[MMC] sdhci: more DMA capabilities tests
Properly test for controller interface to see if it's DMA capable. As many
controllers are misconfigured in this regard, also add debug parameters to
force DMA support either way.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 06dec74..315ab49 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -28,6 +28,9 @@
#define DBG(f, x...) \
pr_debug(DRIVER_NAME " [%s()]: " f, __func__,## x)
+static unsigned int debug_nodma = 0;
+static unsigned int debug_forcedma = 0;
+
static const struct pci_device_id pci_ids[] __devinitdata = {
/* handle any SD host controller */
{PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)},
@@ -1105,6 +1108,16 @@
return -ENODEV;
}
+ if ((pdev->class & 0x0000FF) == PCI_SDHCI_IFVENDOR) {
+ printk(KERN_ERR DRIVER_NAME ": Vendor specific interface. Aborting.\n");
+ return -ENODEV;
+ }
+
+ if ((pdev->class & 0x0000FF) > PCI_SDHCI_IFVENDOR) {
+ printk(KERN_ERR DRIVER_NAME ": Unknown interface. Aborting.\n");
+ return -ENODEV;
+ }
+
mmc = mmc_alloc_host(sizeof(struct sdhci_host), &pdev->dev);
if (!mmc)
return -ENOMEM;
@@ -1146,7 +1159,16 @@
caps = readl(host->ioaddr + SDHCI_CAPABILITIES);
- if ((caps & SDHCI_CAN_DO_DMA) && ((pdev->class & 0x0000FF) == 0x01))
+ if (debug_nodma)
+ DBG("DMA forced off\n");
+ else if (debug_forcedma) {
+ DBG("DMA forced on\n");
+ host->flags |= SDHCI_USE_DMA;
+ } else if ((pdev->class & 0x0000FF) != PCI_SDHCI_IFDMA)
+ DBG("Controller doesn't have DMA interface\n");
+ else if (!(caps & SDHCI_CAN_DO_DMA))
+ DBG("Controller doesn't have DMA capability\n");
+ else
host->flags |= SDHCI_USE_DMA;
if (host->flags & SDHCI_USE_DMA) {
@@ -1429,7 +1451,13 @@
module_init(sdhci_drv_init);
module_exit(sdhci_drv_exit);
+module_param(debug_nodma, uint, 0444);
+module_param(debug_forcedma, uint, 0444);
+
MODULE_AUTHOR("Pierre Ossman <drzeus@drzeus.cx>");
MODULE_DESCRIPTION("Secure Digital Host Controller Interface driver");
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");
+
+MODULE_PARM_DESC(debug_nodma, "Forcefully disable DMA transfers. (default 0)");
+MODULE_PARM_DESC(debug_forcedma, "Forcefully enable DMA transfers. (default 0)");