[PATCH V2 02/18] i2c: imx-lpi2c: add ipg clk for lpi2c driver

[Aisheng Dong]

> From: Clark Wang <xiaoning.wang at nxp.com>
> Sent: Tuesday, April 6, 2021 7:33 PM
> 
> The lpi2c IP needs two clks: ipg clk and per clk. The old lpi2c driver missed ipg
> clk. This patch adds ipg clk for lpi2c driver.
> 
> Signed-off-by: Gao Pan <pandy.gao at nxp.com>
> Signed-off-by: Clark Wang <xiaoning.wang at nxp.com>
> Acked-by: Fugang Duan <fugang.duan at nxp.com>

You can drop the original Ack or signed-off if there're significant changes

BTW, please move the binding doc change before this patch.

> ---
> V2 changes:
>  - Merge two clocks' prepare funtions to lpi2c_imx_clocks_prepare().
> ---
>  drivers/i2c/busses/i2c-imx-lpi2c.c | 61 +++++++++++++++++++++---------
>  1 file changed, 44 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c
> b/drivers/i2c/busses/i2c-imx-lpi2c.c
> index bbf44ac95021..89b7b0795f51 100644
> --- a/drivers/i2c/busses/i2c-imx-lpi2c.c
> +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
> @@ -94,7 +94,8 @@ enum lpi2c_imx_pincfg {
> 
>  struct lpi2c_imx_struct {
>  	struct i2c_adapter	adapter;
> -	struct clk		*clk;
> +	struct clk		*clk_per;
> +	struct clk		*clk_ipg;
>  	void __iomem		*base;
>  	__u8			*rx_buf;
>  	__u8			*tx_buf;
> @@ -207,7 +208,7 @@ static int lpi2c_imx_config(struct lpi2c_imx_struct
> *lpi2c_imx)
> 
>  	lpi2c_imx_set_mode(lpi2c_imx);
> 
> -	clk_rate = clk_get_rate(lpi2c_imx->clk);
> +	clk_rate = clk_get_rate(lpi2c_imx->clk_per);
>  	if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
>  		filt = 0;
>  	else
> @@ -538,6 +539,34 @@ static const struct of_device_id lpi2c_imx_of_match[]
> = {  };  MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
> 
> +static int lpi2c_imx_clocks_prepare(struct lpi2c_imx_struct *lpi2c_imx)
> +{
> +	int ret = 0;

Unnecessary initialization

> +
> +	ret = clk_prepare_enable(lpi2c_imx->clk_per);
> +	if (ret) {
> +		dev_err(lpi2c_imx->adapter.dev.parent,
> +				"can't enable I2C per clock, ret=%d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(lpi2c_imx->clk_ipg);
> +	if (ret) {
> +		clk_disable_unprepare(lpi2c_imx->clk_per);
> +		dev_err(lpi2c_imx->adapter.dev.parent,
> +				"can't enable I2C ipg clock, ret=%d\n", ret);
> +		return ret;
> +	}
> +
> +	return ret;

Return 0

> +}
> +
> +static void lpi2c_imx_clocks_unprepare(struct lpi2c_imx_struct
> +*lpi2c_imx) {
> +	clk_disable_unprepare(lpi2c_imx->clk_ipg);
> +	clk_disable_unprepare(lpi2c_imx->clk_per);
> +}
> +
>  static int lpi2c_imx_probe(struct platform_device *pdev)  {
>  	struct lpi2c_imx_struct *lpi2c_imx;
> @@ -563,10 +592,16 @@ static int lpi2c_imx_probe(struct platform_device
> *pdev)
>  	strlcpy(lpi2c_imx->adapter.name, pdev->name,
>  		sizeof(lpi2c_imx->adapter.name));
> 
> -	lpi2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
> -	if (IS_ERR(lpi2c_imx->clk)) {
> +	lpi2c_imx->clk_per = devm_clk_get(&pdev->dev, "per");
> +	if (IS_ERR(lpi2c_imx->clk_per)) {
>  		dev_err(&pdev->dev, "can't get I2C peripheral clock\n");
> -		return PTR_ERR(lpi2c_imx->clk);
> +		return PTR_ERR(lpi2c_imx->clk_per);
> +	}

Will this patch break imx7ulp which doesn't have per clock?

> +
> +	lpi2c_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
> +	if (IS_ERR(lpi2c_imx->clk_ipg)) {
> +		dev_err(&pdev->dev, "can't get I2C ipg clock\n");
> +		return PTR_ERR(lpi2c_imx->clk_ipg);
>  	}
> 
>  	ret = of_property_read_u32(pdev->dev.of_node,
> @@ -584,11 +619,9 @@ static int lpi2c_imx_probe(struct platform_device
> *pdev)
>  	i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
>  	platform_set_drvdata(pdev, lpi2c_imx);
> 
> -	ret = clk_prepare_enable(lpi2c_imx->clk);
> -	if (ret) {
> -		dev_err(&pdev->dev, "clk enable failed %d\n", ret);
> +	ret = lpi2c_imx_clocks_prepare(lpi2c_imx);
> +	if (ret)
>  		return ret;
> -	}
> 
>  	pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
>  	pm_runtime_use_autosuspend(&pdev->dev);
> @@ -635,7 +668,7 @@ static int __maybe_unused
> lpi2c_runtime_suspend(struct device *dev)  {
>  	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
> 
> -	clk_disable_unprepare(lpi2c_imx->clk);
> +	lpi2c_imx_clocks_unprepare(lpi2c_imx);
>  	pinctrl_pm_select_sleep_state(dev);
> 
>  	return 0;
> @@ -644,16 +677,10 @@ static int __maybe_unused
> lpi2c_runtime_suspend(struct device *dev)  static int __maybe_unused
> lpi2c_runtime_resume(struct device *dev)  {
>  	struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
> -	int ret;
> 
>  	pinctrl_pm_select_default_state(dev);
> -	ret = clk_prepare_enable(lpi2c_imx->clk);
> -	if (ret) {
> -		dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
> -		return ret;
> -	}
> 
> -	return 0;
> +	return lpi2c_imx_clocks_prepare(lpi2c_imx);
>  }
> 
>  static const struct dev_pm_ops lpi2c_pm_ops = {
> --
> 2.25.1