This patch makes some constants SoC-dependent to support more watchdogs
in the future. It adds shifts of WDT_MODE_KEY and SWSYSRST_KEY to
mtk_wdt_data struct. This is done to bring support for various Mediatek
watchdogs which use same register structure but slightly different field
offsets in the UNLOCK_KEY registers. For example, mt6577 watchdog has
WDT_MODE_KEY and SWSYSRST_KEY at [15:8] instead of currently (and only)
supported [31:24].
Moreover, this patch adds SWSYSRST_KEY value to mtk_wdt_data because this
value also depends on specific SoC watchdog, for example mt6577 uses 0x15
instead of 0x88.

Signed-off-by: Boris Lysov <redacted>
---
  drivers/watchdog/mtk_wdt.c | 76 ++++++++++++++++++++++++++++----------
  1 file changed, 57 insertions(+), 19 deletions(-)

diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
index 97ca993bd009..9d3091b12c06 100644
--- a/drivers/watchdog/mtk_wdt.c
+++ b/drivers/watchdog/mtk_wdt.c

@@ -44,13 +44,27 @@
  #define WDT_MODE_IRQ_EN		(1 << 3)
  #define WDT_MODE_AUTO_START	(1 << 4)
  #define WDT_MODE_DUAL_EN	(1 << 6)
-#define WDT_MODE_KEY		0x22000000
+#define WDT_MODE_KEY		0x22
  
  #define WDT_SWRST		0x14
  #define WDT_SWRST_KEY		0x1209
-
  #define WDT_SWSYSRST		0x18U
-#define WDT_SWSYS_RST_KEY	0x88000000
+
+#define MT2712_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT2712_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT2712_SWSYSRST_KEY		0x88
+
+#define MT6589_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT6589_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT6589_SWSYSRST_KEY		0x88
+
+#define MT8183_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT8183_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT8183_SWSYSRST_KEY		0x88
+
+#define MT8192_WDT_MODE_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT8192_SWSYSRST_KEY_SHIFT	24		// unlock_key [31:24]
+#define MT8192_SWSYSRST_KEY		0x88
  
  #define DRV_NAME		"mtk-wdt"
  #define DRV_VERSION		"1.0"

@@ -60,6 +74,7 @@ static unsigned int timeout;
  
  struct mtk_wdt_dev {
  	struct watchdog_device wdt_dev;
+	const struct mtk_wdt_data *data;
  	void __iomem *wdt_base;
  	spinlock_t lock; /* protects WDT_SWSYSRST reg */
  	struct reset_controller_dev rcdev;

@@ -67,18 +82,37 @@ struct mtk_wdt_dev {
  
  struct mtk_wdt_data {
  	int toprgu_sw_rst_num;
+	u8 wdt_mode_key_shift;
+	u8 wdt_swsys_rst_key;
+	u8 wdt_swsys_rst_key_shift;
  };
  
  static const struct mtk_wdt_data mt2712_data = {
-	.toprgu_sw_rst_num = MT2712_TOPRGU_SW_RST_NUM,
+	.toprgu_sw_rst_num =		MT2712_TOPRGU_SW_RST_NUM,
+	.wdt_mode_key_shift =		MT2712_WDT_MODE_KEY_SHIFT,
+	.wdt_swsys_rst_key_shift =	MT2712_SWSYSRST_KEY_SHIFT,
+	.wdt_swsys_rst_key =		MT2712_SWSYSRST_KEY,
+};
+
+static const struct mtk_wdt_data mt6589_data = {
+	.toprgu_sw_rst_num =		-1,
+	.wdt_mode_key_shift =		MT6589_WDT_MODE_KEY_SHIFT,
+	.wdt_swsys_rst_key_shift =	MT6589_SWSYSRST_KEY_SHIFT,
+	.wdt_swsys_rst_key =		MT6589_SWSYSRST_KEY,
  };
  
  static const struct mtk_wdt_data mt8183_data = {
-	.toprgu_sw_rst_num = MT8183_TOPRGU_SW_RST_NUM,
+	.toprgu_sw_rst_num =		MT8183_TOPRGU_SW_RST_NUM,
+	.wdt_mode_key_shift =		MT8183_WDT_MODE_KEY_SHIFT,
+	.wdt_swsys_rst_key_shift =	MT8183_SWSYSRST_KEY_SHIFT,
+	.wdt_swsys_rst_key =		MT8183_SWSYSRST_KEY,
  };
  
  static const struct mtk_wdt_data mt8192_data = {
-	.toprgu_sw_rst_num = MT8192_TOPRGU_SW_RST_NUM,
+	.toprgu_sw_rst_num =		MT8192_TOPRGU_SW_RST_NUM,
+	.wdt_mode_key_shift =		MT8192_WDT_MODE_KEY_SHIFT,
+	.wdt_swsys_rst_key_shift =	MT8192_SWSYSRST_KEY_SHIFT,
+	.wdt_swsys_rst_key =		MT8192_SWSYSRST_KEY,
  };
  
  static int toprgu_reset_update(struct reset_controller_dev *rcdev,

@@ -86,20 +120,20 @@ static int toprgu_reset_update(struct reset_controller_dev *rcdev,
  {
  	unsigned int tmp;
  	unsigned long flags;
-	struct mtk_wdt_dev *data =
+	struct mtk_wdt_dev *wdev =