[RFC] Rework of i2c-mpc.c - Freescale i2c driver
Jon Smirl
jonsmirl at gmail.com
Wed Nov 7 06:02:12 EST 2007
Second pass at extending i2c core to accept strings of aliases for the
module. This version eliminate the need for separate name and type
fields when selecting a driver. PowerPC has to have a mapping from
device tree names to the i2c drivers, it makes sense to keep this
mapping inside the i2c driver.
Extend i2c-core to support lists of device tree compatible names when
matching drivers
From: Jon Smirl <jonsmirl at gmail.com>
---
drivers/i2c/busses/i2c-mpc.c | 37 +++++++------------------------------
drivers/i2c/i2c-core.c | 35 ++++++++++++++++++-----------------
drivers/rtc/rtc-pcf8563.c | 1 +
drivers/rtc/rtc-rs5c372.c | 3 ++-
include/linux/i2c.h | 13 +++++++++----
5 files changed, 37 insertions(+), 52 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index 4ddebe4..30420ad 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -312,34 +312,6 @@ static struct i2c_adapter mpc_ops = {
.retries = 1
};
-struct i2c_driver_device {
- char *of_device;
- char *i2c_driver;
- char *i2c_type;
-};
-
-static struct i2c_driver_device i2c_devices[] = {
- {"ricoh,rs5c372a", "rtc-rs5c372", "rs5c372a",},
- {"ricoh,rs5c372b", "rtc-rs5c372", "rs5c372b",},
- {"ricoh,rv5c386", "rtc-rs5c372", "rv5c386",},
- {"ricoh,rv5c387a", "rtc-rs5c372", "rv5c387a",},
- {"epson,pcf8564", "rtc-pcf8563", "pcf8564",},
-};
-
-static int of_find_i2c_driver(struct device_node *node, struct
i2c_board_info *info)
-{
- int i;
-
- for (i = 0; i < ARRAY_SIZE(i2c_devices); i++) {
- if (!of_device_is_compatible(node, i2c_devices[i].of_device))
- continue;
- strncpy(info->driver_name, i2c_devices[i].i2c_driver, KOBJ_NAME_LEN);
- strncpy(info->type, i2c_devices[i].i2c_type, I2C_NAME_SIZE);
- return 0;
- }
- return -ENODEV;
-}
-
static void of_register_i2c_devices(struct i2c_adapter *adap, struct
device_node *adap_node)
{
struct device_node *node = NULL;
@@ -347,11 +319,12 @@ static void of_register_i2c_devices(struct
i2c_adapter *adap, struct device_node
while ((node = of_get_next_child(adap_node, node))) {
struct i2c_board_info info;
const u32 *addr;
+ const char *compatible;
int len;
addr = of_get_property(node, "reg", &len);
if (!addr || len < sizeof(int) || *addr > (1 << 10) - 1) {
- printk(KERN_WARNING "i2c-mpc.c: invalid i2c device entry\n");
+ printk(KERN_WARNING "i2c-mpc.c: invalid entry, missing reg attribute\n");
continue;
}
@@ -359,8 +332,12 @@ static void of_register_i2c_devices(struct
i2c_adapter *adap, struct device_node
if (info.irq == NO_IRQ)
info.irq = -1;
- if (of_find_i2c_driver(node, &info) < 0)
+ compatible = of_get_property(node, "compatible", &len);
+ if (!compatible) {
+ printk(KERN_WARNING "i2c-mpc.c: invalid entry, missing compatible
attribute\n");
continue;
+ }
+ strncpy(info.name, compatible, sizeof(info.name));
info.platform_data = NULL;
info.addr = *addr;
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index d663e69..d9a70c2 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -17,7 +17,7 @@
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* ------------------------------------------------------------------------- */
-/* With some changes from Kyösti Mälkki <kmalkki at cc.hut.fi>.
+/* With some changes from Kyösti MÀlkki <kmalkki at cc.hut.fi>.
All SMBus-related things are written by Frodo Looijaard <frodol at dds.nl>
SMBus 2.0 support by Mark Studebaker <mdsxyz123 at yahoo.com> and
Jean Delvare <khali at linux-fr.org> */
@@ -51,6 +51,7 @@ static int i2c_device_match(struct device *dev,
struct device_driver *drv)
{
struct i2c_client *client = to_i2c_client(dev);
struct i2c_driver *driver = to_i2c_driver(drv);
+ char const **alias;
/* make legacy i2c drivers bypass driver model probing entirely;
* such drivers scan each i2c adapter/bus themselves.
@@ -60,8 +61,18 @@ static int i2c_device_match(struct device *dev,
struct device_driver *drv)
/* new style drivers use the same kind of driver matching policy
* as platform devices or SPI: compare device and driver IDs.
+ * Match against arrary of alias device tree names. When a match
+ * is found change the reference to point at the copy inside the
+ * chip driver allowing the caller's string to be freed.
*/
- return strcmp(client->driver_name, drv->name) == 0;
+ alias = driver->aliases;
+ while (*alias) {
+ if (strcmp(client->name, *alias) == 0) {
+ return true;
+ }
+ alias++;
+ }
+ return 0;
}
#ifdef CONFIG_HOTPLUG
@@ -74,11 +85,11 @@ static int i2c_device_uevent(struct device *dev,
char **envp, int num_envp,
int i = 0, length = 0;
/* by definition, legacy drivers can't hotplug */
- if (dev->driver || !client->driver_name)
+ if (dev->driver || !client->name)
return 0;
if (add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
- "MODALIAS=%s", client->driver_name))
+ "MODALIAS=%s", client->name))
return -ENOMEM;
envp[i] = NULL;
dev_dbg(dev, "uevent\n");
@@ -169,22 +180,15 @@ static void i2c_client_dev_release(struct device *dev)
kfree(to_i2c_client(dev));
}
-static ssize_t show_client_name(struct device *dev, struct
device_attribute *attr, char *buf)
-{
- struct i2c_client *client = to_i2c_client(dev);
- return sprintf(buf, "%s\n", client->name);
-}
-
static ssize_t show_modalias(struct device *dev, struct
device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
- return client->driver_name
- ? sprintf(buf, "%s\n", client->driver_name)
+ return client->name
+ ? sprintf(buf, "%s\n", client->name)
: 0;
}
static struct device_attribute i2c_dev_attrs[] = {
- __ATTR(name, S_IRUGO, show_client_name, NULL),
/* modalias helps coldplug: modprobe $(cat .../modalias) */
__ATTR(modalias, S_IRUGO, show_modalias, NULL),
{ },
@@ -233,10 +237,7 @@ i2c_new_device(struct i2c_adapter *adap, struct
i2c_board_info const *info)
client->flags = info->flags;
client->addr = info->addr;
client->irq = info->irq;
-
- strlcpy(client->driver_name, info->driver_name,
- sizeof(client->driver_name));
- strlcpy(client->name, info->type, sizeof(client->name));
+ strlcpy(client->name, info->name, sizeof(info->name));
/* a new style driver may be bound to this device when we
* return from this function, or any later moment (e.g. maybe
diff --git a/drivers/rtc/rtc-pcf8563.c b/drivers/rtc/rtc-pcf8563.c
index b778d35..8162f77 100644
--- a/drivers/rtc/rtc-pcf8563.c
+++ b/drivers/rtc/rtc-pcf8563.c
@@ -266,6 +266,7 @@ static struct i2c_driver pcf8563_driver = {
.driver = {
.name = "rtc-pcf8563",
},
+ .aliases = (char const *[]){"philips,pcf8563", "epson,rtc8564", 0},
.id = I2C_DRIVERID_PCF8563,
.probe = &pcf8563_probe,
.remove = &pcf8563_remove,
diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c
index 6b67b50..b2da981 100644
--- a/drivers/rtc/rtc-rs5c372.c
+++ b/drivers/rtc/rtc-rs5c372.c
@@ -62,11 +62,11 @@
enum rtc_type {
- rtc_undef = 0,
rtc_rs5c372a,
rtc_rs5c372b,
rtc_rv5c386,
rtc_rv5c387a,
+ rtc_undef,
};
/* REVISIT: this assumes that:
@@ -649,6 +649,7 @@ static struct i2c_driver rs5c372_driver = {
.driver = {
.name = "rtc-rs5c372",
},
+ .aliases = (char const
*[]){"ricoh,rs5c372a","ricoh,rs5c372b","ricoh,rv5c386","ricoh,rv5c387a", 0},
.probe = rs5c372_probe,
.remove = rs5c372_remove,
};
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 2a32f2f..4384cc1 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -107,6 +107,13 @@ extern s32 i2c_smbus_write_i2c_block_data(struct
i2c_client * client,
struct i2c_driver {
int id;
unsigned int class;
+
+ /* Alias names for the driver. Used to support device trees on
+ * the PowerPC architecture. Device tree names take the form of
+ * vendor,chip. For example "epson,rtc8564". Alias is a list of
+ * strings terminated by a zero entry.
+ */
+ char const **aliases;
/* Notifies the driver that a new bus has appeared. This routine
* can be used by the driver to test if the bus meets its conditions
@@ -146,7 +153,7 @@ struct i2c_driver {
};
#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
-#define I2C_NAME_SIZE 20
+#define I2C_NAME_SIZE 40
/**
* struct i2c_client - represent an I2C slave device
@@ -181,7 +188,6 @@ struct i2c_client {
/* to the client */
struct device dev; /* the device structure */
int irq; /* irq issued by device (or -1) */
- char driver_name[KOBJ_NAME_LEN];
struct list_head list;
struct completion released;
};
@@ -225,8 +231,7 @@ static inline void i2c_set_clientdata (struct
i2c_client *dev, void *data)
* with the adapter already known.
*/
struct i2c_board_info {
- char driver_name[KOBJ_NAME_LEN];
- char type[I2C_NAME_SIZE];
+ char name[I2C_NAME_SIZE];
unsigned short flags;
unsigned short addr;
void *platform_data;
--
Jon Smirl
jonsmirl at gmail.com
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