[PATCH] tty: serial: samsung: Correct clock selection logic
From: Jonathan Bakker <hidden>
Date: 2020-05-09 01:34:49
Also in:
linux-samsung-soc, linux-serial, lkml
Subsystem:
arm/samsung s3c, s5p and exynos arm architectures, the rest, tty layer and serial drivers · Maintainers:
Krzysztof Kozlowski, Peter Griffin, Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
Some variants of the samsung tty driver can pick which clock to use for their baud rate generation. In the DT conversion, a default clock was selected to be used if a specific one wasn't assigned and then a comparison of which clock rate worked better was done. Unfortunately, the comparison was implemented in such a way that only the default clock was ever actually compared. Fix this by iterating through all possible clocks, except when a specific clock has already been picked via clk_sel (which is only possible via board files). Signed-off-by: Jonathan Bakker <redacted> --- drivers/tty/serial/samsung_tty.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 73f951d65b93..9d2b4be44209 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c@@ -1281,14 +1281,14 @@ static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport, struct s3c24xx_uart_info *info = ourport->info; struct clk *clk; unsigned long rate; - unsigned int cnt, baud, quot, clk_sel, best_quot = 0; + unsigned int cnt, baud, quot, best_quot = 0; char clkname[MAX_CLK_NAME_LENGTH]; int calc_deviation, deviation = (1 << 30) - 1; - clk_sel = (ourport->cfg->clk_sel) ? ourport->cfg->clk_sel : - ourport->info->def_clk_sel; for (cnt = 0; cnt < info->num_clks; cnt++) { - if (!(clk_sel & (1 << cnt))) + /* Keep selected clock if provided */ + if (ourport->cfg->clk_sel && + !(ourport->cfg->clk_sel & (1 << cnt))) continue; sprintf(clkname, "clk_uart_baud%d", cnt);
--
2.20.1
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