[PATCH v4 18/38] mmc: exynos_dw_mmc: Fix getting private data in exynos_dwmci_board_init()

[Sam Protsenko]

In case of CONFIG_DM_MMC, host->priv actually holds (struct udevice *),
and not (struct dwmci_exynos_priv_data *). This makes *priv pointer
invalid and may lead to Synchronous Abort during its dereference later
in exynos_dwmci_board_init(). Fix it by extracting
exynos_dwmmc_get_priv() helper from exynos_dwmci_clksel() and using it
for getting the private data in exynos_dwmci_board_init()

Fixes: 3537ee879e04 ("mmc: exynos_dw_mmc: support the Driver mode for Exynos")
Signed-off-by: Sam Protsenko <semen.protsenko at linaro.org>
---
Changes in v4:
  - (none)

Changes in v3:
  - (none)

Changes in v2:
  - (none)

 drivers/mmc/exynos_dw_mmc.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/exynos_dw_mmc.c b/drivers/mmc/exynos_dw_mmc.c
index a86d58663c1b..aa542c13fea8 100644
--- a/drivers/mmc/exynos_dw_mmc.c
+++ b/drivers/mmc/exynos_dw_mmc.c
@@ -41,18 +41,24 @@ struct dwmci_exynos_priv_data {
 	u32 sdr_timing;
 };
 
+static struct dwmci_exynos_priv_data *exynos_dwmmc_get_priv(
+		struct dwmci_host *host)
+{
+#ifdef CONFIG_DM_MMC
+	return container_of(host, struct dwmci_exynos_priv_data, host);
+#else
+	return host->priv;
+#endif
+}
+
 /*
  * Function used as callback function to initialise the
  * CLKSEL register for every mmc channel.
  */
 static int exynos_dwmci_clksel(struct dwmci_host *host)
 {
-#ifdef CONFIG_DM_MMC
-	struct dwmci_exynos_priv_data *priv =
-		container_of(host, struct dwmci_exynos_priv_data, host);
-#else
-	struct dwmci_exynos_priv_data *priv = host->priv;
-#endif
+	struct dwmci_exynos_priv_data *priv = exynos_dwmmc_get_priv(host);
+
 	dwmci_writel(host, DWMCI_CLKSEL, priv->sdr_timing);
 
 	return 0;
@@ -82,7 +88,7 @@ unsigned int exynos_dwmci_get_clk(struct dwmci_host *host, uint freq)
 
 static void exynos_dwmci_board_init(struct dwmci_host *host)
 {
-	struct dwmci_exynos_priv_data *priv = host->priv;
+	struct dwmci_exynos_priv_data *priv = exynos_dwmmc_get_priv(host);
 
 	if (host->quirks & DWMCI_QUIRK_DISABLE_SMU) {
 		dwmci_writel(host, EMMCP_MPSBEGIN0, 0);
-- 
2.39.2