[PATCH master] gpio: rockchip: fix support for RK3588/RK3566

[Ahmad Fatoum]

The GPIO controller on newer Rockchip SoCs isn't compatible with the
older ones. Back when GPIOv2 support was added, RK3568 was the only
SoC supported using it, but since then support for the very similar
RK3566 as well as the newer RK3588 has followed, but the driver wasn't
extended to support them.

As GPIOv2 controllers have an identification register, start checking it
like Linux does and use that to detect whether we have a GPIOv2 or GPIOv1.

This issue was found trying to read GPIO inputs of the RK3566.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 drivers/gpio/gpio-rockchip.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c
index 7c67512ee380..2c13e97b9774 100644
--- a/drivers/gpio/gpio-rockchip.c
+++ b/drivers/gpio/gpio-rockchip.c
@@ -10,6 +10,10 @@
 #include <linux/basic_mmio_gpio.h>
 #include <mach/rockchip/rockchip.h>
 
+#define GPIO_TYPE_V1		(0)           /* GPIO Version ID reserved */
+#define GPIO_TYPE_V2		(0x01000C2B)  /* GPIO Version ID 0x01000C2B */
+#define GPIO_TYPE_V2_1		(0x0101157C)  /* GPIO Version ID 0x0101157C */
+
 struct rockchip_gpiochip {
 	struct device			*dev;
 	void __iomem			*reg_base;
@@ -131,6 +135,7 @@ static int rockchip_gpio_probe(struct device *dev)
 	struct gpio_chip *gpio;
 	struct resource *res;
 	void __iomem *reg_base;
+	u32 id, gpio_type;
 	int ret;
 
 	rgc = xzalloc(sizeof(*rgc));
@@ -153,7 +158,13 @@ static int rockchip_gpio_probe(struct device *dev)
 
 	reg_base = rgc->reg_base;
 
-	if (rockchip_soc() == 3568) {
+	id = readl(reg_base + 0x78);
+	if (id == GPIO_TYPE_V2 || id == GPIO_TYPE_V2_1)
+		gpio_type = GPIO_TYPE_V2;
+	else
+		gpio_type = GPIO_TYPE_V1;
+
+	if (gpio_type >= GPIO_TYPE_V2) {
 		gpio->ngpio = 32;
 		gpio->dev = dev;
 		gpio->ops = &rockchip_gpio_ops;
@@ -176,6 +187,9 @@ static int rockchip_gpio_probe(struct device *dev)
 		return ret;
 	}
 
+	dev_dbg(dev, "registered GPIOv%d-compatible bank\n",
+		gpio_type == GPIO_TYPE_V1 ? 1 : 2);
+
 	return 0;
 }
 
-- 
2.39.2