linux-kernel - [PATCH 0/4] media: convert from clk round_rate() to determine

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Message-Id: <20250710-media-clk-round-rate-v1-0-a9617b061741@redhat.com>
Date: Thu, 10 Jul 2025 13:29:05 -0400
From: Brian Masney <bmasney@...hat.com>
To: Tomi Valkeinen <tomi.valkeinen@...asonboard.com>, 
 Mauro Carvalho Chehab <mchehab@...nel.org>, 
 Julien Massot <julien.massot@...labora.com>, 
 Maxime Ripard <mripard@...nel.org>, Stephen Boyd <sboyd@...nel.org>
Cc: linux-clk@...r.kernel.org, linux-media@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Brian Masney <bmasney@...hat.com>
Subject: [PATCH 0/4] media: convert from clk round_rate() to
 determine_rate()

The round_rate() clk ops is deprecated in the clk framework in favor
of the determine_rate() clk ops, so let's go ahead and convert the
drivers in the media subsystem using the Coccinelle semantic patch
posted below. I did a few minor cosmetic cleanups of the code in a
few cases.

Coccinelle semantic patch:

    virtual patch

    // Look up the current name of the round_rate function
    @ has_round_rate @
    identifier round_rate_name =~ ".*_round_rate";
    identifier hw_param, rate_param, parent_rate_param;
    @@

    long round_rate_name(struct clk_hw *hw_param, unsigned long rate_param,
                  unsigned long *parent_rate_param)
    {
    	...
    }

    // Rename the route_rate function name to determine_rate()
    @ script:python generate_name depends on has_round_rate @
    round_rate_name << has_round_rate.round_rate_name;
    new_name;
    @@

    coccinelle.new_name = round_rate_name.replace("_round_rate", "_determine_rate")

    // Change rate to req->rate; also change occurrences of 'return XXX'.
    @ chg_rate depends on generate_name @
    identifier has_round_rate.round_rate_name;
    identifier has_round_rate.hw_param;
    identifier has_round_rate.rate_param;
    identifier has_round_rate.parent_rate_param;
    identifier ERR =~ "E.*";
    expression E;
    @@

    long round_rate_name(struct clk_hw *hw_param, unsigned long rate_param,
                  unsigned long *parent_rate_param)
    {
    <...
    (
    -return -ERR;
    +return -ERR;
    |
    - return rate_param;
    + return 0;
    |
    - return E;
    + req->rate = E;
    +
    + return 0;
    |
    - rate_param
    + req->rate
    )
    ...>
    }

    // Coccinelle only transforms the first occurrence of the rate parameter
    // Run a second time. FIXME: Is there a better way to do this?
    @ chg_rate2 depends on generate_name @
    identifier has_round_rate.round_rate_name;
    identifier has_round_rate.hw_param;
    identifier has_round_rate.rate_param;
    identifier has_round_rate.parent_rate_param;
    @@

    long round_rate_name(struct clk_hw *hw_param, unsigned long rate_param,
                  unsigned long *parent_rate_param)
    {
    <...
    - rate_param
    + req->rate
    ...>
    }

    // Change parent_rate to req->best_parent_rate
    @ chg_parent_rate depends on generate_name @
    identifier has_round_rate.round_rate_name;
    identifier has_round_rate.hw_param;
    identifier has_round_rate.rate_param;
    identifier has_round_rate.parent_rate_param;
    @@

    long round_rate_name(struct clk_hw *hw_param, unsigned long rate_param,
                  unsigned long *parent_rate_param)
    {
    <...
    (
    - *parent_rate_param
    + req->best_parent_rate
    |
    - parent_rate_param
    + &req->best_parent_rate
    )
    ...>
    }

    // Convert the function definition from round_rate() to determine_rate()
    @ func_definition depends on chg_rate @
    identifier has_round_rate.round_rate_name;
    identifier has_round_rate.hw_param;
    identifier has_round_rate.rate_param;
    identifier has_round_rate.parent_rate_param;
    identifier generate_name.new_name;
    @@

    - long round_rate_name(struct clk_hw *hw_param, unsigned long rate_param,
    -               unsigned long *parent_rate_param)
    + int new_name(struct clk_hw *hw, struct clk_rate_request *req)
    {
        ...
    }

    // Update the ops from round_rate() to determine_rate()
    @ ops depends on func_definition @
    identifier has_round_rate.round_rate_name;
    identifier generate_name.new_name;
    @@

    {
        ...,
    -   .round_rate = round_rate_name,
    +   .determine_rate = new_name,
        ...,
    }

Note that I used coccinelle 1.2 instead of 1.3 since the newer version
adds unnecessary braces as described in this post.
https://lore.kernel.org/cocci/67642477-5f3e-4b2a-914d-579a54f48cbd@intel.com/

Signed-off-by: Brian Masney <bmasney@...hat.com>
---
Brian Masney (4):
      media: i2c: ds90ub953: convert from round_rate() to determine_rate()
      media: i2c: max96717: convert from round_rate() to determine_rate()
      media: i2c: tc358746: convert from round_rate() to determine_rate()
      media: platform: ti: omap3isp: isp: convert from round_rate() to determine_rate()

 drivers/media/i2c/ds90ub953.c            | 12 +++++++-----
 drivers/media/i2c/max96717.c             | 16 +++++++++-------
 drivers/media/i2c/tc358746.c             | 12 +++++++-----
 drivers/media/platform/ti/omap3isp/isp.c | 10 +++++-----
 4 files changed, 28 insertions(+), 22 deletions(-)
---
base-commit: b551c4e2a98a177a06148cf16505643cd2108386
change-id: 20250710-media-clk-round-rate-50fa3894747b

Best regards,
-- 
Brian Masney <bmasney@...hat.com>