Re: [PATCH v2 2/2] memory: mtk-smi: mt8188: Add SMI clamp function

[Krzysztof Kozlowski <krzk@kernel.org>]

On 20/11/2024 07:36, Friday Yang wrote:
> In order to avoid handling glitch signal when MTCMOS on/off, SMI need
> clamp and reset operation. Parse power reset settings for LARBs which
> need to reset. Register genpd callback for SMI LARBs and apply reset
> operations in the callback.
> 
> Signed-off-by: Friday Yang <friday.yang@mediatek.com>
> ---
>  drivers/memory/mtk-smi.c | 175 ++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 171 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
> index 2bc034dff691..c7119f655350 100644
> --- a/drivers/memory/mtk-smi.c
> +++ b/drivers/memory/mtk-smi.c
> @@ -10,15 +10,21 @@
>  #include <linux/err.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
> +#include <linux/mfd/syscon.h>

Where do you use it?

>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/of_platform.h>
>  #include <linux/platform_device.h>
> +#include <linux/pm_domain.h>

Where do you use it?

>  #include <linux/pm_runtime.h>
> +#include <linux/regmap.h>

Where do you use it?

> +#include <linux/reset.h>
> +#include <linux/reset-controller.h>
>  #include <linux/soc/mediatek/mtk_sip_svc.h>
>  #include <soc/mediatek/smi.h>
>  #include <dt-bindings/memory/mt2701-larb-port.h>
>  #include <dt-bindings/memory/mtk-memory-port.h>
> +#include <dt-bindings/reset/mt8188-resets.h>
>  

...

>  
> +static int mtk_smi_larb_parse_clamp_info(struct mtk_smi_larb *larb)
> +{
> +	struct device *dev = larb->dev;
> +	const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
> +	struct device_node *smi_node;
> +	struct of_phandle_args args;
> +	int ret, index;
> +
> +	/* Only SMI LARBs located in camera and image subsys need to

Use Linux coding style.

> +	 * apply clamp and reset operation, others can be skipped.
> +	 */
> +	ret = of_parse_phandle_with_fixed_args(dev->of_node,
> +					       "resets", 1, 0, &args);

NAK

> +	if (ret)
> +		return 0;
> +
> +	smi_node = of_parse_phandle(dev->of_node, "mediatek,smi", 0);
> +	if (!smi_node)
> +		return -EINVAL;
> +
> +	index = args.args[0];

That's reset, not clamp port. NAK.

> +	larb->sub_comm_inport = larb_gen->clamp_port[index];
> +	larb->sub_comm_syscon = device_node_to_regmap(smi_node);
> +	of_node_put(smi_node);
> +
> +	if (IS_ERR(larb->sub_comm_syscon) ||
> +	    larb->sub_comm_inport >= SMI_SUB_COMM_INPORT_NR) {
> +		larb->sub_comm_syscon = NULL;
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int mtk_smi_larb_parse_reset_info(struct mtk_smi_larb *larb)
> +{
> +	struct device *dev = larb->dev;
> +	int ret;
> +
> +	/* Only SMI LARBs located in camera and image subsys need to

Use Linux coding style. This applies to all your patches and all places
in this patch.

> +	 * apply clamp and reset operation, others can be skipped.
> +	 */
> +	if (!of_find_property(dev->of_node, "resets", NULL))

That's not how you use reset framework API. Use proper optional API.

> +		return 0;
> +
> +	larb->rst_con = devm_reset_control_get(dev, "larb");
> +	if (IS_ERR(larb->rst_con))
> +		return dev_err_probe(dev, PTR_ERR(larb->rst_con),
> +				     "Can not get larb reset controller\n");
> +
> +	larb->nb.notifier_call = mtk_smi_genpd_callback;
> +	ret = dev_pm_genpd_add_notifier(dev, &larb->nb);
> +	if (ret) {
> +		dev_err(dev, "Failed to add genpd callback %d\n", ret);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  static int mtk_smi_larb_probe(struct platform_device *pdev)
>  {
>  	struct mtk_smi_larb *larb;
> @@ -538,6 +685,7 @@ static int mtk_smi_larb_probe(struct platform_device *pdev)
>  	if (!larb)
>  		return -ENOMEM;
>  
> +	larb->dev = dev;
>  	larb->larb_gen = of_device_get_match_data(dev);
>  	larb->base = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(larb->base))
> @@ -554,15 +702,29 @@ static int mtk_smi_larb_probe(struct platform_device *pdev)
>  	if (ret < 0)
>  		return ret;
>  
> -	pm_runtime_enable(dev);
> +	/* find sub common to clamp larb for ISP software reset */
> +	ret = mtk_smi_larb_parse_clamp_info(larb);
> +	if (ret) {
> +		dev_err(dev, "Failed to get clamp setting for larb\n");
> +		goto err_link_remove;
> +	}
> +
> +	ret = mtk_smi_larb_parse_reset_info(larb);
> +	if (ret) {
> +		dev_err(dev, "Failed to get power setting for larb\n");
> +		goto err_link_remove;
> +	}
> +
>  	platform_set_drvdata(pdev, larb);
>  	ret = component_add(dev, &mtk_smi_larb_component_ops);
>  	if (ret)
> -		goto err_pm_disable;
> +		goto err_link_remove;
> +
> +	pm_runtime_enable(dev);
> +
>  	return 0;
>  
> -err_pm_disable:
> -	pm_runtime_disable(dev);
> +err_link_remove:
>  	device_link_remove(dev, larb->smi_common_dev);
>  	return ret;
>  }
> @@ -686,6 +848,10 @@ static const struct mtk_smi_common_plat mtk_smi_common_mt8188_vpp = {
>  	.init     = mtk_smi_common_mt8195_init,
>  };
>  
> +static const struct mtk_smi_common_plat mtk_smi_sub_common_mt8188 = {
> +	.type     = MTK_SMI_GEN2_SUB_COMM,
> +};
> +
>  static const struct mtk_smi_common_plat mtk_smi_common_mt8192 = {
>  	.type     = MTK_SMI_GEN2,
>  	.has_gals = true,
> @@ -729,6 +895,7 @@ static const struct of_device_id mtk_smi_common_of_ids[] = {
>  	{.compatible = "mediatek,mt8186-smi-common", .data = &mtk_smi_common_mt8186},
>  	{.compatible = "mediatek,mt8188-smi-common-vdo", .data = &mtk_smi_common_mt8188_vdo},
>  	{.compatible = "mediatek,mt8188-smi-common-vpp", .data = &mtk_smi_common_mt8188_vpp},
> +	{.compatible = "mediatek,mt8188-smi-sub-common", .data = &mtk_smi_sub_common_mt8188},
>  	{.compatible = "mediatek,mt8192-smi-common", .data = &mtk_smi_common_mt8192},
>  	{.compatible = "mediatek,mt8195-smi-common-vdo", .data = &mtk_smi_common_mt8195_vdo},
>  	{.compatible = "mediatek,mt8195-smi-common-vpp", .data = &mtk_smi_common_mt8195_vpp},


Best regards,
Krzysztof