The Write Protect pin of SDHCI model is default active low to match the SDHCI
spec. So, write enable the bit 19 should be 1 and write protected the bit 19
should be 0 at the Present State Register (0x24). However, some boards are
design Write Protected pin active high. In other words, write enable the bit 19
should be 0 and write protected the bit 19 should be 1 at the
Present State Register (0x24). To support it, introduces a new "wp-inverted"
property and set it false by default.

Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Acked-by: Cédric Le Goater <clg@redhat.com>
---
 hw/sd/sdhci.c         | 6 ++++++
 include/hw/sd/sdhci.h | 5 +++++
 2 files changed, 11 insertions(+)

diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index 37875c02c3..06d1e24086 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -274,6 +274,10 @@ static void sdhci_set_readonly(DeviceState *dev, bool level)
 {
     SDHCIState *s = (SDHCIState *)dev;
 
+    if (s->wp_inverted) {
+        level = !level;
+    }
+
     if (level) {
         s->prnsts &= ~SDHC_WRITE_PROTECT;
     } else {
@@ -1550,6 +1554,8 @@ static Property sdhci_sysbus_properties[] = {
                      false),
     DEFINE_PROP_LINK("dma", SDHCIState,
                      dma_mr, TYPE_MEMORY_REGION, MemoryRegion *),
+    DEFINE_PROP_BOOL("wp-inverted", SDHCIState,
+                     wp_inverted, false),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/include/hw/sd/sdhci.h b/include/hw/sd/sdhci.h
index 6cd2822f1d..38c08e2859 100644
--- a/include/hw/sd/sdhci.h
+++ b/include/hw/sd/sdhci.h
@@ -100,6 +100,11 @@ struct SDHCIState {
     uint8_t sd_spec_version;
     uint8_t uhs_mode;
     uint8_t vendor;        /* For vendor specific functionality */
+    /*
+     * Write Protect pin default active low for detecting SD card
+     * to be protected. Set wp_inverted to invert the signal.
+     */
+    bool wp_inverted;
 };
 typedef struct SDHCIState SDHCIState;
 
-- 
2.34.1