mmc: sdhci: Allow caps[1] to be set via SDHCI_QUIRK_MISSING_CAPS

Currently only the capability_0 register can be set if
SDHCI_QUIRK_MISSING_CAPS is defined.  This is a problem when
the capability_1 register also needs changing.  Use the quirk
SDHCI_QUIRK_MISSING_CAPS to allow both registers to be set.

Redefining caps[1] is useful when the board design does not
support 1.8v vccq so UHS modes are not available.  The code that
calls sdhci_add_host can then detect this condition and adjust
the caps so the UHS mode will not be attempted on UHS cards.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/sdhci.c

@@ -2584,7 +2584,7 @@ EXPORT_SYMBOL_GPL(sdhci_alloc_host);
 int sdhci_add_host(struct sdhci_host *host)
 {
 	struct mmc_host *mmc;
-	u32 caps[2];
+	u32 caps[2] = {0, 0};
 	u32 max_current_caps;
 	unsigned int ocr_avail;
 	int ret;
@@ -2614,8 +2614,10 @@ int sdhci_add_host(struct sdhci_host *host)
 	caps[0] = (host->quirks & SDHCI_QUIRK_MISSING_CAPS) ? host->caps :
 		sdhci_readl(host, SDHCI_CAPABILITIES);
 
-	caps[1] = (host->version >= SDHCI_SPEC_300) ?
-		sdhci_readl(host, SDHCI_CAPABILITIES_1) : 0;
+	if (host->version >= SDHCI_SPEC_300)
+		caps[1] = (host->quirks & SDHCI_QUIRK_MISSING_CAPS) ?
+			host->caps1 :
+			sdhci_readl(host, SDHCI_CAPABILITIES_1);
 
 	if (host->quirks & SDHCI_QUIRK_FORCE_DMA)
 		host->flags |= SDHCI_USE_SDMA;

include/linux/mmc/sdhci.h

@@ -155,7 +155,8 @@ struct sdhci_host {
 
 	struct timer_list timer;	/* Timer for timeouts */
 
-	unsigned int caps;	/* Alternative capabilities */
+	unsigned int caps;	/* Alternative CAPABILITY_0 */
+	unsigned int caps1;	/* Alternative CAPABILITY_1 */
 
 	unsigned int            ocr_avail_sdio;	/* OCR bit masks */
 	unsigned int            ocr_avail_sd;