Commit 3d1fa055 authored Jul 23, 2021 by Andy Shevchenko Committed by Greg Kroah-Hartman Jul 27, 2021

serial: max310x: Use clock-names property matching to recognize EXTCLK

Dennis reported that on ACPI-based systems the clock frequency
isn't enough to configure device properly. We have to respect
the clock source as well. To achieve this match the clock-names
property against "osc" to recognize external clock connection.
On DT-based system this doesn't change anything.

Reported-and-tested-by: Dennis Giaya <dgiaya@whoi.edu>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210723125943.22039-1-andriy.shevchenko@linux.intel.com

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 0a9410b9

drivers/tty/serial/max310x.c

+5 −10

Original line number	Diff line number	Diff line
		@@ -1271,19 +1271,14 @@ static int max310x_probe(struct device dev, const struct max310x_devtype devty
		/* Always ask for fixed clock rate from a property. */
		device_property_read_u32(dev, "clock-frequency", &uartclk);

		s->clk = devm_clk_get_optional(dev, "osc");
		if (IS_ERR(s->clk))
		return PTR_ERR(s->clk);
		if (s->clk) {
		xtal = false;
		} else {
		xtal = device_property_match_string(dev, "clock-names", "osc") < 0;
		if (xtal)
		s->clk = devm_clk_get_optional(dev, "xtal");
		else
		s->clk = devm_clk_get_optional(dev, "osc");
		if (IS_ERR(s->clk))
		return PTR_ERR(s->clk);

		xtal = true;
		}

		ret = clk_prepare_enable(s->clk);
		if (ret)
		return ret;