[PATCH v2 2/2] clk: hi6220: initialize UART1 clock to 150MHz
Michael Turquette
mturquette at baylibre.com
Wed Jul 6 14:43:11 PDT 2016
Quoting Guodong Xu (2016-06-29 01:45:55)
> From: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz at linaro.org>
>
> Early at boot, during the sys_clk initialization, make sure UART1 uses
> the higher frequency clock, 150MHz.
>
> This enables support for higher baud rates (up to 3Mbps) in UART1, which
> is required by faster bluetooth transfers.
>
> v2: use clk_set_rate() to propergate clock settings.
>
> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz at linaro.org>
> Signed-off-by: Guodong Xu <guodong.xu at linaro.org>
> ---
> drivers/clk/hisilicon/clk-hi6220.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/clk/hisilicon/clk-hi6220.c b/drivers/clk/hisilicon/clk-hi6220.c
> index a36ffcb..631c56f 100644
> --- a/drivers/clk/hisilicon/clk-hi6220.c
> +++ b/drivers/clk/hisilicon/clk-hi6220.c
> @@ -12,6 +12,7 @@
>
> #include <linux/kernel.h>
> #include <linux/clk-provider.h>
> +#include <linux/clk.h>
> #include <linux/clkdev.h>
> #include <linux/io.h>
> #include <linux/of.h>
> @@ -192,6 +193,9 @@ static void __init hi6220_clk_sys_init(struct device_node *np)
>
> hi6220_clk_register_divider(hi6220_div_clks_sys,
> ARRAY_SIZE(hi6220_div_clks_sys), clk_data);
> +
> + if (clk_set_rate(clk_data->clk_data.clks[HI6220_UART1_SRC], 150000000))
> + pr_err("failed to set uart1 clock rate\n");
Why doesn't the UART driver call clk_get and then clk_set_rate on this
clock? Why do it in the clk provider driver?
Thanks,
Mike
> }
> CLK_OF_DECLARE(hi6220_clk_sys, "hisilicon,hi6220-sysctrl", hi6220_clk_sys_init);
>
> --
> 1.9.1
>
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