Hi, this series is trying to address discussion I had with Alan in past https://patchwork.kernel.org/patch/9738445/. It is moving uart_register_driver() to probe function like it is done in pl011 driver. And also introducing new function for alias compatibility checking to resolve cases where some IPs have alias and some of them not. This case is detected in pl011_probe_dt_alias() but not properly solved. Also keep status of free ids/minor numbers in bitmap to know what's the next unallocated number. The same solution can be used in pl011, uart16550 and uartlite to really get unified kernel. Tested on these use cases: Notes: ff000000 is the first PS uart listed in dtsi ff010000 is the second PS uart listed in dtsi Standard zcu102 setting serial0 = &uart0; serial1 = &uart1; [ 0.196628] ff000000.serial: ttyPS0 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.642542] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps Swapped zcu102 setting serial0 = &uart1; serial1 = &uart0; [ 0.196472] ff000000.serial: ttyPS1 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.196824] ff010000.serial: ttyPS0 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps uart0 on alias higher then MAX uart ports serial0 = &uart1; serial200 = &uart0; [ 0.176793] ff000000.serial: ttyPS200 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.177288] ff010000.serial: ttyPS0 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps Both uarts on higher aliases serial1 = &uart1; serial2 = &uart0; [ 0.196470] ff000000.serial: ttyPS2 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.196823] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps uart0 not listed but it is probed first that's why should be ttyPS0 but there is uart1 via alias serial0 = &uart1; [ 0.176656] xuartps ff000000.serial: No serial alias passed. Using the first free id [ 0.176671] xuartps ff000000.serial: Validate id 0 [ 0.176680] xuartps ff000000.serial: The empty id is 0 [ 0.176692] xuartps ff000000.serial: ID 0 already taken - skipped [ 0.176701] xuartps ff000000.serial: Validate id 1 [ 0.176710] xuartps ff000000.serial: The empty id is 1 [ 0.176719] xuartps ff000000.serial: Selected ID 1 allocation passed [ 0.176760] ff000000.serial: ttyPS1 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.177104] ff010000.serial: ttyPS0 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps uart0 not listed but it is probed first that's why should be ttyPS0 serial1 = &uart1; [ 0.176661] xuartps ff000000.serial: No serial alias passed. Using the first free id [ 0.176676] xuartps ff000000.serial: Validate id 0 [ 0.176686] xuartps ff000000.serial: The empty id is 0 [ 0.176696] xuartps ff000000.serial: Selected ID 0 allocation passed [ 0.176737] ff000000.serial: ttyPS0 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.177069] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps uarts not listed in aliases list [ 0.176673] xuartps ff000000.serial: No serial alias passed. Using the first free id [ 0.176687] xuartps ff000000.serial: Validate id 0 [ 0.176697] xuartps ff000000.serial: The empty id is 0 [ 0.176707] xuartps ff000000.serial: Selected ID 0 allocation passed [ 0.176746] ff000000.serial: ttyPS0 at MMIO 0xff000000 (irq = 33, base_baud = 6250000) is a xuartps [ 0.177057] xuartps ff010000.serial: No serial alias passed. Using the first free id [ 0.177070] xuartps ff010000.serial: Validate id 0 [ 0.177079] xuartps ff010000.serial: The empty id is 0 [ 0.177089] xuartps ff010000.serial: Selected ID 0 allocation failed [ 0.177098] xuartps ff010000.serial: Validate id 1 [ 0.177107] xuartps ff010000.serial: The empty id is 1 [ 0.177116] xuartps ff010000.serial: Selected ID 1 allocation passed [ 0.177149] ff010000.serial: ttyPS1 at MMIO 0xff010000 (irq = 34, base_baud = 6250000) is a xuartps Thanks, Michal Michal Simek (3): of: base: Introduce of_alias_check_id() to check alias IDs serial: uartps: Move register to probe based on run time detection serial: uartps: Change uart ports allocation drivers/of/base.c | 49 +++++++++++ drivers/tty/serial/xilinx_uartps.c | 128 +++++++++++++++++++++++------ include/linux/of.h | 2 + 3 files changed, 153 insertions(+), 26 deletions(-) -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html