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

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?

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

+	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?

+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.

+
+	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.

-- 
Andy Shevchenko [off-list ref]
Intel Finland Oy