Re: [Nios2-dev] [PATCH 2/2] serial: Add driver for the Altera UART

[Ian Abbott]

On 06/05/10 11:44, Ian Abbott wrote:
> On Wed, 2010-05-05 at 09:35 +0100, Tobias Klauser wrote:
>> Add an UART driver for the UART component available as a SOPC (System on
>> Programmable Chip) component for Altera FPGAs.
> [...]
> 
>> +static void altera_uart_start_tx(struct uart_port *port)
>> +{
>> +       struct altera_uart *pp = container_of(port, struct altera_uart, port);
>> +       unsigned long flags;
>> +
>> +       spin_lock_irqsave(&port->lock, flags);
>> +       pp->imr |= ALTERA_UART_CONTROL_TRDY_MSK;
>> +       writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
>> +       spin_unlock_irqrestore(&port->lock, flags);
>> +}
>> +
>> +static void altera_uart_stop_tx(struct uart_port *port)
>> +{
>> +       struct altera_uart *pp = container_of(port, struct altera_uart, port);
>> +       unsigned long flags;
>> +
>> +       spin_lock_irqsave(&port->lock, flags);
>> +       pp->imr &= ~ALTERA_UART_CONTROL_TRDY_MSK;
>> +       writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
>> +       spin_unlock_irqrestore(&port->lock, flags);
>> +}
>> +
>> +static void altera_uart_stop_rx(struct uart_port *port)
>> +{
>> +       struct altera_uart *pp = container_of(port, struct altera_uart, port);
>> +       unsigned long flags;
>> +
>> +       spin_lock_irqsave(&port->lock, flags);
>> +       pp->imr &= ~ALTERA_UART_CONTROL_RRDY_MSK;
>> +       writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
>> +       spin_unlock_irqrestore(&port->lock, flags);
>> +}
> 
> Those four functions shouldn't grab port->lock because the caller in
> serial_core.c grabs it before calling them.

Oh, and that also applies to altera_uart_set_mctrl() - the caller grabs
port->lock before calling it.

-- 
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbotti@xxxxxxxxx>        )=-
-=( Tel: +44 (0)161 477 1898   FAX: +44 (0)161 718 3587         )=-
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