mmc: sdhci: track whether preset mode is currently enabled in hardware

Track whether preset mode is currently enabled in hardware, and use that
when making decisions elsewhere in the code rather than reading the
register and checking the bit.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Markus Pargmann <mpa@pengutronix.de>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index effd9e5d1d817da2520c7729f68b70dee6fd9e0f..447eef8217c7b4753cbad777a102af97d53d7daa 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -205,9 +205,14 @@ static void sdhci_do_reset(struct sdhci_host *host, u8 mask)
 
        host->ops->reset(host, mask);
 
-       if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
-               if ((host->ops->enable_dma) && (mask & SDHCI_RESET_ALL))
-                       host->ops->enable_dma(host);
+       if (mask & SDHCI_RESET_ALL) {
+               if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
+                       if (host->ops->enable_dma)
+                               host->ops->enable_dma(host);
+               }
+
+               /* Resetting the controller clears many */
+               host->preset_enabled = false;
        }
 }
 
@@ -1126,8 +1131,7 @@ void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
                return;
 
        if (host->version >= SDHCI_SPEC_300) {
-               if (sdhci_readw(host, SDHCI_HOST_CONTROL2) &
-                       SDHCI_CTRL_PRESET_VAL_ENABLE) {
+               if (host->preset_enabled) {
                        u16 pre_val;
 
                        clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
@@ -1493,13 +1497,13 @@ static void sdhci_do_set_ios(struct sdhci_host *host, struct mmc_ios *ios)
                    (ios->timing == MMC_TIMING_UHS_SDR25))
                        ctrl |= SDHCI_CTRL_HISPD;
 
-               ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
-               if (!(ctrl_2 & SDHCI_CTRL_PRESET_VAL_ENABLE)) {
+               if (!host->preset_enabled) {
                        sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
                        /*
                         * We only need to set Driver Strength if the
                         * preset value enable is not set.
                         */
+                       ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
                        ctrl_2 &= ~SDHCI_CTRL_DRV_TYPE_MASK;
                        if (ios->drv_type == MMC_SET_DRIVER_TYPE_A)
                                ctrl_2 |= SDHCI_CTRL_DRV_TYPE_A;
@@ -2018,26 +2022,30 @@ out:
 
 static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable)
 {
-       u16 ctrl;
-
        /* Host Controller v3.00 defines preset value registers */
        if (host->version < SDHCI_SPEC_300)
                return;
 
-       ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
-
        /*
         * We only enable or disable Preset Value if they are not already
         * enabled or disabled respectively. Otherwise, we bail out.
         */
-       if (enable && !(ctrl & SDHCI_CTRL_PRESET_VAL_ENABLE)) {
-               ctrl |= SDHCI_CTRL_PRESET_VAL_ENABLE;
-               sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
-               host->flags |= SDHCI_PV_ENABLED;
-       } else if (!enable && (ctrl & SDHCI_CTRL_PRESET_VAL_ENABLE)) {
-               ctrl &= ~SDHCI_CTRL_PRESET_VAL_ENABLE;
+       if (host->preset_enabled != enable) {
+               u16 ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+
+               if (enable)
+                       ctrl |= SDHCI_CTRL_PRESET_VAL_ENABLE;
+               else
+                       ctrl &= ~SDHCI_CTRL_PRESET_VAL_ENABLE;
+
                sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
-               host->flags &= ~SDHCI_PV_ENABLED;
+
+               if (enable)
+                       host->flags |= SDHCI_PV_ENABLED;
+               else
+                       host->flags &= ~SDHCI_PV_ENABLED;
+
+               host->preset_enabled = enable;
        }
 }
 

diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 7f3efbab87327916e1e8a9dd52977054c36ae5a5..08abe9941884ebc40667ee246881b2b2bfd66f70 100644 (file)
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -143,6 +143,7 @@ struct sdhci_host {
 
        bool runtime_suspended; /* Host is runtime suspended */
        bool bus_on;            /* Bus power prevents runtime suspend */
+       bool preset_enabled;    /* Preset is enabled */
 
        struct mmc_request *mrq;        /* Current request */
        struct mmc_command *cmd;        /* Current command */