From a7ae81952cdab56a1277bd2f9ed7284c0f575120 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Thu, 9 Jun 2016 16:56:28 +0300 Subject: i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Many Intel systems the BIOS declares a SystemIO OpRegion below the SMBus PCI device as can be seen in ACPI DSDT table from Lenovo Yoga 900: Device (SBUS) { OperationRegion (SMBI, SystemIO, (SBAR << 0x05), 0x10) Field (SMBI, ByteAcc, NoLock, Preserve) { HSTS, 8, Offset (0x02), HCON, 8, HCOM, 8, TXSA, 8, DAT0, 8, DAT1, 8, HBDR, 8, PECR, 8, RXSA, 8, SDAT, 16 } There are also bunch of AML methods that that the BIOS can use to access these fields. Most of the systems in question AML methods accessing the SMBI OpRegion are never used. Now, because of this SMBI OpRegion many systems fail to load the SMBus driver with an error looking like one below: ACPI Warning: SystemIO range 0x0000000000003040-0x000000000000305F conflicts with OpRegion 0x0000000000003040-0x000000000000304F (\_SB.PCI0.SBUS.SMBI) (20160108/utaddress-255) ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver The reason is that this SMBI OpRegion conflicts with the PCI BAR used by the SMBus driver. It turns out that we can install a custom SystemIO address space handler for the SMBus device to intercept all accesses through that OpRegion. This allows us to share the PCI BAR with the AML code if it for some reason is using it. We do not expect that this OpRegion handler will ever be called but if it is we print a warning and prevent all access from the SMBus driver itself. Link: https://bugzilla.kernel.org/show_bug.cgi?id=110041 Reported-by: Andy Lutomirski Reported-by: Pali Rohár Suggested-by: Rafael J. Wysocki Signed-off-by: Mika Westerberg Acked-by: Rafael J. Wysocki Reviewed-by: Jean Delvare Reviewed-by: Benjamin Tissoires Tested-by: Pali Rohár Tested-by: Jean Delvare Signed-off-by: Wolfram Sang Cc: stable@vger.kernel.org --- drivers/i2c/busses/i2c-i801.c | 99 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 96 insertions(+), 3 deletions(-) (limited to 'drivers') 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); -- cgit v1.2.3 From 908cf12bbca0f18a23085a5a35301509e034f0a9 Mon Sep 17 00:00:00 2001 From: Jan Glauber Date: Wed, 8 Jun 2016 08:51:17 +0200 Subject: i2c: octeon: Missing AAK flag in case of I2C_M_RECV_LEN During receive the controller requires the AAK flag for all bytes but the final one. This was wrong in case of I2C_M_RECV_LEN, where the decision if the final byte is to be transmitted happened before adding the additional received length byte. Set the AAK flag if additional bytes are to be received. Signed-off-by: Jan Glauber Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-octeon.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c index aa5f01efd826..1922e4a16e92 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 */ -- cgit v1.2.3 From 8913f8d2930368f30998e60851259606eeed2c49 Mon Sep 17 00:00:00 2001 From: Jan Glauber Date: Wed, 8 Jun 2016 08:51:19 +0200 Subject: i2c: octeon: Avoid printk after too long SMBUS message Remove the warning about a too long SMBUS message because the ipmi_ssif driver triggers this warning too frequently so it spams the message log. Signed-off-by: Jan Glauber Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-octeon.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c index 1922e4a16e92..30ae35146723 100644 --- a/drivers/i2c/busses/i2c-octeon.c +++ b/drivers/i2c/busses/i2c-octeon.c @@ -957,12 +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]; } -- cgit v1.2.3 From 9f05e6219023116b59f6495e8c4d4ba352dd5fea Mon Sep 17 00:00:00 2001 From: Lukasz Gemborowski Date: Mon, 6 Jun 2016 15:51:50 +0200 Subject: i2c: mux: reg: Provide of_match_table of_match_table was not filled which prevents device to be instantiated from device tree node. Signed-off-by: Lukasz Gemborowski Reviewed-by: Alexander Sverdlin Signed-off-by: Wolfram Sang --- drivers/i2c/muxes/i2c-mux-reg.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') 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), }, }; -- cgit v1.2.3