On Tue, Aug 26, 2014 at 11:04:57AM +0800, Scott Yuan wrote:
> On x86 architecture, the configuration of serial device maybe get from ACPI
> DSDT, but the order of DSDT is not mandatory, result as array serial8250_ports
> is out of order. This situation is more obvious in multiple serial port
> mainboard. Sort it by unique id that in DSDT will fix it.
Who cares about the order, you should use the "persistant" names in
/dev/serial/ to connect to things that you really care about which is
which.
>
> Signed-off-by: Scott Yuan <scottzero0@xxxxxxxxx>
> ---
> drivers/pnp/pnpacpi/core.c | 1 +
> drivers/tty/serial/8250/8250_core.c | 40 ++++++++++++++++++++++++++++++++++++-
> drivers/tty/serial/8250/8250_pnp.c | 12 +++++++++++
> include/linux/pnp.h | 1 +
> include/linux/serial_8250.h | 2 ++
> 5 files changed, 55 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
> index a5c6cb7..84b518e 100644
> --- a/drivers/pnp/pnpacpi/core.c
> +++ b/drivers/pnp/pnpacpi/core.c
> @@ -254,6 +254,7 @@ static int __init pnpacpi_add_device(struct acpi_device *device)
> return -ENOMEM;
>
> dev->data = device;
> + dev->is_acpi = 1;
> /* .enabled means the device can decode the resources */
> dev->active = device->status.enabled;
> if (acpi_has_method(device->handle, "_SRS"))
> diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
> index 7a91c6d..0e5ece5 100644
> --- a/drivers/tty/serial/8250/8250_core.c
> +++ b/drivers/tty/serial/8250/8250_core.c
> @@ -3221,6 +3221,41 @@ static struct uart_8250_port *serial8250_find_match_or_unused(struct uart_port *
> return NULL;
> }
>
> +static struct uart_8250_port *
> +serial8250_find_match_sorted_port(struct uart_port *port)
> +{
> + int i, j;
> + struct uart_8250_port *uart;
> +
> + uart = container_of(port, struct uart_8250_port, port);
> +
> + /*
> + * We need sorted array serial8250_ports, it is sort by ACPI
> + * device unique id, so find an apropriate position to insert.
> + */
> + for (i = 0; i < nr_uarts; i++) {
> + if (serial8250_ports[i].uid == 0 ||
> + uart->uid < serial8250_ports[i].uid)
> + break;
> + }
> +
> + /*
> + * If current uid that in serial8250_ports is big than port uid,
> + * then move 8250 port data.
> + */
> + if (i < nr_uarts - 1 &&
> + uart->uid < serial8250_ports[i].uid) {
> + memmove(&serial8250_ports[i+1], &serial8250_ports[i],
> + (nr_uarts - i - 1) * sizeof(struct uart_8250_port));
Heh, no, that's crazy...
> +
> + /* modify port.line, since data moved */
> + for (j = i + 1; j < nr_uarts; j++)
> + serial8250_ports[j].port.line += 1;
> + }
> + serial8250_ports[i].uid = uart->uid;
> + return &serial8250_ports[i];
> +}
I really don't understand what you are trying to "solve" here. What is
wrong with the current kernel code? What does this patch change?
Why is acpi "special"?
greg k-h
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