serial: max310x: fail probe if clock crystal is unstable

A stable clock is really required in order to use this UART, so log an
error message and bail out if the chip reports that the clock is not
stable.

Fixes: 4cf9a888fd ("serial: max310x: Check the clock readiness")
Cc: stable@vger.kernel.org
Suggested-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Link: https://www.spinics.net/lists/linux-serial/msg35773.html
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240116213001.3691629-4-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hugo Villeneuve 2024-01-16 16:30:00 -05:00 committed by Greg Kroah-Hartman
parent 93cd256ab2
commit 8afa6c6dec

View File

@ -587,7 +587,7 @@ static int max310x_update_best_err(unsigned long f, long *besterr)
return 1;
}
static u32 max310x_set_ref_clk(struct device *dev, struct max310x_port *s,
static s32 max310x_set_ref_clk(struct device *dev, struct max310x_port *s,
unsigned long freq, bool xtal)
{
unsigned int div, clksrc, pllcfg = 0;
@ -657,7 +657,8 @@ static u32 max310x_set_ref_clk(struct device *dev, struct max310x_port *s,
} while (!stable && (++try < MAX310X_XTAL_WAIT_RETRIES));
if (!stable)
dev_warn(dev, "clock is not stable yet\n");
return dev_err_probe(dev, -EAGAIN,
"clock is not stable\n");
}
return bestfreq;
@ -1282,7 +1283,7 @@ static int max310x_probe(struct device *dev, const struct max310x_devtype *devty
{
int i, ret, fmin, fmax, freq;
struct max310x_port *s;
u32 uartclk = 0;
s32 uartclk = 0;
bool xtal;
for (i = 0; i < devtype->nr; i++)
@ -1360,6 +1361,11 @@ static int max310x_probe(struct device *dev, const struct max310x_devtype *devty
}
uartclk = max310x_set_ref_clk(dev, s, freq, xtal);
if (uartclk < 0) {
ret = uartclk;
goto out_uart;
}
dev_dbg(dev, "Reference clock set to %i Hz\n", uartclk);
for (i = 0; i < devtype->nr; i++) {