mmc: Add concept of an 'embedded' SDIO device.

This is required to support chips which use SDIO for signaling/
communication but do not implement the various card enumeration registers
as required for full SD / SDIO cards.

mmc: sdio: Fix bug where we're freeing the CIS tables we never allocated when using EMBEDDED_SDIO
mmc: Add max_blksize to embedded SDIO data

Signed-off-by: San Mehat <san@google.com>

7 files changed, 130 insertions, 17 deletions

diff --git a/drivers/mmc/core/Kconfig b/drivers/mmc/core/Kconfig
index b2c6616d3b62..a7c3cdc59f76 100644
--- a/drivers/mmc/core/Kconfig
+++ b/drivers/mmc/core/Kconfig
@@ -27,8 +27,17 @@ config MMC_CLKGATE
 
 	  If unsure, say N.
 
+config MMC_EMBEDDED_SDIO
+	boolean "MMC embedded SDIO device support (EXPERIMENTAL)"
+	depends on EXPERIMENTAL
+	help
+	  If you say Y here, support will be added for embedded SDIO
+	  devices which do not contain the necessary enumeration
+	  support in hardware to be properly detected.
+
 config MMC_PARANOID_SD_INIT
 	bool "Enable paranoid SD card initialization (EXPERIMENTAL)"
+	depends on EXPERIMENTAL
 	help
 	  If you say Y here, the MMC layer will be extra paranoid
 	  about re-trying SD init requests. This can be a useful
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index c40396f23202..c57a28311df5 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2789,6 +2789,22 @@ void mmc_init_context_info(struct mmc_host *host)
 	init_waitqueue_head(&host->context_info.wait);
 }
 
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+void mmc_set_embedded_sdio_data(struct mmc_host *host,
+				struct sdio_cis *cis,
+				struct sdio_cccr *cccr,
+				struct sdio_embedded_func *funcs,
+				int num_funcs)
+{
+	host->embedded_sdio_data.cis = cis;
+	host->embedded_sdio_data.cccr = cccr;
+	host->embedded_sdio_data.funcs = funcs;
+	host->embedded_sdio_data.num_funcs = num_funcs;
+}
+
+EXPORT_SYMBOL(mmc_set_embedded_sdio_data);
+#endif
+
 static int __init mmc_init(void)
 {
 	int ret;
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 6889a821c1da..ab71380a744b 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -28,6 +28,10 @@
 #include "sdio_ops.h"
 #include "sdio_cis.h"
 
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+#include <linux/mmc/sdio_ids.h>
+#endif
+
 static int sdio_read_fbr(struct sdio_func *func)
 {
 	int ret;
@@ -728,19 +732,35 @@ try_again:
 		goto finish;
 	}
 
-	/*
-	 * Read the common registers.
-	 */
-	err = sdio_read_cccr(card, ocr);
-	if (err)
-		goto remove;
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	if (host->embedded_sdio_data.cccr)
+		memcpy(&card->cccr, host->embedded_sdio_data.cccr, sizeof(struct sdio_cccr));
+	else {
+#endif
+		/*
+		 * Read the common registers.
+		 */
+		err = sdio_read_cccr(card,  ocr);
+		if (err)
+			goto remove;
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	}
+#endif
 
-	/*
-	 * Read the common CIS tuples.
-	 */
-	err = sdio_read_common_cis(card);
-	if (err)
-		goto remove;
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	if (host->embedded_sdio_data.cis)
+		memcpy(&card->cis, host->embedded_sdio_data.cis, sizeof(struct sdio_cis));
+	else {
+#endif
+		/*
+		 * Read the common CIS tuples.
+		 */
+		err = sdio_read_common_cis(card);
+		if (err)
+			goto remove;
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	}
+#endif
 
 	if (oldcard) {
 		int same = (card->cis.vendor == oldcard->cis.vendor &&
@@ -1147,14 +1167,36 @@ int mmc_attach_sdio(struct mmc_host *host)
 	funcs = (ocr & 0x70000000) >> 28;
 	card->sdio_funcs = 0;
 
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	if (host->embedded_sdio_data.funcs)
+		card->sdio_funcs = funcs = host->embedded_sdio_data.num_funcs;
+#endif
+
 	/*
 	 * Initialize (but don't add) all present functions.
 	 */
 	for (i = 0; i < funcs; i++, card->sdio_funcs++) {
-		err = sdio_init_func(host->card, i + 1);
-		if (err)
-			goto remove;
-
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+		if (host->embedded_sdio_data.funcs) {
+			struct sdio_func *tmp;
+
+			tmp = sdio_alloc_func(host->card);
+			if (IS_ERR(tmp))
+				goto remove;
+			tmp->num = (i + 1);
+			card->sdio_func[i] = tmp;
+			tmp->class = host->embedded_sdio_data.funcs[i].f_class;
+			tmp->max_blksize = host->embedded_sdio_data.funcs[i].f_maxblksize;
+			tmp->vendor = card->cis.vendor;
+			tmp->device = card->cis.device;
+		} else {
+#endif
+			err = sdio_init_func(host->card, i + 1);
+			if (err)
+				goto remove;
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+		}
+#endif
 		/*
 		 * Enable Runtime PM for this func (if supported)
 		 */
diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
index 546c67c2bbbf..c012cf59b7d6 100644
--- a/drivers/mmc/core/sdio_bus.c
+++ b/drivers/mmc/core/sdio_bus.c
@@ -25,6 +25,10 @@
 #include "sdio_cis.h"
 #include "sdio_bus.h"
 
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+#include <linux/mmc/host.h>
+#endif
+
 /* show configuration fields */
 #define sdio_config_attr(field, format_string)				\
 static ssize_t								\
@@ -270,7 +274,14 @@ static void sdio_release_func(struct device *dev)
 {
 	struct sdio_func *func = dev_to_sdio_func(dev);
 
-	sdio_free_func_cis(func);
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	/*
+	 * If this device is embedded then we never allocated
+	 * cis tables for this func
+	 */
+	if (!func->card->host->embedded_sdio_data.funcs)
+#endif
+		sdio_free_func_cis(func);
 
 	kfree(func->info);
 
diff --git a/include/linux/amba/mmci.h b/include/linux/amba/mmci.h
index 0926063bff9f..9d1d9caf2611 100644
--- a/include/linux/amba/mmci.h
+++ b/include/linux/amba/mmci.h
@@ -5,6 +5,15 @@
 #define AMBA_MMCI_H
 
 #include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include <linux/mmc/sdio_func.h>
+
+struct embedded_sdio_data {
+        struct sdio_cis cis;
+        struct sdio_cccr cccr;
+        struct sdio_embedded_func *funcs;
+        int num_funcs;
+};
 
 
 /*
@@ -74,6 +83,7 @@ struct mmci_platform_data {
 	void *dma_rx_param;
 	void *dma_tx_param;
 	unsigned int status_irq;
+	struct embedded_sdio_data *embedded_sdio;
 	int (*register_status_notify)(void (*callback)(int card_present, void *dev_id), void *dev_id);
 };
 
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index e326ae2882a0..cb0f69a04e57 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -362,6 +362,15 @@ struct mmc_host {
 
 	unsigned int		slotno;	/* used for sdio acpi binding */
 
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+	struct {
+		struct sdio_cis			*cis;
+		struct sdio_cccr		*cccr;
+		struct sdio_embedded_func	*funcs;
+		int				num_funcs;
+	} embedded_sdio_data;
+#endif
+
 	unsigned long		private[0] ____cacheline_aligned;
 };
 
@@ -371,6 +380,14 @@ void mmc_remove_host(struct mmc_host *);
 void mmc_free_host(struct mmc_host *);
 void mmc_of_parse(struct mmc_host *host);
 
+#ifdef CONFIG_MMC_EMBEDDED_SDIO
+extern void mmc_set_embedded_sdio_data(struct mmc_host *host,
+				       struct sdio_cis *cis,
+				       struct sdio_cccr *cccr,
+				       struct sdio_embedded_func *funcs,
+				       int num_funcs);
+#endif
+
 static inline void *mmc_priv(struct mmc_host *host)
 {
 	return (void *)host->private;
diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h
index 50f0bc952328..54600e927b06 100644
--- a/include/linux/mmc/sdio_func.h
+++ b/include/linux/mmc/sdio_func.h
@@ -23,6 +23,14 @@ struct sdio_func;
 typedef void (sdio_irq_handler_t)(struct sdio_func *);
 
 /*
+ * Structure used to hold embedded SDIO device data from platform layer
+ */
+struct sdio_embedded_func {
+	uint8_t f_class;
+	uint32_t f_maxblksize;
+};
+
+/*
  * SDIO function CIS tuple (unknown to the core)
  */
 struct sdio_func_tuple {