i2c: Move bus management and OPAL API to core i2c code

And start adding interfaces to lookup i2c busses.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

5 files changed, 152 insertions, 122 deletions

diff --git a/core/Makefile.inc b/core/Makefile.inc
index 5098d2d..475e2c7 100644
--- a/core/Makefile.inc
+++ b/core/Makefile.inc
@@ -7,7 +7,7 @@ CORE_OBJS += timebase.o opal-msg.o pci.o pci-opal.o fast-reboot.o
 CORE_OBJS += device.o exceptions.o trace.o affinity.o vpd.o
 CORE_OBJS += hostservices.o platform.o nvram.o flash-nvram.o hmi.o
 CORE_OBJS += console-log.o ipmi.o time-utils.o pel.o pool.o errorlog.o
-CORE_OBJS += timer.o
+CORE_OBJS += timer.o i2c.o
 CORE=core/built-in.o
 
 $(CORE): $(CORE_OBJS:%=core/%)
diff --git a/core/i2c.c b/core/i2c.c
new file mode 100644
index 0000000..2eb77db
--- /dev/null
+++ b/core/i2c.c
@@ -0,0 +1,116 @@
+/* Copyright 2013-2014 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <skiboot.h>
+#include <i2c.h>
+#include <opal.h>
+#include <device.h>
+#include <opal-msg.h>
+
+LIST_HEAD(i2c_bus_list);
+
+/* Used to assign OPAL IDs */
+static uint32_t i2c_next_bus;
+
+void i2c_add_bus(struct i2c_bus *bus)
+{
+	bus->opal_id = ++i2c_next_bus;
+	dt_add_property_cells(bus->dt_node, "ibm,opal-id", bus->opal_id);
+
+	list_add_tail(&i2c_bus_list, &bus->link);
+}
+
+struct i2c_bus *i2c_find_bus_by_id(uint32_t opal_id)
+{
+	struct i2c_bus *bus;
+
+	list_for_each(&i2c_bus_list, bus, link) {
+		if (bus->opal_id == opal_id)
+			return bus;
+	}
+	return NULL;
+}
+
+static void opal_i2c_request_complete(int rc, struct i2c_request *req)
+{
+	uint64_t token = (uint64_t)(unsigned long)req->user_data;
+
+	opal_queue_msg(OPAL_MSG_ASYNC_COMP, NULL, NULL, token, rc);
+	i2c_free_req(req);
+}
+
+static int opal_i2c_request(uint64_t async_token, uint32_t bus_id,
+			    struct opal_i2c_request *oreq)
+{
+	struct i2c_bus *bus = NULL;
+	struct i2c_request *req;
+	int rc;
+
+	if (oreq->flags & OPAL_I2C_ADDR_10)
+		return OPAL_UNSUPPORTED;
+
+	bus = i2c_find_bus_by_id(bus_id);
+	if (!bus) {
+		prlog(PR_ERR, "I2C: Invalid 'bus_id' passed to the OPAL\n");
+		return OPAL_PARAMETER;
+	}
+
+	req = i2c_alloc_req(bus);
+	if (!req) {
+		prlog(PR_ERR, "I2C: Failed to allocate 'i2c_request'\n");
+		return OPAL_NO_MEM;
+	}
+
+	switch(oreq->type) {
+	case OPAL_I2C_RAW_READ:
+		req->op = I2C_READ;
+		break;
+	case OPAL_I2C_RAW_WRITE:
+		req->op = I2C_WRITE;
+		break;
+	case OPAL_I2C_SM_READ:
+		req->op = SMBUS_READ;
+		req->offset = oreq->subaddr;
+		req->offset_bytes = oreq->subaddr_sz;
+		break;
+	case OPAL_I2C_SM_WRITE:
+		req->op = SMBUS_WRITE;
+		req->offset = oreq->subaddr;
+		req->offset_bytes = oreq->subaddr_sz;
+		break;
+	default:
+		bus->free_req(req);
+		return OPAL_PARAMETER;
+	}
+	req->dev_addr = oreq->addr;
+	req->rw_len = oreq->size;
+	req->rw_buf = (void *)oreq->buffer_ra;
+	req->completion = opal_i2c_request_complete;
+	req->user_data = (void *)(unsigned long)async_token;
+	req->bus = bus;
+
+	/* Finally, queue the OPAL i2c request and return */
+	rc = i2c_queue_req(req);
+	if (rc) {
+		i2c_free_req(req);
+		return rc;
+	}
+
+	return OPAL_ASYNC_COMPLETION;
+}
+opal_call(OPAL_I2C_REQUEST, opal_i2c_request, 3);
+
+
diff --git a/hw/p8-i2c.c b/hw/p8-i2c.c
index ef17c40..e3f35b1 100644
--- a/hw/p8-i2c.c
+++ b/hw/p8-i2c.c
@@ -16,7 +16,6 @@
 
 #undef DEBUG
 
-#include <fsp.h>
 #include <opal.h>
 #include <lock.h>
 #include <chip.h>
@@ -24,7 +23,6 @@
 #include <xscom.h>
 #include <timebase.h>
 #include <timer.h>
-#include <opal-msg.h>
 
 #ifdef DEBUG
 #define DBG(fmt...) prlog(PR_ERR, "I2C: " fmt)
@@ -192,7 +190,6 @@ struct p8_i2c_master {
 struct p8_i2c_master_port {
 	struct i2c_bus		bus; /* Abstract bus struct for the client */
 	struct p8_i2c_master	*common;
-	uint32_t		bus_id;
 	uint32_t		port_num;
 };
 
@@ -202,8 +199,6 @@ struct p8_i2c_request {
 	uint64_t		timeout;
 };
 
-static LIST_HEAD(i2c_bus_list);
-
 static bool p8_i2c_has_irqs(void)
 {
 	struct proc_chip *chip = next_chip(NULL);
@@ -830,8 +825,9 @@ static void p8_i2c_check_work(struct p8_i2c_master *master)
 	}
 }
 
-static int p8_i2c_queue_request(struct i2c_bus *bus, struct i2c_request *req)
+static int p8_i2c_queue_request(struct i2c_request *req)
 {
+	struct i2c_bus *bus = req->bus;
 	struct p8_i2c_master_port *port =
 		container_of(bus, struct p8_i2c_master_port, bus);
 	struct p8_i2c_master *master = port->common;
@@ -1014,85 +1010,11 @@ void p8_i2c_interrupt(void)
 	p8_i2c_poll_each_master(true);
 }
 
-static void opal_p8_i2c_request_complete(int rc, struct i2c_request *req)
-{
-	uint64_t token = (uint64_t)(unsigned long)req->user_data;
-
-	opal_queue_msg(OPAL_MSG_ASYNC_COMP, NULL, NULL, token, rc);
-	req->bus->free_req(req);
-}
-
-static int opal_p8_i2c_request(uint64_t async_token, uint32_t bus_id,
-			       struct opal_i2c_request *oreq)
-{
-	struct p8_i2c_master_port *port;
-	struct i2c_bus *bus = NULL;
-	struct i2c_request *req;
-	int rc;
-
-	if (oreq->flags & OPAL_I2C_ADDR_10)
-		return OPAL_UNSUPPORTED;
-
-	list_for_each(&i2c_bus_list, bus, link) {
-		port = container_of(bus, struct p8_i2c_master_port, bus);
-		if (port->bus_id == bus_id)
-			break;
-	}
-	if (!bus) {
-		prlog(PR_ERR, "I2C: Invalid 'bus_id' passed to the OPAL\n");
-		return OPAL_PARAMETER;
-	}
-
-	req = bus->alloc_req(bus);
-	if (!req) {
-		prlog(PR_ERR, "I2C: Failed to allocate 'i2c_request'\n");
-		return OPAL_NO_MEM;
-	}
-
-	switch(oreq->type) {
-	case OPAL_I2C_RAW_READ:
-		req->op = I2C_READ;
-		break;
-	case OPAL_I2C_RAW_WRITE:
-		req->op = I2C_WRITE;
-		break;
-	case OPAL_I2C_SM_READ:
-		req->op = SMBUS_READ;
-		req->offset = oreq->subaddr;
-		req->offset_bytes = oreq->subaddr_sz;
-		break;
-	case OPAL_I2C_SM_WRITE:
-		req->op = SMBUS_WRITE;
-		req->offset = oreq->subaddr;
-		req->offset_bytes = oreq->subaddr_sz;
-		break;
-	default:
-		bus->free_req(req);
-		return OPAL_PARAMETER;
-	}
-	req->dev_addr = oreq->addr;
-	req->rw_len = oreq->size;
-	req->rw_buf = (void *)oreq->buffer_ra;
-	req->completion = opal_p8_i2c_request_complete;
-	req->user_data = (void *)(unsigned long)async_token;
-	req->bus = bus;
-
-	/* Finally, queue the OPAL i2c request and return */
-	rc = bus->queue_req(bus, req);
-	if (rc) {
-		bus->free_req(req);
-		return rc;
-	}
-
-	return OPAL_ASYNC_COMPLETION;
-}
-
 void p8_i2c_init(void)
 {
-	struct p8_i2c_master_port *port, *prev_port;
+	struct p8_i2c_master_port *port;
 	uint32_t bus_speed, lb_freq, count;
 	struct dt_node *i2cm, *i2cm_port;
-	struct i2c_bus *bus, *next_bus;
 	struct p8_i2c_master *master;
 	uint64_t ex_stat;
 	static bool irq_printed;
@@ -1102,7 +1024,7 @@ void p8_i2c_init(void)
 		master = zalloc(sizeof(*master));
 		if (!master) {
 			prlog(PR_ERR,"I2C: Failed to allocate p8_i2c_master\n");
-			goto exit_free_list;
+			break;
 		}
 
 		/* Bus speed in KHz */
@@ -1119,7 +1041,8 @@ void p8_i2c_init(void)
 				I2C_EXTD_STAT_REG, &ex_stat);
 		if (rc) {
 			prlog(PR_ERR, "I2C: Failed to read EXTD_STAT_REG\n");
-			goto exit_free_master;
+			free(master);
+			break;
 		}
 
 		master->fifo_size = GETFIELD(I2C_EXTD_STAT_FIFO_SIZE, ex_stat);
@@ -1145,19 +1068,18 @@ void p8_i2c_init(void)
 		port = zalloc(sizeof(*port) * count);
 		if (!port) {
 			prlog(PR_ERR, "I2C: Insufficient memory\n");
-			goto exit_free_master;
+			free(master);
+			break;
 		}
 
 		dt_for_each_child(i2cm, i2cm_port) {
-			port->bus_id = dt_prop_get_u32(i2cm_port,
-						       "ibm,opal-id");
 			port->port_num = dt_prop_get_u32(i2cm_port, "reg");
 			port->common = master;
-			port->bus.i2c_port = i2cm_port;
+			port->bus.dt_node = i2cm_port;
 			port->bus.queue_req = p8_i2c_queue_request;
 			port->bus.alloc_req = p8_i2c_alloc_request;
 			port->bus.free_req = p8_i2c_free_request;
-			list_add_tail(&i2c_bus_list, &port->bus.link);
+			i2c_add_bus(&port->bus);
 			port++;
 		}
 	}
@@ -1167,32 +1089,4 @@ void p8_i2c_init(void)
 	 * and thus no interrupts
 	 */
 	opal_add_poller(p8_i2c_opal_poll, NULL);
-
-	/* Register the OPAL interface */
-	opal_register(OPAL_I2C_REQUEST, opal_p8_i2c_request, 3);
-
-	return;
-
-exit_free_master:
-	free(master);
-exit_free_list:
-	prev_port = NULL;
-	list_for_each_safe(&i2c_bus_list, bus, next_bus, link) {
-		port = container_of(bus, struct p8_i2c_master_port, bus);
-		if (!prev_port) {
-			prev_port = port;
-			continue;
-		} else if (prev_port->common == port->common) {
-			continue;
-		} else {
-			free(prev_port->common);
-			free(prev_port);
-			prev_port = NULL;
-		}
-	}
-
-	if (prev_port) { /* Last node left */
-		free(prev_port->common);
-		free(prev_port);
-	}
 }
diff --git a/include/i2c.h b/include/i2c.h
index af88ba0..2647bdc 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -21,9 +21,9 @@ struct i2c_request;
 
 struct i2c_bus {
 	struct list_node	link;
-	struct dt_node		*i2c_port;
-	int			(*queue_req)(struct i2c_bus *bus,
-					     struct i2c_request *req);
+	struct dt_node		*dt_node;
+	uint32_t		opal_id;
+	int			(*queue_req)(struct i2c_request *req);
 	struct i2c_request	*(*alloc_req)(struct i2c_bus *bus);
 	void			(*free_req)(struct i2c_request *req);
 };
@@ -47,6 +47,28 @@ struct i2c_request {
 	void			*user_data;	/* Client data */
 };
 
+extern struct list_head i2c_bus_list;
+
+/* Generic i2c */
+extern void i2c_add_bus(struct i2c_bus *bus);
+extern struct i2c_bus *i2c_find_bus_by_id(uint32_t opal_id);
+
+static inline struct i2c_request *i2c_alloc_req(struct i2c_bus *bus)
+{
+	return bus->alloc_req(bus);
+}
+
+static inline void i2c_free_req(struct i2c_request *req)
+{
+	req->bus->free_req(req);
+}
+
+static inline int i2c_queue_req(struct i2c_request *req)
+{
+	return req->bus->queue_req(req);
+}
+
+/* P8 implementation details */
 extern void p8_i2c_init(void);
 extern void p8_i2c_interrupt(void);
 
diff --git a/platforms/astbmc/common.c b/platforms/astbmc/common.c
index f79a5c5..e2d8629 100644
--- a/platforms/astbmc/common.c
+++ b/platforms/astbmc/common.c
@@ -174,7 +174,6 @@ static struct dt_node *dt_create_i2c_bus(struct dt_node *i2cm, const char *port_
 					 uint32_t port_id)
 {
 	static struct dt_node *port;
-	static uint32_t bus_id = 0;
 
 	port = dt_new_addr(i2cm, "i2c-bus", port_id);
 	if (!port)
@@ -183,7 +182,6 @@ static struct dt_node *dt_create_i2c_bus(struct dt_node *i2cm, const char *port_
 	dt_add_property_string(port, "compatible", "ibm,power8-i2c-port");
 	dt_add_property_string(port, "port-name", port_name);
 	dt_add_property_cells(port, "reg", port_id);
-	dt_add_property_cells(port, "ibm,opal-id", ++bus_id);
 	dt_add_property_cells(port, "#address-cells", 1);
 	dt_add_property_cells(port, "#size-cells", 0);