mmc: sdhci-pci: Let devices define their own private data

Let devices define their own private data to facilitate device-specific
operations. The size of the private structure is specified in the
sdhci_pci_fixes structure, then sdhci_pci_probe_slot() will allocate extra
space for it, and sdhci_pci_priv() can be used to get a reference to it.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ludovic Desroches <ludovic.desroches@microchip.com>

drivers/mmc/host/sdhci-pci-core.c

@@ -1830,6 +1830,7 @@ static struct sdhci_pci_slot *sdhci_pci_probe_slot(
 	struct sdhci_pci_slot *slot;
 	struct sdhci_host *host;
 	int ret, bar = first_bar + slotno;
+	size_t priv_size = chip->fixes ? chip->fixes->priv_size : 0;
 
 	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
 		dev_err(&pdev->dev, "BAR %d is not iomem. Aborting.\n", bar);
@@ -1851,7 +1852,7 @@ static struct sdhci_pci_slot *sdhci_pci_probe_slot(
 		return ERR_PTR(-ENODEV);
 	}
 
-	host = sdhci_alloc_host(&pdev->dev, sizeof(struct sdhci_pci_slot));
+	host = sdhci_alloc_host(&pdev->dev, sizeof(*slot) + priv_size);
 	if (IS_ERR(host)) {
 		dev_err(&pdev->dev, "cannot allocate host\n");
 		return ERR_CAST(host);

drivers/mmc/host/sdhci-pci.h

@@ -70,6 +70,7 @@ struct sdhci_pci_fixes {
 	int			(*resume) (struct sdhci_pci_chip *);
 
 	const struct sdhci_ops	*ops;
+	size_t			priv_size;
 };
 
 struct sdhci_pci_slot {
@@ -89,6 +90,7 @@ struct sdhci_pci_slot {
 				     struct mmc_card *card,
 				     unsigned int max_dtr, int host_drv,
 				     int card_drv, int *drv_type);
+	unsigned long		private[0] ____cacheline_aligned;
 };
 
 struct sdhci_pci_chip {
@@ -105,4 +107,9 @@ struct sdhci_pci_chip {
 	struct sdhci_pci_slot	*slots[MAX_SLOTS]; /* Pointers to host slots */
 };
 
+static inline void *sdhci_pci_priv(struct sdhci_pci_slot *slot)
+{
+	return (void *)slot->private;
+}
+
 #endif /* __SDHCI_PCI_H */