linux-stable.git/drivers/i3c, branch v6.18

i3c: fix big-endian FIFO transfers

2025-09-28T22:17:22+00:00

Short MMIO transfers that are not a multiple of four bytes in size need
a special case for the final bytes, however the existing implementation
is not endian-safe and introduces an incorrect byteswap on big-endian
kernels.

This usually does not cause problems because most systems are
little-endian and most transfers are multiple of four bytes long, but
still needs to be fixed to avoid the extra byteswap.

Change the special case for both i3c_writel_fifo() and i3c_readl_fifo()
to use non-byteswapping writesl() and readsl() with a single element
instead of the byteswapping writel()/readl() that are meant for individual
MMIO registers. As data is copied between a FIFO and a memory buffer,
the writesl()/readsl() loops are typically based on __raw_readl()/
__raw_writel(), resulting in the order of bytes in the FIFO to match
the order in the buffer, regardless of the CPU endianess.

The earlier versions in the dw-i3c and i3c-master-cdns had a correct
implementation, but the generic version that was recently added broke it.

Fixes: 733b439375b4 ("i3c: master: Add inline i3c_readl_fifo() and i3c_writel_fifo()")
Cc: Manikanta Guntupalli 
Signed-off-by: Arnd Bergmann 
Reviewed-by: Jorge Marques 
Link: https://lore.kernel.org/r/20250924201837.3691486-1-arnd@kernel.org
Signed-off-by: Alexandre Belloni

i3c: master: adi: fix number of bytes written to fifo

2025-09-28T22:11:59+00:00

adi_i3c_master_wr_to_tx_fifo computes the maximum number of bytes that can be
sent to the fifo but never makes use of it, actually limit the number of bytes
sent.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202509190505.fKGvEJRa-lkp@intel.com/
Reviewed-by: Jorge Marques 
Reviewed-by: Frank Li 
Link: https://lore.kernel.org/r/20250924195600.122142-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni

i3c: Remove superfluous FIXME

2025-09-23T22:46:15+00:00

I2C adapters can already change timeout and retry parameters via IOCTL.
This allows for better tuning to workloads compared to per-adapter
defaults. So, the FIXME is not needed.

Signed-off-by: Wolfram Sang 
Reviewed-by: Frank Li 
Link: https://lore.kernel.org/r/20250923203557.18298-2-wsa+renesas@sang-engineering.com
Signed-off-by: Alexandre Belloni

i3c: master: adi: fix header location

2025-09-16T15:44:08+00:00

The adi-axi-common header has been moved to the upper directory.

Acked-by: Jorge Marques 
Link: https://lore.kernel.org/r/20250519-dev-axi-clkgen-limits-v6-3-bc4b3b61d1d4@analog.com
Acked-by: Nuno Sá 
Link: https://lore.kernel.org/r/20250916091252.39265-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni

i3c: dw: Add shutdown support to dw_i3c_master driver

2025-09-16T15:06:43+00:00

Add shutdown handler to the Synopsys DesignWare I3C master driver,
ensuring the device is gracefully disabled during system shutdown.

The shutdown handler cancels any pending hot-join work and disables
interrupts.

Signed-off-by: Manikanta Guntupalli 
Link: https://lore.kernel.org/r/20250730151207.4113708-1-manikanta.guntupalli@amd.com
Signed-off-by: Alexandre Belloni

i3c: renesas: Simplify return statement in 'renesas_i3c_daa'

2025-09-16T15:06:43+00:00

There was already a bail out for 'ret < 0', so we can always return
success at the end of the function.

Reported-by: Dan Carpenter 
Closes: https://lore.kernel.org/r/aIyzJ7HOENL1qp1l@stanley.mountain
Signed-off-by: Wolfram Sang 
Tested-by: Tommaso Merciai 
Link: https://lore.kernel.org/r/20250803211256.18513-2-wsa+renesas@sang-engineering.com
Signed-off-by: Alexandre Belloni

i3c: master: svc: Recycle unused IBI slot

2025-09-16T15:06:43+00:00

In svc_i3c_master_handle_ibi(), an IBI slot is fetched from the pool
to store the IBI payload. However, when an error condition is encountered,
the function returns without recycling the IBI slot, resulting in an IBI
slot leak.

Fixes: c85e209b799f ("i3c: master: svc: fix ibi may not return mandatory data byte")
Signed-off-by: Stanley Chu 
Reviewed-by: Frank Li 
Link: https://lore.kernel.org/r/20250829012309.3562585-3-yschu@nuvoton.com
Signed-off-by: Alexandre Belloni

i3c: master: svc: Use manual response for IBI events

2025-09-16T15:06:43+00:00

Driver wants to nack the IBI request when the target is not in the
known address list. In below code, svc_i3c_master_nack_ibi() will
cause undefined behavior when using AUTOIBI with auto response rule,
because hw always auto ack the IBI request.

    switch (ibitype) {
    case SVC_I3C_MSTATUS_IBITYPE_IBI:
            dev = svc_i3c_master_dev_from_addr(master, ibiaddr);
            if (!dev || !is_events_enabled(master, SVC_I3C_EVENT_IBI))
                    svc_i3c_master_nack_ibi(master);
            ...
            break;

AutoIBI has another issue that the controller doesn't quit AutoIBI state
after IBIWON polling timeout when there is a SDA glitch(high->low->high).
1. SDA high->low: raising an interrupt to execute IBI ISR
2. SDA low->high
3. Driver writes an AutoIBI request
4. AutoIBI process does not start because SDA is not low
5. IBIWON polling times out
6. Controller reamins in AutoIBI state and doesn't accept EmitStop request

Emitting broadcast address with IBIRESP_MANUAL avoids both issues.

Fixes: dd3c52846d59 ("i3c: master: svc: Add Silvaco I3C master driver")
Signed-off-by: Stanley Chu 
Reviewed-by: Frank Li 
Link: https://lore.kernel.org/r/20250829012309.3562585-2-yschu@nuvoton.com
Signed-off-by: Alexandre Belloni

i3c: master: Add driver for Analog Devices I3C Controller IP

2025-09-16T15:06:43+00:00

Add support for Analog Devices I3C Controller IP, an AXI-interfaced IP
core that supports I3C and I2C devices, multiple speed-grades and
I3C IBIs.

Reviewed-by: Frank Li 
Signed-off-by: Jorge Marques 
Link: https://lore.kernel.org/r/20250827-adi-i3c-master-v9-2-04413925abe1@analog.com
Signed-off-by: Alexandre Belloni

i3c: Fix default I2C adapter timeout value

2025-09-16T15:06:43+00:00

Commit 3a379bbcea0a ("i3c: Add core I3C infrastructure") set the default
adapter timeout for I2C transfers as 1000 (ms). However that parameter
is defined in jiffies not in milliseconds.

With mipi-i3c-hci driver this wasn't visible until commit c0a90eb55a69
("i3c: mipi-i3c-hci: use adapter timeout value for I2C transfers").

Fix this by setting the default timeout as HZ (CONFIG_HZ) not 1000.

Fixes: 1b84691e7870 ("i3c: dw: use adapter timeout value for I2C transfers")
Fixes: be27ed672878 ("i3c: master: cdns: use adapter timeout value for I2C transfers")
Fixes: c0a90eb55a69 ("i3c: mipi-i3c-hci: use adapter timeout value for I2C transfers")
Fixes: a747e01adad2 ("i3c: master: svc: use adapter timeout value for I2C transfers")
Fixes: d028219a9f14 ("i3c: master: Add basic driver for the Renesas I3C controller")
Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
Cc: stable@vger.kernel.org # 6.17
Signed-off-by: Jarkko Nikula 
Reviewed-by: Frank Li 
Reviewed-by: Wolfram Sang 
Link: https://lore.kernel.org/r/20250905100320.954536-1-jarkko.nikula@linux.intel.com
Signed-off-by: Alexandre Belloni