soundwire: qcom: add support for mmio soundwire master devices

Adds support for qcom soundwire devices with memory mapped IO registers.
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200905173905.16541-4-jonathan@marek.caSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/qcom.c

@@ -34,6 +34,7 @@
 #define SWRM_INTERRUPT_STATUS_SPECIAL_CMD_ID_FINISHED		BIT(10)
 #define SWRM_INTERRUPT_MASK_ADDR				0x204
 #define SWRM_INTERRUPT_CLEAR					0x208
+#define SWRM_INTERRUPT_CPU_EN					0x210
 #define SWRM_CMD_FIFO_WR_CMD					0x300
 #define SWRM_CMD_FIFO_RD_CMD					0x304
 #define SWRM_CMD_FIFO_CMD					0x308
@@ -87,6 +88,7 @@ struct qcom_swrm_ctrl {
 	struct sdw_bus bus;
 	struct device *dev;
 	struct regmap *regmap;
+	void __iomem *mmio;
 	struct completion *comp;
 	struct work_struct slave_work;
 	/* read/write lock */
@@ -151,6 +153,20 @@ static int qcom_swrm_ahb_reg_write(struct qcom_swrm_ctrl *ctrl,
 	return SDW_CMD_OK;
 }
 
+static int qcom_swrm_cpu_reg_read(struct qcom_swrm_ctrl *ctrl, int reg,
+				  u32 *val)
+{
+	*val = readl(ctrl->mmio + reg);
+	return SDW_CMD_OK;
+}
+
+static int qcom_swrm_cpu_reg_write(struct qcom_swrm_ctrl *ctrl, int reg,
+				   int val)
+{
+	writel(val, ctrl->mmio + reg);
+	return SDW_CMD_OK;
+}
+
 static int qcom_swrm_cmd_fifo_wr_cmd(struct qcom_swrm_ctrl *ctrl, u8 cmd_data,
 				     u8 dev_addr, u16 reg_addr)
 {
@@ -305,6 +321,12 @@ static int qcom_swrm_init(struct qcom_swrm_ctrl *ctrl)
 	ctrl->reg_write(ctrl, SWRM_COMP_CFG_ADDR,
 			SWRM_COMP_CFG_IRQ_LEVEL_OR_PULSE_MSK |
 			SWRM_COMP_CFG_ENABLE_MSK);
+
+	/* enable CPU IRQs */
+	if (ctrl->mmio) {
+		ctrl->reg_write(ctrl, SWRM_INTERRUPT_CPU_EN,
+				SWRM_INTERRUPT_STATUS_RMSK);
+	}
 	return 0;
 }
 
@@ -756,8 +778,11 @@ static int qcom_swrm_probe(struct platform_device *pdev)
 		if (!ctrl->regmap)
 			return -EINVAL;
 	} else {
-		/* Only WCD based SoundWire controller is supported */
-		return -ENOTSUPP;
+		ctrl->reg_read = qcom_swrm_cpu_reg_read;
+		ctrl->reg_write = qcom_swrm_cpu_reg_write;
+		ctrl->mmio = devm_platform_ioremap_resource(pdev, 0);
+		if (IS_ERR(ctrl->mmio))
+			return PTR_ERR(ctrl->mmio);
 	}
 
 	ctrl->irq = of_irq_get(dev->of_node, 0);