[PATCH 2/3] reset: mchp: sparx5: add switch reset driver
Andrew Lunn
andrew at lunn.ch
Wed Jan 13 18:23:49 EST 2021
> +static int sparx5_switch_reset(struct reset_controller_dev *rcdev,
> + unsigned long id)
> +{
> + struct mchp_reset_context *ctx =
> + container_of(rcdev, struct mchp_reset_context, reset_ctrl);
> + u32 val;
> +
> + /* Make sure the core is PROTECTED from reset */
> + regmap_update_bits(ctx->cpu_ctrl, PROTECT_REG, PROTECT_BIT, PROTECT_BIT);
> +
> + dev_info(ctx->dev, "soft reset of switchcore\n");
dev_dbg()?
> +
> + /* Start soft reset */
> + regmap_write(ctx->gcb_ctrl, SOFT_RESET_REG, SOFT_RESET_BIT);
> +
> + /* Wait for soft reset done */
> + return read_poll_timeout(sparx5_read_soft_rst, val,
> + (val & SOFT_RESET_BIT) == 0,
> + 1, 100, false,
> + ctx);
> +}
> +static int mchp_sparx5_reset_config(struct platform_device *pdev,
> + struct mchp_reset_context *ctx)
> +{
> + struct device_node *dn = pdev->dev.of_node;
> + struct regmap *cpu_ctrl, *gcb_ctrl;
> + struct device_node *syscon_np;
> + int err;
> +
> + syscon_np = of_parse_phandle(dn, "syscons", 0);
> + if (!syscon_np)
> + return -ENODEV;
> + cpu_ctrl = syscon_node_to_regmap(syscon_np);
> + if (IS_ERR(cpu_ctrl))
> + goto err_cpu;
> + of_node_put(syscon_np);
> +
> + syscon_np = of_parse_phandle(dn, "syscons", 1);
> + if (!syscon_np)
> + return -ENODEV;
> + gcb_ctrl = syscon_node_to_regmap(syscon_np);
> + if (IS_ERR(gcb_ctrl))
> + goto err_gcb;
> + of_node_put(syscon_np);
> +
> + ctx->cpu_ctrl = cpu_ctrl;
> + ctx->gcb_ctrl = gcb_ctrl;
> +
> + ctx->reset_ctrl.owner = THIS_MODULE;
> + ctx->reset_ctrl.nr_resets = 1;
> + ctx->reset_ctrl.ops = &sparx5_reset_ops;
> + ctx->reset_ctrl.of_node = dn;
> +
> + err = devm_reset_controller_register(&pdev->dev, &ctx->reset_ctrl);
> + if (err)
> + dev_err(&pdev->dev, "could not register reset controller\n");
> + pr_info("%s:%d\n", __func__, __LINE__);
> + return err;
> +err_cpu:
> + of_node_put(syscon_np);
> + dev_err(&pdev->dev, "No cpu syscon map\n");
> + return PTR_ERR(cpu_ctrl);
> +err_gcb:
> + of_node_put(syscon_np);
> + dev_err(&pdev->dev, "No gcb syscon map\n");
> + return PTR_ERR(gcb_ctrl);
It would be normal to put the dev_err() before the goto, set err =
PTR_ERR() and then goto out;
> +}
> +
> +static int mchp_sparx5_reset_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct mchp_reset_context *ctx;
> +
> + pr_info("%s:%d\n", __func__, __LINE__);
More left over debug.
> + ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> + if (!ctx)
> + return -ENOMEM;
> + ctx->dev = dev;
> + return mchp_sparx5_reset_config(pdev, ctx);
> +}
> +
> +static const struct of_device_id mchp_sparx5_reset_of_match[] = {
> + {
> + .compatible = "microchip,sparx5-switch-reset",
> + },
> + { /*sentinel*/ }
> +};
> +static int __init mchp_sparx5_reset_init(void)
> +{
> + return platform_driver_register(&mchp_sparx5_reset_driver);
> +}
> +
> +postcore_initcall(mchp_sparx5_reset_init);
Does it actually need to be postcore? The users of the reset should
look for -EPROBE_DEFER and try again later. And this then becomes just
a normal driver.
Andrew
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