[01/12,SRU,B,C,D,OEM-B] mmc: sdhci: Disable 1.8v modes (HS200/HS400/UHS) if controller can't support 1.8v

Message ID 20190111083019.32135-2-acelan.kao@canonical.com
State New
Headers show
Series
  • To reduce the Realtek USB cardreader power consumption
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Commit Message

AceLan Kao Jan. 11, 2019, 8:30 a.m.
From: Kishon Vijay Abraham I <kishon@ti.com>

BugLink: https://bugs.launchpad.net/bugs/1811337

The SDHCI controller in a SoC might support HS200/HS400 (indicated
using mmc-hs200-1_8v/mmc-hs400-1_8v dt property), but if the board is
modeled such that the IO lines are not connected to 1.8v then
HS200/HS400 cannot be supported. Disable HS200/HS400 if the board
does not have 1.8v connected to the IO lines. Also Disable DDR/UHS in 1.8v
if the IO lines are not connected to 1.8v.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
(cherry picked from commit c16bc9a7678a27ece028dcbfea8df2049a65dbec)
Signed-off-by: AceLan Kao <acelan.kao@canonical.com>
---
 drivers/mmc/host/sdhci.c | 10 ++++++++++
 include/linux/mmc/host.h |  4 ++++
 2 files changed, 14 insertions(+)

Patch

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 3a5f305fd442..3f2fd9f466bf 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3649,6 +3649,16 @@  int sdhci_setup_host(struct sdhci_host *host)
 	if (host->quirks2 & SDHCI_QUIRK2_NO_1_8_V) {
 		host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_SDR50 |
 				 SDHCI_SUPPORT_DDR50);
+		/*
+		 * The SDHCI controller in a SoC might support HS200/HS400
+		 * (indicated using mmc-hs200-1_8v/mmc-hs400-1_8v dt property),
+		 * but if the board is modeled such that the IO lines are not
+		 * connected to 1.8v then HS200/HS400 cannot be supported.
+		 * Disable HS200/HS400 if the board does not have 1.8v connected
+		 * to the IO lines. (Applicable for other modes in 1.8v)
+		 */
+		mmc->caps2 &= ~(MMC_CAP2_HSX00_1_8V | MMC_CAP2_HS400_ES);
+		mmc->caps &= ~(MMC_CAP_1_8V_DDR | MMC_CAP_UHS);
 	}
 
 	/* Any UHS-I mode in caps implies SDR12 and SDR25 support. */
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index e7743eca1021..b36723e8e99b 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -320,6 +320,9 @@  struct mmc_host {
 #define MMC_CAP_UHS_SDR50	(1 << 18)	/* Host supports UHS SDR50 mode */
 #define MMC_CAP_UHS_SDR104	(1 << 19)	/* Host supports UHS SDR104 mode */
 #define MMC_CAP_UHS_DDR50	(1 << 20)	/* Host supports UHS DDR50 mode */
+#define MMC_CAP_UHS		(MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 | \
+				 MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 | \
+				 MMC_CAP_UHS_DDR50)
 /* (1 << 21) is free for reuse */
 #define MMC_CAP_DRIVER_TYPE_A	(1 << 23)	/* Host supports Driver Type A */
 #define MMC_CAP_DRIVER_TYPE_C	(1 << 24)	/* Host supports Driver Type C */
@@ -344,6 +347,7 @@  struct mmc_host {
 #define MMC_CAP2_HS400_1_2V	(1 << 16)	/* Can support HS400 1.2V */
 #define MMC_CAP2_HS400		(MMC_CAP2_HS400_1_8V | \
 				 MMC_CAP2_HS400_1_2V)
+#define MMC_CAP2_HSX00_1_8V	(MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V)
 #define MMC_CAP2_HSX00_1_2V	(MMC_CAP2_HS200_1_2V_SDR | MMC_CAP2_HS400_1_2V)
 #define MMC_CAP2_SDIO_IRQ_NOTHREAD (1 << 17)
 #define MMC_CAP2_NO_WRITE_PROTECT (1 << 18)	/* No physical write protect pin, assume that card is always read-write */