Re: [PATCH 2/2] i2c: Add Spreadtrum I2C controller driver

From: Andy Shevchenko
Date: Sat Jun 17 2017 - 13:19:11 EST


On Thu, Jun 15, 2017 at 2:30 PM, Baolin Wang <baolin.wang@xxxxxxxxxxxxxx> wrote:
> This patch adds the I2C controller driver for Spreadtrum platform.


> + i2c_dev->irq = platform_get_irq(pdev, 0);
> + if (i2c_dev->irq < 0) {
> + dev_err(&pdev->dev, "failed to get irq resource\n");

> + return -ENXIO;

Why shadow actual error?

> + }


> + if (!of_property_read_u32(dev->of_node, "clock-frequency", &prop))
> + i2c_dev->bus_freq = prop;
> +
> + sprd_i2c_clk_init(i2c_dev);
> + platform_set_drvdata(pdev, i2c_dev);
> +
> + pm_runtime_set_autosuspend_delay(i2c_dev->dev, SPRD_I2C_PM_TIMEOUT);
> + pm_runtime_use_autosuspend(i2c_dev->dev);
> + pm_runtime_set_active(i2c_dev->dev);
> + pm_runtime_enable(i2c_dev->dev);
> +
> + ret = pm_runtime_get_sync(i2c_dev->dev);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "i2c%d pm runtime resume failed!\n",
> + pdev->id);

> + return ret;

goto error;

> + }
> +
> + ret = devm_request_threaded_irq(dev, i2c_dev->irq,
> + sprd_i2c_isr, sprd_i2c_isr_thread,
> + IRQF_NO_SUSPEND | IRQF_ONESHOT,
> + pdev->name, i2c_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to request irq %d\n", i2c_dev->irq);
> + goto error;
> + }
> +
> + ret = i2c_add_numbered_adapter(&i2c_dev->adap);
> + if (ret) {
> + dev_err(&pdev->dev, "add adapter failed\n");
> + goto error;
> + }
> +
> + pm_runtime_mark_last_busy(i2c_dev->dev);
> + pm_runtime_put_autosuspend(i2c_dev->dev);
> + return 0;
> +
> +error:
> + pm_runtime_put_noidle(i2c_dev->dev);
> + pm_runtime_disable(i2c_dev->dev);
> + return ret;
> +}
> +
> +static int sprd_i2c_remove(struct platform_device *pdev)
> +{
> + struct sprd_i2c *i2c_dev = platform_get_drvdata(pdev);
> + int ret;
> +

> + ret = pm_runtime_get_sync(i2c_dev->dev);
> + if (ret < 0)
> + return ret;

Does it make any sense? Doesn't device core power on the device before
calling ->remove() ?

> +
> + i2c_del_adapter(&i2c_dev->adap);
> +
> + if (!IS_ERR_OR_NULL(i2c_dev->clk))

_OR_NULL looks suspicious.

> + clk_unprepare(i2c_dev->clk);
> +
> + pm_runtime_put_noidle(i2c_dev->dev);
> + pm_runtime_disable(i2c_dev->dev);
> +
> + return 0;
> +}
> +

> +#ifdef CONFIG_PM_SLEEP

__maybe_unused instead?

> +static int sprd_i2c_suspend_noirq(struct device *pdev)

> +static int sprd_i2c_resume_noirq(struct device *pdev)

> +#endif /* CONFIG_PM_SLEEP */

> +#ifdef CONFIG_PM

Ditto.

> +static int sprd_i2c_runtime_suspend(struct device *pdev)

> +}

> +static int sprd_i2c_runtime_resume(struct device *pdev)
> +{

> + clk_prepare_enable(i2c_dev->clk);

This might fail.


> +}
> +#endif /* CONFIG_PM */


> +static struct platform_driver sprd_i2c_driver = {
> + .probe = sprd_i2c_probe,
> + .remove = sprd_i2c_remove,
> + .driver = {
> + .name = "sprd-i2c",

> + .of_match_table = of_match_ptr(sprd_i2c_of_match),

of_match_ptr seems redundant.

> + .pm = &sprd_i2c_pm_ops,
> + },
> +};
> +

> +static int __init sprd_i2c_init(void)
> +{
> + return platform_driver_register(&sprd_i2c_driver);
> +}

> +arch_initcall_sync(sprd_i2c_init);

Why?

--
With Best Regards,
Andy Shevchenko