kernel/git/stable/linux.git/drivers/i2c, branch linux-6.17.y

i2c: spacemit: fix detect issue

2025-12-18T13:00:12+00:00

[ Upstream commit 25faa5364638b86ec0d0edb4486daa9d40a0be8f ] This commit addresses two issues causing i2c detect to fail. The identified issues are: 1. Incorrect error handling for BED (Bus Error No ACK/NAK): Before this commit, Both ALD (Arbitration Loss Detected) and BED returned -EAGAIN. 2. Missing interrupt status clear after initialization in xfer(): On the K1 SoC, simply fixing the first issue changed the error from -EAGAIN to -ETIMEOUT. Through tracing, it was determined that this is likely due to MSD (Master Stop Detected) latency issues. That means the MSD bit in the ISR may still be set on the next transfer. As a result, the controller won't work — we can see from the scope that it doesn't issue any signal. (This only occurs during rapid consecutive I2C transfers. That explains why the issue only shows up with i2cdetect.) With these two fixes, i2c device detection now functions correctly on the K1 SoC. Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC") Tested-by: Aurelien Jarno Signed-off-by: Troy Mitchell Reviewed-by: Aurelien Jarno Tested-by: Michael Opdenacker Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20251113-fix-k1-detect-failure-v2-1-b02a9a74f65a@linux.spacemit.com Signed-off-by: Sasha Levin

i2c: designware: Add disabling clocks when probe fails

2025-10-15T10:03:38+00:00

[ Upstream commit c149841b069ccc6e480b00e11f35a57b5d88c7bb ] After an error occurs during probing state, dw_i2c_plat_pm_cleanup() is called. However, this function doesn't disable clocks and the clock-enable count keeps increasing. Should disable these clocks explicitly. Fixes: 7272194ed391f ("i2c-designware: add minimal support for runtime PM") Co-developed-by: Kohei Ito Signed-off-by: Kohei Ito Signed-off-by: Kunihiko Hayashi Acked-by: Jarkko Nikula Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: designware: Fix clock issue when PM is disabled

2025-10-15T10:03:38+00:00

[ Upstream commit 70e633bedeeb4a7290d3b1dd9d49cc2bae25a46f ] When the driver is removed, the clocks are first enabled by calling pm_runtime_get_sync(), and then disabled with pm_runtime_put_sync(). If CONFIG_PM=y, clocks for this controller are disabled when it's in the idle state. So the clocks are properly disabled when the driver exits. Othewise, the clocks are always enabled and the PM functions have no effect. Therefore, the driver exits without disabling the clocks. # cat /sys/kernel/debug/clk/clk-pclk/clk_enable_count 18 # echo 1214a000.i2c > /sys/bus/platform/drivers/i2c_designware/bind # cat /sys/kernel/debug/clk/clk-pclk/clk_enable_count 20 # echo 1214a000.i2c > /sys/bus/platform/drivers/i2c_designware/unbind # cat /sys/kernel/debug/clk/clk-pclk/clk_enable_count 20 To ensure that the clocks can be disabled correctly even without CONFIG_PM=y, should add the following fixes: - Replace with pm_runtime_put_noidle(), which only decrements the runtime PM usage count. - Call i2c_dw_prepare_clk(false) to explicitly disable the clocks. Fixes: 7272194ed391f ("i2c-designware: add minimal support for runtime PM") Co-developed-by: Kohei Ito Signed-off-by: Kohei Ito Signed-off-by: Kunihiko Hayashi Tested-by: Jarkko Nikula Acked-by: Jarkko Nikula Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: spacemit: ensure SDA is released after bus reset

2025-10-15T10:03:38+00:00

[ Upstream commit 0de61943244dec418d396633a587adca1c350b55 ] After performing a conditional bus reset, the controller must ensure that the SDA line is actually released. Previously, the reset routine only performed a single check, which could leave the bus in a locked state in some situations. This patch introduces a loop that toggles the reset cycle and issues a reset request up to SPACEMIT_BUS_RESET_CLK_CNT_MAX times, checking SDA after each attempt. If SDA is released before the maximum count, the function returns early. Otherwise, a warning is emitted. This change improves bus recovery reliability. Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC") Signed-off-by: Troy Mitchell Reviewed-by: Aurelien Jarno Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: spacemit: check SDA instead of SCL after bus reset

2025-10-15T10:03:38+00:00

[ Upstream commit db7720ef50e0103be70a3887bc66e9c909933ad9 ] After calling spacemit_i2c_conditionally_reset_bus(), the controller should ensure that the SDA line is release before proceeding. Previously, the driver checked the SCL line instead, which does not guarantee that the bus is truly idle. This patch changes the check to verify SDA. This ensures proper bus recovery and avoids potential communication errors after a conditional reset. Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC") Reviewed-by: Aurelien Jarno Signed-off-by: Troy Mitchell Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: spacemit: disable SDA glitch fix to avoid restart delay

2025-10-15T10:03:38+00:00

[ Upstream commit 11f40684ccd84e792eced110f0a5d3d6adbdf90d ] The K1 I2C controller has an SDA glitch fix that introduces a small delay on restart signals. While this feature can suppress glitches on SDA when SCL = 0, it also delays the restart signal, which may cause unexpected behavior in some transfers. The glitch itself does not affect normal I2C operation, because the I2C specification allows SDA to change while SCL is low. To ensure correct transmission for every message, we disable the SDA glitch fix by setting the RCR.SDA_GLITCH_NOFIX bit during initialization. This guarantees that restarts are issued promptly without unintended delays. Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC") Reviewed-by: Aurelien Jarno Signed-off-by: Troy Mitchell Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: spacemit: remove stop function to avoid bus error

2025-10-15T10:03:38+00:00

[ Upstream commit 445522fe7aad6131b2747ae8c76f77266054cd84 ] Previously, STOP handling was split into two separate steps: 1) clear TB/STOP/START/ACK bits 2) issue STOP by calling spacemit_i2c_stop() This left a small window where the control register was updated twice, which can confuse the controller. While this race has not been observed with interrupt-driven transfers, it reliably causes bus errors in PIO mode. Inline the STOP sequence into the IRQ handler and ensure that control register bits are updated atomically in a single writel(). Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC") Signed-off-by: Troy Mitchell Reviewed-by: Aurelien Jarno Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: spacemit: ensure bus release check runs when wait_bus_idle() fails

2025-10-15T10:03:38+00:00

[ Upstream commit 41d6f90ef5dc2841bdd09817c63a3d6188473b9b ] spacemit_i2c_wait_bus_idle() only returns 0 on success or a negative error code on failure. Since 'ret' can never be positive, the final 'else' branch was unreachable, and spacemit_i2c_check_bus_release() was never called. This commit guarantees we attempt to release the bus whenever waiting for an idle bus fails. Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC") Reviewed-by: Aurelien Jarno Signed-off-by: Troy Mitchell Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: mediatek: fix potential incorrect use of I2C_MASTER_WRRD

2025-10-15T10:03:37+00:00

[ Upstream commit b492183652808e0f389272bf63dc836241b287ff ] The old IC does not support the I2C_MASTER_WRRD (write-then-read) function, but the current code’s handling of i2c->auto_restart may potentially lead to entering the I2C_MASTER_WRRD software flow, resulting in unexpected bugs. Instead of repurposing the auto_restart flag, add a separate flag to signal I2C_MASTER_WRRD operations. Also fix handling of msgs. If the operation (i2c->op) is I2C_MASTER_WRRD, then the msgs pointer is incremented by 2. For all other operations, msgs is simply incremented by 1. Fixes: b2ed11e224a2 ("I2C: mediatek: Add driver for MediaTek MT8173 I2C controller") Signed-off-by: Leilk.Liu Suggested-by: Chen-Yu Tsai Reviewed-by: Chen-Yu Tsai Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: rtl9300: Drop unsupported I2C_FUNC_SMBUS_I2C_BLOCK

2025-09-27T22:23:34+00:00

While applying the patch for commit ede965fd555a ("i2c: rtl9300: remove broken SMBus Quick operation support"), a conflict was incorrectly solved by adding the I2C_FUNC_SMBUS_I2C_BLOCK feature flag. But the code to handle I2C_SMBUS_I2C_BLOCK_DATA requests will be added by a separate commit. Fixes: ede965fd555a ("i2c: rtl9300: remove broken SMBus Quick operation support") Signed-off-by: Sven Eckelmann Signed-off-by: Wolfram Sang