Re: [PATCH 14/17] i3c: mipi-i3c-hci: Factor out software reset into helper

Frank Li
2025-12-19T16:49:21Z

On Fri, Dec 19, 2025 at 04:45:31PM +0200, Adrian Hunter wrote:
> Prepare for future reuse of the reset sequence in other contexts, such as
> power management. Move the software reset logic from i3c_hci_init() into a
> dedicated helper function, i3c_hci_software_reset().

Add sentense about add error message when timeout happen.

Frank

>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
> drivers/i3c/master/mipi-i3c-hci/core.c | 41 ++++++++++++++++++--------
> 1 file changed, 29 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
> index c4b249fde764..3b0609cb7da7 100644
> --- a/drivers/i3c/master/mipi-i3c-hci/core.c
> +++ b/drivers/i3c/master/mipi-i3c-hci/core.c
> @@ -585,6 +585,34 @@ static irqreturn_t i3c_hci_irq_handler(int irq, void *dev_id)
> return result;
> }
>
> +static int i3c_hci_software_reset(struct i3c_hci *hci)
> +{
> + u32 regval;
> + int ret;
> +
> + /*
> + * SOFT_RST must be clear before we write to it.
> + * Then we must wait until it clears again.
> + */
> + ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
> + !(regval & SOFT_RST), 0, 10 * USEC_PER_MSEC);
> + if (ret) {
> + dev_err(&hci->master.dev, "%s: Software reset stuck\n", __func__);
> + return ret;
> + }
> +
> + reg_write(RESET_CONTROL, SOFT_RST);
> +
> + ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
> + !(regval & SOFT_RST), 0, 10 * USEC_PER_MSEC);
> + if (ret) {
> + dev_err(&hci->master.dev, "%s: Software reset failed\n", __func__);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static int i3c_hci_init(struct i3c_hci *hci)
> {
> bool size_in_dwords, mode_selector;
> @@ -654,18 +682,7 @@ static int i3c_hci_init(struct i3c_hci *hci)
> if (ret)
> return ret;
>
> - /*
> - * Now let's reset the hardware.
> - * SOFT_RST must be clear before we write to it.
> - * Then we must wait until it clears again.
> - */
> - ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
> - !(regval & SOFT_RST), 1, 10000);
> - if (ret)
> - return -ENXIO;
> - reg_write(RESET_CONTROL, SOFT_RST);
> - ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
> - !(regval & SOFT_RST), 1, 10000);
> + ret = i3c_hci_software_reset(hci);
> if (ret)
> return -ENXIO;
>
> --
> 2.51.0
>
>
> --
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