spi/pxa2xx-pci: Add PCI mode support for BayTrail LPSS SPI

Similar to CE4100, BayTrail LPSS SPI can be PCI enumerated
as well. Thus, the functions are renamed from ce4100_xxx
to pxa2xx_spi_pci_xxx to clarify that this is a generic
PCI glue layer. Also, added required infrastructure to
support SPI hosts with different configurations.

This patch is based on Mika Westerberg's previous work.

Signed-off-by: Chew, Chiau Ee <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

drivers/spi/spi-pxa2xx-pci.c

···
 #include <linux/module.h>
 #include <linux/spi/pxa2xx_spi.h>
 
-static int ce4100_spi_probe(struct pci_dev *dev,
+enum {
+	PORT_CE4100,
+	PORT_BYT,
+};
+
+struct pxa_spi_info {
+	enum pxa_ssp_type type;
+	int port_id;
+	int num_chipselect;
+	int tx_slave_id;
+	int tx_chan_id;
+	int rx_slave_id;
+	int rx_chan_id;
+};
+
+static struct pxa_spi_info spi_info_configs[] = {
+	[PORT_CE4100] = {
+		.type = PXA25x_SSP,
+		.port_id =  -1,
+		.num_chipselect = -1,
+		.tx_slave_id = -1,
+		.tx_chan_id = -1,
+		.rx_slave_id = -1,
+		.rx_chan_id = -1,
+	},
+	[PORT_BYT] = {
+		.type = LPSS_SSP,
+		.port_id = 0,
+		.num_chipselect = 1,
+		.tx_slave_id = 0,
+		.tx_chan_id = 0,
+		.rx_slave_id = 1,
+		.rx_chan_id = 1,
+	},
+};
+
+static int pxa2xx_spi_pci_probe(struct pci_dev *dev,
 		const struct pci_device_id *ent)
 {
 	struct platform_device_info pi;
···
 	struct platform_device *pdev;
 	struct pxa2xx_spi_master spi_pdata;
 	struct ssp_device *ssp;
+	struct pxa_spi_info *c;
 
 	ret = pcim_enable_device(dev);
 	if (ret)
···
 	if (ret)
 		return ret;
 
+	c = &spi_info_configs[ent->driver_data];
+
 	memset(&spi_pdata, 0, sizeof(spi_pdata));
-	spi_pdata.num_chipselect = dev->devfn;
+	spi_pdata.num_chipselect = (c->num_chipselect > 0) ?
+					c->num_chipselect : dev->devfn;
+	spi_pdata.tx_slave_id = c->tx_slave_id;
+	spi_pdata.tx_chan_id = c->tx_chan_id;
+	spi_pdata.rx_slave_id = c->rx_slave_id;
+	spi_pdata.rx_chan_id = c->rx_chan_id;
+	spi_pdata.enable_dma = c->rx_slave_id >= 0 && c->tx_slave_id >= 0;
 
 	ssp = &spi_pdata.ssp;
 	ssp->phys_base = pci_resource_start(dev, 0);
···
 		return -EIO;
 	}
 	ssp->irq = dev->irq;
-	ssp->port_id = dev->devfn;
-	ssp->type = PXA25x_SSP;
+	ssp->port_id = (c->port_id >= 0) ? c->port_id : dev->devfn;
+	ssp->type = c->type;
 
 	memset(&pi, 0, sizeof(pi));
 	pi.parent = &dev->dev;
···
 	return 0;
 }
 
-static void ce4100_spi_remove(struct pci_dev *dev)
+static void pxa2xx_spi_pci_remove(struct pci_dev *dev)
 {
 	struct platform_device *pdev = pci_get_drvdata(dev);
 
 	platform_device_unregister(pdev);
 }
 
-static const struct pci_device_id ce4100_spi_devices[] = {
-	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e6a) },
+static const struct pci_device_id pxa2xx_spi_pci_devices[] = {
+	{ PCI_VDEVICE(INTEL, 0x2e6a), PORT_CE4100 },
+	{ PCI_VDEVICE(INTEL, 0x0f0e), PORT_BYT },
 	{ },
 };
-MODULE_DEVICE_TABLE(pci, ce4100_spi_devices);
+MODULE_DEVICE_TABLE(pci, pxa2xx_spi_pci_devices);
 
-static struct pci_driver ce4100_spi_driver = {
-	.name           = "ce4100_spi",
-	.id_table       = ce4100_spi_devices,
-	.probe          = ce4100_spi_probe,
-	.remove         = ce4100_spi_remove,
+static struct pci_driver pxa2xx_spi_pci_driver = {
+	.name           = "pxa2xx_spi_pci",
+	.id_table       = pxa2xx_spi_pci_devices,
+	.probe          = pxa2xx_spi_pci_probe,
+	.remove         = pxa2xx_spi_pci_remove,
 };
 
-module_pci_driver(ce4100_spi_driver);
+module_pci_driver(pxa2xx_spi_pci_driver);
 
-MODULE_DESCRIPTION("CE4100 PCI-SPI glue code for PXA's driver");
+MODULE_DESCRIPTION("CE4100/LPSS PCI-SPI glue code for PXA's driver");
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Sebastian Andrzej Siewior <[e-mail]>");