From aef79e189ba2b32f78bd35daf2c0b41f3868a321 Mon Sep 17 00:00:00 2001 From: Carlos Song Date: Tue, 10 Sep 2024 13:16:25 +0800 Subject: i3c: master: support to adjust first broadcast address speed According to I3C spec 6.2 Timing Specification, the Open Drain High Period of SCL Clock timing for first broadcast address should be adjusted to 200ns at least. I3C device working as i2c device will see the broadcast to close its Spike Filter then change to work at I3C mode. After that I3C open drain SCL high level should be adjusted back. Signed-off-by: Carlos Song Reviewed-by: Miquel Raynal Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20240910051626.4052552-1-carlos.song@nxp.com Signed-off-by: Alexandre Belloni --- drivers/i3c/master.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers') diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index 7028f03c2c42..6f3eb710a75d 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -1868,6 +1868,12 @@ static int i3c_master_bus_init(struct i3c_master_controller *master) goto err_bus_cleanup; } + if (master->ops->set_speed) { + ret = master->ops->set_speed(master, I3C_OPEN_DRAIN_SLOW_SPEED); + if (ret) + goto err_bus_cleanup; + } + /* * Reset all dynamic address that may have been assigned before * (assigned by the bootloader for example). @@ -1876,6 +1882,12 @@ static int i3c_master_bus_init(struct i3c_master_controller *master) if (ret && ret != I3C_ERROR_M2) goto err_bus_cleanup; + if (master->ops->set_speed) { + master->ops->set_speed(master, I3C_OPEN_DRAIN_NORMAL_SPEED); + if (ret) + goto err_bus_cleanup; + } + /* Disable all slave events before starting DAA. */ ret = i3c_master_disec_locked(master, I3C_BROADCAST_ADDR, I3C_CCC_EVENT_SIR | I3C_CCC_EVENT_MR | -- cgit v1.2.3