The i801 chip can handle the Host Notify feature since ICH 3 as mentioned in http://www.intel.com/content/dam/doc/datasheet/82801ca-io-controller-hub-3-datasheet.pdf Implement .toggle_smbus_host_notify() and rely on .alert() to notify the actual client that it has a notification. With a T440s and a Synaptics touchpad that implements Host Notify, the payload data is always 0x0000, so I am not sure if the device actually sends the payload or if there is a problem regarding the implementation. Part of this code is inspired by i2c-smbus.c. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> --- drivers/i2c/busses/i2c-i801.c | 223 +++++++++++++++++++++++++++++++++--------- drivers/i2c/i2c-core.c | 34 +++++++ drivers/i2c/i2c-smbus.c | 17 +--- include/linux/i2c.h | 3 + 4 files changed, 217 insertions(+), 60 deletions(-) diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 5ecbb3f..22a3218 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -20,46 +20,46 @@ /* * Supports the following Intel I/O Controller Hubs (ICH): * - * I/O Block I2C - * region SMBus Block proc. block - * Chip name PCI ID size PEC buffer call read - * --------------------------------------------------------------------------- - * 82801AA (ICH) 0x2413 16 no no no no - * 82801AB (ICH0) 0x2423 16 no no no no - * 82801BA (ICH2) 0x2443 16 no no no no - * 82801CA (ICH3) 0x2483 32 soft no no no - * 82801DB (ICH4) 0x24c3 32 hard yes no no - * 82801E (ICH5) 0x24d3 32 hard yes yes yes - * 6300ESB 0x25a4 32 hard yes yes yes - * 82801F (ICH6) 0x266a 32 hard yes yes yes - * 6310ESB/6320ESB 0x269b 32 hard yes yes yes - * 82801G (ICH7) 0x27da 32 hard yes yes yes - * 82801H (ICH8) 0x283e 32 hard yes yes yes - * 82801I (ICH9) 0x2930 32 hard yes yes yes - * EP80579 (Tolapai) 0x5032 32 hard yes yes yes - * ICH10 0x3a30 32 hard yes yes yes - * ICH10 0x3a60 32 hard yes yes yes - * 5/3400 Series (PCH) 0x3b30 32 hard yes yes yes - * 6 Series (PCH) 0x1c22 32 hard yes yes yes - * Patsburg (PCH) 0x1d22 32 hard yes yes yes - * Patsburg (PCH) IDF 0x1d70 32 hard yes yes yes - * Patsburg (PCH) IDF 0x1d71 32 hard yes yes yes - * Patsburg (PCH) IDF 0x1d72 32 hard yes yes yes - * DH89xxCC (PCH) 0x2330 32 hard yes yes yes - * Panther Point (PCH) 0x1e22 32 hard yes yes yes - * Lynx Point (PCH) 0x8c22 32 hard yes yes yes - * Lynx Point-LP (PCH) 0x9c22 32 hard yes yes yes - * Avoton (SOC) 0x1f3c 32 hard yes yes yes - * Wellsburg (PCH) 0x8d22 32 hard yes yes yes - * Wellsburg (PCH) MS 0x8d7d 32 hard yes yes yes - * Wellsburg (PCH) MS 0x8d7e 32 hard yes yes yes - * Wellsburg (PCH) MS 0x8d7f 32 hard yes yes yes - * Coleto Creek (PCH) 0x23b0 32 hard yes yes yes - * Wildcat Point (PCH) 0x8ca2 32 hard yes yes yes - * Wildcat Point-LP (PCH) 0x9ca2 32 hard yes yes yes - * BayTrail (SOC) 0x0f12 32 hard yes yes yes - * Sunrise Point-H (PCH) 0xa123 32 hard yes yes yes - * Sunrise Point-LP (PCH) 0x9d23 32 hard yes yes yes + * I/O SMBus Block I2C + * region Slave Host SMBus Block proc. block + * Chip name PCI ID size mode notify PEC buffer call read + * ------------------------------------------------------------------------------------------ + * 82801AA (ICH) 0x2413 16 no no no no no no + * 82801AB (ICH0) 0x2423 16 no no no no no no + * 82801BA (ICH2) 0x2443 16 yes no no no no no + * 82801CA (ICH3) 0x2483 32 yes yes soft no no no + * 82801DB (ICH4) 0x24c3 32 yes yes hard yes no no + * 82801E (ICH5) 0x24d3 32 yes yes hard yes yes yes + * 6300ESB 0x25a4 32 yes yes hard yes yes yes + * 82801F (ICH6) 0x266a 32 yes yes hard yes yes yes + * 6310ESB/6320ESB 0x269b 32 yes yes hard yes yes yes + * 82801G (ICH7) 0x27da 32 yes yes hard yes yes yes + * 82801H (ICH8) 0x283e 32 yes yes hard yes yes yes + * 82801I (ICH9) 0x2930 32 yes yes hard yes yes yes + * EP80579 (Tolapai) 0x5032 32 yes yes hard yes yes yes + * ICH10 0x3a30 32 yes yes hard yes yes yes + * ICH10 0x3a60 32 yes yes hard yes yes yes + * 5/3400 Series (PCH) 0x3b30 32 yes yes hard yes yes yes + * 6 Series (PCH) 0x1c22 32 yes yes hard yes yes yes + * Patsburg (PCH) 0x1d22 32 yes yes hard yes yes yes + * Patsburg (PCH) IDF 0x1d70 32 yes yes hard yes yes yes + * Patsburg (PCH) IDF 0x1d71 32 yes yes hard yes yes yes + * Patsburg (PCH) IDF 0x1d72 32 yes yes hard yes yes yes + * DH89xxCC (PCH) 0x2330 32 yes yes hard yes yes yes + * Panther Point (PCH) 0x1e22 32 yes yes hard yes yes yes + * Lynx Point (PCH) 0x8c22 32 yes yes hard yes yes yes + * Lynx Point-LP (PCH) 0x9c22 32 yes yes hard yes yes yes + * Avoton (SOC) 0x1f3c 32 yes yes hard yes yes yes + * Wellsburg (PCH) 0x8d22 32 yes yes hard yes yes yes + * Wellsburg (PCH) MS 0x8d7d 32 yes yes hard yes yes yes + * Wellsburg (PCH) MS 0x8d7e 32 yes yes hard yes yes yes + * Wellsburg (PCH) MS 0x8d7f 32 yes yes hard yes yes yes + * Coleto Creek (PCH) 0x23b0 32 yes yes hard yes yes yes + * Wildcat Point (PCH) 0x8ca2 32 yes yes hard yes yes yes + * Wildcat Point-LP (PCH) 0x9ca2 32 yes yes hard yes yes yes + * BayTrail (SOC) 0x0f12 32 yes yes hard yes yes yes + * Sunrise Point-H (PCH) 0xa123 32 yes yes hard yes yes yes + * Sunrise Point-LP (PCH) 0x9d23 32 yes yes hard yes yes yes * * Features supported by this driver: * Software PEC no @@ -68,6 +68,7 @@ * 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. @@ -84,6 +85,7 @@ #include <linux/i2c.h> #include <linux/acpi.h> #include <linux/io.h> +#include <linux/kfifo.h> #include <linux/dmi.h> #include <linux/slab.h> #include <linux/wait.h> @@ -107,6 +109,10 @@ #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 @@ -158,6 +164,12 @@ #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) @@ -221,6 +233,17 @@ struct i801_priv { const struct i801_mux_config *mux_drvdata; struct platform_device *mux_pdev; #endif + + bool host_notify_requested; + struct work_struct host_notify; + struct kfifo host_notify_fifo; +}; + +#define SMBHSTNTFY_SIZE 8 + +struct smbus_host_notify_data { + u8 addr; + u16 payload; }; #define FEATURE_SMBUS_PEC (1 << 0) @@ -228,6 +251,7 @@ struct i801_priv { #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) @@ -237,6 +261,7 @@ static const char *i801_feature_names[] = { "Block process call", "I2C block read", "Interrupt", + "SMBus Host Notify", }; static unsigned int disable_features; @@ -245,7 +270,8 @@ 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. */ @@ -479,8 +505,67 @@ static void i801_isr_byte_done(struct i801_priv *priv) outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv)); } +/* If this is the alerting device, notify its driver */ +static int i801_do_host_notify(struct device *dev, void *datap) +{ + struct i2c_client *client = i2c_verify_client(dev); + struct smbus_host_notify_data *data = datap; + + if (!client || client->addr != data->addr) + return 0; + if (client->flags & I2C_CLIENT_TEN) + return 0; + + if (i2c_alert(client, data->payload)) + return 0; + + /* Stop iterating after we find the device */ + return -EBUSY; +} + /* - * There are two kinds of interrupts: + * The alert IRQ handler needs to hand work off to a task which can issue + * SMBus calls, because those sleeping calls can't be made in IRQ context. + */ +static void i801_host_notify(struct work_struct *work) +{ + struct i801_priv *priv; + struct smbus_host_notify_data data; + int count; + + priv = container_of(work, struct i801_priv, host_notify); + + count = kfifo_out(&priv->host_notify_fifo, &data, + sizeof(struct smbus_host_notify_data)); + + if (count != sizeof(struct smbus_host_notify_data)) { + dev_err(&priv->pci_dev->dev, + "Host Notification triggered without data\n"); + return; + } + + device_for_each_child(&priv->adapter.dev, &data, i801_do_host_notify); +} + +static irqreturn_t i801_host_notify_isr(struct i801_priv *priv) +{ + struct smbus_host_notify_data data; + + data.addr = inb_p(SMBNTFDADD(priv)) >> 1; + data.payload = inb_p(SMBNTFDDAT(priv)) | + (inb_p(SMBNTFDDAT(priv) + 1) << 8); + + kfifo_in(&priv->host_notify_fifo, &data, + sizeof(struct smbus_host_notify_data)); + schedule_work(&priv->host_notify); + + /* clear Host Notify bit and return */ + outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv)); + return IRQ_HANDLED; +} + +/* + * There are three kinds of interrupts: * * 1) i801 signals transaction completion with one of these interrupts: * INTR - Success @@ -492,6 +577,8 @@ 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) { @@ -504,6 +591,12 @@ static irqreturn_t i801_isr(int irq, void *dev_id) if (!(pcists & SMBPCISTS_INTS)) return IRQ_NONE; + if (priv->host_notify_requested) { + 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); @@ -801,12 +894,35 @@ 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_toggle_host_ntfy(struct i2c_adapter *adapter, bool state) +{ + struct i801_priv *priv = i2c_get_adapdata(adapter); + + if (!(priv->features & FEATURE_HOST_NOTIFY)) + return -EOPNOTSUPP; + + if (state) { + 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)); + } else { + outb_p(0, SMBSLVCMD(priv)); + } + + priv->host_notify_requested = state; + + return 0; } static const struct i2c_algorithm smbus_algorithm = { - .smbus_xfer = i801_access, - .functionality = i801_func, + .smbus_xfer = i801_access, + .functionality = i801_func, + .toggle_smbus_host_notify = i801_toggle_host_ntfy, }; static const struct pci_device_id i801_ids[] = { @@ -1166,6 +1282,7 @@ 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; case PCI_DEVICE_ID_INTEL_82801BA_2: case PCI_DEVICE_ID_INTEL_82801AB_3: case PCI_DEVICE_ID_INTEL_82801AA_3: @@ -1250,6 +1367,15 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id) } } + INIT_WORK(&priv->host_notify, i801_host_notify); + if (kfifo_alloc(&priv->host_notify_fifo, + SMBHSTNTFY_SIZE * sizeof(struct smbus_host_notify_data), + GFP_KERNEL)) { + dev_err(&dev->dev, + "%s:failed allocating host_notify_fifo\n", __func__); + return -ENOMEM; + } + if (priv->features & FEATURE_IRQ) { init_waitqueue_head(&priv->waitq); @@ -1292,6 +1418,9 @@ static void i801_remove(struct pci_dev *dev) { struct i801_priv *priv = pci_get_drvdata(dev); + cancel_work_sync(&priv->host_notify); + kfifo_free(&priv->host_notify_fifo); + i801_del_mux(priv); i2c_del_adapter(&priv->adapter); pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg); @@ -1315,8 +1444,12 @@ static int i801_suspend(struct pci_dev *dev, pm_message_t mesg) static int i801_resume(struct pci_dev *dev) { + struct i801_priv *priv = pci_get_drvdata(dev); + pci_set_power_state(dev, PCI_D0); pci_restore_state(dev); + if (priv->host_notify_requested) + i801_toggle_host_ntfy(&priv->adapter, true); return 0; } #else diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index eaaf5b0..87904ec 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -2145,6 +2145,40 @@ int i2c_master_send(const struct i2c_client *client, const char *buf, int count) EXPORT_SYMBOL(i2c_master_send); /** + * i2c_alert - call an alert for the given i2c_client. + * @client: Handle to slave device + * @data: Payload data that will be sent to the slave + * + * Returns negative errno, or 0. + */ +int i2c_alert(struct i2c_client *client, unsigned int data) +{ + struct i2c_driver *driver; + + if (!client) + return -EINVAL; + + /* + * Drivers should either disable alerts, or provide at least + * a minimal handler. Lock so the driver won't change. + */ + device_lock(&client->adapter->dev); + if (client->dev.driver) { + driver = to_i2c_driver(client->dev.driver); + if (driver->alert) + driver->alert(client, data); + else + dev_warn(&client->dev, "no driver alert()!\n"); + } else + dev_dbg(&client->dev, "alert with no driver\n"); + device_unlock(&client->adapter->dev); + + return 0; +} +EXPORT_SYMBOL_GPL(i2c_alert); + + +/** * i2c_master_recv - issue a single I2C message in master receive mode * @client: Handle to slave device * @buf: Where to store data read from slave diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c index 9ebf9cb..26439a8 100644 --- a/drivers/i2c/i2c-smbus.c +++ b/drivers/i2c/i2c-smbus.c @@ -41,27 +41,14 @@ static int smbus_do_alert(struct device *dev, void *addrp) { struct i2c_client *client = i2c_verify_client(dev); struct alert_data *data = addrp; - struct i2c_driver *driver; if (!client || client->addr != data->addr) return 0; if (client->flags & I2C_CLIENT_TEN) return 0; - /* - * Drivers should either disable alerts, or provide at least - * a minimal handler. Lock so the driver won't change. - */ - device_lock(dev); - if (client->dev.driver) { - driver = to_i2c_driver(client->dev.driver); - if (driver->alert) - driver->alert(client, data->flag); - else - dev_warn(&client->dev, "no driver alert()!\n"); - } else - dev_dbg(&client->dev, "alert with no driver\n"); - device_unlock(dev); + if (i2c_alert(client, data->flag)) + return 0; /* Stop iterating after we find the device */ return -EBUSY; diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 7ffc970..fbca48a 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -72,6 +72,9 @@ extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, extern int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); +/* call an alert. */ +extern int i2c_alert(struct i2c_client *client, unsigned int data); + /* This is the very generalized SMBus access routine. You probably do not want to use this, though; one of the functions below may be much easier, and probably just as fast. -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
