Re: [PATCH] i2c: designware: Fix bogus sda_hold_time due to uninitialized vars

From: Ard Biesheuvel
Date: Mon May 22 2017 - 02:02:41 EST




> On 22 May 2017, at 07:46, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:
>
> We need to initializes those variables to 0 for platforms that do not
> provide ACPI parameters. Otherwise, we set sda_hold_time to random
> values, breaking e.g. Galileo and IOT2000 boards.
>
> Fixes: 9d6408433019 ("i2c: designware: don't infer timings described by ACPI from clock rate")
> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

> ---
>
> Affects 4.12-rc2.
>
> drivers/i2c/busses/i2c-designware-platdrv.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
> index 6283b99d2b17..d1263b82d646 100644
> --- a/drivers/i2c/busses/i2c-designware-platdrv.c
> +++ b/drivers/i2c/busses/i2c-designware-platdrv.c
> @@ -94,9 +94,9 @@ static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
> static int dw_i2c_acpi_configure(struct platform_device *pdev)
> {
> struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
> + u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0;
> acpi_handle handle = ACPI_HANDLE(&pdev->dev);
> const struct acpi_device_id *id;
> - u32 ss_ht, fp_ht, hs_ht, fs_ht;
> struct acpi_device *adev;
> const char *uid;
>