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path: root/drivers/i2c/busses/i2c-i801.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-i801.c')
-rw-r--r--drivers/i2c/busses/i2c-i801.c251
1 files changed, 236 insertions, 15 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 64b1208bca5e..5ef9b733d153 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -72,6 +72,7 @@
* Block process call transaction no
* I2C block read transaction yes (doesn't use the block buffer)
* Slave mode no
+ * SMBus Host Notify yes
* Interrupt processing yes
*
* See the file Documentation/i2c/busses/i2c-i801 for details.
@@ -86,6 +87,7 @@
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/dmi.h>
@@ -96,8 +98,7 @@
#include <linux/platform_data/itco_wdt.h>
#include <linux/pm_runtime.h>
-#if (defined CONFIG_I2C_MUX_GPIO || defined CONFIG_I2C_MUX_GPIO_MODULE) && \
- defined CONFIG_DMI
+#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
#include <linux/gpio.h>
#include <linux/i2c-mux-gpio.h>
#endif
@@ -113,6 +114,10 @@
#define SMBPEC(p) (8 + (p)->smba) /* ICH3 and later */
#define SMBAUXSTS(p) (12 + (p)->smba) /* ICH4 and later */
#define SMBAUXCTL(p) (13 + (p)->smba) /* ICH4 and later */
+#define SMBSLVSTS(p) (16 + (p)->smba) /* ICH3 and later */
+#define SMBSLVCMD(p) (17 + (p)->smba) /* ICH3 and later */
+#define SMBNTFDADD(p) (20 + (p)->smba) /* ICH3 and later */
+#define SMBNTFDDAT(p) (22 + (p)->smba) /* ICH3 and later */
/* PCI Address Constants */
#define SMBBAR 4
@@ -144,6 +149,10 @@
/* TCO configuration bits for TCOCTL */
#define TCOCTL_EN 0x0100
+/* Auxiliary status register bits, ICH4+ only */
+#define SMBAUXSTS_CRCE 1
+#define SMBAUXSTS_STCO 2
+
/* Auxiliary control register bits, ICH4+ only */
#define SMBAUXCTL_CRC 1
#define SMBAUXCTL_E32B 2
@@ -177,6 +186,12 @@
#define SMBHSTSTS_INTR 0x02
#define SMBHSTSTS_HOST_BUSY 0x01
+/* Host Notify Status registers bits */
+#define SMBSLVSTS_HST_NTFY_STS 1
+
+/* Host Notify Command registers bits */
+#define SMBSLVCMD_HST_NTFY_INTREN 0x01
+
#define STATUS_ERROR_FLAGS (SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \
SMBHSTSTS_DEV_ERR)
@@ -239,19 +254,29 @@ struct i801_priv {
int len;
u8 *data;
-#if (defined CONFIG_I2C_MUX_GPIO || defined CONFIG_I2C_MUX_GPIO_MODULE) && \
- defined CONFIG_DMI
+#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
const struct i801_mux_config *mux_drvdata;
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;
+ struct smbus_host_notify *host_notify;
};
+#define SMBHSTNTFY_SIZE 8
+
#define FEATURE_SMBUS_PEC (1 << 0)
#define FEATURE_BLOCK_BUFFER (1 << 1)
#define FEATURE_BLOCK_PROC (1 << 2)
#define FEATURE_I2C_BLOCK_READ (1 << 3)
#define FEATURE_IRQ (1 << 4)
+#define FEATURE_HOST_NOTIFY (1 << 5)
/* Not really a feature, but it's convenient to handle it as such */
#define FEATURE_IDF (1 << 15)
#define FEATURE_TCO (1 << 16)
@@ -262,6 +287,7 @@ static const char *i801_feature_names[] = {
"Block process call",
"I2C block read",
"Interrupt",
+ "SMBus Host Notify",
};
static unsigned int disable_features;
@@ -270,7 +296,8 @@ MODULE_PARM_DESC(disable_features, "Disable selected driver features:\n"
"\t\t 0x01 disable SMBus PEC\n"
"\t\t 0x02 disable the block buffer\n"
"\t\t 0x08 disable the I2C block read functionality\n"
- "\t\t 0x10 don't use interrupts ");
+ "\t\t 0x10 don't use interrupts\n"
+ "\t\t 0x20 disable SMBus Host Notify ");
/* Make sure the SMBus host is ready to start transmitting.
Return 0 if it is, -EBUSY if it is not. */
@@ -298,6 +325,29 @@ static int i801_check_pre(struct i801_priv *priv)
}
}
+ /*
+ * Clear CRC status if needed.
+ * During normal operation, i801_check_post() takes care
+ * of it after every operation. We do it here only in case
+ * the hardware was already in this state when the driver
+ * started.
+ */
+ if (priv->features & FEATURE_SMBUS_PEC) {
+ status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE;
+ if (status) {
+ dev_dbg(&priv->pci_dev->dev,
+ "Clearing aux status flags (%02x)\n", status);
+ outb_p(status, SMBAUXSTS(priv));
+ status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE;
+ if (status) {
+ dev_err(&priv->pci_dev->dev,
+ "Failed clearing aux status flags (%02x)\n",
+ status);
+ return -EBUSY;
+ }
+ }
+ }
+
return 0;
}
@@ -341,8 +391,30 @@ static int i801_check_post(struct i801_priv *priv, int status)
dev_err(&priv->pci_dev->dev, "Transaction failed\n");
}
if (status & SMBHSTSTS_DEV_ERR) {
- result = -ENXIO;
- dev_dbg(&priv->pci_dev->dev, "No response\n");
+ /*
+ * This may be a PEC error, check and clear it.
+ *
+ * AUXSTS is handled differently from HSTSTS.
+ * For HSTSTS, i801_isr() or i801_wait_intr()
+ * has already cleared the error bits in hardware,
+ * and we are passed a copy of the original value
+ * in "status".
+ * For AUXSTS, the hardware register is left
+ * for us to handle here.
+ * This is asymmetric, slightly iffy, but safe,
+ * since all this code is serialized and the CRCE
+ * bit is harmless as long as it's cleared before
+ * the next operation.
+ */
+ if ((priv->features & FEATURE_SMBUS_PEC) &&
+ (inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE)) {
+ outb_p(SMBAUXSTS_CRCE, SMBAUXSTS(priv));
+ result = -EBADMSG;
+ dev_dbg(&priv->pci_dev->dev, "PEC error\n");
+ } else {
+ result = -ENXIO;
+ dev_dbg(&priv->pci_dev->dev, "No response\n");
+ }
}
if (status & SMBHSTSTS_BUS_ERR) {
result = -EAGAIN;
@@ -504,8 +576,23 @@ static void i801_isr_byte_done(struct i801_priv *priv)
outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv));
}
+static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)
+{
+ unsigned short addr;
+ unsigned int data;
+
+ addr = inb_p(SMBNTFDADD(priv)) >> 1;
+ data = inw_p(SMBNTFDDAT(priv));
+
+ i2c_handle_smbus_host_notify(priv->host_notify, addr, data);
+
+ /* clear Host Notify bit and return */
+ outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
+ return IRQ_HANDLED;
+}
+
/*
- * There are two kinds of interrupts:
+ * There are three kinds of interrupts:
*
* 1) i801 signals transaction completion with one of these interrupts:
* INTR - Success
@@ -517,6 +604,8 @@ static void i801_isr_byte_done(struct i801_priv *priv)
*
* 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt
* occurs for each byte of a byte-by-byte to prepare the next byte.
+ *
+ * 3) Host Notify interrupts
*/
static irqreturn_t i801_isr(int irq, void *dev_id)
{
@@ -529,6 +618,12 @@ static irqreturn_t i801_isr(int irq, void *dev_id)
if (!(pcists & SMBPCISTS_INTS))
return IRQ_NONE;
+ if (priv->features & FEATURE_HOST_NOTIFY) {
+ status = inb_p(SMBSLVSTS(priv));
+ if (status & SMBSLVSTS_HST_NTFY_STS)
+ return i801_host_notify_isr(priv);
+ }
+
status = inb_p(SMBHSTSTS(priv));
if (status & SMBHSTSTS_BYTE_DONE)
i801_isr_byte_done(priv);
@@ -540,7 +635,7 @@ static irqreturn_t i801_isr(int irq, void *dev_id)
status &= SMBHSTSTS_INTR | STATUS_ERROR_FLAGS;
if (status) {
outb_p(status, SMBHSTSTS(priv));
- priv->status |= status;
+ priv->status = status;
wake_up(&priv->waitq);
}
@@ -718,6 +813,12 @@ 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 +921,7 @@ 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;
}
@@ -833,7 +935,28 @@ static u32 i801_func(struct i2c_adapter *adapter)
I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
((priv->features & FEATURE_I2C_BLOCK_READ) ?
- I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0);
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0) |
+ ((priv->features & FEATURE_HOST_NOTIFY) ?
+ I2C_FUNC_SMBUS_HOST_NOTIFY : 0);
+}
+
+static int i801_enable_host_notify(struct i2c_adapter *adapter)
+{
+ struct i801_priv *priv = i2c_get_adapdata(adapter);
+
+ if (!(priv->features & FEATURE_HOST_NOTIFY))
+ return -ENOTSUPP;
+
+ if (!priv->host_notify)
+ priv->host_notify = i2c_setup_smbus_host_notify(adapter);
+ if (!priv->host_notify)
+ return -ENOMEM;
+
+ outb_p(SMBSLVCMD_HST_NTFY_INTREN, SMBSLVCMD(priv));
+ /* clear Host Notify bit to allow a new notification */
+ outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
+
+ return 0;
}
static const struct i2c_algorithm smbus_algorithm = {
@@ -1008,8 +1131,7 @@ static void __init input_apanel_init(void) {}
static void i801_probe_optional_slaves(struct i801_priv *priv) {}
#endif /* CONFIG_X86 && CONFIG_DMI */
-#if (defined CONFIG_I2C_MUX_GPIO || defined CONFIG_I2C_MUX_GPIO_MODULE) && \
- defined CONFIG_DMI
+#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
static struct i801_mux_config i801_mux_config_asus_z8_d12 = {
.gpio_chip = "gpio_ich",
.values = { 0x02, 0x03 },
@@ -1257,6 +1379,83 @@ 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 +1473,7 @@ 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) {
@@ -1287,6 +1487,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
priv->features |= FEATURE_SMBUS_PEC;
priv->features |= FEATURE_BLOCK_BUFFER;
priv->features |= FEATURE_TCO;
+ priv->features |= FEATURE_HOST_NOTIFY;
break;
case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0:
@@ -1306,6 +1507,8 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
priv->features |= FEATURE_BLOCK_BUFFER;
/* fall through */
case PCI_DEVICE_ID_INTEL_82801CA_3:
+ priv->features |= FEATURE_HOST_NOTIFY;
+ /* fall through */
case PCI_DEVICE_ID_INTEL_82801BA_2:
case PCI_DEVICE_ID_INTEL_82801AB_3:
case PCI_DEVICE_ID_INTEL_82801AA_3:
@@ -1336,10 +1539,8 @@ 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 +1549,7 @@ 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;
}
@@ -1412,9 +1614,19 @@ 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;
}
+ /*
+ * Enable Host Notify for chips that supports it.
+ * It is done after i2c_add_adapter() so that we are sure the work queue
+ * is not used if i2c_add_adapter() fails.
+ */
+ err = i801_enable_host_notify(&priv->adapter);
+ if (err && err != -ENOTSUPP)
+ dev_warn(&dev->dev, "Unable to enable SMBus Host Notify\n");
+
i801_probe_optional_slaves(priv);
/* We ignore errors - multiplexing is optional */
i801_add_mux(priv);
@@ -1438,6 +1650,7 @@ 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);
@@ -1460,6 +1673,14 @@ static int i801_suspend(struct device *dev)
static int i801_resume(struct device *dev)
{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct i801_priv *priv = pci_get_drvdata(pci_dev);
+ int err;
+
+ err = i801_enable_host_notify(&priv->adapter);
+ if (err && err != -ENOTSUPP)
+ dev_warn(dev, "Unable to enable SMBus Host Notify\n");
+
return 0;
}
#endif