From a89dfb1bbd09b7625eca50ce02448a517c7156c6 Mon Sep 17 00:00:00 2001
From: Talel Shenhar <tatias@codeaurora.org>
Date: Thu, 5 Feb 2015 14:44:15 +0200
Subject: [PATCH] mmc: quirks: add new quirk that allows HPI disable

Certain cards might get broken when HPI feature is used.
This patch allows host to avoid using HPI for such
buggy cards by adding new quirk.

As some of the other features like BKOPs/Cache are
dependent on HPI feature, those features would also
get disabled if HPI is disabled.

Change-Id: I93a8810e4031eafcd44b5152296e065dc3330b63
Signed-off-by: Talel Shenhar <tatias@codeaurora.org>
---
 drivers/mmc/core/mmc.c     | 22 ++++++++++++++++++++--
 drivers/mmc/core/mmc_ops.c |  2 +-
 include/linux/mmc/card.h   |  2 ++
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 93b0b596dd20..087e9ea1fda0 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -490,13 +490,30 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
 			ext_csd[EXT_CSD_PWR_CL_DDR_200_360];
 	}
 
+	/* check whether the eMMC card supports HPI */
+	if ((ext_csd[EXT_CSD_HPI_FEATURES] & 0x1) &&
+		!(card->quirks & MMC_QUIRK_BROKEN_HPI)) {
+		card->ext_csd.hpi = 1;
+		if (ext_csd[EXT_CSD_HPI_FEATURES] & 0x2)
+			card->ext_csd.hpi_cmd = MMC_STOP_TRANSMISSION;
+		else
+			card->ext_csd.hpi_cmd = MMC_SEND_STATUS;
+		/*
+		 * Indicate the maximum timeout to close
+		 * a command interrupted by HPI
+		 */
+		card->ext_csd.out_of_int_time =
+			ext_csd[EXT_CSD_OUT_OF_INTERRUPT_TIME] * 10;
+	}
+
 	if (card->ext_csd.rev >= 5) {
 		/* Adjust production date as per JEDEC JESD84-B451 */
 		if (card->cid.year < 2010)
 			card->cid.year += 16;
 
 		/* check whether the eMMC card supports BKOPS */
-		if (ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) {
+		if ((ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) &&
+				card->ext_csd.hpi) {
 			card->ext_csd.bkops = 1;
 			card->ext_csd.man_bkops_en =
 					(ext_csd[EXT_CSD_BKOPS_EN] &
@@ -1788,8 +1805,9 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	/*
 	 * If cache size is higher than 0, this indicates
 	 * the existence of cache and it can be turned on.
+	 * If HPI is not supported then cache shouldn't be enabled.
 	 */
-	if (card->ext_csd.cache_size > 0) {
+	if (card->ext_csd.cache_size > 0 && card->ext_csd.hpi_en) {
 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
 				EXT_CSD_CACHE_CTRL, 1,
 				card->ext_csd.generic_cmd6_time);
diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 91248c14af01..6384bf34660f 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -767,7 +767,7 @@ int mmc_send_hpi_cmd(struct mmc_card *card, u32 *status)
 	unsigned int opcode;
 	int err;
 
-	if (!card->ext_csd.hpi) {
+	if (!card->ext_csd.hpi_en) {
 		pr_warn("%s: Card didn't support HPI command\n",
 			mmc_hostname(card->host));
 		return -EINVAL;
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index a9c756549c2f..a16fd1739371 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -306,6 +306,8 @@ struct mmc_card {
 #define MMC_QUIRK_TRIM_BROKEN	(1<<12)		/* Skip trim */
 						/* byte mode */
 #define MMC_QUIRK_INAND_DATA_TIMEOUT  (1<<13)   /* For incorrect data timeout */
+#define MMC_QUIRK_BROKEN_HPI (1 << 14)		/* For devices which gets */
+						/* broken due to HPI feature */
 
 
 	unsigned int		erase_size;	/* erase size in sectors */