mmc: Test bus-width for old MMC devices

Some old MMC devices fail with the 4/8 bits the driver tries to use
exclusively.  This patch adds a test for the given bus setup and falls
back to the lower bit mode (until 1-bit mode) when the test fails.

[Major rework and refactoring by tiwai]
[Quirk addition and many fixes by prakity]

Signed-off-by: Aries Lee <arieslee@jmicron.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

2 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 3a85e73a38a9..bcb793ec7374 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -172,6 +172,7 @@ struct mmc_host {
 #define MMC_CAP_1_2V_DDR        (1 << 12)       /* can support */
                                                 /* DDR mode at 1.2V */
 #define MMC_CAP_POWER_OFF_CARD  (1 << 13)       /* Can power off after boot */
+#define MMC_CAP_BUS_WIDTH_TEST  (1 << 14)       /* CMD14/CMD19 bus width ok */
 
         mmc_pm_flag_t           pm_caps;        /* supported pm features */
 
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 956fbd877692..612301f85d14 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -40,7 +40,9 @@
 #define MMC_READ_DAT_UNTIL_STOP  11   /* adtc [31:0] dadr        R1  */
 #define MMC_STOP_TRANSMISSION    12   /* ac                      R1b */
 #define MMC_SEND_STATUS          13   /* ac   [31:16] RCA        R1  */
+#define MMC_BUS_TEST_R           14   /* adtc                    R1  */
 #define MMC_GO_INACTIVE_STATE    15   /* ac   [31:16] RCA            */
+#define MMC_BUS_TEST_W           19   /* adtc                    R1  */
 #define MMC_SPI_READ_OCR         58   /* spi                  spi_R3 */
 #define MMC_SPI_CRC_ON_OFF       59   /* spi  [0:0] flag      spi_R1 */