[PATCH v2] i2c: designware: platdrv: Set class based on dmi

[Ricardo Ribalda]

Current AMD's zen-based APUs use this core for some of its i2c-buses.

With this patch we re-enable autodetection of hwmon-alike devices, so
lm-sensors will be able to work automatically.

It does not affect the boot-time of embedded devices, as the class is
set based on the dmi information.

Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxx>
---
v2:
Changes by Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>:
 - CodeStyle
Changes by kernel test robot <lkp@xxxxxxxxx>
 - Include dmi header to fix build error on arc
 - check if dmi_get_system_info returned NULL
 drivers/i2c/busses/i2c-designware-platdrv.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index c2efaaaac252..5892fdba9c25 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -12,6 +12,7 @@
 #include <linux/clk-provider.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
+#include <linux/dmi.h>
 #include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/i2c.h>
@@ -173,6 +174,19 @@ static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 		pm_runtime_put_noidle(dev->dev);
 }
 
+static bool dw_i2c_hwmon_bus(void)
+{
+	const char *product_name = dmi_get_system_info(DMI_PRODUCT_NAME);
+
+	if (!product_name)
+		return false;
+
+	if (strstr(product_name, "QT5222"))
+		return true;
+
+	return false;
+}
+
 static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev->dev);
@@ -267,7 +281,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 
 	adap = &dev->adapter;
 	adap->owner = THIS_MODULE;
-	adap->class = I2C_CLASS_DEPRECATED;
+	adap->class = dw_i2c_hwmon_bus() ? I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 	adap->dev.of_node = pdev->dev.of_node;
 	adap->nr = -1;
-- 
2.27.0