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-rw-r--r--drivers/i2c/busses/i2c-i801.c99
-rw-r--r--drivers/i2c/busses/i2c-octeon.c17
-rw-r--r--drivers/i2c/muxes/i2c-mux-reg.c1
3 files changed, 107 insertions, 10 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 64b1208bca5e..4a60ad214747 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -245,6 +245,13 @@ struct i801_priv {
struct platform_device *mux_pdev;
#endif
struct platform_device *tco_pdev;
+
+ /*
+ * If set to true the host controller registers are reserved for
+ * ACPI AML use. Protected by acpi_lock.
+ */
+ bool acpi_reserved;
+ struct mutex acpi_lock;
};
#define FEATURE_SMBUS_PEC (1 << 0)
@@ -718,6 +725,12 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
int ret = 0, xact = 0;
struct i801_priv *priv = i2c_get_adapdata(adap);
+ mutex_lock(&priv->acpi_lock);
+ if (priv->acpi_reserved) {
+ mutex_unlock(&priv->acpi_lock);
+ return -EBUSY;
+ }
+
pm_runtime_get_sync(&priv->pci_dev->dev);
hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
@@ -820,6 +833,7 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
out:
pm_runtime_mark_last_busy(&priv->pci_dev->dev);
pm_runtime_put_autosuspend(&priv->pci_dev->dev);
+ mutex_unlock(&priv->acpi_lock);
return ret;
}
@@ -1257,6 +1271,83 @@ static void i801_add_tco(struct i801_priv *priv)
priv->tco_pdev = pdev;
}
+#ifdef CONFIG_ACPI
+static acpi_status
+i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
+ u64 *value, void *handler_context, void *region_context)
+{
+ struct i801_priv *priv = handler_context;
+ struct pci_dev *pdev = priv->pci_dev;
+ acpi_status status;
+
+ /*
+ * Once BIOS AML code touches the OpRegion we warn and inhibit any
+ * further access from the driver itself. This device is now owned
+ * by the system firmware.
+ */
+ mutex_lock(&priv->acpi_lock);
+
+ if (!priv->acpi_reserved) {
+ priv->acpi_reserved = true;
+
+ dev_warn(&pdev->dev, "BIOS is accessing SMBus registers\n");
+ dev_warn(&pdev->dev, "Driver SMBus register access inhibited\n");
+
+ /*
+ * BIOS is accessing the host controller so prevent it from
+ * suspending automatically from now on.
+ */
+ pm_runtime_get_sync(&pdev->dev);
+ }
+
+ if ((function & ACPI_IO_MASK) == ACPI_READ)
+ status = acpi_os_read_port(address, (u32 *)value, bits);
+ else
+ status = acpi_os_write_port(address, (u32)*value, bits);
+
+ mutex_unlock(&priv->acpi_lock);
+
+ return status;
+}
+
+static int i801_acpi_probe(struct i801_priv *priv)
+{
+ struct acpi_device *adev;
+ acpi_status status;
+
+ adev = ACPI_COMPANION(&priv->pci_dev->dev);
+ if (adev) {
+ status = acpi_install_address_space_handler(adev->handle,
+ ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler,
+ NULL, priv);
+ if (ACPI_SUCCESS(status))
+ return 0;
+ }
+
+ return acpi_check_resource_conflict(&priv->pci_dev->resource[SMBBAR]);
+}
+
+static void i801_acpi_remove(struct i801_priv *priv)
+{
+ struct acpi_device *adev;
+
+ adev = ACPI_COMPANION(&priv->pci_dev->dev);
+ if (!adev)
+ return;
+
+ acpi_remove_address_space_handler(adev->handle,
+ ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler);
+
+ mutex_lock(&priv->acpi_lock);
+ if (priv->acpi_reserved)
+ pm_runtime_put(&priv->pci_dev->dev);
+ mutex_unlock(&priv->acpi_lock);
+}
+#else
+static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; }
+static inline void i801_acpi_remove(struct i801_priv *priv) { }
+#endif
+
static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
unsigned char temp;
@@ -1274,6 +1365,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
priv->adapter.dev.parent = &dev->dev;
ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev));
priv->adapter.retries = 3;
+ mutex_init(&priv->acpi_lock);
priv->pci_dev = dev;
switch (dev->device) {
@@ -1336,10 +1428,8 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
return -ENODEV;
}
- err = acpi_check_resource_conflict(&dev->resource[SMBBAR]);
- if (err) {
+ if (i801_acpi_probe(priv))
return -ENODEV;
- }
err = pcim_iomap_regions(dev, 1 << SMBBAR,
dev_driver_string(&dev->dev));
@@ -1348,6 +1438,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
"Failed to request SMBus region 0x%lx-0x%Lx\n",
priv->smba,
(unsigned long long)pci_resource_end(dev, SMBBAR));
+ i801_acpi_remove(priv);
return err;
}
@@ -1412,6 +1503,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
err = i2c_add_adapter(&priv->adapter);
if (err) {
dev_err(&dev->dev, "Failed to add SMBus adapter\n");
+ i801_acpi_remove(priv);
return err;
}
@@ -1438,6 +1530,7 @@ static void i801_remove(struct pci_dev *dev)
i801_del_mux(priv);
i2c_del_adapter(&priv->adapter);
+ i801_acpi_remove(priv);
pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
platform_device_unregister(priv->tco_pdev);
diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
index aa5f01efd826..30ae35146723 100644
--- a/drivers/i2c/busses/i2c-octeon.c
+++ b/drivers/i2c/busses/i2c-octeon.c
@@ -934,8 +934,15 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
return result;
for (i = 0; i < length; i++) {
- /* for the last byte TWSI_CTL_AAK must not be set */
- if (i + 1 == length)
+ /*
+ * For the last byte to receive TWSI_CTL_AAK must not be set.
+ *
+ * A special case is I2C_M_RECV_LEN where we don't know the
+ * additional length yet. If recv_len is set we assume we're
+ * not reading the final byte and therefore need to set
+ * TWSI_CTL_AAK.
+ */
+ if ((i + 1 == length) && !(recv_len && i == 0))
final_read = true;
/* clear iflg to allow next event */
@@ -950,12 +957,8 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
data[i] = octeon_i2c_data_read(i2c);
if (recv_len && i == 0) {
- if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
- dev_err(i2c->dev,
- "%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
- __func__, data[i]);
+ if (data[i] > I2C_SMBUS_BLOCK_MAX + 1)
return -EPROTO;
- }
length += data[i];
}
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
index 6773cadf7c9f..26e7c5187a58 100644
--- a/drivers/i2c/muxes/i2c-mux-reg.c
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -260,6 +260,7 @@ static struct platform_driver i2c_mux_reg_driver = {
.remove = i2c_mux_reg_remove,
.driver = {
.name = "i2c-mux-reg",
+ .of_match_table = of_match_ptr(i2c_mux_reg_of_match),
},
};
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-16 14:15:39 +0000