On Do, 2022-06-30 at 14:20 +0300, Tomer Maimon wrote:

Hi Philipp,

Thanks for your comment.

On Thu, 30 Jun 2022 at 13:59, Philipp Zabel [off-list ref] wrote:

quoted

Hi Tomer,

On Do, 2022-06-30 at 13:35 +0300, Tomer Maimon wrote:
Using syscon device tree property instead of device data to handle the
NPCM general control registers.

In case the syscon not found the code still search for nuvoton,npcm750-gcr
to support DTS backward compatibility.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
---
 drivers/reset/reset-npcm.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/reset/reset-npcm.c b/drivers/reset/reset-npcm.c
index 2ea4d3136e15..431ff2b602c5 100644
--- a/drivers/reset/reset-npcm.c
+++ b/drivers/reset/reset-npcm.c

@@ -138,8 +138,7 @@ static int npcm_reset_xlate(struct reset_controller_dev *rcdev,

 }


 static const struct of_device_id npcm_rc_match[] = {
-       { .compatible = "nuvoton,npcm750-reset",
-               .data = (void *)"nuvoton,npcm750-gcr" },
+       { .compatible = "nuvoton,npcm750-reset"},

Add a space.                                  ^^

Will modify in V7

quoted

        { }
 };

@@ -155,15 +154,15 @@ static int npcm_usb_reset(struct platform_device *pdev, struct npcm_rc_data *rc)

        u32 ipsrst1_bits = 0;
        u32 ipsrst2_bits = NPCM_IPSRST2_USB_HOST;
        u32 ipsrst3_bits = 0;
-       const char *gcr_dt;


-       gcr_dt = (const char *)
-       of_match_device(dev->driver->of_match_table, dev)->data;
-
-       gcr_regmap = syscon_regmap_lookup_by_compatible(gcr_dt);
+       gcr_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "nuvoton,sysgcr");
        if (IS_ERR(gcr_regmap)) {
-               dev_err(&pdev->dev, "Failed to find %s\n", gcr_dt);
-               return PTR_ERR(gcr_regmap);
+               dev_warn(&pdev->dev, "Failed to find nuvoton,sysgcr search for nuvoton,npcm750-gcr for Poleg backward compatibility");

Is this warning useful to the user? Maybe add suggestion like "please
update the device tree". Also there is no further message if
nuvoton,npcm750-gcr is found and all is well.

O.K.
I think about two options:

1. Modify the message "Failed to find nuvoton,sysgcr property, please
update the device tree\n Search for nuvoton,npcm750-gcr for Poleg
backward compatibility"

I would replace "Search for" with "Using"
The second line probably should be dev_info() level.

OR

2.
        if (IS_ERR(rc->gcr_regmap)) {
                dev_warn(&pdev->dev, "Failed to find nuvoton,sysgcr
please update the device tree");
                rc->gcr_regmap =
syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
                if (IS_ERR(rc->gcr_regmap)) {
                        dev_err(&pdev->dev, "Failed to find
nuvoton,npcm750-gcr");
                        return PTR_ERR(rc->gcr_regmap);
                }
                 dev_info(&pdev->dev, "found nuvoton,npcm750-gcr for
Poleg backward compatibility");
        }

The only problem that I have with option 2 is if our customers will
use the latest reset driver and they will not update their device tree
they will see all the time the dev_info message.

What do you think?

I'm fine with either. With the "please update DT" prompt it's clear how
to get rid of the warning.

regards
Philipp

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