i2c: designware: add support for hcnt/lcnt got from dt

Add support for hcnt/lcnt got from dt. Signed-off-by: 因贤 <[email protected]>
guoren83 · Jun 12, 2024 · b9d4096 · b9d4096
1 parent cfdd65e
commit b9d4096
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diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
@@ -28,6 +28,8 @@
 
 #include "i2c-designware-core.h"
 
+#define I2C_DW_SDA_HOLD_DEFAULT	3
+
 static char *abort_sources[] = {
 	[ABRT_7B_ADDR_NOACK] =
 		"slave address not acknowledged (7bit mode)",
@@ -312,6 +314,31 @@ static u32 i2c_dw_acpi_round_bus_speed(struct device *device)
 
 static inline u32 i2c_dw_acpi_round_bus_speed(struct device *device) { return 0; }
 
+int i2c_dw_dt_configure(struct device *device)
+{
+	struct dw_i2c_dev *dev = dev_get_drvdata(device);
+	struct device_node *node = device->of_node;
+
+	/*
+	 * Try to get SDA hold time and *CNT values from an ACPI method for
+	 * selected speed modes.
+	 */
+	if (node) {
+		of_property_read_u16(node, "ss_hcnt", &dev->ss_hcnt);
+		of_property_read_u16(node, "ss_lcnt", &dev->ss_lcnt);
+		of_property_read_u16(node, "fp_hcnt", &dev->fp_hcnt);
+		of_property_read_u16(node, "fp_lcnt", &dev->fp_lcnt);
+		of_property_read_u16(node, "hs_hcnt", &dev->hs_hcnt);
+		of_property_read_u16(node, "hs_lcnt", &dev->hs_lcnt);
+		of_property_read_u16(node, "fs_hcnt", &dev->fs_hcnt);
+		of_property_read_u16(node, "fs_lcnt", &dev->fs_lcnt);
+		dev->sda_hold_time = I2C_DW_SDA_HOLD_DEFAULT;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_dt_configure);
+
 #endif	/* CONFIG_ACPI */
 
 void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev)

diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
@@ -398,6 +398,8 @@ void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev);
 
 #if IS_ENABLED(CONFIG_ACPI)
 int i2c_dw_acpi_configure(struct device *device);
+static inline int i2c_dw_dt_configure(struct device *device) { return -ENODEV; }
 #else
 static inline int i2c_dw_acpi_configure(struct device *device) { return -ENODEV; }
+int i2c_dw_dt_configure(struct device *device);
 #endif
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -316,6 +316,8 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 
 	if (has_acpi_companion(&pdev->dev))
 		i2c_dw_acpi_configure(&pdev->dev);
+	else
+		i2c_dw_dt_configure(&pdev->dev);
 
 	ret = i2c_dw_validate_speed(dev);
 	if (ret)