[PATCH v3 04/11] i2c: npcm: Change the way of getting GCR regmap

[Tyrone Ting]

From: Tali Perry <tali.perry1 at gmail.com>

Change the way of getting NPCM system manager reigster (GCR)
and still maintain the old mechanism as a fallback if getting
nuvoton,sys-mgr fails while working with the legacy devicetree
file.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1 at gmail.com>
Signed-off-by: Tyrone Ting <kfting at nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 4c225e1a058f..fa12212b2428 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2236,6 +2236,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 	static struct regmap *clk_regmap;
 	int irq;
 	int ret;
+	struct device_node *np = pdev->dev.of_node;
 
 	bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
 	if (!bus)
@@ -2250,7 +2251,10 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 		return PTR_ERR(i2c_clk);
 	bus->apb_clk = clk_get_rate(i2c_clk);
 
-	gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+	gcr_regmap = syscon_regmap_lookup_by_phandle(np, "nuvoton,sys-mgr");
+	if (IS_ERR(gcr_regmap))
+		gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+
 	if (IS_ERR(gcr_regmap))
 		return PTR_ERR(gcr_regmap);
 	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
-- 
2.17.1