diff mbox series

[v3,5/5] i2c: piix4: Clear remote IRR bit to get successive interrupt

Message ID 20240906071201.2254354-6-Shyam-sundar.S-k@amd.com
State New
Headers show
Series Introduce AMD ASF Controller Support to the i2c-piix4 driver | expand

Commit Message

Shyam Sundar S K Sept. 6, 2024, 7:12 a.m. UTC 
To ensure successive interrupts upon packet reception, it is necessary to
clear the remote IRR bit by writing the interrupt number to the EOI
register. The base address for this operation is provided by the BIOS and
retrieved by the driver by traversing the ASF object's namespace.

Co-developed-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
---
 drivers/i2c/busses/i2c-piix4.c | 11 +++++++++++
 1 file changed, 11 insertions(+)
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 6abbaeaf2810..bf79b2280613 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -188,6 +188,8 @@  struct sb800_mmio_cfg {
 };
 
 struct sb800_asf_data {
+	resource_size_t eoi_addr;
+	resource_size_t eoi_sz;
 	unsigned short addr;
 	int irq;
 };
@@ -199,6 +201,7 @@  enum piix4_algo {
 };
 
 struct i2c_piix4_adapdata {
+	void __iomem *eoi_base;
 	unsigned short smba;
 
 	/* SB800 */
@@ -1285,6 +1288,7 @@  static irqreturn_t sb800_asf_irq_handler(int irq, void *ptr)
 		sb800_asf_update_bits(piix4_smba, SB800_ASF_SLV_INTR, SMBHSTSTS, true);
 	}
 
+	iowrite32(irq, adapdata->eoi_base);
 	return IRQ_HANDLED;
 }
 
@@ -1322,6 +1326,10 @@  static int sb800_asf_add_adap(struct pci_dev *dev)
 		case IORESOURCE_IRQ:
 			data.irq = rentry->res->start;
 			break;
+		case IORESOURCE_MEM:
+			data.eoi_addr = rentry->res->start;
+			data.eoi_sz = resource_size(rentry->res);
+			break;
 		default:
 			dev_warn(&adev->dev, "Invalid ASF resource\n");
 			break;
@@ -1346,6 +1354,9 @@  static int sb800_asf_add_adap(struct pci_dev *dev)
 	}
 
 	INIT_DELAYED_WORK(&adapdata->work_buf, sb800_asf_process_slave);
+	adapdata->eoi_base = devm_ioremap(&dev->dev, data.eoi_addr, data.eoi_sz);
+	if (!adapdata->eoi_base)
+		return -ENOMEM;
 	adapdata->is_asf = true;
 	/* Increment the adapter count by 1 as ASF is added to the list */
 	piix4_adapter_count++;