From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> [ Upstream commit 3d1fa055ea7298345795b982de7a5b9ec6ae238d ] 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@xxxxxxxx> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210723125943.22039-1-andriy.shevchenko@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/tty/serial/max310x.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index ef11860cd69e..3df0788ddeb0 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -1271,18 +1271,13 @@ 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"); + 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); - if (s->clk) { - xtal = false; - } else { - s->clk = devm_clk_get_optional(dev, "xtal"); - if (IS_ERR(s->clk)) - return PTR_ERR(s->clk); - - xtal = true; - } ret = clk_prepare_enable(s->clk); if (ret) -- 2.30.2
