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path: root/drivers/spi/spidev.c
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2021-05-11spi: spidev: Use SPI_MODE_X_MASKAndy Shevchenko
Use SPI_MODE_X_MASK instead of open coded variant. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20210510131217.49357-2-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
2021-04-20spidev: Add Micron SPI NOR Authenta device compatibleShivamurthy Shastri
Add compatible string for Micron SPI NOR Authenta device. Signed-off-by: Shivamurthy Shastri <sshivamurthy@micron.com> Link: https://lore.kernel.org/r/20210419204015.1769-1-sshivamurthy@micron.com Signed-off-by: Mark Brown <broonie@kernel.org>
2021-01-25spidev: Add cisco device compatibleDaniel Walker
Add compatible string for Cisco device present on the Cisco Petra platform. Signed-off-by: Daniel Walker <danielwa@cisco.com> Cc: xe-linux-external@cisco.com Link: https://lore.kernel.org/r/20210121231237.30664-2-danielwa@cisco.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-09spi: spidev: Remove redundant initialization of variable statusJay Fang
In spidev_read() and spidev_write(), the variable status is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Signed-off-by: Jay Fang <f.fangjian@huawei.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/1599631704-53232-1-git-send-email-f.fangjian@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-07-28spi: spidev: Align buffers for DMAChristian Eggers
Simply copying all xfers from userspace into one bounce buffer causes alignment problems if the SPI controller uses DMA. Ensure that all transfer data blocks within the rx and tx bounce buffers are aligned for DMA (according to ARCH_KMALLOC_MINALIGN). Alignment may increase the usage of the bounce buffers. In some cases, the buffers may need to be increased using the "bufsiz" module parameter. Signed-off-by: Christian Eggers <ceggers@arri.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200728100832.24788-1-ceggers@arri.de Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-18spi: spidev: fix a potential use-after-free in spidev_release()Zhenzhong Duan
If an spi device is unbounded from the driver before the release process, there will be an NULL pointer reference when it's referenced in spi_slave_abort(). Fix it by checking it's already freed before reference. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com> Link: https://lore.kernel.org/r/20200618032125.4650-2-zhenzhong.duan@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-18spi: spidev: fix a race between spidev_release and spidev_removeZhenzhong Duan
Imagine below scene, spidev is referenced after it's freed. spidev_release() spidev_remove() ... spin_lock_irq(&spidev->spi_lock); spidev->spi = NULL; spin_unlock_irq(&spidev->spi_lock); mutex_lock(&device_list_lock); dofree = (spidev->spi == NULL); if (dofree) kfree(spidev); mutex_unlock(&device_list_lock); mutex_lock(&device_list_lock); list_del(&spidev->device_entry); device_destroy(spidev_class, spidev->devt); clear_bit(MINOR(spidev->devt), minors); if (spidev->users == 0) kfree(spidev); mutex_unlock(&device_list_lock); Fix it by resetting spidev->spi in device_list_lock's protection. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com> Link: https://lore.kernel.org/r/20200618032125.4650-1-zhenzhong.duan@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-04-16spi: spidev: Add support for Octal mode data transfersGeert Uytterhoeven
Include the flags for Octal mode data transfers in the mask, so userspace can set them. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20200416101835.14573-2-geert+renesas@glider.be Signed-off-by: Mark Brown <broonie@kernel.org>
2020-03-02spi: spidev: fix speed setting messageOleksandr Suvorov
The message of max device speed setting is shown when an error in spi_setup() occurs. Instead, it should be shown when the setup call succeeds. Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> Link: https://lore.kernel.org/r/20200229161841.89144-3-oleksandr.suvorov@toradex.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-03-02spi: spidev: fix a debug message valueOleksandr Suvorov
The debug message in spidev_message() can show wrong xfer speed. It happens if the initial (came from DT) and set with ioctl call spidev speeds are different (spidev->speed_hz != spi->max_speed_hz) and one sends a message with ioctl call and the field of speed is uninitialized (u_tmp->speed_hz == 0). In this case the kernel shows the spi->max_speed_hz value instead of correct spidev->speed_hz. ... set the max speed with an ioctl call: [ 1227.702714] spidev spi0.0: setup mode 0, 32 bits/w, 20000000 Hz max --> 0 (real speed sets to 20000000Hz) send a message with an ioctl call: [ 1227.731801] spidev spi0.0: xfer len 4096 tx 32bits 0 usec 10000000Hz (debug message shows 10000000Hz that is the original max speed of this spidev came from DT) ... Fix the data source for the debug message. Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> Link: https://lore.kernel.org/r/20200229161841.89144-2-oleksandr.suvorov@toradex.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-02-21spi: spidev: Fix CS polarity if GPIO descriptors are usedLukas Wunner
Commit f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs") amended of_spi_parse_dt() to always set SPI_CS_HIGH for SPI slaves whose Chip Select is defined by a "cs-gpios" devicetree property. This change broke userspace applications which issue an SPI_IOC_WR_MODE ioctl() to an spidev: Chip Select polarity will be incorrect unless the application is changed to set SPI_CS_HIGH. And once changed, it will be incompatible with kernels not containing the commit. Fix by setting SPI_CS_HIGH in spidev_ioctl() (under the same conditions as in of_spi_parse_dt()). Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs") Reported-by: Simon Han <z.han@kunbus.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/fca3ba7cdc930cd36854666ceac4fbcf01b89028.1582027457.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org # v5.1+
2019-10-15spi: spidev: use new `delay` field for spi transfersAlexandru Ardelean
The `delay` field has type `struct spi_delay`. This allows users to specify nano-second or clock-cycle delays (if needed). Converting to use `delay` is straightforward: it's just assigning the value to `delay.value` and hard-coding the `delay.unit` to `SPI_DELAY_UNIT_USECS`. This keeps the uapi for spidev un-changed. Changing it can be part of another changeset and discussion. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-14-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-10-15spi: spidev: use new `word_delay` field for spi transfersAlexandru Ardelean
The `word_delay` field had it's type changed to `struct spi_delay`. This allows users to specify nano-second or clock-cycle delays (if needed). Converting to use `word_delay` is straightforward: it's just assigning the value to `word_delay.value` and hard-coding the `word_delay.unit` to `SPI_DELAY_UNIT_USECS` This keeps the uapi for spidev un-changed. Changing it can be part of another changeset and discussion. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Link: https://lore.kernel.org/r/20190926105147.7839-7-alexandru.ardelean@analog.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-09-25spi: Add call to spi_slave_abort() function when spidev driver is releasedLukasz Majewski
This change is necessary for spidev devices (e.g. /dev/spidev3.0) working in the slave mode (like NXP's dspi driver for Vybrid SoC). When SPI HW works in this mode - the master is responsible for providing CS and CLK signals. However, when some fault happens - like for example distortion on SPI lines - the SPI Linux driver needs a chance to recover from this abnormal situation and prepare itself for next (correct) transmission. This change doesn't pose any threat on drivers working in master mode as spi_slave_abort() function checks if SPI slave mode is supported. Signed-off-by: Lukasz Majewski <lukma@denx.de> Link: https://lore.kernel.org/r/20190924110547.14770-2-lukma@denx.de Signed-off-by: Mark Brown <broonie@kernel.org> Reported-by: kbuild test robot <lkp@intel.com> Link: https://lore.kernel.org/r/20190925091143.15468-2-lukma@denx.de Signed-off-by: Mark Brown <broonie@kernel.org>
2019-06-10Merge tag 'v5.2-rc4' into spi-5.3Mark Brown
Linux 5.2-rc4
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157Thomas Gleixner
Based on 3 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-29spidev: Add M53Menlo CPLD compatibleMarek Vasut
Add compatible string for Menlosystems CPLD present on the M53Menlo board. This CPLD is used to communicate with various custom sensors. Signed-off-by: Marek Vasut <marex@denx.de> To: linux-spi@vger.kernel.org Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-20spi: spidev: Add dhcom-board to compatibility listChristoph Niedermaier
Prepare to use devices on the external SPI interface on a DH electronics Development Board. Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-07Merge tag 'stream_open-5.2' of https://lab.nexedi.com/kirr/linuxLinus Torvalds
Pull stream_open conversion from Kirill Smelkov: - remove unnecessary double nonseekable_open from drivers/char/dtlk.c as noticed by Pavel Machek while reviewing nonseekable_open -> stream_open mass conversion. - the mass conversion patch promised in commit 10dce8af3422 ("fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock") and is automatically generated by running $ make coccicheck MODE=patch COCCI=scripts/coccinelle/api/stream_open.cocci I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. More details on this in the patch. - finally, change VFS to pass ppos=NULL into .read/.write for files that declare themselves streams. It was suggested by Rasmus Villemoes and makes sure that if ppos starts to be erroneously used in a stream file, such bug won't go unnoticed and will produce an oops instead of creating illusion of position change being taken into account. Note: this patch does not conflict with "fuse: Add FOPEN_STREAM to use stream_open()" that will be hopefully coming via FUSE tree, because fs/fuse/ uses new-style .read_iter/.write_iter, and for these accessors position is still passed as non-pointer kiocb.ki_pos . * tag 'stream_open-5.2' of https://lab.nexedi.com/kirr/linux: vfs: pass ppos=NULL to .read()/.write() of FMODE_STREAM files *: convert stream-like files from nonseekable_open -> stream_open dtlk: remove double call to nonseekable_open
2019-05-06*: convert stream-like files from nonseekable_open -> stream_openKirill Smelkov
Using scripts/coccinelle/api/stream_open.cocci added in 10dce8af3422 ("fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock"), search and convert to stream_open all in-kernel nonseekable_open users for which read and write actually do not depend on ppos and where there is no other methods in file_operations which assume @offset access. I've verified each generated change manually - that it is correct to convert - and each other nonseekable_open instance left - that it is either not correct to convert there, or that it is not converted due to current stream_open.cocci limitations. The script also does not convert files that should be valid to convert, but that currently have .llseek = noop_llseek or generic_file_llseek for unknown reason despite file being opened with nonseekable_open (e.g. drivers/input/mousedev.c) Among cases converted 14 were potentially vulnerable to read vs write deadlock (see details in 10dce8af3422): drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/infiniband/core/user_mad.c:988:1-17: ERROR: umad_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/input/misc/uinput.c:401:1-17: ERROR: uinput_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write(); change nonseekable_open -> stream_open to fix. and the rest were just safe to convert to stream_open because their read and write do not use ppos at all and corresponding file_operations do not have methods that assume @offset file access(*): arch/powerpc/platforms/52xx/mpc52xx_gpt.c:631:8-24: WARNING: mpc52xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_ibox_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_ibox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_mbox_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_mbox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_wbox_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. arch/powerpc/platforms/cell/spufs/file.c:591:8-24: WARNING: spufs_wbox_stat_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. arch/um/drivers/harddog_kern.c:88:8-24: WARNING: harddog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. arch/x86/kernel/cpu/microcode/core.c:430:33-49: WARNING: microcode_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/ds1620.c:215:8-24: WARNING: ds1620_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/dtlk.c:301:1-17: WARNING: dtlk_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/ipmi/ipmi_watchdog.c:840:9-25: WARNING: ipmi_wdog_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/pcmcia/scr24x_cs.c:95:8-24: WARNING: scr24x_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/char/tb0219.c:246:9-25: WARNING: tb0219_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/firewire/nosy.c:306:8-24: WARNING: nosy_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/hwmon/fschmd.c:840:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/hwmon/w83793.c:1344:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/infiniband/core/ucma.c:1747:8-24: WARNING: ucma_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/infiniband/core/ucm.c:1178:8-24: WARNING: ucm_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/infiniband/core/uverbs_main.c:1086:8-24: WARNING: uverbs_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/input/joydev.c:282:1-17: WARNING: joydev_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/pci/switch/switchtec.c:393:1-17: WARNING: switchtec_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/platform/chrome/cros_ec_debugfs.c:135:8-24: WARNING: cros_ec_console_log_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/rtc/rtc-ds1374.c:470:9-25: WARNING: ds1374_wdt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/rtc/rtc-m41t80.c:805:9-25: WARNING: wdt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/s390/char/tape_char.c:293:2-18: WARNING: tape_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/s390/char/zcore.c:194:8-24: WARNING: zcore_reipl_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/s390/crypto/zcrypt_api.c:528:8-24: WARNING: zcrypt_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/spi/spidev.c:594:1-17: WARNING: spidev_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/staging/pi433/pi433_if.c:974:1-17: WARNING: pi433_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/acquirewdt.c:203:8-24: WARNING: acq_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/advantechwdt.c:202:8-24: WARNING: advwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/alim1535_wdt.c:252:8-24: WARNING: ali_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/alim7101_wdt.c:217:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ar7_wdt.c:166:8-24: WARNING: ar7_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/at91rm9200_wdt.c:113:8-24: WARNING: at91wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ath79_wdt.c:135:8-24: WARNING: ath79_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/bcm63xx_wdt.c:119:8-24: WARNING: bcm63xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/cpu5wdt.c:143:8-24: WARNING: cpu5wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/cpwd.c:397:8-24: WARNING: cpwd_fops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/eurotechwdt.c:319:8-24: WARNING: eurwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/f71808e_wdt.c:528:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/gef_wdt.c:232:8-24: WARNING: gef_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/geodewdt.c:95:8-24: WARNING: geodewdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ib700wdt.c:241:8-24: WARNING: ibwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ibmasr.c:326:8-24: WARNING: asr_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/indydog.c:80:8-24: WARNING: indydog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/intel_scu_watchdog.c:307:8-24: WARNING: intel_scu_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/iop_wdt.c:104:8-24: WARNING: iop_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/it8712f_wdt.c:330:8-24: WARNING: it8712f_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ixp4xx_wdt.c:68:8-24: WARNING: ixp4xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/ks8695_wdt.c:145:8-24: WARNING: ks8695wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/m54xx_wdt.c:88:8-24: WARNING: m54xx_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/machzwd.c:336:8-24: WARNING: zf_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/mixcomwd.c:153:8-24: WARNING: mixcomwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/mtx-1_wdt.c:121:8-24: WARNING: mtx1_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/mv64x60_wdt.c:136:8-24: WARNING: mv64x60_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/nuc900_wdt.c:134:8-24: WARNING: nuc900wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/nv_tco.c:164:8-24: WARNING: nv_tco_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pc87413_wdt.c:289:8-24: WARNING: pc87413_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd.c:698:8-24: WARNING: pcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd.c:737:8-24: WARNING: pcwd_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_pci.c:581:8-24: WARNING: pcipcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_pci.c:623:8-24: WARNING: pcipcwd_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_usb.c:488:8-24: WARNING: usb_pcwd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pcwd_usb.c:527:8-24: WARNING: usb_pcwd_temperature_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pika_wdt.c:121:8-24: WARNING: pikawdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/pnx833x_wdt.c:119:8-24: WARNING: pnx833x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/rc32434_wdt.c:153:8-24: WARNING: rc32434_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/rdc321x_wdt.c:145:8-24: WARNING: rdc321x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/riowd.c:79:1-17: WARNING: riowd_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sa1100_wdt.c:62:8-24: WARNING: sa1100dog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc60xxwdt.c:211:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc7240_wdt.c:139:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc8360.c:274:8-24: WARNING: sbc8360_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc_epx_c3.c:81:8-24: WARNING: epx_c3_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sbc_fitpc2_wdt.c:78:8-24: WARNING: fitpc2_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sb_wdog.c:108:1-17: WARNING: sbwdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sc1200wdt.c:181:8-24: WARNING: sc1200wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sc520_wdt.c:261:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/sch311x_wdt.c:319:8-24: WARNING: sch311x_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/scx200_wdt.c:105:8-24: WARNING: scx200_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/smsc37b787_wdt.c:369:8-24: WARNING: wb_smsc_wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/w83877f_wdt.c:227:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/w83977f_wdt.c:301:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wafer5823wdt.c:200:8-24: WARNING: wafwdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/watchdog_dev.c:828:8-24: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdrtas.c:379:8-24: WARNING: wdrtas_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdrtas.c:445:8-24: WARNING: wdrtas_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt285.c:104:1-17: WARNING: watchdog_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt977.c:276:8-24: WARNING: wdt977_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt.c:424:8-24: WARNING: wdt_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt.c:484:8-24: WARNING: wdt_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt_pci.c:464:8-24: WARNING: wdtpci_fops: .write() has stream semantic; safe to change nonseekable_open -> stream_open. drivers/watchdog/wdt_pci.c:527:8-24: WARNING: wdtpci_temp_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. net/batman-adv/log.c:105:1-17: WARNING: batadv_log_fops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. sound/core/control.c:57:7-23: WARNING: snd_ctl_f_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. sound/core/rawmidi.c:385:7-23: WARNING: snd_rawmidi_f_ops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. sound/core/seq/seq_clientmgr.c:310:7-23: WARNING: snd_seq_f_ops: .read() and .write() have stream semantic; safe to change nonseekable_open -> stream_open. sound/core/timer.c:1428:7-23: WARNING: snd_timer_f_ops: .read() has stream semantic; safe to change nonseekable_open -> stream_open. One can also recheck/review the patch via generating it with explanation comments included via $ make coccicheck MODE=patch COCCI=scripts/coccinelle/api/stream_open.cocci SPFLAGS="-D explain" (*) This second group also contains cases with read/write deadlocks that stream_open.cocci don't yet detect, but which are still valid to convert to stream_open since ppos is not used. For example drivers/pci/switch/switchtec.c calls wait_for_completion_interruptible() in its .read, but stream_open.cocci currently detects only "wait_event*" as blocking. Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yongzhi Pan <panyongzhi@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Tejun Heo <tj@kernel.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Nikolaus Rath <Nikolaus@rath.org> Cc: Han-Wen Nienhuys <hanwen@google.com> Cc: Anatolij Gustschin <agust@denx.de> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James R. Van Zandt" <jrv@vanzandt.mv.com> Cc: Corey Minyard <minyard@acm.org> Cc: Harald Welte <laforge@gnumonks.org> Acked-by: Lubomir Rintel <lkundrak@v3.sk> [scr24x_cs] Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Johan Hovold <johan@kernel.org> Cc: David Herrmann <dh.herrmann@googlemail.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com> Cc: Jean Delvare <jdelvare@suse.com> Acked-by: Guenter Roeck <linux@roeck-us.net> [watchdog/* hwmon/*] Cc: Rudolf Marek <r.marek@assembler.cz> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Kurt Schwemmer <kurt.schwemmer@microsemi.com> Acked-by: Logan Gunthorpe <logang@deltatee.com> [drivers/pci/switch/switchtec] Acked-by: Bjorn Helgaas <bhelgaas@google.com> [drivers/pci/switch/switchtec] Cc: Benson Leung <bleung@chromium.org> Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> [platform/chrome] Cc: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> [rtc/*] Cc: Mark Brown <broonie@kernel.org> Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Zwane Mwaikambo <zwanem@gmail.com> Cc: Marek Lindner <mareklindner@neomailbox.ch> Cc: Simon Wunderlich <sw@simonwunderlich.de> Cc: Antonio Quartulli <a@unstable.cc> Cc: "David S. Miller" <davem@davemloft.net> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
2019-03-18spi: spidev: Enable control of inter-word delaysJan Kundrát
Commit b7bb367afa4b added support for inserting delays in between individual words within a single SPI transaction. This makes it accessible from userspace. WARNING: This delay is silently ignored unless the SPI controller implements extra support for it. This is similar to how the in-kernel users handle the other existing property, spi_transfer->word_delay. Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-10spi: spidev: Fix OF tree warning logicTrent Piepho
spidev will make a big fuss if a device tree node binds a device by using "spidev" as the node's compatible property. However, the logic for this isn't looking for "spidev" in the compatible, but rather checking that the device is NOT compatible with spidev's list of devices. This causes a false positive if a device not named "rohm,dh2228fv", etc. binds to spidev, even if a means other than putting "spidev" in the device tree was used. E.g., the sysfs driver_override attribute. Signed-off-by: Trent Piepho <tpiepho@impinj.com> Reviewed-by: Jan Kundrát <jan.kundrat@cesnet.cz> Tested-by: Jan Kundrát <jan.kundrat@cesnet.cz> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-08spidev: Enable the Liebherr's BK4 board to work with spidev driverLukasz Majewski
With this commit the DSPI driver on the BK4 board can be used for SPI transmission managed from user space (via /dev/spidev0.0). Example usage/testing: insmod ./spi-fsl-dspi.ko ./spidev_test -D /dev/spidev0.0 -s 3000000 -v -H -b 8 -p "\xCC\x11\x22\x74" Signed-off-by: Lukasz Majewski <lukma@denx.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-08Merge branch 'for-spi' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
Pull spi uaccess delousing from Al Viro: "Getting rid of pointless __get_user() and friends in drivers/spi. [ the only reason it's on a separate branch is that I hoped it would be picked by spi folks; looks like mail asking them to grab it got lost and I hadn't followed up on that ]" * 'for-spi' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: spidev: quit messing with access_ok()
2017-06-29spidev: quit messing with access_ok()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-05-14spi: spidev: use memdup_userGeliang Tang
Use memdup_user() helper instead of open-coding to simplify the code. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-14spi: spidev: remove unused completionSeraphime Kirkovski
This removes an unused completion from spidev_sync. It was introduced in commit 25d5cb4b0375e ("spi: remove some spidev oops-on-rmmod paths") and it was no longer used after: commit 98d6f47958001 ("spi: spidev: use spi_sync instead of spi_async") Signed-off-by: Seraphime Kirkovski (Haapie) <kirkseraph@gmail.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-16spi: spidev: Add sx1301 to device tree compatibility listBen Whitten
Add entry for the semtech sx1301 baseband processor implementing a LoRa concentrator IP. At this time this chip requires an spidev userspace driver. Signed-off-by: Ben Whitten <ben.whitten@lairdtech.com> Signed-off-by: Steve deRosier <derosier@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-21spi: spidev: Add device to spidev device tree compatibility listFabien Lahoudere
Entries are needed in the spidev ID list to configure configure it from a device tree. Add entry for the following device: - "ge,achc" : GE Healthcare USB Management Controller The USB Management Controller does not expose USB to the host, but acts as an offload engine, communicating with specific USB based data acquisition devices which are connected to it, extracting the required data and providing it to the host via other methods. SPI is used as an out-of-band configuration channel. Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.co.uk> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-07-04spi: spidev: Add ACPI probing supportMika Westerberg
Some IoT and maker software stacks are using spidev to perform raw access to the SPI bus instead of relying existing drivers provided by the kernel. They then implement their own "drivers" in userspace on top of the spidev raw interface. This is far from being an ideal solution but we do not want to prevent using mainline Linux in these devices. Now, it turns out that Windows has similar SPI devices than spidev which allow raw access on the SPI bus to userspace programs as described in the link below: https://msdn.microsoft.com/windows/hardware/drivers/spb/spi-tests-in-mitt These SPI test devices are also meant to be used during development and testing. In order to allow usage of spidev for development and testing in Linux, add those same ACPI IDs to the spidev driver (which is Linux counterpart of the Windows SPI test devices), but complain loudly so that users know it is not good idea to use it in production systems. Instead they should be using proper drivers for peripherals connected to the SPI bus. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-11Merge remote-tracking branches 'spi/topic/overlay', 'spi/topic/pxa2xx', ↵Mark Brown
'spi/topic/s3c64xx', 'spi/topic/sh-msiof' and 'spi/topic/spidev' into spi-next
2015-12-16spi: spidev: Hold spi_lock over all defererences of spi in release()Mark Brown
We use the spi_lock spinlock to protect against races between the device being removed and file operations on the spidev. This means that in the removal path all references to the device need to be done under lock as in removal we dropping references to the device. Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-30spi: spidev: Use "%u" to format __u32Geert Uytterhoeven
On 64-bit with CONFIG_SPI_DEBUG=y and #define VERBOSE: drivers/spi/spidev.c:287:3: warning: format '%zd' expects argument of type 'signed size_t', but argument 4 has type '__u32' [-Wformat=] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-04Merge remote-tracking branches 'spi/topic/omap-100k', ↵Mark Brown
'spi/topic/omap-uwire', 'spi/topic/owner', 'spi/topic/pxa' and 'spi/topic/pxa2xx' into spi-next
2015-10-28spi: Drop owner assignment from spi_driversAndrew F. Davis
An spi_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Andrew F. Davis <afd@ti.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-09-22Merge remote-tracking branches 'spi/fix/spidev' and 'spi/fix/xtfpga' into ↵Mark Brown
spi-linus
2015-09-11spi: spidev: fix possible NULL dereferenceSudip Mukherjee
During the last close we are freeing spidev if spidev->spi is NULL, but just before checking if spidev->spi is NULL we are dereferencing it. Lets add a check there to avoid the NULL dereference. Fixes: 9169051617df ("spi: spidev: Don't mangle max_speed_hz in underlying spi device") Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-31Merge remote-tracking branches 'spi/topic/s3c64xx', 'spi/topic/sg', ↵Mark Brown
'spi/topic/sh-msiof', 'spi/topic/spidev' and 'spi/topic/stats' into spi-next
2015-08-04spi: spidev: fix inconsistent indentingColin Ian King
Fix inconsistent indenting in spidev_open, no functional change. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-16spi: spidev: Fix typoFabio Estevam
Fix the typo in "compatible". Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07spi: spidev: add compatible value for LTC2488Jiri Prchal
Since spidev is no more allowed to use in DT and is really loudly warned about it I'd like to add this compatible value. (Geert Uytterhoeven wrote: "Add the compatible value for your device to the spidev_dt_ids[] array in drivers/spi/spidev.c.") Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-18Merge remote-tracking branches 'spi/topic/sirf', 'spi/topic/spidev' and ↵Mark Brown
'spi/topic/zynq' into spi-next
2015-05-11spi: spidev: Remove unneeded variableFabio Estevam
Remove unneeded variable used to store return value. The semantic patch that makes this change is available in scripts/coccinelle/misc/returnvar.cocci. More information about semantic patching is available at http://coccinelle.lip6.fr/ Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-04-23spi: spidev: use spi_sync instead of spi_asyncMartin Sperl
This has the benefit that the "optimization" of the framework in regards to spi_sync will also benefit spidev users directly and allow running spi transfers without a necessary context-switch to message-pump. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-27spi: spidev: Warn loudly if instantiated from DT as "spidev"Mark Brown
Since spidev is a detail of how Linux controls a device rather than a description of the hardware in the system we should never have a node described as "spidev" in DT, any SPI device could be a spidev so this is just not a useful description. In order to help prevent users from writing such device trees generate a warning if spidev is instantiated as a DT node without an ID in the match table. Signed-off-by: Mark Brown <broonie@kernel.org>
2015-03-23spi: spidev: fix possible arithmetic overflow for multi-transfer messageIan Abbott
`spidev_message()` sums the lengths of the individual SPI transfers to determine the overall SPI message length. It restricts the total length, returning an error if too long, but it does not check for arithmetic overflow. For example, if the SPI message consisted of two transfers and the first has a length of 10 and the second has a length of (__u32)(-1), the total length would be seen as 9, even though the second transfer is actually very long. If the second transfer specifies a null `rx_buf` and a non-null `tx_buf`, the `copy_from_user()` could overrun the spidev's pre-allocated tx buffer before it reaches an invalid user memory address. Fix it by checking that neither the total nor the individual transfer lengths exceed the maximum allowed value. Thanks to Dan Carpenter for reporting the potential integer overflow. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-02-24spi: spidev: only use up TX/RX bounce buffer space when neededIan Abbott
This patch changes the way space is reserved in spidev's pre-allocated TX and RX bounce buffers to avoid wasting space in the buffers for an SPI message consisting of multiple, half-duplex transfers in different directions. Background: spidev data structures have separate, pre-allocated TX and RX bounce buffers (`spidev->tx_buffer` and `spidev->rx_buffer`) of fixed size (`bufsiz`). The `SPI_IOC_MESSAGE(N)` ioctl processing uses a kernel copy of the N `struct spi_ioc_transfer` elements copied from the userspace ioctl arg pointer. In these elements: `.len` is the length of transfer in bytes; `.rx_buf` is either a userspace pointer to a buffer to copy the RX data to or is set to 0 to discard the data; and `.tx_buf` is either a userspace pointer to TX data supplied by the user or is set to 0 to transmit zeros for this transfer. `spidev_message()` uses the array of N `struct spi_ioc_transfer` elements to construct a kernel SPI message consisting of a `struct spi_message` containing a linked list (allocated as an array) of N `struct spi_transfer` elements. This involves iterating through the `struct spi_ioc_transfer` and `struct spi_transfer` elements (variables `u_tmp` and `k_tmp` respectively). Before the first iteration, variables `tx_buf` and `rx_buf` point to the start of the TX and RX bounce buffers `spidev->tx_buffer` and `spidev->rx_buffer` and variable `total` is set to 0. These variables keep track of the next available space in the bounce buffers and the total length of the SPI message. Each iteration checks that there is enough room left in the buffers for the transfer. If `u_tmp->rx_buf` is non-zero, `k_tmp->rx_buf` is set to `rx_buf`, otherwise it remains set to NULL. If `u_tmp->tx_buf` is non-zero, `k_tmp->tx_buf` is set to `tx_buf` and the userspace TX data copied there, otherwise it remains set to NULL. The variables `total`, `rx_buf` and `tx_buf` are advanced by the length of the transfer. The "problem": While iterating through the transfers, the local bounce buffer "free space" pointer variables `tx_buf` and `rx_buf` are always advanced by the length of the transfer. If `u_tmp->rx_buf` is 0 (so `k_tmp->rx_buf` is NULL), then `rx_buf` is advanced unnecessarily and that part of `spidev->rx_buffer` is wasted. Similarly, if `u_tmp->tx_buf` is 0 (so `k_tmp->tx_buf` is NULL), part of `spidev->tx_buffer` is wasted. What this patch does: To avoid wasting space unnecessarily in the RX bounce buffer, only advance `rx_buf` by the transfer length if `u_tmp->rx_buf` is non-zero. Similarly, to avoid wasting space unnecessarily in the TX bounce buffer, only advance `tx_buf` if `u_tmp->tx_buf is non-zero. To avoid pointer subtraction, use new variables `rx_total` and `tx_total` to keep track of the amount of space allocated in each of the bounce buffers. If these exceed the available space, a `-EMSGSIZE` error will be returned. Limit the total length of the transfers (tracked by variable `total`) to `INT_MAX` instead of `bufsiz`, returning an `-EMSGSIZE` error if exceeded. The total length is returned by `spidev_message()` on success and we want that to be non-negative. The message size limits for the `SPI_IOC_MESSAGE(N)` ioctl are now as follows: (a) total length of transfers is <= INTMAX; (b) total length of transfers with non-NULL rx_buf is <= bufsiz; (c) total length of transfers with non-NULL tx_buf is <= bufsiz. Some transfers may have NULL rx_buf and NULL tx_buf. If the transfer is completed successfully by the SPI core, `spidev_message()` iterates through the transfers to copy any RX data from the bounce buffer back to userspace on those transfers where `u_tmp->rx_buf` is non-zero. The variable `rx_buf` is again used to keep track of the corresponding positions in the bounce buffer. Now it is only advanced for those transfers that use the RX bounce buffer. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-02-08Merge remote-tracking branches 'spi/topic/sirf', 'spi/topic/spidev', ↵Mark Brown
'spi/topic/st-ssc' and 'spi/topic/ti-qspi' into spi-next
2015-02-02spi: spidev: Convert buf pointers for 32-bit compat SPI_IOC_MESSAGE(n)Ian Abbott
The SPI_IOC_MESSAGE(n) ioctl commands' argument points to an array of n struct spi_ioc_transfer elements. The spidev's compat_ioctl handler just converts this pointer and passes it on to the unlocked_ioctl handler to process it. The tx_buf and rx_buf members of struct spi_ioc_transfer are of type __u64 and hold pointer values. A 32-bit userspace application running in a 64-bit kernel might not have widened the 32-bit pointers correctly for the kernel. The application might have sign-extended the pointer to when the kernel expects it to be zero-extended, or vice versa, leading to an -EFAULT being returned by spidev_message() if the widened pointer is invalid. Handle the SPI_IOC_MESSAGE(n) ioctl commands specially in the compat_ioctl handler, calling new function spidev_compat_ioctl_message() to handle them. This processes them in the same way as the unlocked_ioctl handler except that it uses compat_ptr() to convert the tx_buf and rx_buf members of each struct spi_ioc_transfer element. To save code, factor out part of the unlocked_ioctl handler into a new function spidev_get_ioc_message(). This checks the ioctl command code is a valid SPI_IOC_MESSAGE(n), determines n and copies the array of n struct spi_ioc_transfer elements from userspace into dynamically allocated memory, returning either a pointer to the memory, an ERR_PTR(-err) value, or NULL (for SPI_IOC_MESSAGE(0)). Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-22spi: Remove FSF mailing addressesJarkko Nikula
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>