Hi Joel, On Fri, 2017-05-26 at 11:55 +1000, Joel Stanley wrote: > This adds the hooks for an optional reset controller in the 8250 device > tree node. > > Signed-off-by: Joel Stanley <joel@xxxxxxxxx> > > --- > v2: > Address Philipp's comments. Thanks for the review! > - use _shared variant > - remove unnecessary error handling > > Documentation/devicetree/bindings/serial/8250.txt | 1 + > drivers/tty/serial/8250/8250_of.c | 10 ++++++++++ > 2 files changed, 11 insertions(+) > > diff --git a/Documentation/devicetree/bindings/serial/8250.txt b/Documentation/devicetree/bindings/serial/8250.txt > index 10276a46ecef..63e32393f82b 100644 > --- a/Documentation/devicetree/bindings/serial/8250.txt > +++ b/Documentation/devicetree/bindings/serial/8250.txt > @@ -45,6 +45,7 @@ Optional properties: > property. > - tx-threshold: Specify the TX FIFO low water indication for parts with > programmable TX FIFO thresholds. > +- resets : phandle + reset specifier pairs > > Note: > * fsl,ns16550: > diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c > index 1cbadafc6889..e95cc9698c32 100644 > --- a/drivers/tty/serial/8250/8250_of.c > +++ b/drivers/tty/serial/8250/8250_of.c > @@ -19,11 +19,13 @@ > #include <linux/of_irq.h> > #include <linux/of_platform.h> > #include <linux/clk.h> > +#include <linux/reset.h> > > #include "8250.h" > > struct of_serial_info { > struct clk *clk; > + struct reset_control *rst; > int type; > int line; > }; > @@ -132,6 +134,13 @@ static int of_platform_serial_setup(struct platform_device *ofdev, > } > } > > + info->rst = devm_reset_control_get_optional_shared(&ofdev->dev, NULL); > + if (IS_ERR(info->rst)) > + goto out; > + ret = reset_control_deassert(info->rst); > + if (ret) > + goto out; > + > port->type = type; > port->uartclk = clk; > port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP > @@ -231,6 +240,7 @@ static int of_platform_serial_remove(struct platform_device *ofdev) > > if (info->clk) > clk_disable_unprepare(info->clk); > + reset_control_assert(info->rst); The clock is enabled before the reset is deasserted in of_platform_serial_setup, I'd disable it after asserting the reset in of_platform_serial_remove. Other than that, Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> regards Philipp -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html