Re: [PATCH v2 3/6] clk: qcom: branch: Add BRANCH_HALT_INVERT flag support for branch clocks

[Stephen Boyd <sboyd@kernel.org>]

Quoting Melody Olvera (2022-10-14 15:10:08)
> diff --git a/drivers/clk/qcom/clk-branch.c b/drivers/clk/qcom/clk-branch.c
> index f869fc6aaed6..b5dc1f4ef277 100644
> --- a/drivers/clk/qcom/clk-branch.c
> +++ b/drivers/clk/qcom/clk-branch.c
> @@ -1,6 +1,7 @@
>  // SPDX-License-Identifier: GPL-2.0
>  /*
>   * Copyright (c) 2013, The Linux Foundation. All rights reserved.
> + * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
>   */
>  
>  #include <linux/kernel.h>
> @@ -56,6 +57,10 @@ static bool clk_branch2_check_halt(const struct clk_branch *br, bool enabling)
>  
>         if (enabling) {
>                 val &= mask;
> +
> +               if (br->halt_check == BRANCH_HALT_INVERT)
> +                       return (val & BRANCH_CLK_OFF) == BRANCH_CLK_OFF;
> +
>                 return (val & BRANCH_CLK_OFF) == 0 ||
>                         val == BRANCH_NOC_FSM_STATUS_ON;
>         } else {
> diff --git a/drivers/clk/qcom/clk-branch.h b/drivers/clk/qcom/clk-branch.h
> index 17a58119165e..4ac1debeb91e 100644
> --- a/drivers/clk/qcom/clk-branch.h
> +++ b/drivers/clk/qcom/clk-branch.h
> @@ -1,5 +1,6 @@
>  /* SPDX-License-Identifier: GPL-2.0 */
>  /* Copyright (c) 2013, The Linux Foundation. All rights reserved. */
> +/* Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved. */
>  
>  #ifndef __QCOM_CLK_BRANCH_H__
>  #define __QCOM_CLK_BRANCH_H__
> @@ -33,6 +34,7 @@ struct clk_branch {
>  #define BRANCH_HALT_ENABLE_VOTED       (BRANCH_HALT_ENABLE | BRANCH_VOTED)
>  #define BRANCH_HALT_DELAY              2 /* No bit to check; just delay */
>  #define BRANCH_HALT_SKIP               3 /* Don't check halt bit */
> +#define BRANCH_HALT_INVERT             4 /* Invert logic for halt bit */

How is it different from BRANCH_HALT vs. BRANCH_HALT_ENABLE?