Re: [STLinux Kernel] [PATCH v2 03/10] serial: st-asc: Read in all Pinctrl states

[Peter Griffin]

On Wed, 01 Feb 2017, Lee Jones wrote:

> There are now 2 possible separate/different Pinctrl states which can
> be provided from platform data.  One which encompasses the lines
> required for HW flow-control (CTS/RTS) and another which does not
> specify these lines, such that they can be used via GPIO mechanisms
> for manually toggling (i.e. from a request by `stty`).
> 
> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>

Acked-by: Peter Griffin <peter.griffin@xxxxxxxxxx>

> ---
>  drivers/tty/serial/st-asc.c | 29 +++++++++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
> index 397df50..1058020 100644
> --- a/drivers/tty/serial/st-asc.c
> +++ b/drivers/tty/serial/st-asc.c
> @@ -18,6 +18,7 @@
>  #include <linux/serial.h>
>  #include <linux/console.h>
>  #include <linux/sysrq.h>
> +#include <linux/pinctrl/consumer.h>
>  #include <linux/platform_device.h>
>  #include <linux/io.h>
>  #include <linux/irq.h>
> @@ -37,10 +38,16 @@
>  #define ASC_FIFO_SIZE 16
>  #define ASC_MAX_PORTS 8
>  
> +/* Pinctrl states */
> +#define DEFAULT		0
> +#define NO_HW_FLOWCTRL	1
> +
>  struct asc_port {
>  	struct uart_port port;
>  	struct gpio_desc *rts;
>  	struct clk *clk;
> +	struct pinctrl *pinctrl;
> +	struct pinctrl_state *states[2];
>  	unsigned int hw_flow_control:1;
>  	unsigned int force_m1:1;
>  };
> @@ -694,6 +701,7 @@ static int asc_init_port(struct asc_port *ascport,
>  {
>  	struct uart_port *port = &ascport->port;
>  	struct resource *res;
> +	int ret;
>  
>  	port->iotype	= UPIO_MEM;
>  	port->flags	= UPF_BOOT_AUTOCONF;
> @@ -720,6 +728,27 @@ static int asc_init_port(struct asc_port *ascport,
>  	WARN_ON(ascport->port.uartclk == 0);
>  	clk_disable_unprepare(ascport->clk);
>  
> +	ascport->pinctrl = devm_pinctrl_get(&pdev->dev);
> +	if (IS_ERR(ascport->pinctrl)) {
> +		ret = PTR_ERR(ascport->pinctrl);
> +		dev_err(&pdev->dev, "Failed to get Pinctrl: %d\n", ret);
> +	}
> +
> +	ascport->states[DEFAULT] =
> +		pinctrl_lookup_state(ascport->pinctrl, "default");
> +	if (IS_ERR(ascport->states[DEFAULT])) {
> +		ret = PTR_ERR(ascport->states[DEFAULT]);
> +		dev_err(&pdev->dev,
> +			"Failed to look up Pinctrl state 'default': %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* "no-hw-flowctrl" state is optional */
> +	ascport->states[NO_HW_FLOWCTRL] =
> +		pinctrl_lookup_state(ascport->pinctrl, "no-hw-flowctrl");
> +	if (IS_ERR(ascport->states[NO_HW_FLOWCTRL]))
> +		ascport->states[NO_HW_FLOWCTRL] = NULL;
> +
>  	return 0;
>  }
>