Messages in this thread | | | Date | Sat, 18 Oct 2014 22:06:15 +0100 | From | One Thousand Gnomes <> | Subject | Re: [PATCH v2 5/5] tty/serial: Add earlycon support for Spreadtrum serial driver |
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On Fri, 17 Oct 2014 17:54:25 +0800 Chunyan Zhang <chunyan.zhang@spreadtrum.com> wrote:
> Add serial driver for spreadtrum sharkl platform with earlycon > support at first.
> +#define UART_TXD 0x0000 > +#define UART_RXD 0x0004 > +#define UART_STS0 0x0008 > +#define UART_STS1 0x000C > +#define UART_IEN 0x0010 > +#define UART_ICLR 0x0014 > +#define UART_CTL0 0x0018 > +#define UART_CTL1 0x001C > +#define UART_CTL2 0x0020 > +#define UART_CLKD0 0x0024 > +#define UART_CLKD1 0x0028 > +#define UART_STS2 0x002C > + > +/*line status */ > +#define UART_LSR_TX_OVER (0x1<<15)
Given we use UART_ for all the 8250 defines it might be better to use something else - SHARK_LSR_TX_OVER etc to avoid future confusion
> +static void serial_sprd_putc(struct uart_port *port, int c) > +{ > + while (!(readl(port->membase + UART_STS0) & UART_LSR_TX_OVER)) > + ; > + writeb(c, port->membase + UART_TXD); > +} > + > +static void serial_sprd_early_write(struct console *con, const char *s, > + unsigned n) > +{ > + struct earlycon_device *dev = con->data; > + > + uart_console_write(&dev->port, s, n, serial_sprd_putc); > +} > + > +static int __init serial_sprd_early_console_setup( > + struct earlycon_device *device, > + const char *opt) > +{ > + if (!device->port.membase) > + return -ENODEV; > + > + device->con->write = serial_sprd_early_write; > + return 0; > +}
This seems fine but it would be useful to see both the earlycon and the main uart/console driver and how they fit together.
Alan
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