i2c: fsi: Add port structures

Add and initialize I2C adapters for each port on the FSI-attached I2C
master. Ports for each master are defined in the devicetree.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c
index 3725db1..1d9e9bf 100644 (file)
--- a/drivers/i2c/busses/i2c-fsi.c
+++ b/drivers/i2c/busses/i2c-fsi.c
@@ -17,7 +17,10 @@
 #include <linux/fsi.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
+#include <linux/list.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>
 
 #define FSI_ENGID_I2C          0x7
 
@@ -128,6 +131,14 @@
 struct fsi_i2c_master {
        struct fsi_device       *fsi;
        u8                      fifo_size;
+       struct list_head        ports;
+};
+
+struct fsi_i2c_port {
+       struct list_head        list;
+       struct i2c_adapter      adapter;
+       struct fsi_i2c_master   *master;
+       u16                     port;
 };
 
 static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg,
@@ -181,9 +192,38 @@ static int fsi_i2c_dev_init(struct fsi_i2c_master *i2c)
        return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_WATER_MARK, &watermark);
 }
 
+static int fsi_i2c_set_port(struct fsi_i2c_port *port)
+{
+       int rc;
+       struct fsi_device *fsi = port->master->fsi;
+       u32 mode, dummy = 0;
+
+       rc = fsi_i2c_read_reg(fsi, I2C_FSI_MODE, &mode);
+       if (rc)
+               return rc;
+
+       if (FIELD_GET(I2C_MODE_PORT, mode) == port->port)
+               return 0;
+
+       mode = (mode & ~I2C_MODE_PORT) | FIELD_PREP(I2C_MODE_PORT, port->port);
+       rc = fsi_i2c_write_reg(fsi, I2C_FSI_MODE, &mode);
+       if (rc)
+               return rc;
+
+       /* reset engine when port is changed */
+       return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy);
+}
+
 static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
                        int num)
 {
+       int rc;
+       struct fsi_i2c_port *port = adap->algo_data;
+
+       rc = fsi_i2c_set_port(port);
+       if (rc)
+               return rc;
+
        return -EOPNOTSUPP;
 }
 
@@ -201,23 +241,73 @@ static const struct i2c_algorithm fsi_i2c_algorithm = {
 static int fsi_i2c_probe(struct device *dev)
 {
        struct fsi_i2c_master *i2c;
+       struct fsi_i2c_port *port;
+       struct device_node *np;
        int rc;
+       u32 port_no;
 
        i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
        if (!i2c)
                return -ENOMEM;
 
        i2c->fsi = to_fsi_dev(dev);
+       INIT_LIST_HEAD(&i2c->ports);
 
        rc = fsi_i2c_dev_init(i2c);
        if (rc)
                return rc;
 
+       /* Add adapter for each i2c port of the master. */
+       for_each_available_child_of_node(dev->of_node, np) {
+               rc = of_property_read_u32(np, "reg", &port_no);
+               if (rc || port_no > USHRT_MAX)
+                       continue;
+
+               port = kzalloc(sizeof(*port), GFP_KERNEL);
+               if (!port)
+                       break;
+
+               port->master = i2c;
+               port->port = port_no;
+
+               port->adapter.owner = THIS_MODULE;
+               port->adapter.dev.of_node = np;
+               port->adapter.dev.parent = dev;
+               port->adapter.algo = &fsi_i2c_algorithm;
+               port->adapter.algo_data = port;
+
+               snprintf(port->adapter.name, sizeof(port->adapter.name),
+                        "i2c_bus-%u", port_no);
+
+               rc = i2c_add_adapter(&port->adapter);
+               if (rc < 0) {
+                       dev_err(dev, "Failed to register adapter: %d\n", rc);
+                       kfree(port);
+                       continue;
+               }
+
+               list_add(&port->list, &i2c->ports);
+       }
+
        dev_set_drvdata(dev, i2c);
 
        return 0;
 }
 
+static int fsi_i2c_remove(struct device *dev)
+{
+       struct fsi_i2c_master *i2c = dev_get_drvdata(dev);
+       struct fsi_i2c_port *port, *tmp;
+
+       list_for_each_entry_safe(port, tmp, &i2c->ports, list) {
+               list_del(&port->list);
+               i2c_del_adapter(&port->adapter);
+               kfree(port);
+       }
+
+       return 0;
+}
+
 static const struct fsi_device_id fsi_i2c_ids[] = {
        { FSI_ENGID_I2C, FSI_VERSION_ANY },
        { }
@@ -229,6 +319,7 @@ static struct fsi_driver fsi_i2c_driver = {
                .name = "i2c-fsi",
                .bus = &fsi_bus_type,
                .probe = fsi_i2c_probe,
+               .remove = fsi_i2c_remove,
        },
 };