On 1 October 2018 at 13:49, Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx> wrote:
> There are platforms which don't provide input clock rate but provide
> I2C timing parameters. Commit 3bd4f277274b ("i2c: designware: Call
> i2c_dw_clk_rate() only once in i2c_dw_init_master()") causes needless
> warning during probe on those platforms since i2c_dw_clk_rate(), which
> causes the warning when input clock is unknown, is called even when
> there is no need to calculate timing parameters.
>
> Fixes: 3bd4f277274b ("i2c: designware: Call i2c_dw_clk_rate() only once in i2c_dw_init_master()")
> Reported-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # 4.19
> Signed-off-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
Tested-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Thanks!
> ---
> for current 4.19-rc6. I Cc'ed stable just in case this doesn't hit the
> v4.19.
> ---
> drivers/i2c/busses/i2c-designware-master.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
> index 94d94b4a9a0d..18cc324f3ca9 100644
> --- a/drivers/i2c/busses/i2c-designware-master.c
> +++ b/drivers/i2c/busses/i2c-designware-master.c
> @@ -34,11 +34,11 @@ static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
>
> static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
> {
> - u32 ic_clk = i2c_dw_clk_rate(dev);
> const char *mode_str, *fp_str = "";
> u32 comp_param1;
> u32 sda_falling_time, scl_falling_time;
> struct i2c_timings *t = &dev->timings;
> + u32 ic_clk;
> int ret;
>
> ret = i2c_dw_acquire_lock(dev);
> @@ -53,6 +53,7 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
>
> /* Calculate SCL timing parameters for standard mode if not set */
> if (!dev->ss_hcnt || !dev->ss_lcnt) {
> + ic_clk = i2c_dw_clk_rate(dev);
> dev->ss_hcnt =
> i2c_dw_scl_hcnt(ic_clk,
> 4000, /* tHD;STA = tHIGH = 4.0 us */
> @@ -89,6 +90,7 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
> * needed also in high speed mode.
> */
> if (!dev->fs_hcnt || !dev->fs_lcnt) {
> + ic_clk = i2c_dw_clk_rate(dev);
> dev->fs_hcnt =
> i2c_dw_scl_hcnt(ic_clk,
> 600, /* tHD;STA = tHIGH = 0.6 us */
> --
> 2.19.0
>
