diff --git a/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml b/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml
index 51534953a69cf..9401dc2d50522 100644
--- a/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml
+++ b/Documentation/devicetree/bindings/i2c/qcom,i2c-geni-qcom.yaml
@@ -60,6 +60,13 @@ properties:
   power-domains:
     maxItems: 1
 
+  qcom,qup-multi-owner:
+    type: boolean
+    description:
+      Indicates that the QUP-based controller is shared with one or more
+      other system processors and must not be assumed to have exclusive
+      ownership by the operating system.
+
   reg:
     maxItems: 1
 
diff --git a/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml b/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml
index 197f30b14d45e..0efe973488b9d 100644
--- a/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml
+++ b/Documentation/devicetree/bindings/input/focaltech,ft8112.yaml
@@ -20,6 +20,7 @@ properties:
   compatible:
     enum:
       - focaltech,ft8112
+      - focaltech,ft3d81
 
   reg:
     maxItems: 1
diff --git a/Documentation/devicetree/bindings/spi/qcom,spi-qcom-qspi.yaml b/Documentation/devicetree/bindings/spi/qcom,spi-qcom-qspi.yaml
index 1696ac46a660e..d9aac33b695bf 100644
--- a/Documentation/devicetree/bindings/spi/qcom,spi-qcom-qspi.yaml
+++ b/Documentation/devicetree/bindings/spi/qcom,spi-qcom-qspi.yaml
@@ -20,6 +20,7 @@ properties:
   compatible:
     items:
       - enum:
+          - qcom,qcs615-qspi
           - qcom,sc7180-qspi
           - qcom,sc7280-qspi
           - qcom,sdm845-qspi
diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c
index c9a6f610ffd9f..3cb20d854b00e 100644
--- a/drivers/dma/qcom/gpi.c
+++ b/drivers/dma/qcom/gpi.c
@@ -2,6 +2,7 @@
 /*
  * Copyright (c) 2017-2020, The Linux Foundation. All rights reserved.
  * Copyright (c) 2020, Linaro Limited
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
  */
 
 #include <dt-bindings/dma/qcom-gpi.h>
@@ -67,6 +68,14 @@
 #define TRE_DMA_LEN		GENMASK(23, 0)
 #define TRE_DMA_IMMEDIATE_LEN	GENMASK(3, 0)
 
+/* Lock TRE */
+#define TRE_LOCK		BIT(0)
+#define TRE_MINOR_TYPE		GENMASK(19, 16)
+#define TRE_MAJOR_TYPE		GENMASK(23, 20)
+
+/* Unlock TRE */
+#define TRE_UNLOCK		BIT(8)
+
 /* Register offsets from gpi-top */
 #define GPII_n_CH_k_CNTXT_0_OFFS(n, k)	(0x20000 + (0x4000 * (n)) + (0x80 * (k)))
 #define GPII_n_CH_k_CNTXT_0_EL_SIZE	GENMASK(31, 24)
@@ -518,7 +527,7 @@ struct gpii {
 	bool ieob_set;
 };
 
-#define MAX_TRE 3
+#define MAX_TRE 5
 
 struct gpi_desc {
 	struct virt_dma_desc vd;
@@ -1625,12 +1634,27 @@ static int gpi_create_i2c_tre(struct gchan *chan, struct gpi_desc *desc,
 			      unsigned long flags)
 {
 	struct gpi_i2c_config *i2c = chan->config;
+	enum gpi_lock_action lock_action = i2c->lock_action;
 	struct device *dev = chan->gpii->gpi_dev->dev;
 	unsigned int tre_idx = 0;
 	dma_addr_t address;
 	struct gpi_tre *tre;
 	unsigned int i;
 
+	/* Optional lock TRE before transfer */
+	if (lock_action == GPI_LOCK_ACQUIRE) {
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		tre->dword[0] = 0;
+		tre->dword[1] = 0;
+		tre->dword[2] = 0;
+		tre->dword[3] = u32_encode_bits(1, TRE_LOCK);
+		tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOB);
+		tre->dword[3] |= u32_encode_bits(0, TRE_MINOR_TYPE);
+		tre->dword[3] |= u32_encode_bits(3, TRE_MAJOR_TYPE);
+	}
+
 	/* first create config tre if applicable */
 	if (i2c->set_config) {
 		tre = &desc->tre[tre_idx];
@@ -1690,6 +1714,24 @@ static int gpi_create_i2c_tre(struct gchan *chan, struct gpi_desc *desc,
 
 		if (!(flags & DMA_PREP_INTERRUPT))
 			tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_BEI);
+
+		/* If multi-owner and this is the release boundary, chain it */
+		if (i2c->lock_action == GPI_LOCK_RELEASE)
+			tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
+	}
+
+	/* Optional unlock TRE after transfer */
+	if (lock_action == GPI_LOCK_RELEASE && i2c->op != I2C_READ) {
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		tre->dword[0] = 0;
+		tre->dword[1] = 0;
+		tre->dword[2] = 0;
+		tre->dword[3] = u32_encode_bits(1, TRE_UNLOCK);
+		tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOB);
+		tre->dword[3] |= u32_encode_bits(1, TRE_MINOR_TYPE);
+		tre->dword[3] |= u32_encode_bits(3, TRE_MAJOR_TYPE);
 	}
 
 	for (i = 0; i < tre_idx; i++)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index a482a4c60744a..0c52c57e739da 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -829,6 +829,14 @@ static int geni_i2c_gpi_xfer(struct geni_i2c_dev *gi2c, struct i2c_msg msgs[], i
 		if (i < num - 1)
 			peripheral.stretch = 1;
 
+		peripheral.lock_action = GPI_LOCK_NONE;
+		if (gi2c->se.multi_owner) {
+			if (i == 0)
+				peripheral.lock_action = GPI_LOCK_ACQUIRE;
+			else if (i == num - 1)
+				peripheral.lock_action = GPI_LOCK_RELEASE;
+		}
+
 		peripheral.addr = msgs[i].addr;
 		if (i > 0 && (!(msgs[i].flags & I2C_M_RD)))
 			peripheral.multi_msg = false;
@@ -1028,6 +1036,17 @@ static int geni_i2c_probe(struct platform_device *pdev)
 		gi2c->clk_freq_out = I2C_MAX_STANDARD_MODE_FREQ;
 	}
 
+	if (of_property_read_bool(pdev->dev.of_node, "qcom,qup-multi-owner")) {
+		/*
+		 * Multi-owner controller configuration: the controller may be
+		 * used by another system processor. Mark the SE as shared so
+		 * common GENI resource handling can avoid pin state changes
+		 * that would disrupt the other user.
+		 */
+		gi2c->se.multi_owner = true;
+		dev_dbg(&pdev->dev, "I2C controller is shared with another system processor\n");
+	}
+
 	if (has_acpi_companion(dev))
 		ACPI_COMPANION_SET(&gi2c->adap.dev, ACPI_COMPANION(dev));
 
@@ -1045,8 +1064,14 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	spin_lock_init(&gi2c->lock);
 	platform_set_drvdata(pdev, gi2c);
 
-	/* Keep interrupts disabled initially to allow for low-power modes */
-	ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq, IRQF_NO_AUTOEN,
+	/*
+	 * Keep interrupts disabled initially to allow for low-power modes.
+	 * IRQF_NO_SUSPEND: Keep IRQ enabled during suspend to handle I2C transfers
+	 *                  in noirq phase (e.g., from PCIe driver's noirq_resume).
+	 * IRQF_EARLY_RESUME: Enable IRQ early during resume sequence.
+	 */
+	ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq,
+			       IRQF_NO_AUTOEN | IRQF_NO_SUSPEND | IRQF_EARLY_RESUME,
 			       dev_name(dev), gi2c);
 	if (ret)
 		return dev_err_probe(dev, ret,
@@ -1103,7 +1128,9 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	}
 
 	if (fifo_disable) {
-		/* FIFO is disabled, so we can only use GPI DMA */
+		/* FIFO is disabled, so we can only use GPI DMA.
+		 * SE can be shared in GSI mode between subsystems, each SS owns a GPII.
+		 */
 		gi2c->gpi_mode = true;
 		ret = setup_gpi_dma(gi2c);
 		if (ret)
@@ -1112,6 +1139,10 @@ static int geni_i2c_probe(struct platform_device *pdev)
 		dev_dbg(dev, "Using GPI DMA mode for I2C\n");
 	} else {
 		gi2c->gpi_mode = false;
+
+		if (gi2c->se.multi_owner)
+			dev_err_probe(dev, -EINVAL, "I2C sharing not supported in non GSI mode\n");
+
 		tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
 
 		/* I2C Master Hub Serial Elements doesn't have the HW_PARAM_0 register */
@@ -1258,6 +1289,20 @@ static int __maybe_unused geni_i2c_suspend_noirq(struct device *dev)
 static int __maybe_unused geni_i2c_resume_noirq(struct device *dev)
 {
 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
+	int ret = 0;
+
+	/*
+	 * Resume hardware to handle I2C transfers from other drivers'
+	 * noirq_resume callbacks (e.g., PCIe driver).
+	 * pm_runtime_force_resume() properly handles PM state and usage_count.
+	 */
+	if (gi2c->suspended) {
+		ret = pm_runtime_force_resume(dev);
+		if (ret) {
+			dev_err(dev, "Failed to resume I2C during noirq: %d\n", ret);
+			return ret;
+		}
+	}
 
 	i2c_mark_adapter_resumed(&gi2c->adap);
 	return 0;
diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
index cd1779b6a91a7..1a60832ace168 100644
--- a/drivers/soc/qcom/qcom-geni-se.c
+++ b/drivers/soc/qcom/qcom-geni-se.c
@@ -597,10 +597,17 @@ int geni_se_resources_off(struct geni_se *se)
 
 	if (has_acpi_companion(se->dev))
 		return 0;
-
-	ret = pinctrl_pm_select_sleep_state(se->dev);
-	if (ret)
-		return ret;
+	/*
+	 * Select the "sleep" pinctrl state only when the serial engine is
+	 * exclusively owned by this system processor. For shared controller
+	 * configurations, another system processor may still be using the pins,
+	 * and switching them to "sleep" can disrupt ongoing transfers.
+	 */
+	if (!se->multi_owner) {
+		ret = pinctrl_pm_select_sleep_state(se->dev);
+		if (ret)
+			return ret;
+	}
 
 	geni_se_clks_off(se);
 	return 0;
diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c
index 7e39038160e00..624b3a7b62914 100644
--- a/drivers/spi/spi-qcom-qspi.c
+++ b/drivers/spi/spi-qcom-qspi.c
@@ -174,6 +174,7 @@ struct qcom_qspi {
 	void *virt_cmd_desc[QSPI_MAX_SG];
 	unsigned int n_cmd_desc;
 	struct icc_path *icc_path_cpu_to_qspi;
+	struct icc_path *icc_path_mem;
 	unsigned long last_speed;
 	/* Lock to protect data accessed by IRQs */
 	spinlock_t lock;
@@ -272,7 +273,7 @@ static void qcom_qspi_handle_err(struct spi_controller *host,
 static int qcom_qspi_set_speed(struct qcom_qspi *ctrl, unsigned long speed_hz)
 {
 	int ret;
-	unsigned int avg_bw_cpu;
+	unsigned int avg_bw_cpu, avg_bw_mem;
 
 	if (speed_hz == ctrl->last_speed)
 		return 0;
@@ -285,7 +286,7 @@ static int qcom_qspi_set_speed(struct qcom_qspi *ctrl, unsigned long speed_hz)
 	}
 
 	/*
-	 * Set BW quota for CPU.
+	 * Set BW quota for CPU and memory paths.
 	 * We don't have explicit peak requirement so keep it equal to avg_bw.
 	 */
 	avg_bw_cpu = Bps_to_icc(speed_hz);
@@ -296,6 +297,13 @@ static int qcom_qspi_set_speed(struct qcom_qspi *ctrl, unsigned long speed_hz)
 		return ret;
 	}
 
+	avg_bw_mem = Bps_to_icc(speed_hz);
+	ret = icc_set_bw(ctrl->icc_path_mem, avg_bw_mem, avg_bw_mem);
+	if (ret) {
+		dev_err(ctrl->dev, "ICC BW voting failed for memory: %d\n", ret);
+		return ret;
+	}
+
 	ctrl->last_speed = speed_hz;
 
 	return 0;
@@ -729,6 +737,11 @@ static int qcom_qspi_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, PTR_ERR(ctrl->icc_path_cpu_to_qspi),
 				     "Failed to get cpu path\n");
 
+	ctrl->icc_path_mem = devm_of_icc_get(dev, "qspi-memory");
+	if (IS_ERR(ctrl->icc_path_mem))
+		return dev_err_probe(dev, PTR_ERR(ctrl->icc_path_mem),
+				     "Failed to get memory path\n");
+
 	/* Set BW vote for register access */
 	ret = icc_set_bw(ctrl->icc_path_cpu_to_qspi, Bps_to_icc(1000),
 				Bps_to_icc(1000));
@@ -829,6 +842,13 @@ static int __maybe_unused qcom_qspi_runtime_suspend(struct device *dev)
 		return ret;
 	}
 
+	ret = icc_disable(ctrl->icc_path_mem);
+	if (ret) {
+		dev_err_ratelimited(ctrl->dev, "ICC disable failed for memory: %d\n", ret);
+		icc_enable(ctrl->icc_path_cpu_to_qspi);
+		return ret;
+	}
+
 	pinctrl_pm_select_sleep_state(dev);
 
 	return 0;
@@ -849,9 +869,19 @@ static int __maybe_unused qcom_qspi_runtime_resume(struct device *dev)
 		return ret;
 	}
 
+	ret = icc_enable(ctrl->icc_path_mem);
+	if (ret) {
+		dev_err_ratelimited(ctrl->dev, "ICC enable failed for memory: %d\n", ret);
+		icc_disable(ctrl->icc_path_cpu_to_qspi);
+		return ret;
+	}
+
 	ret = clk_bulk_prepare_enable(QSPI_NUM_CLKS, ctrl->clks);
-	if (ret)
+	if (ret) {
+		icc_disable(ctrl->icc_path_cpu_to_qspi);
+		icc_disable(ctrl->icc_path_mem);
 		return ret;
+	}
 
 	return dev_pm_opp_set_rate(dev, ctrl->last_speed * 4);
 }
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index b365dd5da3cb7..3c1be7b21290b 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -1031,8 +1031,20 @@ static void qcom_geni_serial_handle_tx_dma(struct uart_port *uport)
 {
 	struct qcom_geni_serial_port *port = to_dev_port(uport);
 	struct tty_port *tport = &uport->state->port;
+	unsigned int fifo_len = kfifo_len(&tport->xmit_fifo);
+
+	/*
+	 * Only advance the kfifo if it still contains the bytes that were
+	 * transferred. uart_flush_buffer() may have run before this IRQ
+	 * fired: it calls kfifo_reset() under the port lock, making
+	 * fifo_len = 0 while tx_remaining remains non-zero. Calling
+	 * uart_xmit_advance() in that case would underflow kfifo->out past
+	 * kfifo->in, making kfifo_len() wrap to UART_XMIT_SIZE - tx_remaining
+	 * and triggering a spurious large DMA transfer of stale data.
+	 */
+	if (fifo_len >= port->tx_remaining)
+		uart_xmit_advance(uport, port->tx_remaining);
 
-	uart_xmit_advance(uport, port->tx_remaining);
 	geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr, port->tx_remaining);
 	port->tx_dma_addr = 0;
 	port->tx_remaining = 0;
diff --git a/include/linux/dma/qcom-gpi-dma.h b/include/linux/dma/qcom-gpi-dma.h
index 332be28427e47..f10fa93713f96 100644
--- a/include/linux/dma/qcom-gpi-dma.h
+++ b/include/linux/dma/qcom-gpi-dma.h
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (c) 2020, Linaro Limited
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
  */
 
 #ifndef QCOM_GPI_DMA_H
@@ -54,6 +55,21 @@ enum i2c_op {
 	I2C_READ,
 };
 
+/**
+ * enum gpi_lock_action - request lock/unlock TRE sequencing
+ * @GPI_LOCK_NONE: No lock/unlock TRE requested for this transfer
+ * @GPI_LOCK_ACQUIRE: Emit a lock TRE before the transfer
+ * @GPI_LOCK_RELEASE: Emit an unlock TRE after the transfer
+ *
+ * Used by protocol drivers for multi-owner controller setups (e.g. when
+ * DeviceTree indicates the controller is shared via qcom,qup-multi-owner).
+ */
+enum gpi_lock_action {
+	GPI_LOCK_NONE = 0,
+	GPI_LOCK_ACQUIRE,
+	GPI_LOCK_RELEASE,
+};
+
 /**
  * struct gpi_i2c_config - i2c config for peripheral
  *
@@ -67,7 +83,8 @@ enum i2c_op {
  * @set_config: set peripheral config
  * @rx_len: receive length for buffer
  * @op: i2c cmd
- * @multi_msg: is part of multi i2c r-w msgs
+ * @muli-msg: is part of multi i2c r-w msgs
+ * @lock_action: request lock/unlock TRE sequencing for this transfer
  */
 struct gpi_i2c_config {
 	u8 set_config;
@@ -81,6 +98,7 @@ struct gpi_i2c_config {
 	u32 rx_len;
 	enum i2c_op op;
 	bool multi_msg;
+	enum gpi_lock_action lock_action;
 };
 
 #endif /* QCOM_GPI_DMA_H */
diff --git a/include/linux/soc/qcom/geni-se.h b/include/linux/soc/qcom/geni-se.h
index 0a984e2579fe2..326744e311cea 100644
--- a/include/linux/soc/qcom/geni-se.h
+++ b/include/linux/soc/qcom/geni-se.h
@@ -63,6 +63,7 @@ struct geni_icc_path {
  * @num_clk_levels:	Number of valid clock levels in clk_perf_tbl
  * @clk_perf_tbl:	Table of clock frequency input to serial engine clock
  * @icc_paths:		Array of ICC paths for SE
+ * @multi_owner:	True if SE is shared between multiprocessors.
  */
 struct geni_se {
 	void __iomem *base;
@@ -72,6 +73,7 @@ struct geni_se {
 	unsigned int num_clk_levels;
 	unsigned long *clk_perf_tbl;
 	struct geni_icc_path icc_paths[3];
+	bool multi_owner;
 };
 
 /* Common SE registers */