linux-kernel - Re: [PATCH v2 1/4] i3c: renesas: Switch to clk_bulk API and store clocks in private data

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Message-ID: <aVPzQrFL7T5KP1jI@lizhi-Precision-Tower-5810>
Date: Tue, 30 Dec 2025 10:44:02 -0500
From: Frank Li <Frank.li@....com>
To: Tommaso Merciai <tommaso.merciai.xr@...renesas.com>
Cc: tomm.merciai@...il.com, linux-renesas-soc@...r.kernel.org,
	biju.das.jz@...renesas.com,
	Wolfram Sang <wsa+renesas@...g-engineering.com>,
	Alexandre Belloni <alexandre.belloni@...tlin.com>,
	Philipp Zabel <p.zabel@...gutronix.de>,
	linux-i3c@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 1/4] i3c: renesas: Switch to clk_bulk API and store
 clocks in private data

On Tue, Dec 30, 2025 at 11:39:36AM +0100, Tommaso Merciai wrote:
> Replace individual devm_clk_get_enabled() calls with the clk_bulk API
> and store the clock handles in the driver's private data structure.
>
> This simplifies the code, and prepares the driver for upcoming
> suspend/resume support.
>
> No functional change intended.
>
> Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@...renesas.com>
> ---
> v1->v2:
>  - New patch.
>
>  drivers/i3c/master/renesas-i3c.c | 42 +++++++++++++++++++++-----------
>  1 file changed, 28 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
> index 426a418f29b6..8ef6ff06df90 100644
> --- a/drivers/i3c/master/renesas-i3c.c
> +++ b/drivers/i3c/master/renesas-i3c.c
> @@ -259,7 +259,8 @@ struct renesas_i3c {
>  	u8 addrs[RENESAS_I3C_MAX_DEVS];
>  	struct renesas_i3c_xferqueue xferqueue;
>  	void __iomem *regs;
> -	struct clk *tclk;
> +	struct clk_bulk_data clks[3];
> +	u8 num_clks;
>  };
>
>  struct renesas_i3c_i2c_dev_data {
> @@ -276,6 +277,10 @@ struct renesas_i3c_config {
>  	unsigned int has_pclkrw:1;
>  };
>
> +static const char * const renesas_i3c_clks[] = {
> +	"pclk", "tclk", "pclkrw"
> +};
> +
>  static inline void renesas_i3c_reg_update(void __iomem *reg, u32 mask, u32 val)
>  {
>  	u32 data = readl(reg);
> @@ -489,7 +494,7 @@ static int renesas_i3c_bus_init(struct i3c_master_controller *m)
>  	int od_high_ticks, od_low_ticks, i2c_total_ticks;
>  	int ret;
>
> -	rate = clk_get_rate(i3c->tclk);
> +	rate = clk_get_rate(i3c->clks[1].clk);

Can you use macro of variable replace hardcode "1"

>  	if (!rate)
>  		return -EINVAL;
>
> @@ -1298,11 +1303,17 @@ static const struct renesas_i3c_irq_desc renesas_i3c_irqs[] = {
>  	{ .name = "nack", .isr = renesas_i3c_tend_isr, .desc = "i3c-nack" },
>  };
>
> +static void renesas_i3c_clk_bulk_disable_unprepare(void *data)
> +{
> +	struct renesas_i3c *i3c = data;
> +
> +	clk_bulk_disable_unprepare(i3c->num_clks, i3c->clks);
> +}
> +
>  static int renesas_i3c_probe(struct platform_device *pdev)
>  {
>  	struct renesas_i3c *i3c;
>  	struct reset_control *reset;
> -	struct clk *clk;
>  	const struct renesas_i3c_config *config = of_device_get_match_data(&pdev->dev);
>  	int ret, i;
>
> @@ -1317,19 +1328,22 @@ static int renesas_i3c_probe(struct platform_device *pdev)
>  	if (IS_ERR(i3c->regs))
>  		return PTR_ERR(i3c->regs);
>
> -	clk = devm_clk_get_enabled(&pdev->dev, "pclk");
> -	if (IS_ERR(clk))
> -		return PTR_ERR(clk);
> +	i3c->num_clks = config->has_pclkrw ? 3 : 2;
>
> -	if (config->has_pclkrw) {
> -		clk = devm_clk_get_enabled(&pdev->dev, "pclkrw");
> -		if (IS_ERR(clk))
> -			return PTR_ERR(clk);
> -	}
> +	for (i = 0; i < i3c->num_clks; i++)
> +		i3c->clks[i].id = renesas_i3c_clks[i];
>
> -	i3c->tclk = devm_clk_get_enabled(&pdev->dev, "tclk");
> -	if (IS_ERR(i3c->tclk))
> -		return PTR_ERR(i3c->tclk);
> +	ret = devm_clk_bulk_get(&pdev->dev, i3c->num_clks, i3c->clks);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_bulk_prepare_enable(i3c->num_clks, i3c->clks);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_add_action_or_reset(&pdev->dev, renesas_i3c_clk_bulk_disable_unprepare, i3c);
> +	if (ret)
> +		return ret;

Can you use devm_clk_bulk_get_all_enabled()? all dts already verified
by dt-schema.

Frank

>
>  	reset = devm_reset_control_get_optional_exclusive_deasserted(&pdev->dev, "tresetn");
>  	if (IS_ERR(reset))
> --
> 2.43.0
>