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path: root/drivers/i2c/busses/i2c-designware-core.h
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2023-07-02Merge tag 'i2c-for-6.5-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: - I2C has now a co-maintainer taking care of the host drivers. Welcome Andi Shyti and have fun! - platform remove callback converted to return void in drivers - simplify drivers by using devm_clk_get_enabled() - introduce i2c_get_match_data() to avoid more boilerplate code (especially since the core stopped delivering an i2c_device_id) - and the usual bunch of driver updates * tag 'i2c-for-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits) i2c: uniphier: Use devm_clk_get_enabled() i2c: uniphier-f: Use devm_clk_get_enabled() i2c: owl: Use devm_clk_get_enabled() i2c: lpc2k: Use devm_clk_get_enabled() i2c: hix5hd2: Use devm_clk_get_enabled() i2c: sun6i-p2wi: Use devm_clk_get_enabled() i2c: pasemi-platform: Use devm_clk_get_enabled() i2c: mt7621: Use devm_clk_get_enabled() i2c: xiic: Use devm_clk_get_enabled() i2c: davinci: Use platform table macro over module_alias i2c: ocores: use devm_ managed clks i2c: nomadik: Use dev_err_probe() whenever possible i2c: nomadik: Use devm_clk_get_enabled() i2c: nomadik: Remove unnecessary goto label usb: typec: ucsi: Mark dGPUs as DEVICE scope i2c: wmt: Use devm_platform_get_and_ioremap_resource() i2c: versatile: Use devm_platform_get_and_ioremap_resource() i2c: hix5hd2: Add I2C_M_STOP flag support for i2c-hix5hd2 driver. i2c: mpc: Use of_property_read_reg() to parse "reg" i2c: imx-lpi2c: Don't open-code DIV_ROUND_UP ...
2023-06-05i2c: designware: fix idx_write_cnt in read loopDavid Zheng
With IC_INTR_RX_FULL slave interrupt handler reads data in a loop until RX FIFO is empty. When testing with the slave-eeprom, each transaction has 2 bytes for address/index and 1 byte for value, the address byte can be written as data byte due to dropping STOP condition. In the test below, the master continuously writes to the slave, first 2 bytes are index, 3rd byte is value and follow by a STOP condition. i2c_write: i2c-3 #0 a=04b f=0000 l=3 [00-D1-D1] i2c_write: i2c-3 #0 a=04b f=0000 l=3 [00-D2-D2] i2c_write: i2c-3 #0 a=04b f=0000 l=3 [00-D3-D3] Upon receiving STOP condition slave eeprom would reset `idx_write_cnt` so next 2 bytes can be treated as buffer index for upcoming transaction. Supposedly the slave eeprom buffer would be written as EEPROM[0x00D1] = 0xD1 EEPROM[0x00D2] = 0xD2 EEPROM[0x00D3] = 0xD3 When CPU load is high the slave irq handler may not read fast enough, the interrupt status can be seen as 0x204 with both DW_IC_INTR_STOP_DET (0x200) and DW_IC_INTR_RX_FULL (0x4) bits. The slave device may see the transactions below. 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1594 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1594 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1594 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1794 : INTR_STAT=0x204 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x1790 : INTR_STAT=0x200 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1594 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1594 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x1594 : INTR_STAT=0x4 After `D1` is received, read loop continues to read `00` which is the first bype of next index. Since STOP condition is ignored by the loop, eeprom buffer index increased to `D2` and `00` is written as value. So the slave eeprom buffer becomes EEPROM[0x00D1] = 0xD1 EEPROM[0x00D2] = 0x00 EEPROM[0x00D3] = 0xD3 The fix is to use `FIRST_DATA_BYTE` (bit 11) in `IC_DATA_CMD` to split the transactions. The first index byte in this case would have bit 11 set. Check this indication to inject I2C_SLAVE_WRITE_REQUESTED event which will reset `idx_write_cnt` in slave eeprom. Signed-off-by: David Zheng <david.zheng@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-06-05i2c: designware: Add driver support for Wangxun 10Gb NICJiawen Wu
Wangxun 10Gb ethernet chip is connected to Designware I2C, to communicate with SFP. Introduce the property "wx,i2c-snps-model" to match device data for Wangxun in software node case. Since IO resource was mapped on the ethernet driver, add a model quirk to get regmap from parent device. The exists IP limitations are dealt as workarounds: - IP does not support interrupt mode, it works on polling mode. - Additionally set FIFO depth address the chip issue. Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com> Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-04-20i2c: designware: Use PCI PSP driver for communicationMario Limonciello
Currently the PSP semaphore communication base address is discovered by using an MSR that is not architecturally guaranteed for future platforms. Also the mailbox that is utilized for communication with the PSP may have other consumers in the kernel, so it's better to make all communication go through a single driver. Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Mark Hasemeyer <markhas@chromium.org> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Mark Hasemeyer <markhas@chromium.org> Acked-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-01-28i2c: designware: Change from u32 to unsigned int for regmap_read() callsShyam Sundar S K
regmap_read() API signature expects the caller to send "unsigned int" type to return back the read value, but there are some occurrences of 'u32' across i2c-designware-* files. Change them to match the regmap_read() signature. Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-01-28i2c: designware: add a new bit check for IC_CON controlShyam Sundar S K
On some AMD platforms, based on the new designware datasheet, BIOS sets the BIT(11) within the IC_CON register to advertise the "bus clear feature capability". AMD/Designware datasheet says: Bit(11) BUS_CLEAR_FEATURE_CTRL. Read-write,Volatile. Reset: 0. Description: In Master mode: - 1'b1: Bus Clear Feature is enabled. - 1'b0: Bus Clear Feature is Disabled. In Slave mode, this register bit is not applicable. On AMD platform designs: 1. BIOS programs the BUS_CLEAR_FEATURE_CTRL and enables the detection of SCL/SDA stuck low. 2. Whenever the stuck low is detected, the SMU FW shall do the bus recovery procedure. Currently, the way in which the "master_cfg" is built in the driver, it overrides the BUS_CLEAR_FEATURE_CTRL advertised by BIOS and the SMU FW cannot initiate the bus recovery if the stuck low is detected. Hence add a check in i2c_dw_probe_master() that if the BIOS advertises the bus clear feature, let driver not ignore it and adapt accordingly. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-01-09i2c: designware: fix i2c_dw_clk_rate() return size to be u32Hanna Hawa
Make i2c_dw_clk_rate() to return u32 instead of unsigned long, as the function return the value of get_clk_rate_khz() which returns u32. Fixes: b33af11de236 ("i2c: designware: Do not require clock when SSCN and FFCN are provided") Signed-off-by: Hanna Hawa <hhhawa@amazon.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-11-12i2c: designware: Add comment to custom register value constantsJarkko Nikula
DW_IC_COMP_VERSION register contains the ASCII representation of the Synopsys component version. Here 0x3131312A == "111*" means version 1.11* required for DW_IC_SDA_HOLD register availability where '*' means any letter starting from 'a'. DW_IC_COMP_TYPE is constant and is derived from two ASCII letters "DW" followed by a 16-bit unsigned number. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-11-12i2c: designware: Align defines in i2c-designware-core.hJarkko Nikula
Align all defines to the same column. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-11-12i2c: designware: Remove common i2c_dw_disable_int()Jarkko Nikula
Commit 90312351fd1e ("i2c: designware: MASTER mode as separated driver") introduced disable_int pointer but there is no real use for it. Both i2c-designware-master.c and i2c-designware-slave.c set it to the same i2c_dw_disable_int() and scope is inside the same kernel module. Since i2c_dw_disable_int() is just masking interrupts and the direct DW_IC_INTR_MASK register write looks more clear in the code use that and remove it from common code. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-11-12i2c: designware: Define software status flags with BIT()Jarkko Nikula
Define software status flags with a BIT() macro. While at it remove STATUS_IDLE and replace its use with zero initialization and status flags clearing with a mask. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-11-12i2c: designware: Empty receive FIFO in slave interrupt handlerJarkko Nikula
Writes from I2C bus often fail when testing the i2c-designware-slave.c with the slave-eeprom backend. The same writes work correctly when testing with a real 24c02 EEPROM chip. In the tests below an i2c-designware-slave.c instance with the slave-eeprom backend is configured to act as a simulated 24c02 at address 0x65 on an I2C host bus 6. 1. i2cset -y 6 0x65 0x00 0x55 Single byte 0x55 write into address 0x00. No data goes into simulated EEPROM. Debug prints from the i2c_dw_irq_handler_slave(): 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x714 : INTR_STAT=0x204 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 2. i2ctransfer -y 6 w9@0x65 0x00 0xff- Write 8 bytes with decrementing value starting from 0xff at address 0x00 and forward. Only some of the data goes into arbitrary addresses. Content is something like below but varies: 00000000 f9 f8 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 00000050 00 00 00 00 00 00 ff fe 00 00 00 00 00 00 00 00 |................| 000000f0 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fb fa |................| In this case debug prints were: 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x714 : INTR_STAT=0x204 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x510 : INTR_STAT=0x0 Both cases show there is more data coming from the receive FIFO still after detecting the STOP condition. This can be seen from interrupt status bits DW_IC_INTR_STOP_DET (0x200) and DW_IC_INTR_RX_FULL (0x4). Perhaps due interrupt latencies the receive FIFO is not read fast enough, STOP detection happens synchronously when it occurs on the I2C bus and the DW_IC_INTR_RX_FULL keeps coming as long as there are more bytes in the receive FIFO. Fix this by reading the receive FIFO completely empty whenever DW_IC_INTR_RX_FULL occurs. Use RFNE, Receive FIFO Not Empty bit in the DW_IC_STATUS register to loop through bytes in the FIFO. While at it do not test the return code from i2c_slave_event() for the I2C_SLAVE_WRITE_RECEIVED since to my understanding this hardware cannot generate NACK to incoming bytes and debug print itself does not have much value. Reported-by: Tian Ye <tianye@sugon.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-11-12i2c: designware: Fix slave state machine for sequential readsJarkko Nikula
Some read types from I2C bus don't work correctly when testing the i2c-designware-slave.c with the slave-eeprom backend. The same reads work correctly when testing with a real 24c02 EEPROM chip. In the following tests an i2c-designware-slave.c instance with the slave-eeprom backend is configured to act as a simulated 24c02 at address 0x65 on an I2C host bus 6: 1. i2cdump -y 6 0x65 b (OK) Random read. Each byte are read using a byte address write with a current address read in a same message. 2. i2cdump -y 6 0x65 c (OK, was NOK before commit 3b5f7f10ff6e when it was repeating the 1st byte) Repeated current address read. One byte address write message followed by repeated current address read messages. 3. i2cdump -y 6 0x65 i (NOK, each 32 byte block repeats the 1st byte of block) Sequential read using SMBus Block Read. For each 32 byte block a byte address write followed by 32 sequental reads in a same message. These findings are explained because the implementation has had a mismatch between hardware interrupts and what I2C slave events should be sent after those interrupts. Despite that the case 1 happened to have always the I2C slave events sent to a right order with a right data between backend and the I2C bus. Hardware generates the DW_IC_INTR_RD_REQ interrupt when another host is attempting to read and for sequential reads after. DW_IC_INTR_RX_DONE occurs when host does not acknowledge a transmitted byte which is an indication the end of transmission. Those interrupts do not match directly with I2C_SLAVE_READ_REQUESTED and I2C_SLAVE_READ_PROCESSED events which is how the code was and is practically using them. The slave-eeprom backend increases the buffer index with the I2C_SLAVE_READ_PROCESSED event and returns the data from current index when receiving only the I2C_SLAVE_READ_REQUESTED event. That explains the repeated bytes in case 3 and also case 2 before commit 3b5f7f10ff6e ("i2c: designware: slave should do WRITE_REQUESTED before WRITE_RECEIVED"). Patch fixes the case 3 while keep cases 1 and 2 working with following changes: - First DW_IC_INTR_RD_REQ interrupt will change the state machine to read in progress state, send I2C_SLAVE_READ_REQUESTED event and transmit the first byte from backend - Subsequent DW_IC_INTR_RD_REQ interrupts will send I2C_SLAVE_READ_PROCESSED events and transmit next bytes from backend - STOP won't change the state machine. Otherwise case 2 won't work since we cannot distinguish current address read from sequentiel read - DW_IC_INTR_RX_DONE interrupt is needless since there is no mechanism to inform it to a backend. It cannot be used to change state machine at the end of read either due the same reason than above - Next host write to us will change the state machine from read to write in progress state - STATUS_WRITE_IN_PROGRESS and STATUS_READ_IN_PROGRESS are considered now to be status flags not the state of the driver. This is how we treat them in i2c-designware-master.c While at it do not test the return code from i2c_slave_event() for I2C_SLAVE_READ_REQUESTED and I2C_SLAVE_READ_PROCESSED since it returns always 0. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-10-05i2c: designware: Fix handling of real but unexpected device interruptsJarkko Nikula
Commit c7b79a752871 ("mfd: intel-lpss: Add Intel Alder Lake PCH-S PCI IDs") caused a regression on certain Gigabyte motherboards for Intel Alder Lake-S where system crashes to NULL pointer dereference in i2c_dw_xfer_msg() when system resumes from S3 sleep state ("deep"). I was able to debug the issue on Gigabyte Z690 AORUS ELITE and made following notes: - Issue happens when resuming from S3 but not when resuming from "s2idle" - PCI device 00:15.0 == i2c_designware.0 is already in D0 state when system enters into pci_pm_resume_noirq() while all other i2c_designware PCI devices are in D3. Devices were runtime suspended and in D3 prior entering into suspend - Interrupt comes after pci_pm_resume_noirq() when device interrupts are re-enabled - According to register dump the interrupt really comes from the i2c_designware.0. Controller is enabled, I2C target address register points to a one detectable I2C device address 0x60 and the DW_IC_RAW_INTR_STAT register START_DET, STOP_DET, ACTIVITY and TX_EMPTY bits are set indicating completed I2C transaction. My guess is that the firmware uses this controller to communicate with an on-board I2C device during resume but does not disable the controller before giving control to an operating system. I was told the UEFI update fixes this but never the less it revealed the driver is not ready to handle TX_EMPTY (or RX_FULL) interrupt when device is supposed to be idle and state variables are not set (especially the dev->msgs pointer which may point to NULL or stale old data). Introduce a new software status flag STATUS_ACTIVE indicating when the controller is active in driver point of view. Now treat all interrupts that occur when is not set as unexpected and mask all interrupts from the controller. Fixes: c7b79a752871 ("mfd: intel-lpss: Add Intel Alder Lake PCH-S PCI IDs") Reported-by: Samuel Clark <slc2015@gmail.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=215907 Cc: stable@vger.kernel.org # v5.12+ Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-03-01i2c: designware: Use the i2c_mark_adapter_suspended/resumed() helpersHans de Goede
Use the i2c_mark_adapter_suspended/resumed() i2c-core helpers and rely on the i2c-core's suspended checking instead of using DIY code. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-02-11i2c: designware: Add AMD PSP I2C bus supportJan Dabros
Implement an I2C controller sharing mechanism between the host (kernel) and PSP co-processor on some platforms equipped with AMD Cezanne SoC. On these platforms we need to implement "software" i2c arbitration. Default arbitration owner is PSP and kernel asks for acquire as well as inform about release of the i2c bus via mailbox mechanism. +---------+ <- ACQUIRE | | +---------| CPU |\ | | | \ +----------+ SDA | +---------+ \ | |------- MAILBOX +--> | I2C-DW | SCL | +---------+ | |------- | | | +----------+ +---------| PSP | <- ACK | | +---------+ +---------+ <- RELEASE | | +---------| CPU | | | | +----------+ SDA | +---------+ | |------- MAILBOX +--> | I2C-DW | SCL | +---------+ / | |------- | | | / +----------+ +---------| PSP |/ <- ACK | | +---------+ The solution is similar to i2c-designware-baytrail.c implementation, where we are using a generic i2c-designware-* driver with a small "wrapper". In contrary to baytrail semaphore implementation, beside internal acquire_lock() and release_lock() methods we are also applying quirks to lock_bus() and unlock_bus() global adapter methods. With this in place all i2c clients drivers may lock i2c bus for a desired number of i2c transactions (e.g. write-wait-read) without being aware of that such bus is shared with another entity. Modify i2c_dw_probe_lock_support() to select correct semaphore implementation at runtime, since now we have more than one available. Configure new matching ACPI ID "AMDI0019" and register ARBITRATION_SEMAPHORE flag in order to distinguish setup with PSP arbitration. Add myself as a reviewer for I2C DesignWare in order to help with reviewing and testing possible changes touching new i2c-designware-amdpsp.c module. Signed-off-by: Jan Dabros <jsd@semihalf.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> [wsa: removed unneeded blank line and curly braces] Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-11-29i2c: designware: Fix the kernel doc description for struct dw_i2c_devAndy Shevchenko
$ scripts/kernel-doc -none drivers/i2c/busses/i2c-designware-core.h warning: Function parameter or member 'rst' not described in 'dw_i2c_dev' warning: Function parameter or member 'get_clk_rate_khz' not described in 'dw_i2c_dev' warning: Function parameter or member 'flags' not described in 'dw_i2c_dev' warning: Function parameter or member 'functionality' not described in 'dw_i2c_dev' warning: Function parameter or member 'master_cfg' not described in 'dw_i2c_dev' warning: Function parameter or member 'set_sda_hold_time' not described in 'dw_i2c_dev' warning: Function parameter or member 'rinfo' not described in 'dw_i2c_dev' Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Randy Dunlap <rdunla@infradead.org> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-08-11i2c: designware: Fix indentation in the headerAndy Shevchenko
In couple of places the indentation makes harder to read the code. Fix it to be sane. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-04-05i2c: designware: Add driver support for AMD NAVI GPUSanket Goswami
The Latest AMD NAVI GPU card has an integrated Type-C controller and Designware I2C with PCI Interface. The PD controller for USB Type-C can be accessed over I2C. The client driver is part of the USB Type-C UCSI driver. Also, there exists a couple of notable IP limitations that are dealt as workarounds: - I2C transaction work on a polling mode as IP does not generate interrupt. - I2C read command sent twice to address the IP issues. - AMD NAVI GPU based products are already in the commercial market, hence some of the I2C parameters are statically programmed as they can not be part of the ACPI table. Reviewed-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> Co-developed-by: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com> Signed-off-by: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com> Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-02-26i2c: designware: Get right data lengthLiguang Zhang
IC_DATA_CMD[11] indicates the first data byte received after the address phase for receive transfer in Master receiver or Slave receiver mode, this bit was set in some transfer flow. IC_DATA_CMD[7:0] contains the data to be transmitted or received on the I2C bus, so we should use the lower 8 bits to get the real data length. Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-12-09i2c: designware: Make register offsets all of the same widthAndy Shevchenko
For the sake of consistency add leading 0 to first register offsets to make them all of the same width. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-12-09i2c: designware: Switch header to use BIT() and GENMASK()Andy Shevchenko
Currently header file uses partially BIT() and GENMASK() macros. Switch it to use those macros in all cases where it's applicable for the sake of consistency. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-06-23i2c: designware: Adjust bus speed independently of ACPIAndy Shevchenko
John Stultz reported that commit f9288fcc5c615 ("i2c: designware: Move ACPI parts into common module") caused a regression on the HiKey board where adv7511 HDMI bridge driver wasn't probing anymore due the I2C bus failed to start. It seems the change caused the bus speed being zero when CONFIG_ACPI not set and neither speed based on "clock-frequency" device property or default fast mode is set. Fix this by splitting i2c_dw_acpi_adjust_bus_speed() to i2c_dw_acpi_round_bus_speed() and i2c_dw_adjust_bus_speed(), where the latter one has the code that runs independently of ACPI. Fixes: f9288fcc5c615 ("i2c: designware: Move ACPI parts into common module") Reported-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30i2c: designware: Add Baikal-T1 System I2C supportSerge Semin
Baikal-T1 System Controller is equipped with a dedicated I2C Controller which functionality is based on the DW APB I2C IP-core, the only difference in a way it' registers are accessed. There are three access register provided in the System Controller registers map, which indirectly address the normal DW APB I2C registers space. So in order to have the Baikal-T1 System I2C Controller supported by the common DW APB I2C driver we created a dedicated Dw I2C controller model quirk, which retrieves the syscon regmap from the parental dt node and creates a new regmap based on it. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30i2c: designware: Convert driver to using regmap APISerge Semin
Seeing the DW I2C driver is using flags-based accessors with two conditional clauses it would be better to replace them with the regmap API IO methods and to initialize the regmap object with read/write callbacks specific to the controller registers map implementation. This will be also handy for the drivers with non-standard registers mapping (like an embedded into the Baikal-T1 System Controller DW I2C block, which glue-driver is a part of this series). As before the driver tries to detect the mapping setup at probe stage and creates a regmap object accordingly, which will be used by the rest of the code to correctly access the controller registers. In two places it was appropriate to convert the hand-written read-modify-write and read-poll-loop design patterns to the corresponding regmap API ready-to-use methods. Note the regmap IO methods return value is checked only at the probe stage. The rest of the code won't do this because basically we have MMIO-based regmap so non of the read/write methods can fail (this also won't be needed for the Baikal-T1-specific I2C controller). Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [wsa: fix type of 'rx_valid' and remove outdated kdoc var description] Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-30i2c: designware: Discard Cherry Trail model flagSerge Semin
A PM workaround activated by the flag MODEL_CHERRYTRAIL has been removed since commit 9cbeeca05049 ("i2c: designware: Remove Cherry Trail PMIC I2C bus pm_disabled workaround"), but the flag most likely by mistake has been left in the Dw I2C drivers. Let's remove it. Since MODEL_MSCC_OCELOT is the only model-flag left, redefine it to be 0x100 so setting a very first bit in the MODEL_MASK bits range. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22i2c: designware: Move ACPI parts into common moduleAndy Shevchenko
For possible code reuse in the future, move ACPI parts into common module. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22i2c: designware: Move i2c_dw_validate_speed() helper to a common codeAndy Shevchenko
In order to export array supported speed for wider use, move it to a header along with i2c_dw_validate_speed() helper moved to a common code. No functional changes intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22i2c: designware: Include proper headers in i2c-desingware-core.hAndy Shevchenko
This header is a user of some generic ones, include them respectively. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-22i2c: designware: Get rid of PCI driver specifics in common codeAndy Shevchenko
Do not spread PCI specifics over common code. It seems to be a layering violation which can be easily avoided. Refactor PCI driver and drop PCI specifics from common code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13i2c: designware: Rename i2c_dw_probe() to i2c_dw_probe_master()Andy Shevchenko
As a preparatory patch to support slave mode for PCI enumerated devices rename i2c_dw_probe() to i2c_dw_probe_master() and split common i2c_dw_probe() as inline helper. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-05-13i2c: designware: Move configuration routines to respective modulesAndy Shevchenko
Move configuration routines to respective modules, i.e. master and slave. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-03-21i2c: designware: Discard i2c_dw_read_comp_param() functionSerge Semin
There is no code left in the kernel which would be using the function. So just remove it. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-21i2c: designware: Detect the FIFO size in the common codeSerge Semin
The problem with detecting the FIFO depth in the platform driver is that in order to implement this we have to access the controller IC_COMP_PARAM_1 register. Currently it's done before the i2c_dw_set_reg_access() method execution, which is errors prone since the method determines the registers endianness and access mode and we can't use dw_readl/dw_writel accessors before this information is retrieved. We also can't move the i2c_dw_set_reg_access() function invocation to after the master/slave probe functions call (when endianness and access mode are determined), since the FIFO depth information is used by them for initializations. So in order to fix the problem we have no choice but to move the FIFO size detection methods to the common code and call it at the probe stage. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20i2c: designware: Add support for an interface clockPhil Edworthy
The Synopsys I2C Controller has an interface clock, but most SoCs hide this away. However, on some SoCs you need to explicitly enable the interface clock in order to access the registers. Therefore, add support for an optional interface clock. Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> Signed-off-by: Gareth Williams <gareth.williams.jx@renesas.com> Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: designware: Do not allow i2c_dw_xfer() calls while suspendedHans de Goede
On most Intel Bay- and Cherry-Trail systems the PMIC is connected over I2C and the PMIC is accessed through various means by the _PS0 and _PS3 ACPI methods (power on / off methods) of various devices. This leads to suspend/resume ordering problems where a device may be resumed and get its _PS0 method executed before the I2C controller is resumed. On Cherry Trail this leads to errors like these: i2c_designware 808622C1:06: controller timed out ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion] ACPI Error: Method parse/execution failed \_SB.P18W._ON, AE_ERROR video LNXVIDEO:00: Failed to change power state to D0 But on Bay Trail this caused I2C reads to seem to succeed, but they end up returning wrong data, which ends up getting written back by the typical read-modify-write cycle done to turn on various power-resources. Debugging the problems caused by this silent data corruption is quite nasty. This commit adds a check which disallows i2c_dw_xfer() calls to happen until the controller's resume method has completed. Which turns the silent data corruption into getting these errors in dmesg instead: i2c_designware 80860F41:04: Error i2c_dw_xfer call while suspended ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion] ACPI Error: Method parse/execution failed \_SB.PCI0.GFX0._PS0, AE_ERROR Which is much better. Note the above errors are an example of issues which this patch will help to debug, the actual fix requires fixing the suspend order and this has been fixed by a different commit. Note the setting / clearing of the suspended flag in the suspend / resume methods is NOT protected by i2c_lock_bus(). This is intentional as these methods get called from i2c_dw_xfer() (through pm_runtime_get/put) a nd i2c_dw_xfer() is called with the i2c_bus_lock held, so otherwise we would deadlock. This means that there is a theoretical race between a non runtime suspend and the suspended check in i2c_dw_xfer(), this is not a problem since normally we should not hit the race and this check is primarily a debugging tool so hitting the check if there are suspend/resume ordering problems does not need to be 100% reliable. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-10-30Merge tag 'acpi-4.20-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI updates from Rafael Wysocki: "Rework the handling of the P-unit semaphore on Intel Baytrail and Cherrytrail systems to avoid race conditions and excessive overhead related to it (Hans de Goede)" * tag 'acpi-4.20-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI / PMIC: xpower: Add depends on IOSF_MBI to Kconfig entry i2c: designware: Cleanup bus lock handling ACPI / PMIC: xpower: Block P-Unit I2C access during read-modify-write x86: baytrail/cherrytrail: Rework and move P-Unit PMIC bus semaphore code
2018-10-25i2c: designware: Cleanup bus lock handlingHans de Goede
Now that most of the special Bay- / Cherry-Trail bus lock handling has been moved to the iosf_mbi code we can simplify the remaining code a bit. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-11i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllersHans de Goede
On some Cherry Trail systems the GPU ACPI fwnode has power-resources which point to the PMIC, which is connected over a LPSS I2C controller. The GPU is a PCI device and PCI devices are powered-on at the resume_noirq resume phase. Since the GPU power-resources need the I2C controller, recent acpi_lpss.c changes now also power-up the LPSS I2C controllers on BYT and CHT devices in the resume_noirq resume phase. But during this phase the IRQ of the controller is disabled leading to these errors: i2c_designware 808622C1:06: controller timed out ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion] ACPI Error: Method parse/execution failed \_SB.P18W._ON, AE_ERROR video LNXVIDEO:00: Failed to change power state to D0 This commit makes the i2c-designware controller set the IRQF_NO_SUSPEND flag when requesting the interrupt on BYT and CHT devices, so that the IRQ is left enabled during the noirq phase, fixing this. Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> 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>
2018-09-06i2c: designware: Remove Cherry Trail PMIC I2C bus pm_disabled workaroundHans de Goede
Commit a3d411fb38c0 ("i2c: designware: Disable pm for PMIC i2c-bus even if there is no _SEM method"), always set the pm_disabled flag on the I2C7 controller, even if its bus was not shared with the PUNIT. This was a workaround for various suspend/resume issues, after the following 2 commits this workaround is no longer necessary: Commit 541527728341 ("PM: i2c-designware-platdrv: Suspend/resume at the late/early stages") Commit e6ce0ce34f65 ("ACPI / LPSS: Add device link for CHT SD card dependency on I2C") Therefor this commit removes this workaround. After this commit the pm_disabled flag is only used to indicate that the bus is shared with the PUNIT and after other recent changes we no longer call dev_pm_syscore_device(dev, true), so we are no longer actually disabling (non-runtime) pm, so this commit also renames the flag to shared_with_punit to better reflect what it is for. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-09-02i2c: designware: add MSCC Ocelot supportAlexandre Belloni
The Microsemi Ocelot I2C controller is a designware IP. It also has a second set of registers to allow tweaking SDA hold time and spike filtering. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> [wsa: made one function static] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-09-02i2c: designware: allow IP specific sda_hold_timeAlexandre Belloni
Because some old designware IPs were not supporting setting an SDA hold time, vendors developed their own solution. Add a way for the final driver to provide its own SDA hold time handling. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-20i2c: designware: Add SPDX license tagAndy Shevchenko
Replace short statement in comment with proper SPDX license tag. Note, for i2c-desingware-slave.c the identifier is chosen in accordance with MODULE_LICENSE() macro since it is visible to user. Another point to this choice is that the header seems to be copy'n'paste from the other file of this very driver. Acked-by: Luis Oliveira <Luis.Oliveira@synopsys.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-08i2c: designware: Convert to use struct i2c_timingsAndy Shevchenko
Instead of using custom variables and parser, convert the driver to use the ones provided by I2C core. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Move SDA hold time configuration to common codeJarkko Nikula
SDA hold time configuration is common to both master and slave code. It is also something that can be done once during probe and do only register write when HW needs to be reinitialized. Remove duplication and move SDA hold time configuration to common code. It will be called from slave probe and for master code from a new i2c_dw_set_timings_master() to where we will populate more probe time timing parameter setting. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Move register access detection to common codeJarkko Nikula
Move register access detection out from master and slave HW initialization code to common code. Motivation for this is to have register access configured before HW initialization and remove duplicated code. This allows to do further separation between probe time initialization and runtime reinitialization code. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-15i2c: designware: refactor low-level enable/disableAlexander Monakov
Low-level controller enable function __i2c_dw_enable is overloaded to also handle disabling. What's worse, even though the documentation requires polling the IC_ENABLE_STATUS register when disabling, this is not done: polling needs to be requested specifically by calling __i2c_dw_enable_and_wait, which can also poll on enabling, but that doesn't work if the IC_ENABLE_STATUS register is not implemented. This is quite confusing if not in fact backwards. Especially since the documentation says that disabling should be followed by polling, the driver should be using a separate function where it does one-shot disables to make the optimization stand out. This refactors the two functions so that requested status is given in the name rather than in a boolean argument. Specifically: - __i2c_dw_enable: enable without polling (in accordance with docs) - __i2c_dw_disable: disable and do poll (also as suggested by docs) - __i2c_dw_disable_nowait: disable without polling (Linux-specific) No functional change. Signed-off-by: Alexander Monakov <amonakov@ispras.ru> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> [wsa: fixed blank lines in header file] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-02-04Merge branch 'i2c/for-4.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "I2C has the following changes for you: - new flag to mark DMA safe buffers in i2c_msg. Also, some infrastructure around it. And docs. - huge refactoring of the at24 driver led by the new maintainer Bartosz - update I2C bus recovery to send STOP after recovery - conversion from gpio to gpiod for I2C bus recovery - adding a fault-injector to the i2c-gpio driver - lots of small driver improvements, and bigger ones to i2c-sh_mobile" * 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (99 commits) i2c: mv64xxx: Add myself as maintainer for this driver i2c: mv64xxx: Fix clock resource by adding an optional bus clock i2c: mv64xxx: Remove useless test before clk_disable_unprepare i2c: mxs: use true and false for boolean values i2c: meson: update doc description to fix build warnings i2c: meson: add configurable divider factors dt-bindings: i2c: update documentation for the Meson-AXG i2c: imx-lpi2c: add runtime pm support i2c: rcar: fix some trivial typos in comments i2c: davinci: fix the cpufreq transition i2c: rk3x: add proper kerneldoc header i2c: rk3x: account for const type of of_device_id.data i2c: acorn: remove outdated path from file header i2c: acorn: add MODULE_LICENSE tag i2c: rcar: implement bus recovery i2c: send STOP after successful bus recovery i2c: ensure SDA is released in recovery if SDA is controllable i2c: add 'set_sda' to bus_recovery_info i2c: add identifier in declarations for i2c_bus_recovery i2c: make kerneldoc about bus recovery more precise ...
2018-01-10PM: i2c-designware-platdrv: Optimize power managementRafael J. Wysocki
Optimize the power management in i2c-designware-platdrv by making it set the DPM_FLAG_SMART_SUSPEND and DPM_FLAG_LEAVE_SUSPENDED which allows some code to be dropped from its PM callbacks. First, setting DPM_FLAG_SMART_SUSPEND causes the intel-lpss driver to avoid resuming i2c-designware-platdrv devices in its ->prepare callback, so they can stay in runtime suspend after that point even if the direct-complete feature is not used for them. It also causes the ACPI PM domain and the PM core to avoid invoking "late" and "noirq" suspend callbacks for these devices if they are in runtime suspend at the beginning of the "late" phase of device suspend during system suspend. That guarantees dw_i2c_plat_suspend() to be called for a device only if it is not in runtime suspend. Moreover, it causes the device's runtime PM status to be set to "active" after calling dw_i2c_plat_resume() for it, so the driver doesn't need internal flags to avoid invoking either dw_i2c_plat_suspend() or dw_i2c_plat_resume() twice in a row. Second, setting DPM_FLAG_LEAVE_SUSPENDED enables the optimization allowing the device to stay suspended after system resume under suitable conditions, so again the driver doesn't need to take care of that by itself. Accordingly, the internal "suspended" and "skip_resume" flags used by the driver are not necessary any more, so drop them and simplify the driver's PM callbacks. Additionally, notice that dw_i2c_plat_complete() only needs to schedule runtime PM resume for the device if platform firmware has been involved in resuming the system, so make it call pm_resume_via_firmware() to check that. Also make it check the runtime PM status of the device instead of its direct_complete flag which also works if the device remained suspended due to the DPM_FLAG_LEAVE_SUSPENDED driver flag. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
2017-11-27i2c: designware: add i2c gpio recovery optionTim Sander
This patch contains much input from Phil Reid and has been tested on Intel/Altera Cyclone V SOC Hardware with Altera GPIO's for the SCL and SDA GPIO's. Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Tim Sander <tim@krieglstein.org> Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>