Subject: [PATCH V2 5/8] serial: at91: support run time switch transfer mode

From: [email-masked] (elen.song)
Date: Thu, 18 Jul 2013 17:21:00 +0800

Hi JC:
On 7/18/2013 4:15 PM, Jean-Christophe PLAGNIOL-VILLARD wrote:
> On 10:43 Tue 16 Jul     , Elen Song wrote:
>> We will switch to pio mode when request of dma or pdc fail.
>> But soon or later, when the request is success, the transfer mode can switch to them at
>> next open serial port action.
>> So in startup stage, we should get original transfer mode.
> You need to update the Documentation of the binding to said the driver support
> dmas bindings for the new IP

one question, it seems the document should write like:

use DMA:
     usart0: serial at f001c000{
         compatible = "atmel,at91sam9260-usart";
         dmas = <&dma0 2 AT91_DMA_CFG_PER_ID(3)>,
                      <&dma0 2 
(AT91_DMA_CFG_PER_ID(3)|AT91_DMA_CFG_FIFOCFG_ASAP)>;
         dma-names = "tx","rx";
};

Should I replace macros with typical values?

Best regards
> and please use true/false for boolean
>
> and check the white space
>> Signed-off-by: Elen Song <[email-masked]>
>> ---
>>   drivers/tty/serial/atmel_serial.c |  139 +++++++++++++++++++++----------------
>>   1 file changed, 80 insertions(+), 59 deletions(-)
>>
>> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
>> index 298b58c..ad787fd1 100644
>> --- a/drivers/tty/serial/atmel_serial.c
>> +++ b/drivers/tty/serial/atmel_serial.c
>> @@ -1371,6 +1371,80 @@ static void atmel_tasklet_func(unsigned long data)
>>   	spin_unlock(&port->lock);
>>   }
>>   
>> +static int atmel_init_property(struct atmel_uart_port *atmel_port,
>> +				struct platform_device *pdev)
>> +{
>> +	struct device_node *np = pdev->dev.of_node;
>> +	struct atmel_uart_data *pdata = pdev->dev.platform_data;
>> +
>> +	if (np) {
>> +		/* DMA/PDC usage specification */
>> +		if (of_get_property(np, "atmel,use-dma-rx", NULL)) {
>> +			if (of_get_property(np, "dmas", NULL)) {
>> +				atmel_port->use_dma_rx  = 1;
>> +				atmel_port->use_pdc_rx  = 0;
>> +			} else {
>> +				atmel_port->use_dma_rx  = 0;
>> +				atmel_port->use_pdc_rx  = 1;
>> +			}
>> +		} else {
>> +			atmel_port->use_dma_rx  = 0;
>> +			atmel_port->use_pdc_rx  = 0;
>> +		}
>> +
>> +		if (of_get_property(np, "atmel,use-dma-tx", NULL)) {
>> +			if (of_get_property(np, "dmas", NULL)) {
>> +				atmel_port->use_dma_tx  = 1;
>> +				atmel_port->use_pdc_tx  = 0;
>> +			} else {
>> +				atmel_port->use_dma_tx  = 0;
>> +				atmel_port->use_pdc_tx  = 1;
>> +			}
>> +		} else {
>> +			atmel_port->use_dma_tx  = 0;
>> +			atmel_port->use_pdc_tx  = 0;
>> +		}
>> +
>> +	} else {
>> +		atmel_port->use_pdc_rx  = pdata->use_dma_rx;
>> +		atmel_port->use_pdc_tx  = pdata->use_dma_tx;
>> +		atmel_port->use_dma_rx  = 0;
>> +		atmel_port->use_dma_tx  = 0;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void atmel_init_rs485(struct atmel_uart_port *atmel_port,
>> +				struct platform_device *pdev)
>> +{
>> +	struct device_node *np = pdev->dev.of_node;
>> +	struct atmel_uart_data *pdata = pdev->dev.platform_data;
>> +
>> +	if (np) {
>> +		u32 rs485_delay[2];
>> +		/* rs485 properties */
>> +		if (of_property_read_u32_array(np, "rs485-rts-delay",
>> +					rs485_delay, 2) == 0) {
>> +			struct serial_rs485 *rs485conf = &atmel_port->rs485;
>> +
>> +			rs485conf->delay_rts_before_send = rs485_delay[0];
>> +			rs485conf->delay_rts_after_send = rs485_delay[1];
>> +			rs485conf->flags = 0;
>> +
>> +		if (of_get_property(np, "rs485-rx-during-tx", NULL))
>> +			rs485conf->flags |= SER_RS485_RX_DURING_TX;
>> +
>> +		if (of_get_property(np, "linux,rs485-enabled-at-boot-time",
>> +								NULL))
>> +			rs485conf->flags |= SER_RS485_ENABLED;
>> +		}
>> +	} else {
>> +		atmel_port->rs485       = pdata->rs485;
>> +	}
>> +
>> +}
>> +
>>   static void atmel_set_ops(struct uart_port *port)
>>   {
>>   	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
>> @@ -1409,6 +1483,7 @@ static void atmel_set_ops(struct uart_port *port)
>>    */
>>   static int atmel_startup(struct uart_port *port)
>>   {
>> +	struct platform_device *pdev = to_platform_device(port->dev);
>>   	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
>>   	struct tty_struct *tty = port->state->port.tty;
>>   	int retval;
>> @@ -1433,6 +1508,8 @@ static int atmel_startup(struct uart_port *port)
>>   	/*
>>   	 * Initialize DMA (if necessary)
>>   	 */
>> +	atmel_init_property(atmel_port, pdev);
>> +
>>   	if (atmel_port->prepare_rx) {
>>   		retval = atmel_port->prepare_rx(port);
>>   		if (retval < 0)
>> @@ -1878,55 +1955,6 @@ static struct uart_ops atmel_pops = {
>>   #endif
>>   };
>>   
>> -static void atmel_of_init_port(struct atmel_uart_port *atmel_port,
>> -					 struct device_node *np)
>> -{
>> -	u32 rs485_delay[2];
>> -
>> -	/* DMA/PDC usage specification */
>> -	if (of_get_property(np, "atmel,use-dma-rx", NULL)) {
>> -		if (of_get_property(np, "dmas", NULL)) {
>> -			atmel_port->use_dma_rx	= 1;
>> -			atmel_port->use_pdc_rx	= 0;
>> -		} else {
>> -			atmel_port->use_dma_rx	= 0;
>> -			atmel_port->use_pdc_rx	= 1;
>> -		}
>> -	} else {
>> -		atmel_port->use_dma_rx	= 0;
>> -		atmel_port->use_pdc_rx	= 0;
>> -	}
>> -
>> -	if (of_get_property(np, "atmel,use-dma-tx", NULL)) {
>> -		if (of_get_property(np, "dmas", NULL)) {
>> -			atmel_port->use_dma_tx	= 1;
>> -			atmel_port->use_pdc_tx	= 0;
>> -		} else {
>> -			atmel_port->use_dma_tx	= 0;
>> -			atmel_port->use_pdc_tx	= 1;
>> -		}
>> -	} else {
>> -		atmel_port->use_dma_tx	= 0;
>> -		atmel_port->use_pdc_tx	= 0;
>> -	}
>> -
>> -	/* rs485 properties */
>> -	if (of_property_read_u32_array(np, "rs485-rts-delay",
>> -					    rs485_delay, 2) == 0) {
>> -		struct serial_rs485 *rs485conf = &atmel_port->rs485;
>> -
>> -		rs485conf->delay_rts_before_send = rs485_delay[0];
>> -		rs485conf->delay_rts_after_send = rs485_delay[1];
>> -		rs485conf->flags = 0;
>> -
>> -		if (of_get_property(np, "rs485-rx-during-tx", NULL))
>> -			rs485conf->flags |= SER_RS485_RX_DURING_TX;
>> -
>> -		if (of_get_property(np, "linux,rs485-enabled-at-boot-time", NULL))
>> -			rs485conf->flags |= SER_RS485_ENABLED;
>> -	}
>> -}
>> -
>>   /*
>>    * Configure the port from the platform device resource info.
>>    */
>> @@ -1936,17 +1964,10 @@ static void atmel_init_port(struct atmel_uart_port *atmel_port,
>>   	struct uart_port *port = &atmel_port->uart;
>>   	struct atmel_uart_data *pdata = pdev->dev.platform_data;
>>   
>> -	if (pdev->dev.of_node) {
>> -		atmel_of_init_port(atmel_port, pdev->dev.of_node);
>> -	} else {
>> -		atmel_port->use_pdc_rx	= pdata->use_dma_rx;
>> -		atmel_port->use_pdc_tx	= pdata->use_dma_tx;
>> -		atmel_port->use_dma_rx	= 0;
>> -		atmel_port->use_dma_tx	= 0;
>> -		atmel_port->rs485	= pdata->rs485;
>> -	}
>> +	if (!atmel_init_property(atmel_port, pdev))
>> +		atmel_set_ops(port);
>>   
>> -	atmel_set_ops(port);
>> +	atmel_init_rs485(atmel_port, pdev);
>>   
>>   	port->iotype		= UPIO_MEM;
>>   	port->flags		= UPF_BOOT_AUTOCONF;
>> -- 
>> 1.7.9.5
>>