[PATCHv3 2/2] tty: of_serial: support for 32 bit accesses
Grant Likely
grant.likely at secretlab.ca
Tue Jun 28 02:57:26 EST 2011
On Mon, Jun 27, 2011 at 6:32 AM, Jamie Iles <jamie at jamieiles.com> wrote:
> Some platforms e.g. TI Davinci require 32-bit accesses to the UARTs.
> The of_serial driver currently registers all UARTs as UPIO_MEM. Add a
> new attribute "io-width" to allow the port to be registered with
> different IO width requirements.
>
> Acked-by: Alan Cox <alan at linux.intel.com>
> Acked-by: Grant Likely <grant.likely at secretlab.ca>
> Signed-off-by: Jamie Iles <jamie at jamieiles.com>
Alan, who should pick this series up? Should I take it via the
devicetree/next tree?
g.
> ---
> .../devicetree/bindings/tty/serial/of-serial.txt | 3 +++
> drivers/tty/serial/of_serial.c | 17 +++++++++++++++++
> 2 files changed, 20 insertions(+), 0 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/tty/serial/of-serial.txt b/Documentation/devicetree/bindings/tty/serial/of-serial.txt
> index 35e53ae..93260d0 100644
> --- a/Documentation/devicetree/bindings/tty/serial/of-serial.txt
> +++ b/Documentation/devicetree/bindings/tty/serial/of-serial.txt
> @@ -21,6 +21,9 @@ Optional properties:
> - reg-shift : quantity to shift the register offsets by.
> - used-by-rtas : set to indicate that the port is in use by the OpenFirmware
> RTAS and should not be registered.
> +- io-width : the size (in bytes) of the IO accesses that should be performed
> + on the device. There are some systems that require 32-bit accesses to the
> + UART (e.g. TI davinci).
>
> Example:
>
> diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
> index c911b24..dfcad6f 100644
> --- a/drivers/tty/serial/of_serial.c
> +++ b/drivers/tty/serial/of_serial.c
> @@ -65,6 +65,23 @@ static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
>
> port->irq = irq_of_parse_and_map(np, 0);
> port->iotype = UPIO_MEM;
> + prop = of_get_property(np, "io-width", &prop_size);
> + if (prop && (prop_size == sizeof(u32))) {
> + switch (be32_to_cpup(prop)) {
> + case 1:
> + port->iotype = UPIO_MEM;
> + break;
> + case 4:
> + port->iotype = UPIO_MEM32;
> + break;
> + default:
> + dev_warn(&ofdev->dev,
> + "unsupported io width (%d bytes)\n",
> + be32_to_cpup(prop));
> + return -EINVAL;
> + }
> + }
> +
> port->type = type;
> port->uartclk = be32_to_cpup(clk);
> port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
> --
> 1.7.4.1
>
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>
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
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