Add support for handling ASF slave process events as described in the AMD
ASF databook. This involves implementing the correct programming sequence
to manage each ASF packet appropriately.
Co-developed-by: Sanket Goswami <Sanket.Goswami@xxxxxxx>
Signed-off-by: Sanket Goswami <Sanket.Goswami@xxxxxxx>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
---
drivers/i2c/busses/i2c-amd-asf-plat.c | 103 ++++++++++++++++++++++++++
1 file changed, 103 insertions(+)
diff --git a/drivers/i2c/busses/i2c-amd-asf-plat.c b/drivers/i2c/busses/i2c-amd-asf-plat.c
index aa85e10a3927..1beef717ef40 100644
--- a/drivers/i2c/busses/i2c-amd-asf-plat.c
+++ b/drivers/i2c/busses/i2c-amd-asf-plat.c
@@ -29,13 +29,17 @@
#define ASF_CLK_EN 17
/* ASF address offsets */
+#define ASFINDEX (7 + piix4_smba)
#define ASFLISADDR (9 + piix4_smba)
#define ASFSTA (0xA + piix4_smba)
#define ASFSLVSTA (0xD + piix4_smba)
+#define ASFDATARWPTR (0x11 + piix4_smba)
+#define ASFSETDATARDPTR (0x12 + piix4_smba)
#define ASFDATABNKSEL (0x13 + piix4_smba)
#define ASFSLVEN (0x15 + piix4_smba)
#define ASF_BLOCK_MAX_BYTES 72
+#define ASF_ERROR_STATUS 0xE
static const char *amd_asf_port_name = " port 1";
@@ -43,10 +47,71 @@ struct amd_asf_dev {
struct i2c_adapter adap;
struct device *dev;
struct i2c_client *target;
+ struct delayed_work work_buf;
struct sb800_mmio_cfg mmio_cfg;
struct resource *port_addr;
};
+static void amd_asf_process_target(struct work_struct *work)
+{
+ struct amd_asf_dev *dev = container_of(work, struct amd_asf_dev, work_buf.work);
+ unsigned short piix4_smba = dev->port_addr->start;
+ u8 data[ASF_BLOCK_MAX_BYTES];
+ u8 len, idx, val = 0;
+ u8 bank, reg, cmd;
+
+ /* Read target status register */
+ reg = inb_p(ASFSLVSTA);
+
+ /* Check if no error bits are set in target status register */
+ if (reg & ASF_ERROR_STATUS) {
+ /* Set bank as full */
+ cmd = 0;
+ reg = reg | GENMASK(3, 2);
+ outb_p(reg, ASFDATABNKSEL);
+ } else {
+ /* Read data bank */
+ reg = inb_p(ASFDATABNKSEL);
+ bank = (reg & BIT(3)) ? 1 : 0;
+
+ /* Set read data bank */
+ if (bank) {
+ reg = reg | BIT(4);
+ reg = reg & ~BIT(3);
+ } else {
+ reg = reg & ~BIT(4);
+ reg = reg & ~BIT(2);
+ }
+
+ /* Read command register */
+ outb_p(reg, ASFDATABNKSEL);
+ cmd = inb_p(ASFINDEX);
+ len = inb_p(ASFDATARWPTR);
+ for (idx = 0; idx < len; idx++)
+ data[idx] = inb_p(ASFINDEX);
+
+ /* Clear data bank status */
+ if (bank) {
+ reg = reg | BIT(3);
+ outb_p(reg, ASFDATABNKSEL);
+ } else {
+ reg = reg | BIT(2);
+ outb_p(reg, ASFDATABNKSEL);
+ }
+ }
+
+ outb_p(0, ASFSETDATARDPTR);
+ if (cmd & BIT(0))
+ return;
+
+ i2c_slave_event(dev->target, I2C_SLAVE_WRITE_REQUESTED, &val);
+ for (idx = 0; idx < len; idx++) {
+ val = data[idx];
+ i2c_slave_event(dev->target, I2C_SLAVE_WRITE_RECEIVED, &val);
+ }
+ i2c_slave_event(dev->target, I2C_SLAVE_STOP, &val);
+}
+
static void amd_asf_update_bits(unsigned short piix4_smba, u8 bit,
unsigned long offset, bool set)
{
@@ -212,9 +277,28 @@ static const struct i2c_algorithm amd_asf_smbus_algorithm = {
.functionality = amd_asf_func,
};
+static irqreturn_t amd_asf_irq_handler(int irq, void *ptr)
+{
+ struct amd_asf_dev *dev = ptr;
+ unsigned short piix4_smba = dev->port_addr->start;
+ u8 target_int = inb_p(ASFSTA);
+
+ if (target_int & BIT(6)) {
+ /* Target Interrupt */
+ outb_p(target_int | BIT(6), ASFSTA);
+ schedule_delayed_work(&dev->work_buf, HZ);
+ } else {
+ /* Controller Interrupt */
+ amd_asf_update_bits(piix4_smba, ASF_SLV_INTR, SMBHSTSTS, true);
+ }
+
+ return IRQ_HANDLED;
+}
+
static int amd_asf_probe(struct platform_device *pdev)
{
struct amd_asf_dev *asf_dev;
+ int ret, irq;
asf_dev = devm_kzalloc(&pdev->dev, sizeof(*asf_dev), GFP_KERNEL);
if (!asf_dev)
@@ -228,6 +312,17 @@ static int amd_asf_probe(struct platform_device *pdev)
if (!asf_dev->port_addr)
return dev_err_probe(&pdev->dev, -EINVAL, "missing IO resources\n");
+ INIT_DELAYED_WORK(&asf_dev->work_buf, amd_asf_process_target);
+
+ irq = platform_get_irq(pdev, 0);
+ if (!irq)
+ return dev_err_probe(&pdev->dev, -EINVAL, "missing IRQ resources\n");
+
+ ret = devm_request_irq(&pdev->dev, irq, amd_asf_irq_handler, IRQF_SHARED,
+ "amd_smbus_asf", asf_dev);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "Unable to request irq: %d for use\n", irq);
+
asf_dev->adap.owner = THIS_MODULE;
asf_dev->adap.algo = &amd_asf_smbus_algorithm;
asf_dev->adap.dev.parent = &pdev->dev;
@@ -239,6 +334,13 @@ static int amd_asf_probe(struct platform_device *pdev)
return devm_i2c_add_adapter(&pdev->dev, &asf_dev->adap);
}
+static void amd_asf_remove(struct platform_device *pdev)
+{
+ struct amd_asf_dev *dev = platform_get_drvdata(pdev);
+
+ cancel_delayed_work_sync(&dev->work_buf);
+}
+
static const struct acpi_device_id amd_asf_acpi_ids[] = {
{ "AMDI001A" },
{ }
@@ -251,6 +353,7 @@ static struct platform_driver amd_asf_driver = {
.acpi_match_table = amd_asf_acpi_ids,
},
.probe = amd_asf_probe,
+ .remove_new = amd_asf_remove,
};
module_platform_driver(amd_asf_driver);
--
2.25.1
