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2018-05-09i2c: axxia: enable clock before calling clk_get_rate()Tobias Jordan1-12/+14
axxia_i2c_init() uses clk_get_rate() for idev->i2c_clk. clk_get_rate() should only be called if the clock is enabled, so ensure that by moving the clk_prepare_enable() call before the call to axxia_i2c_init(). Found by Linux Driver Verification project (linuxtesting.org). Fixes: 08678b850cd0 ("i2c: axxia: Add I2C driver for AXM55xx") Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: rcar: enhance comment to avoid regressionsWolfram Sang1-0/+2
Give a clear testcase for people wishing to change this code. It is also a reminder for me if people ask about it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: core: ACPI: Log device not acking errors at dbg loglevelHans de Goede1-4/+10
Unfortunately some DSDTs issue bogus i2c reads to non existing devices resulting in -EREMOTEIO errors because the non existing device of course does not ack. This happens e.g. from the The Asus T100TA's _BIX method, the DSDT on the T100TA defines 2 resources on the I2C1 bus: Name (EHID, ResourceTemplate () { I2cSerialBusV2 (0x005B, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , Exclusive, ) }) OperationRegion (EHOR, GenericSerialBus, Zero, 0x0100) Field (EHOR, BufferAcc, NoLock, Preserve) { Connection (EHID), Offset (0x01), AccessAs (BufferAcc, AttribBytes (0x10)), ABCD, 8 } Name (UMPC, ResourceTemplate () { I2cSerialBusV2 (0x0066, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , Exclusive, ) }) The _BIX method does a single read (on each BIX() call) from the EHID device through the ABCD Field, only to completely ignore the result. This read always fails as there is no i2c client at address 0x5b. The _BIX method also does several reads from the UMPC device and actually uses the results of those to provide battery information. IIRC I've also seen some DSTDs which do an i2c read to detect if a device is present, also leading to false positive errors being logged. Esp. the _BIX use is problematic as the _BIX method gets called periodically to monitor battery status. This commit stops the logs from filling up with errors like these: [ 57.327858] i2c i2c-0: i2c read 16 bytes from client@0x5b starting at reg 0x1 failed, error: -121 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: core: ACPI: Improve OpRegion read errorsHans de Goede1-1/+2
When we get an error doing an ACPI SerialBus I2C OpRegion read log some useful details, like the client address and which register is being read. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: mlxcpld: Allow configurable adapter id for mlxcpldMichael Shych1-0/+2
It allows mlxcpld driver to be connected to pre-defined adapter number equal or greater than one, in order to avoid current limitation, assuming usage of id number one only. Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: mlxcpld: Fix adapter functionality support callbackMichael Shych1-1/+8
It fixes report about supported functionality. Functionality can be different up to CPLD capability. Fixes: 6bec23bff9149 (i2c: mlxcpld: add master driver for mellanox systems) Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: mlxcpld: Add support for smbus block read transactionMichael Shych1-6/+32
It adds support for smbus block read transaction. CPLD smbus block read bit of capability register is verified during driver initialization, and driver data is updated if such capability is available. In case an upper layer requests a read transaction of length one and expects that length will be the first received byte, driver will notify CPLD about SMBus block read transaction flavor, so CPLD will know to execute such kind of transaction. Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: mlxcpld: Add support for extended transaction length for i2c-mlxcpldMichael Shych1-2/+17
It adds support for extended length of read and write transactions. New CPLD logic allows double size of the read and write transactions length. This feature is verified through capability register, which is renamed from unclear LPF_REG to CPBLTY_REG. Two bits 5 and 6 of these register are used for length capability detection, while only 01 combination indicates support of extended transaction length. Others mean lack of such support. Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: mediatek: use of_device_get_match_data()Ryder Lee1-6/+2
The usage of of_device_get_match_data() reduce the code size a bit. Also, the only way to call mtk_i2c_probe() is to match an entry in mtk_i2c_of_match[], so of_id cannot be NULL. Signed-off-by: Ryder Lee <ryder.lee@mediatek.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: s3c2410: Remove support for Exynos5440Krzysztof Kozlowski1-2/+0
The Exynos5440 is not actively developed, there are no development boards available and probably there are no real products with it. Remove wide-tree support for Exynos5440. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i801: Don't restore config registers on runtime PMJean Delvare1-2/+1
Restoring configuration registers is only needed when we hand control to the firmware. This is never the case with runtime power management. The device will autosuspend whenever not used, so avoid useless register writes by defining suspend/resume only, and not runtime_suspend/runtime_resume. Signed-off-by: Jean Delvare <jdelvare@suse.de> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: at91: Read all available bytes at onceDavid Engraf1-2/+10
With FIFO enabled it is possible to read multiple bytes at once in the interrupt handler as long as RXRDY is set. This may also reduce the number of interrupts. This patch polls RXRDY and reads all available bytes at once. Signed-off-by: David Engraf <david.engraf@sysgo.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> [wsa: reformatted comment] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i2c-stm32f7: Implement I2C release mechanismPierre-Yves MORDRET1-3/+24
Feature prevents I2C lock-ups. Mechanism resets I2C state machine and releases SCL/SDA signals but preserves I2C registers. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i2c-stm32f7: Add DMA supportPierre-Yves MORDRET2-21/+196
This patch adds DMA support for i2c-stm32f7 driver Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i2c-stm32: Add generic DMA APIPierre-Yves MORDRET2-0/+190
This patch adds a generic DMA API to implement DMA support for i2c-stm32fx drivers Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i2c-stm32f7: Add initial SMBus protocols supportPierre-Yves MORDRET1-9/+368
This patch adds SMBus support for I2C controller embedded in STM32F7 Soc. All SMBus protocols are implemented except SMBus-specific protocols like SMBus Host Notification and SMBus Alert protocols. Implemented: SMBus Quick command, Send byte, Receive byte, Write byte/word, read byte/word, Process call, Block write/read and Block write-block read process call. Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i2c-stm32f7: Add slave supportPierre-Yves MORDRET2-6/+429
This patch adds slave support for I2C controller embedded in STM32F7 SoC Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: i2c-stm32f7: Add 10-bit address supportPierre-Yves MORDRET1-5/+17
This patch adds support for 10-bit device address for STM32F7 I2C Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-27i2c: sprd: Fix the i2c count issueBaolin Wang1-4/+2
We found the I2C controller count register is unreliable sometimes, that will cause I2C to lose data. Thus we can read the data count from 'i2c_dev->count' instead of the I2C controller count register. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-27i2c: sprd: Prevent i2c accesses after suspend is calledBaolin Wang1-0/+16
Add one flag to indicate if the i2c controller has been in suspend state, which can prevent i2c accesses after i2c controller is suspended following system suspend. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-27i2c: dev: prevent ZERO_SIZE_PTR deref in i2cdev_ioctl_rdwr()Alexander Popov1-1/+1
i2cdev_ioctl_rdwr() allocates i2c_msg.buf using memdup_user(), which returns ZERO_SIZE_PTR if i2c_msg.len is zero. Currently i2cdev_ioctl_rdwr() always dereferences the buf pointer in case of I2C_M_RD | I2C_M_RECV_LEN transfer. That causes a kernel oops in case of zero len. Let's check the len against zero before dereferencing buf pointer. This issue was triggered by syzkaller. Signed-off-by: Alexander Popov <alex.popov@linux.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [wsa: use '< 1' instead of '!' for easier readability] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-18i2c: Remove depends on HAS_DMA in case of platform dependencyGeert Uytterhoeven1-3/+0
Remove dependencies on HAS_DMA where a Kconfig symbol depends on another symbol that implies HAS_DMA, and, optionally, on "|| COMPILE_TEST". In most cases this other symbol is an architecture or platform specific symbol, or PCI. Generic symbols and drivers without platform dependencies keep their dependencies on HAS_DMA, to prevent compiling subsystems or drivers that cannot work anyway. This simplifies the dependencies, and allows to improve compile-testing. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-12i2c: add param sanity check to i2c_transfer()Ard Biesheuvel1-0/+3
The API docs describe i2c_transfer() as taking a pointer to an array of i2c_msg containing at least 1 entry, but leaves it to the individual drivers to sanity check the msgs and num parameters. Let's do this in core code instead. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [wsa: changed '<= 0' to '< 1'] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-12i2c: i801: Restore configuration at shutdownJean Delvare1-0/+10
On some systems, the BIOS expects certain SMBus register values to match the hardware defaults. Restore these configuration registers at shutdown time to avoid confusing the BIOS. This avoids hard-locking such systems upon reboot. Signed-off-by: Jean Delvare <jdelvare@suse.de> Tested-by: Jason Andryuk <jandryuk@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@vger.kernel.org
2018-04-12i2c: i801: Save register SMBSLVCMD value only onceJean Delvare1-2/+4
Saving the original value of register SMBSLVCMD in i801_enable_host_notify() doesn't work, because this function is called not only at probe time but also at resume time. Do it in i801_probe() instead, so that the saved value is not overwritten at resume time. Signed-off-by: Jean Delvare <jdelvare@suse.de> Fixes: 22e94bd6779e ("i2c: i801: store and restore the SLVCMD register at load and unload") Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Tested-by: Jason Andryuk <jandryuk@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@vger.kernel.org # v4.10+
2018-04-07Merge branch 'i2c/for-4.17' of ↵Linus Torvalds20-760/+1880
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: -I2C core now reports proper OF style module alias. I'd like to repeat the note from the commit msg here (Thanks, Javier!): NOTE: This patch may break out-of-tree drivers that were relying on this behavior, and only had an I2C device ID table even when the device was registered via OF. There are no remaining drivers in mainline that do this, but out-of-tree drivers have to be fixed and define a proper OF device ID table to have module auto-loading working. - new driver for the SynQuacer I2C controller - major refactoring of the QUP driver - the piix4 driver now uses request_muxed_region which should fix a long standing resource conflict with the sp5100_tco watchdog - a bunch of small core & driver improvements * 'i2c/for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (53 commits) i2c: add support for Socionext SynQuacer I2C controller dt-bindings: i2c: add binding for Socionext SynQuacer I2C i2c: Update i2c_trace_msg static key to modern api i2c: fix parameter of trace_i2c_result i2c: imx: avoid taking clk_prepare mutex in PM callbacks i2c: imx: use clk notifier for rate changes i2c: make i2c_check_addr_validity() static i2c: rcar: fix mask value of prohibited bit dt-bindings: i2c: document R8A77965 bindings i2c: pca-platform: drop gpio from platform data i2c: pca-platform: use device_property_read_u32 i2c: pca-platform: unconditionally use devm_gpiod_get_optional sh: sh7785lcr: add GPIO lookup table for i2c controller reset i2c: qup: reorganization of driver code to remove polling for qup v2 i2c: qup: reorganization of driver code to remove polling for qup v1 i2c: qup: send NACK for last read sub transfers i2c: qup: fix buffer overflow for multiple msg of maximum xfer len i2c: qup: change completion timeout according to transfer length i2c: qup: use the complete transfer length to choose DMA mode i2c: qup: proper error handling for i2c error in BAM mode ...
2018-04-04i2c: add support for Socionext SynQuacer I2C controllerArd Biesheuvel3-0/+678
This is a cleaned up version of the I2C controller driver for the Fujitsu F_I2C IP, which was never supported upstream, and has now been incorporated into the Socionext SynQuacer SoC. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> [wsa: updated MAINTAINERS entry and removed two empty lines] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03i2c: Update i2c_trace_msg static key to modern apiDavidlohr Bueso1-6/+7
No changes in refcount semantics -- key init is false; replace static_key_slow_inc|dec with static_branch_inc|dec static_key_false with static_branch_unlikely Added a '_key' suffix to i2c_trace_msg, for better self documentation. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03i2c: fix parameter of trace_i2c_resultAhbong Chang1-1/+1
According to the event i2c_result defined in include/trace/events/i2c.h, the second parameter should be the number of messages instead of the ended loop index. The value of ended loop index is the same as ret. Signed-off-by: Ahbong Chang <cwahbong@google.com> Reviewed-by: Todd Poynor <toddpoynor@google.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03i2c: imx: avoid taking clk_prepare mutex in PM callbacksLucas Stach1-2/+2
This is unsafe, as the runtime PM callbacks are called from the PM workqueue, so this may deadlock when handling an i2c attached clock, which may already hold the clk_prepare mutex from another context. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03i2c: imx: use clk notifier for rate changesLucas Stach1-7/+25
Instead of repeatedly calling clk_get_rate for each transfer, register a clock notifier to update the cached divider value each time the clock rate actually changes. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03Merge tag 'arch-removal' of ↵Linus Torvalds3-757/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pul removal of obsolete architecture ports from Arnd Bergmann: "This removes the entire architecture code for blackfin, cris, frv, m32r, metag, mn10300, score, and tile, including the associated device drivers. I have been working with the (former) maintainers for each one to ensure that my interpretation was right and the code is definitely unused in mainline kernels. Many had fond memories of working on the respective ports to start with and getting them included in upstream, but also saw no point in keeping the port alive without any users. In the end, it seems that while the eight architectures are extremely different, they all suffered the same fate: There was one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem, which was more costly than licensing newer off-the-shelf CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems that all the SoC product lines are still around, but have not used the custom CPU architectures for several years at this point. In contrast, CPU instruction sets that remain popular and have actively maintained kernel ports tend to all be used across multiple licensees. [ See the new nds32 port merged in the previous commit for the next generation of "one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem" - Linus ] The removal came out of a discussion that is now documented at https://lwn.net/Articles/748074/. Unlike the original plans, I'm not marking any ports as deprecated but remove them all at once after I made sure that they are all unused. Some architectures (notably tile, mn10300, and blackfin) are still being shipped in products with old kernels, but those products will never be updated to newer kernel releases. After this series, we still have a few architectures without mainline gcc support: - unicore32 and hexagon both have very outdated gcc releases, but the maintainers promised to work on providing something newer. At least in case of hexagon, this will only be llvm, not gcc. - openrisc, risc-v and nds32 are still in the process of finishing their support or getting it added to mainline gcc in the first place. They all have patched gcc-7.3 ports that work to some degree, but complete upstream support won't happen before gcc-8.1. Csky posted their first kernel patch set last week, their situation will be similar [ Palmer Dabbelt points out that RISC-V support is in mainline gcc since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]" This really says it all: 2498 files changed, 95 insertions(+), 467668 deletions(-) * tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits) MAINTAINERS: UNICORE32: Change email account staging: iio: remove iio-trig-bfin-timer driver tty: hvc: remove tile driver tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers serial: remove tile uart driver serial: remove m32r_sio driver serial: remove blackfin drivers serial: remove cris/etrax uart drivers usb: Remove Blackfin references in USB support usb: isp1362: remove blackfin arch glue usb: musb: remove blackfin port usb: host: remove tilegx platform glue pwm: remove pwm-bfin driver i2c: remove bfin-twi driver spi: remove blackfin related host drivers watchdog: remove bfin_wdt driver can: remove bfin_can driver mmc: remove bfin_sdh driver input: misc: remove blackfin rotary driver input: keyboard: remove bf54x driver ...
2018-03-26i2c: remove bfin-twi driverArnd Bergmann3-756/+0
The blackfin architecture is getting removed, so the twi driver can also be removed. Acked-by: Aaron Wu <aaron.wu@analog.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-24i2c: make i2c_check_addr_validity() staticWolfram Sang2-2/+1
After previous refactoring, there is only one user in the same file left. Make the function static now. [wsa: added 'int' to bare 'unsigned'] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: rcar: fix mask value of prohibited bitHiromitsu Yamasaki1-2/+2
According to documentation, Bit 7 of ICMSR is unused and 0 should be written to it. Fix the mask accordingly. Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com> [wsa: edited commit message] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24Merge tag 'at24-4.17-updates-for-wolfram' of ↵Wolfram Sang2-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into i2c/for-4.17 "three new special cases for device tree compatible strings"
2018-03-24i2c: i2c-stm32f7: fix no check on returned setupPierre-Yves MORDRET1-0/+5
Before assigning returned setup structure check if not null Fixes: 463a9215f3ca7600b5ff ("i2c: stm32f7: fix setup structure") Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Acked-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2018-03-24i2c: pca-platform: use device_property_read_u32Chris Packham1-7/+6
Use device_property_read_u32 instead of of_property_read_u32_index to lookup the "clock-frequency" property. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: pca-platform: unconditionally use devm_gpiod_get_optionalChris Packham1-17/+4
Allow for the reset-gpios property to be defined in the device tree or via a GPIO lookup table. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: reorganization of driver code to remove polling for qup v2Abhishek Sahu1-385/+515
Following are the major issues in current driver code 1. The current driver simply assumes the transfer completion whenever its gets any non-error interrupts and then simply do the polling of available/free bytes in FIFO. 2. The block mode is not working properly since no handling in being done for OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_READ. 3. An i2c transfer can contain multiple message and QUP v2 supports reconfiguration during run in which the mode should be same for all the sub transfer. Currently the mode is being programmed before every sub transfer which is functionally wrong. If one message is less than FIFO length and other message is greater than FIFO length, then transfers will fail. Because of above, i2c v2 transfers of size greater than 64 are failing with following error message i2c_qup 78b6000.i2c: timeout for fifo out full To make block mode working properly and move to use the interrupts instead of polling, major code reorganization is required. Following are the major changes done in this patch 1. Remove the polling of TX FIFO free space and RX FIFO available bytes and move to interrupts completely. QUP has QUP_MX_OUTPUT_DONE, QUP_MX_INPUT_DONE, OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_REQ interrupts to handle FIFO’s properly so check all these interrupts. 2. Determine the mode for transfer before starting by checking all the tx/rx data length in each message. The complete message can be transferred either in DMA mode or Programmed IO by FIFO/Block mode. in DMA mode, both tx and rx uses same mode but in PIO mode, the TX and RX can be in different mode. 3. During write, For FIFO mode, TX FIFO can be directly written without checking for FIFO space. For block mode, the QUP will generate OUT_BLOCK_WRITE_REQ interrupt whenever it has block size of available space. 4. During read, both TX and RX FIFO will be used. TX will be used for writing tags and RX will be used for receiving the data. In QUP, TX and RX can operate in separate mode so configure modes accordingly. 5. For read FIFO mode, wait for QUP_MX_INPUT_DONE interrupt which will be generated after all the bytes have been copied in RX FIFO. For read Block mode, QUP will generate IN_BLOCK_READ_REQ interrupts whenever it has block size of available data. 6. Split the transfer in chunk of one QUP block size(256 bytes) and schedule each block separately. QUP v2 supports reconfiguration during run in which QUP can transfer multiple blocks without issuing a stop events. 7. Port the SMBus block read support for new code changes. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Sricharan R <sricharan@codeaurora.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: reorganization of driver code to remove polling for qup v1Abhishek Sahu1-143/+223
Following are the major issues in current driver code 1. The current driver simply assumes the transfer completion whenever its gets any non-error interrupts and then simply do the polling of available/free bytes in FIFO. 2. The block mode is not working properly since no handling in being done for OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_REQ. Because of above, i2c v1 transfers of size greater than 32 are failing with following error message i2c_qup 78b6000.i2c: timeout for fifo out full To make block mode working properly and move to use the interrupts instead of polling, major code reorganization is required. Following are the major changes done in this patch 1. Remove the polling of TX FIFO free space and RX FIFO available bytes and move to interrupts completely. QUP has QUP_MX_OUTPUT_DONE, QUP_MX_INPUT_DONE, OUT_BLOCK_WRITE_REQ and IN_BLOCK_READ_REQ interrupts to handle FIFO’s properly so check all these interrupts. 2. During write, For FIFO mode, TX FIFO can be directly written without checking for FIFO space. For block mode, the QUP will generate OUT_BLOCK_WRITE_REQ interrupt whenever it has block size of available space. 3. During read, both TX and RX FIFO will be used. TX will be used for writing tags and RX will be used for receiving the data. In QUP, TX and RX can operate in separate mode so configure modes accordingly. 4. For read FIFO mode, wait for QUP_MX_INPUT_DONE interrupt which will be generated after all the bytes have been copied in RX FIFO. For read Block mode, QUP will generate IN_BLOCK_READ_REQ interrupts whenever it has block size of available data. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Sricharan R <sricharan@codeaurora.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: send NACK for last read sub transfersAbhishek Sahu1-1/+4
According to I2c specification, “If a master-receiver sends a repeated START condition, it sends a not-acknowledge (A) just before the repeated START condition”. QUP v2 supports sending of NACK without stop with QUP_TAG_V2_DATARD_NACK so added the same. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Austin Christ <austinwc@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: fix buffer overflow for multiple msg of maximum xfer lenAbhishek Sahu1-84/+110
The BAM mode requires buffer for start tag data and tx, rx SG list. Currently, this is being taken for maximum transfer length (65K). But an I2C transfer can have multiple messages and each message can be of this maximum length so the buffer overflow will happen in this case. Since increasing buffer length won’t be feasible since an I2C transfer can contain any number of messages so this patch does following changes to make i2c transfers working for multiple messages case. 1. Calculate the required buffers for 2 maximum length messages (65K * 2). 2. Split the descriptor formation and descriptor scheduling. The idea is to fit as many messages in one DMA transfers for 65K threshold value (max_xfer_sg_len). Whenever the sg_cnt is crossing this, then schedule the BAM transfer and subsequent transfer will again start from zero. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: change completion timeout according to transfer lengthAbhishek Sahu1-3/+10
Currently the completion timeout is being taken according to maximum transfer length which is too high if SCL is operating in high frequency. This patch calculates timeout on the basis of one-byte transfer time and uses the same for completion timeout. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: use the complete transfer length to choose DMA modeAbhishek Sahu1-6/+7
Currently each message length in complete transfer is being checked for determining DMA mode and if any of the message length is less than FIFO length then non DMA mode is being used which will increase overhead. DMA can be used for any length and it should be determined with complete transfer length. Now, this patch selects DMA mode if the total length is greater than FIFO length. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Austin Christ <austinwc@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: proper error handling for i2c error in BAM modeAbhishek Sahu1-9/+16
Currently the i2c error handling in BAM mode is not working properly in stress condition. 1. After an error, the FIFO are being written with FLUSH and EOT tags which should not be required since already these tags have been written in BAM descriptor itself. 2. QUP state is being moved to RESET in IRQ handler in case of error. When QUP HW encounters an error in BAM mode then it moves the QUP STATE to PAUSE state. In this case, I2C_FLUSH command needs to be executed while moving to RUN_STATE by writing to the QUP_STATE register with the I2C_FLUSH bit set to 1. 3. In Error case, sometimes, QUP generates more than one interrupt which will trigger the complete again. After an error, the flush operation will be scheduled after doing reinit_completion which should be triggered by BAM IRQ callback. If the second QUP IRQ comes during this time then it will call the complete and the transfer function will assume the all the BAM HW descriptors have been completed. 4. The release DMA is being called after each error which will free the DMA tx and rx channels. The error like NACK is very common in I2C transfer and every time this will be overhead. Now, since the error handling is proper so this release channel can be completely avoided. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Sricharan R <sricharan@codeaurora.org> Reviewed-by: Austin Christ <austinwc@codeaurora.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: fix the transfer length for BAM RX EOT FLUSH tagsAbhishek Sahu1-2/+2
In case of FLUSH operation, BAM copies INPUT EOT FLUSH (0x94) instead of normal EOT (0x93) tag in input data stream when an input EOT tag is received during flush operation. So only one tag will be written instead of 2 separate tags. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: schedule EOT and FLUSH tags at the end of transferAbhishek Sahu1-15/+24
The role of FLUSH and EOT tag is to flush already scheduled descriptors in BAM HW in case of error. EOT is required only when descriptors are scheduled in RX FIFO. If all the messages are WRITE, then only FLUSH tag will be used. A single BAM transfer can have multiple read and write messages. The EOT and FLUSH tags should be scheduled at the end of BAM HW descriptors. Since the READ and WRITE can be present in any order so for some of the cases, these tags are not being written correctly. Following is one of the example READ, READ, READ, READ Currently EOT and FLUSH tags are being written after each READ. If QUP gets NACK for first READ itself, then flush will be triggered. It will look for first FLUSH tag in TX FIFO and will stop there so only descriptors for first READ descriptors be flushed. All the scheduled descriptors should be cleared to generate BAM DMA completion. Now this patch is scheduling FLUSH and EOT only once after all the descriptors. So, flush will clear all the scheduled descriptors and BAM will generate the completion interrupt. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Sricharan R <sricharan@codeaurora.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: remove redundant variables for BAM SG countAbhishek Sahu1-24/+18
The rx_nents and tx_nents are redundant. rx_buf and tx_buf can be used for total number of SG entries. Since rx_buf and tx_buf give the impression that it is buffer instead of count so rename it to tx_cnt and rx_cnt for giving it more meaningful variable name. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Austin Christ <austinwc@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: qup: minor code reorganization for use_dmaAbhishek Sahu1-8/+11
1. Assigns use_dma in qup_dev structure itself which will help in subsequent patches to determine the mode in IRQ handler. 2. Does minor code reorganization for loops to reduce the unnecessary comparison and assignment. Signed-off-by: Abhishek Sahu <absahu@codeaurora.org> Reviewed-by: Austin Christ <austinwc@codeaurora.org> Reviewed-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>