| Message ID | 20170201143145.31962-1-lee.jones@linaro.org |
|---|---|
| Headers | show |
| Series | serial: st-asc: Allow handling of RTS line | expand |
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@linaro.org> Acked-by: Peter Griffin <peter.griffin@linaro.org> > --- > 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; > } >
On Wed, 01 Feb 2017, Lee Jones wrote: > The initial binding 'st,hw-flow-control' isn't used anywhere, in neither > in upstream nor downstream kernels. It isn't even documented in > dt-bindings, so we can safely assume it's safe to swap to the generic > one. > > Signed-off-by: Lee Jones <lee.jones@linaro.org> Acked-by: Peter Griffin <peter.griffin@linaro.org> > --- > drivers/tty/serial/st-asc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c > index e521078..bcf1d33 100644 > --- a/drivers/tty/serial/st-asc.c > +++ b/drivers/tty/serial/st-asc.c > @@ -794,7 +794,7 @@ static struct asc_port *asc_of_get_asc_port(struct platform_device *pdev) > return NULL; > > asc_ports[id].hw_flow_control = of_property_read_bool(np, > - "st,hw-flow-control"); > + "uart-has-rtscts"); > asc_ports[id].force_m1 = of_property_read_bool(np, "st,force_m1"); > asc_ports[id].port.line = id; > asc_ports[id].rts = NULL;