[PATCH v2 3/7] i2c: designware: Move i2c_dw_validate_speed() helper to a common code

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

In order to export array supported speed for wider use, move it
to a header along with i2c_dw_validate_speed() helper moved to
a common code.

No functional changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v2: move it to common code instead of being separate (Jarkko)
 drivers/i2c/busses/i2c-designware-common.c  | 24 +++++++++++++++++
 drivers/i2c/busses/i2c-designware-core.h    |  9 +++++++
 drivers/i2c/busses/i2c-designware-platdrv.c | 29 ++++-----------------
 3 files changed, 38 insertions(+), 24 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index c70c6fc09ee3..9f06567be54a 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -116,6 +116,30 @@ int i2c_dw_set_reg_access(struct dw_i2c_dev *dev)
 	return 0;
 }
 
+int i2c_dw_validate_speed(struct dw_i2c_dev *dev)
+{
+	struct i2c_timings *t = &dev->timings;
+	unsigned int i;
+
+	/*
+	 * Only standard mode at 100kHz, fast mode at 400kHz,
+	 * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
+	 */
+	for (i = 0; i < ARRAY_SIZE(i2c_dw_supported_speeds); i++) {
+		if (t->bus_freq_hz == i2c_dw_supported_speeds[i])
+			break;
+	}
+	if (i == ARRAY_SIZE(i2c_dw_supported_speeds)) {
+		dev_err(dev->dev,
+			"%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
+			t->bus_freq_hz);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_validate_speed);
+
 u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset)
 {
 	/*
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 94d9ad15133a..77c8aa422268 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -359,3 +359,12 @@ extern int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev);
 #else
 static inline int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) { return 0; }
 #endif
+
+static __maybe_unused const u32 i2c_dw_supported_speeds[] = {
+	I2C_MAX_HIGH_SPEED_MODE_FREQ,
+	I2C_MAX_FAST_MODE_PLUS_FREQ,
+	I2C_MAX_FAST_MODE_FREQ,
+	I2C_MAX_STANDARD_MODE_FREQ,
+};
+
+int i2c_dw_validate_speed(struct dw_i2c_dev *dev);
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 7e228ff91ad4..a502750c89b7 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -192,13 +192,6 @@ static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 		pm_runtime_put_noidle(dev->dev);
 }
 
-static const u32 supported_speeds[] = {
-	I2C_MAX_HIGH_SPEED_MODE_FREQ,
-	I2C_MAX_FAST_MODE_PLUS_FREQ,
-	I2C_MAX_FAST_MODE_FREQ,
-	I2C_MAX_STANDARD_MODE_FREQ,
-};
-
 static int dw_i2c_plat_probe(struct platform_device *pdev)
 {
 	struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
@@ -241,11 +234,11 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	 * Some DSTDs use a non standard speed, round down to the lowest
 	 * standard speed.
 	 */
-	for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) {
-		if (acpi_speed >= supported_speeds[i])
+	for (i = 0; i < ARRAY_SIZE(i2c_dw_supported_speeds); i++) {
+		if (acpi_speed >= i2c_dw_supported_speeds[i])
 			break;
 	}
-	acpi_speed = i < ARRAY_SIZE(supported_speeds) ? supported_speeds[i] : 0;
+	acpi_speed = i < ARRAY_SIZE(i2c_dw_supported_speeds) ? i2c_dw_supported_speeds[i] : 0;
 
 	/*
 	 * Find bus speed from the "clock-frequency" device property, ACPI
@@ -266,21 +259,9 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	if (has_acpi_companion(&pdev->dev))
 		dw_i2c_acpi_configure(pdev);
 
-	/*
-	 * Only standard mode at 100kHz, fast mode at 400kHz,
-	 * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
-	 */
-	for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) {
-		if (t->bus_freq_hz == supported_speeds[i])
-			break;
-	}
-	if (i == ARRAY_SIZE(supported_speeds)) {
-		dev_err(&pdev->dev,
-			"%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
-			t->bus_freq_hz);
-		ret = -EINVAL;
+	ret = i2c_dw_validate_speed(dev);
+	if (ret)
 		goto exit_reset;
-	}
 
 	ret = i2c_dw_probe_lock_support(dev);
 	if (ret)
-- 
2.26.2