On 11/07/2015 07:39 AM, Matwey V. Kornilov wrote: > 2015-11-07 15:22 GMT+03:00 Peter Hurley <[email protected]>: >> On 11/07/2015 05:09 AM, Matwey V. Kornilov wrote: >>> Introduce new capability UART_CAP_HW485 to mark 8250 UARTs which have >>> hardware support of line direction control. >> >> Since capabilities are not exported to user-space, how will user-space >> know if the port only provides emulated 485 (eg., where only HW485 is >> acceptable)? > > I cannot imagine the case when user really has to care about > implementation details. > In both cases the user will be provided with the consistent API > (TIOCGRS485/TIOCSRS485 ioctls) resulting into the same behavior. > Could you please expand your question?
Well, the entire serial core is a 'consistent' API but yet we still report to user-space what the port type is. Same with lspci and lsusb. Regards, Peter Hurley >>> Signed-off-by: Matwey V. Kornilov <[email protected]> >>> --- >>> Changes since v1: >>> - Commit message has been wrapped >>> >>> drivers/tty/serial/8250/8250.h | 1 + >>> drivers/tty/serial/8250/8250_fintek.c | 1 + >>> drivers/tty/serial/8250/8250_lpc18xx.c | 1 + >>> drivers/tty/serial/8250/8250_pci.c | 1 + >>> 4 files changed, 4 insertions(+) >>> >>> diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h >>> index d54dcd8..92a4f47 100644 >>> --- a/drivers/tty/serial/8250/8250.h >>> +++ b/drivers/tty/serial/8250/8250.h >>> @@ -69,6 +69,7 @@ struct serial8250_config { >>> unsigned int flags; >>> }; >>> >>> +#define UART_CAP_HW485 (1 << 7) /* UART has hardware >>> direction control for RS485 */ >>> #define UART_CAP_FIFO (1 << 8) /* UART has FIFO */ >>> #define UART_CAP_EFR (1 << 9) /* UART has EFR */ >>> #define UART_CAP_SLEEP (1 << 10) /* UART has IER sleep */ >>> diff --git a/drivers/tty/serial/8250/8250_fintek.c >>> b/drivers/tty/serial/8250/8250_fintek.c >>> index 8947439..f2831a8 100644 >>> --- a/drivers/tty/serial/8250/8250_fintek.c >>> +++ b/drivers/tty/serial/8250/8250_fintek.c >>> @@ -208,6 +208,7 @@ fintek_8250_probe(struct pnp_dev *dev, const struct >>> pnp_device_id *dev_id) >>> uart.port.iobase = pnp_port_start(dev, 0); >>> uart.port.iotype = UPIO_PORT; >>> uart.port.rs485_config = fintek_8250_rs485_config; >>> + uart.capabilities = UART_CAP_HW485; >>> >>> uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF; >>> if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE) >>> diff --git a/drivers/tty/serial/8250/8250_lpc18xx.c >>> b/drivers/tty/serial/8250/8250_lpc18xx.c >>> index 99cd478..9d30276 100644 >>> --- a/drivers/tty/serial/8250/8250_lpc18xx.c >>> +++ b/drivers/tty/serial/8250/8250_lpc18xx.c >>> @@ -175,6 +175,7 @@ static int lpc18xx_serial_probe(struct platform_device >>> *pdev) >>> uart.port.private_data = data; >>> uart.port.rs485_config = lpc18xx_rs485_config; >>> uart.port.serial_out = lpc18xx_uart_serial_out; >>> + uart.capabilities = UART_CAP_HW485; >>> >>> uart.dma = &data->dma; >>> uart.dma->rxconf.src_maxburst = 1; >>> diff --git a/drivers/tty/serial/8250/8250_pci.c >>> b/drivers/tty/serial/8250/8250_pci.c >>> index 4097f3f..c7c0ae9 100644 >>> --- a/drivers/tty/serial/8250/8250_pci.c >>> +++ b/drivers/tty/serial/8250/8250_pci.c >>> @@ -1599,6 +1599,7 @@ static int pci_fintek_setup(struct serial_private >>> *priv, >>> port->port.iotype = UPIO_PORT; >>> port->port.iobase = iobase; >>> port->port.rs485_config = pci_fintek_rs485_config; >>> + port->capabilities = UART_CAP_HW485; >>> >>> data = devm_kzalloc(&pdev->dev, sizeof(u8), GFP_KERNEL); >>> if (!data) >>> >> > > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
