i2c: rcar: add HostNotify support

The I2C core can now utilize a slave interface to handle SMBus
HostNotify events. Enable it in this driver.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 46a24faef35253c3abaee72bf0d3c17822103c62..2077ed8de681b6d62bf131b12fe10f580af26f4f 100644 (file)
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1181,6 +1181,7 @@ config I2C_RCAR
        tristate "Renesas R-Car I2C Controller"
        depends on ARCH_RENESAS || COMPILE_TEST
        select I2C_SLAVE
+       select I2C_SMBUS
        select RESET_CONTROLLER if ARCH_RCAR_GEN3
        help
          If you say yes to this option, support will be included for the

diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index bab90d3f68e6a1e905033d9ffdb9e27eca210034..93b872e415464c18ea53a6a70c93467ee679dc38 100644 (file)
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -21,6 +21,7 @@
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
@@ -106,10 +107,11 @@
 #define ID_ARBLOST     (1 << 3)
 #define ID_NACK                (1 << 4)
 /* persistent flags */
+#define ID_P_HOST_NOTIFY       BIT(28)
 #define ID_P_REP_AFTER_RD      BIT(29)
 #define ID_P_NO_RXDMA          BIT(30) /* HW forbids RXDMA sometimes */
 #define ID_P_PM_BLOCKED                BIT(31)
-#define ID_P_MASK              GENMASK(31, 29)
+#define ID_P_MASK              GENMASK(31, 28)
 
 enum rcar_i2c_type {
        I2C_RCAR_GEN1,
@@ -141,6 +143,8 @@ struct rcar_i2c_priv {
 
        struct reset_control *rstc;
        int irq;
+
+       struct i2c_client *host_notify_client;
 };
 
 #define rcar_i2c_priv_to_dev(p)                ((p)->adap.dev.parent)
@@ -875,14 +879,21 @@ static int rcar_unreg_slave(struct i2c_client *slave)
 
 static u32 rcar_i2c_func(struct i2c_adapter *adap)
 {
+       struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
+
        /*
         * This HW can't do:
         * I2C_SMBUS_QUICK (setting FSB during START didn't work)
         * I2C_M_NOSTART (automatically sends address after START)
         * I2C_M_IGNORE_NAK (automatically sends STOP after NAK)
         */
-       return I2C_FUNC_I2C | I2C_FUNC_SLAVE |
-               (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+       u32 func = I2C_FUNC_I2C | I2C_FUNC_SLAVE |
+                  (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+
+       if (priv->flags & ID_P_HOST_NOTIFY)
+               func |= I2C_FUNC_SMBUS_HOST_NOTIFY;
+
+       return func;
 }
 
 static const struct i2c_algorithm rcar_i2c_algo = {
@@ -982,6 +993,8 @@ static int rcar_i2c_probe(struct platform_device *pdev)
        else
                pm_runtime_put(dev);
 
+       if (of_property_read_bool(dev->of_node, "smbus"))
+               priv->flags |= ID_P_HOST_NOTIFY;
 
        priv->irq = platform_get_irq(pdev, 0);
        ret = devm_request_irq(dev, priv->irq, rcar_i2c_irq, 0, dev_name(dev), priv);
@@ -996,10 +1009,20 @@ static int rcar_i2c_probe(struct platform_device *pdev)
        if (ret < 0)
                goto out_pm_disable;
 
+       if (priv->flags & ID_P_HOST_NOTIFY) {
+               priv->host_notify_client = i2c_new_slave_host_notify_device(adap);
+               if (IS_ERR(priv->host_notify_client)) {
+                       ret = PTR_ERR(priv->host_notify_client);
+                       goto out_del_device;
+               }
+       }
+
        dev_info(dev, "probed\n");
 
        return 0;
 
+ out_del_device:
+       i2c_del_adapter(&priv->adap);
  out_pm_put:
        pm_runtime_put(dev);
  out_pm_disable:
@@ -1012,6 +1035,8 @@ static int rcar_i2c_remove(struct platform_device *pdev)
        struct rcar_i2c_priv *priv = platform_get_drvdata(pdev);
        struct device *dev = &pdev->dev;
 
+       if (priv->host_notify_client)
+               i2c_free_slave_host_notify_device(priv->host_notify_client);
        i2c_del_adapter(&priv->adap);
        rcar_i2c_release_dma(priv);
        if (priv->flags & ID_P_PM_BLOCKED)