Re: [PATCH v6 6/8] i2c: amd-asf: Add routine to handle the ASF slave process

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Thu, Sep 19, 2024 at 11:29:11PM +0530, Shyam Sundar S K wrote:
> Add support for handling ASF slave process events as described in the AMD
> ASF databook. This involves implementing the correct programming sequence
> to manage each ASF packet appropriately.

...

> +static void amd_asf_process_target(struct work_struct *work)
> +{
> +	struct amd_asf_dev *dev = container_of(work, struct amd_asf_dev, work_buf.work);
> +	unsigned short piix4_smba = dev->port_addr->start;
> +	u8 data[ASF_BLOCK_MAX_BYTES];
> +	u8 bank, reg, cmd;
> +	u8 len, idx, val;
> +
> +	/* Read target status register */
> +	reg = inb_p(ASFSLVSTA);
> +
> +	/* Check if no error bits are set in target status register */
> +	if (reg & ASF_ERROR_STATUS) {
> +		/* Set bank as full */
> +		cmd = 0;
> +		reg = reg | GENMASK(3, 2);

		reg |= ...

> +		outb_p(reg, ASFDATABNKSEL);
> +	} else {
> +		/* Read data bank */
> +		reg = inb_p(ASFDATABNKSEL);
> +		bank = (reg & BIT(3)) ? 1 : 0;

> +		/* Set read data bank */
> +		if (bank) {
> +			reg = reg | BIT(4);
> +			reg = reg & ~BIT(3);
> +		} else {
> +			reg = reg & ~BIT(4);
> +			reg = reg & ~BIT(2);
> +		}

		/* Set read data bank */
		if (bank) {
			reg |= BIT(4);
			reg &= ~BIT(3);
		} else {
			reg &= ~BIT(4);
			reg &= ~BIT(2);
		}

> +		/* Read command register */
> +		outb_p(reg, ASFDATABNKSEL);
> +		cmd = inb_p(ASFINDEX);
> +		len = inb_p(ASFDATARWPTR);
> +		for (idx = 0; idx < len; idx++)
> +			data[idx] = inb_p(ASFINDEX);

> +		/* Clear data bank status */
> +		if (bank) {
> +			reg = reg | BIT(3);
> +			outb_p(reg, ASFDATABNKSEL);
> +		} else {
> +			reg = reg | BIT(2);
> +			outb_p(reg, ASFDATABNKSEL);
> +		}

		/* Clear data bank status */
		if (bank) {
			reg |= BIT(3);
			outb_p(reg, ASFDATABNKSEL);
		} else {
			reg |= BIT(2);
			outb_p(reg, ASFDATABNKSEL);
		}

> +	}
> +
> +	outb_p(0, ASFSETDATARDPTR);
> +	if (cmd & BIT(0))
> +		return;
> +
> +	/*
> +	 * Although i2c_slave_event() returns an appropriate error code, we
> +	 * don't check it here because we're operating in the workqueue context.
> +	 */
> +	i2c_slave_event(dev->target, I2C_SLAVE_WRITE_REQUESTED, &val);
> +	for (idx = 0; idx < len; idx++) {
> +		val = data[idx];
> +		i2c_slave_event(dev->target, I2C_SLAVE_WRITE_RECEIVED, &val);
> +	}
> +	i2c_slave_event(dev->target, I2C_SLAVE_STOP, &val);
> +}

...


Perhaps it's time to have

	struct device *dev = &pdev->dev;

> +	ret = devm_delayed_work_autocancel(&pdev->dev, &asf_dev->work_buf, amd_asf_process_target);
> +	if (ret)
> +		return dev_err_probe(&pdev->dev, ret, "failed to create work queue\n");

...and this, in particular, becomes shorter.

	ret = devm_delayed_work_autocancel(dev, &asf_dev->work_buf, amd_asf_process_target);
	if (ret)
		return dev_err_probe(dev, ret, "failed to create work queue\n");

> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return dev_err_probe(&pdev->dev, irq, "missing IRQ resources\n");
> +
> +	ret = devm_request_irq(&pdev->dev, irq, amd_asf_irq_handler, IRQF_SHARED,
> +			       "amd_asf", asf_dev);

This even can be one line after proposed change.

> +	if (ret)
> +		return dev_err_probe(&pdev->dev, ret, "Unable to request irq: %d for use\n", irq);

...

With the above changes being applied
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko