Re: [PATCH arm/aspeed/ast2500 v2] eSPI: add ASPEED AST2500 eSPI driver to boot a host with PCH runs on eSPI

[Wang, Haiyue]

On 2018-02-23 18:25, Andy Shevchenko wrote:
> On Fri, 2018-02-23 at 15:04 +0800, Haiyue Wang wrote:
> > When PCH works under eSPI mode, the PMC (Power Management Controller)
> > in
> > PCH is waiting for SUS_ACK from BMC after it alerts SUS_WARN. It is in
> > dead loop if no SUS_ACK assert. This is the basic requirement for the
> > BMC
> > works as eSPI slave.
> So, do we have an agreement that the driver should go in this shape w/o
> interacting with SPI subsystem?
Not sure, I've added the specification of eSPI, hope people don't feel 
confused with SPI. :-)
> Also few comments below.
>
> > +config ASPEED_ESPI_SLAVE
> > +	depends on (ARCH_ASPEED || COMPILE_TEST) && REGMAP_MMIO
> I would rather split this to two
> 	depends on REGMAP_MMIO
> 	depends on ARCH_ASPEED || COMPILE_TEST
OK, it looks clean. I referred to:
config ASPEED_LPC_CTRL
ÂÂÂÂÂÂÂ depends on (ARCH_ASPEED || COMPILE_TEST) && REGMAP && MFD_SYSCON

> > +	tristate "Aspeed ast2500 eSPI slave device driver"
> > +	---help---
> > +	  Control Aspeed ast2500 eSPI slave controller to handle
> > event
> > +	  which needs the firmware's processing.
> > +#include <linux/of.h>
> What exactly requires this header?
Oh, I ctrl+c / ctrl+v from other device tree usage module. :-(
Remove it now. Thanks for making the code more clean.
> > +static int aspeed_espi_slave_probe(struct platform_device *pdev)
> > +{
> > +	struct aspeed_espi_slave_data *priv;
> > +	struct device *dev = &pdev->dev;
> > +	struct resource *res;
> > +	void __iomem *regs;
> > +	int rc;
> > +
> > +	dev_set_name(dev, DEVICE_NAME);
> Do this after checks and memory allocations.
Fixed!
> > +
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	regs = devm_ioremap_resource(dev, res);
> > +	if (IS_ERR(regs))
> > +		return PTR_ERR(regs);
> > +
> > +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return -ENOMEM;
> > +
> > +	priv->map = devm_regmap_init_mmio(dev, regs,
> > &espi_slave_regmap_cfg);
> > +	if (IS_ERR(priv->map))
> > +		return PTR_ERR(priv->map);
> > +
> > +static const struct of_device_id of_espi_slave_match_table[] = {
> > +	{ .compatible = "aspeed,ast2500-espi-slave" },
> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(of, of_espi_slave_match_table);
> This one should be closer to the struct of_device_id.
Fixed.