225580] x1 : 2bcbda323bf5a800 x0 : 0000000000000000 [ 2.230898] Call trace: [ 2.233345] kernfs_remove_by_name_ns+0xa0/0xb0 [ 2.237879] sysfs_remove_file_ns+0x14/0x20 [ 2.242065] device_del+0x12c/0x348 [ 2.245555] device_unregister+0x14/0x30 [ 2.249492] spi_unregister_controller+0xac/0x120 [ 2.254201] devm_spi_unregister+0x10/0x18 [ 2.258304] release_nodes+0x1a8/0x220 [ 2.262055] devres_release_all+0x34/0x58 [ 2.266069] really_probe+0x1b8/0x318 [ 2.269733] driver_probe_device+0x54/0xe8 [ 2.273833] __device_attach_driver+0x80/0xb8 [ 2.278194] bus_for_each_drv+0x74/0xc0 [ 2.282034] __device_attach+0xdc/0x138 [ 2.285876] device_initial_probe+0x10/0x18 [ 2.290063] bus_probe_device+0x90/0x98 [ 2.293901] deferred_probe_work_func+0x64/0x98 [ 2.298442] process_one_work+0x198/0x320 [ 2.302451] worker_thread+0x1f0/0x420 [ 2.306208] kthread+0xf0/0x120 [ 2.309352] ret_from_fork+0x10/0x18 [ 2.312927] ---[ end trace 58abcdfae01bd3c7 ]--- So put this function at the end of the probe sequence. Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Link: https://lore.kernel.org/r/20200727031448.31661-2-xiaoning.wang@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-22spi: lpspi: fix the imbalance of runtime pm function callClark Wang
Call the put function after probe successfully. Otherwise, the lpspi module will keep active status until the first spi transfer called. Disable runtime pm when probe fails. There is no need to active runtime pm after probe failed. Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Link: https://lore.kernel.org/r/20200714075251.12777-2-xiaoning.wang@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-13spi: imx/fsl-lpspi: Convert to GPIO descriptorsLinus Walleij
This converts the two Freescale i.MX SPI drivers Freescale i.MX (CONFIG_SPI_IMX) and Freescale i.MX LPSPI (CONFIG_SPI_FSL_LPSPI) to use GPIO descriptors handled in the SPI core for GPIO chip selects whether defined in the device tree or a board file. The reason why both are converted at the same time is that they were both using the same platform data and platform device population helpers when using board files intertwining the code so this gives a cleaner cut. The platform device creation was passing a platform data container from each boardfile down to the driver using struct spi_imx_master from <linux/platform_data/spi-imx.h>, but this was only conveying the number of chipselects and an int * array of the chipselect GPIO numbers. The imx27 and imx31 platforms had code passing the now-unused platform data when creating the platform devices, this has been repurposed to pass around GPIO descriptor tables. The platform data struct that was just passing an array of integers and number of chip selects for the GPIO lines has been removed. The number of chipselects used to be passed from the board file, because this number also limits the number of native chipselects that the platform can use. To deal with this we just augment the i.MX (CONFIG_SPI_IMX) driver to support 3 chipselects if the platform does not define "num-cs" as a device property (such as from the device tree). This covers all the legacy boards as these use <= 3 native chip selects (or GPIO lines, and in that case the number of chip selects is determined by the core from the number of available GPIO lines). Any new boards should use device tree, so this is a reasonable simplification to cover all old boards. The LPSPI driver never assigned the number of chipselects and thus always fall back to the core default of 1 chip select if no GPIOs are defined in the device tree. The Freescale i.MX driver was already partly utilizing the SPI core to obtain the GPIO numbers from the device tree, so this completes the transtion to let the core handle all of it. All board files and the core i.MX boardfile registration code is augmented to account for these changes. This has been compile-tested with the imx_v4_v5_defconfig and the imx_v6_v7_defconfig. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Robin Gong <yibin.gong@nxp.com> Cc: Trent Piepho <tpiepho@impinj.com> Cc: Clark Wang <xiaoning.wang@nxp.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Link: https://lore.kernel.org/r/20200625200252.207614-1-linus.walleij@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
2020-05-26spi: spi-fsl-lpspi: Fix runtime PM imbalance on errorDinghao Liu
pm_runtime_get_sync() increments the runtime PM usage counter even when it returns an error code. Thus a pairing decrement is needed on the error handling path to keep the counter balanced. Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn> Link: https://lore.kernel.org/r/20200523133859.5625-1-dinghao.liu@zju.edu.cn Signed-off-by: Mark Brown <broonie@kernel.org>
2020-04-14spi: spi-fsl-lpspi: Fix indentation and open brace should be on the previous ↵Aishwarya R
line Resolved open brace { should be on the previous line checkpatch error and fix the indentation Signed-off-by: Aishwarya R <aishwaryarj100@gmail.com> Link: https://lore.kernel.org/r/20200407125557.6520-1-aishwaryarj100@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-03-23spi: spi-fsl-lpspi: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200320232515.GA24800@embeddedor.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-03-03spi: fsl-lpspi: remove unneeded arrayOleksandr Suvorov
- replace the array with the shift operation - remove the extra comparing operation. Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> Link: https://lore.kernel.org/r/20200220141143.3902922-2-oleksandr.suvorov@toradex.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-01-14spi: fsl-lpspi: fix only one cs-gpio workingPhilippe Schenker
Why it does not work at the moment: - num_chipselect sets the number of cs-gpios that are in the DT. This comes from drivers/spi/spi.c - num_chipselect gets set with devm_spi_register_controller, that is called in drivers/spi/spi.c - devm_spi_register_controller got called after num_chipselect has been used. How this commit fixes the issue: - devm_spi_register_controller gets called before num_chipselect is being used. Fixes: c7a402599504 ("spi: lpspi: use the core way to implement cs-gpio function") Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com> Link: https://lore.kernel.org/r/20191204141312.1411251-1-philippe.schenker@toradex.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-12-25spi: fsl-lpspi: use true,false for bool variablezhengbin
Fixes coccicheck warning: drivers/spi/spi-fsl-lpspi.c:472:2-19: WARNING: Assignment of 0/1 to bool variable drivers/spi/spi-fsl-lpspi.c:474:2-19: WARNING: Assignment of 0/1 to bool variable Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Link: https://lore.kernel.org/r/1577159526-33689-2-git-send-email-zhengbin13@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-11-15spi: fsl-lpspi: Use dma_request_chan() directly for channel requestPeter Ujfalusi
dma_request_slave_channel_reason() is: #define dma_request_slave_channel_reason(dev, name) \ dma_request_chan(dev, name) Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20191113094256.1108-4-peter.ujfalusi@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-08Merge branch 'for-5.4' of ↵Mark Brown
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.5
2019-10-01spi: lpspi: fix memory leak in fsl_lpspi_probeNavid Emamdoost
In fsl_lpspi_probe an SPI controller is allocated either via spi_alloc_slave or spi_alloc_master. In all but one error cases this controller is put by going to error handling code. This commit fixes the case when pm_runtime_get_sync fails and it should go to the error handling path. Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com> Link: https://lore.kernel.org/r/20190930034602.1467-1-navid.emamdoost@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-01spi: fsl-lpspi: clean up indentation issueColin Ian King
The complete call is indented incorrectly, remove the extraneous tabs. Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20190926113701.26986-1-colin.king@canonical.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08spi: fsl-lpspi: Clean up fsl_lpspi_probeAxel Lin
Use is_slave local variable to avoid calling of_property_read_bool() twice. Remove redudant assignment for controller->bus_num, set it once is enough. Move setting controller->bits_per_word_mask close to the code init other controller fields. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08spi: fsl-lpspi: Fix build warning when !CONFIG_PMAxel Lin
Add #ifdef CONFIG_PM guard to fix build warning when !CONFIG_PM drivers/spi/spi-fsl-lpspi.c:810:12: warning: ‘fsl_lpspi_runtime_suspend’ defined but not used [-Wunused-function] static int fsl_lpspi_runtime_suspend(struct device *dev) ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/spi/spi-fsl-lpspi.c:789:12: warning: ‘fsl_lpspi_runtime_resume’ defined but not used [-Wunused-function] static int fsl_lpspi_runtime_resume(struct device *dev) ^~~~~~~~~~~~~~~~~~~~~~~~ Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-08spi: fsl-lpspi: Fix problematic dev_set_drvdata callAxel Lin
The original code already set controller as drvdata: platform_set_drvdata(pdev, controller); But commit 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") added dev_set_drvdata(&pdev->dev, fsl_lpspi); so fsl_lpspi_remove() will get wrong pointer by platform_get_drvdata(). Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-05Merge branch 'spi-5.1' into spi-5.2Mark Brown
2019-04-03spi: lpspi: add missing complete in abort func at dma modeClark Wang
Add the missing complete operations for dma_completion to fix the problem of blocking at the wait_for_completion_interruptible() function when use spi_slave_abort(). Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-21spi: lpspi: fix dataloss when SS is inactivated between every wordsClark Wang
If we don't use CONT to keep SS activated or use DMA mode without cs-gpio, SS will be inactivated between every words. The word here means the data sent once which length can be set as 1/2/4 bytes. In the isr function, we read the FSR_RXCOUNT just behind the fsl_lpspi_read_rx_fifo. This causes the value of FSR_RXCOUNT cannot reflect whether there is still data not sent timely. So do this judgement by FSR_TXCOUNT. Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-19spi: lpspi: fsl_lpspi_runtime_resume() can be statickbuild test robot
Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Signed-off-by: kbuild test robot <lkp@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-18spi: lpspi: Code cleanupClark Wang
Delete the extra space. Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-03-18spi: lpspi: Add the missing NULL checkClark Wang
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>
2019-03-18spi: lpspi: add dma mode supportClark Wang
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>
2019-03-18spi: lpspi: use the core way to implement cs-gpio functionClark Wang
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>
2019-03-18spi: lpspi: add the error info of transfer speed settingClark Wang
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>
2019-03-18spi: lpspi: enable runtime pm for lpspiHan Xu
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>
2019-03-18spi: lpspi: Add i.MX8 boards support for lpspiClark Wang
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>
2019-01-07spi: lpspi: Fix CLK pin becomes low before one transferClark Wang
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>
2019-01-07spi: lpspi: Fix wrong transmission when don't use CONTClark Wang
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>
2019-01-07spi: lpspi: Improve the stability of lpspi data transmissionClark Wang
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>
2018-12-13spi: lpspi: Let watermark change with send data lengthClark Wang
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>
2018-12-13spi: lpspi: Add slave mode supportClark Wang
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>
2018-12-13spi: lpspi: Replace all "master" with "controller"Clark Wang
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>
2018-10-10spi: fsl-lpspi: Prevent FIFO under/overrun by defaultHieu Tran Dang
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>
2018-05-03spi: lpspi: Switch to SPDX identifierFabio Estevam
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>
2017-01-09spi: fsl-lpspi: fix indentation errorGao Pan
This patch fixes the indentation error in spi-fsl-lpspi.c. Signed-off-by: Gao Pan <pandy.gao@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-14spi: fsl-lpspi: Pre-initialize ret in fsl_lpspi_transfer_one_msg()Geert Uytterhoeven
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>
2016-12-05spi: fsl-lpspi: quit reading rx fifo under error conditionGao Pan
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>
2016-12-05spi: fsl-lpspi: use GPL as module licenseGao Pan
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>
2016-11-30spi: fsl-lpspi: read lpspi tx/rx fifo size in probe()Gao Pan
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>
2016-11-30spi: fsl-lpspi: use wait_for_completion_timeout() while waiting transfer doneGao Pan
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>
2016-11-25spi: imx: replace schedule() with cond_resched()Gao Pan
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>
2016-11-25spi: imx: fix potential shift truncationGao Pan
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>
2016-11-25spi: imx: use prepare_transfer_hardware() for lpspiGao Pan
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>
2016-11-22spi: imx: add lpspi bus driverGao Pan
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>