[PATCH v3 2/2] ASoC: qcom: soundwire: Add software clock gating requirement check

[Srinivasa Rao Mandadapu <quic_srivasam@xxxxxxxxxxx>]

Validate software clock gating required or not and do software
clock gating on hclk if soundwire is operational and keep it
running by adding flag in private dat structure.
This is to avoid conflict between older architectures,
where software clock gating is not required and on latest
architectues, where software clock gating is mandatory.

Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@xxxxxxxxxxx>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
 drivers/soundwire/qcom.c | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index 38c3bf5..ebd7479 100644
--- a/drivers/soundwire/qcom.c
+++ b/drivers/soundwire/qcom.c
@@ -194,6 +194,12 @@ static const struct qcom_swrm_data swrm_v1_5_data = {
 	.default_cols = 16,
 };
 
+static const struct qcom_swrm_data swrm_v1_6_data = {
+	.default_rows = 50,
+	.default_cols = 16,
+	.sw_clk_gate_required = true,
+};
+
 #define to_qcom_sdw(b)	container_of(b, struct qcom_swrm_ctrl, bus)
 
 static int qcom_swrm_ahb_reg_read(struct qcom_swrm_ctrl *ctrl, int reg,
@@ -659,7 +665,8 @@ static int qcom_swrm_init(struct qcom_swrm_ctrl *ctrl)
 	val = FIELD_PREP(SWRM_MCP_FRAME_CTRL_BANK_ROW_CTRL_BMSK, ctrl->rows_index);
 	val |= FIELD_PREP(SWRM_MCP_FRAME_CTRL_BANK_COL_CTRL_BMSK, ctrl->cols_index);
 
-	reset_control_reset(ctrl->audio_cgcr);
+	if (ctrl->audio_cgcr)
+		reset_control_reset(ctrl->audio_cgcr);
 
 	ctrl->reg_write(ctrl, SWRM_MCP_FRAME_CTRL_BANK_ADDR(0), val);
 
@@ -1312,6 +1319,15 @@ static int qcom_swrm_probe(struct platform_device *pdev)
 			return PTR_ERR(ctrl->mmio);
 	}
 
+	if (data->sw_clk_gate_required) {
+		ctrl->audio_cgcr = devm_reset_control_get_exclusive(dev, "swr_audio_cgcr");
+		if (IS_ERR(ctrl->audio_cgcr)) {
+			dev_err(dev, "Failed to get cgcr reset ctrl required for SW gating\n");
+			ret = PTR_ERR(ctrl->audio_cgcr);
+			goto err_init;
+		}
+	}
+
 	ctrl->irq = of_irq_get(dev->of_node, 0);
 	if (ctrl->irq < 0) {
 		ret = ctrl->irq;
@@ -1337,10 +1353,6 @@ static int qcom_swrm_probe(struct platform_device *pdev)
 	ctrl->bus.compute_params = &qcom_swrm_compute_params;
 	ctrl->bus.clk_stop_timeout = 300;
 
-	ctrl->audio_cgcr = devm_reset_control_get_exclusive(dev, "swr_audio_cgcr");
-	if (IS_ERR(ctrl->audio_cgcr))
-		dev_err(dev, "Failed to get audio_cgcr reset required for soundwire-v1.6.0\n");
-
 	ret = qcom_swrm_get_port_config(ctrl);
 	if (ret)
 		goto err_clk;
@@ -1494,7 +1506,8 @@ static int __maybe_unused swrm_runtime_resume(struct device *dev)
 		qcom_swrm_get_device_status(ctrl);
 		sdw_handle_slave_status(&ctrl->bus, ctrl->status);
 	} else {
-		reset_control_reset(ctrl->audio_cgcr);
+		if (ctrl->audio_cgcr)
+			reset_control_reset(ctrl->audio_cgcr);
 
 		ctrl->reg_write(ctrl, SWRM_MCP_BUS_CTRL, SWRM_MCP_BUS_CLK_START);
 		ctrl->reg_write(ctrl, SWRM_INTERRUPT_CLEAR,
@@ -1559,7 +1572,7 @@ static const struct dev_pm_ops swrm_dev_pm_ops = {
 static const struct of_device_id qcom_swrm_of_match[] = {
 	{ .compatible = "qcom,soundwire-v1.3.0", .data = &swrm_v1_3_data },
 	{ .compatible = "qcom,soundwire-v1.5.1", .data = &swrm_v1_5_data },
-	{ .compatible = "qcom,soundwire-v1.6.0", .data = &swrm_v1_5_data },
+	{ .compatible = "qcom,soundwire-v1.6.0", .data = &swrm_v1_6_data },
 	{/* sentinel */},
 };
 
-- 
2.7.4