diff options
| -rw-r--r-- | drivers/of/base.c | 88 | ||||
| -rw-r--r-- | drivers/of/of_i2c.c | 64 | ||||
| -rw-r--r-- | include/linux/of.h | 1 |
3 files changed, 92 insertions, 61 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 23ffb7c0caf2..ad8ac1a8af28 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -385,3 +385,91 @@ struct device_node *of_find_matching_node(struct device_node *from, return np; } EXPORT_SYMBOL(of_find_matching_node); + +/** + * of_modalias_table: Table of explicit compatible ==> modalias mappings + * + * This table allows particulare compatible property values to be mapped + * to modalias strings. This is useful for busses which do not directly + * understand the OF device tree but are populated based on data contained + * within the device tree. SPI and I2C are the two current users of this + * table. + * + * In most cases, devices do not need to be listed in this table because + * the modalias value can be derived directly from the compatible table. + * However, if for any reason a value cannot be derived, then this table + * provides a method to override the implicit derivation. + * + * At the moment, a single table is used for all bus types because it is + * assumed that the data size is small and that the compatible values + * should already be distinct enough to differentiate between SPI, I2C + * and other devices. + */ +struct of_modalias_table { + char *of_device; + char *modalias; +}; +static struct of_modalias_table of_modalias_table[] = { + /* Empty for now; add entries as needed */ +}; + +/** + * of_modalias_node - Lookup appropriate modalias for a device node + * @node: pointer to a device tree node + * @modalias: Pointer to buffer that modalias value will be copied into + * @len: Length of modalias value + * + * Based on the value of the compatible property, this routine will determine + * an appropriate modalias value for a particular device tree node. Three + * separate methods are used to derive a modalias value. + * + * First method is to lookup the compatible value in of_modalias_table. + * Second is to look for a "linux,<modalias>" entry in the compatible list + * and used that for modalias. Third is to strip off the manufacturer + * prefix from the first compatible entry and use the remainder as modalias + * + * This routine returns 0 on success + */ +int of_modalias_node(struct device_node *node, char *modalias, int len) +{ + int i, cplen; + const char *compatible; + const char *p; + + /* 1. search for exception list entry */ + for (i = 0; i < ARRAY_SIZE(of_modalias_table); i++) { + compatible = of_modalias_table[i].of_device; + if (!of_device_is_compatible(node, compatible)) + continue; + strlcpy(modalias, of_modalias_table[i].modalias, len); + return 0; + } + + compatible = of_get_property(node, "compatible", &cplen); + if (!compatible) + return -ENODEV; + + /* 2. search for linux,<modalias> entry */ + p = compatible; + while (cplen > 0) { + if (!strncmp(p, "linux,", 6)) { + p += 6; + strlcpy(modalias, p, len); + return 0; + } + + i = strlen(p) + 1; + p += i; + cplen -= i; + } + + /* 3. take first compatible entry and strip manufacturer */ + p = strchr(compatible, ','); + if (!p) + return -ENODEV; + p++; + strlcpy(modalias, p, len); + return 0; +} +EXPORT_SYMBOL_GPL(of_modalias_node); + diff --git a/drivers/of/of_i2c.c b/drivers/of/of_i2c.c index 344e1b03dd8b..6a98dc8aa30b 100644 --- a/drivers/of/of_i2c.c +++ b/drivers/of/of_i2c.c @@ -16,62 +16,6 @@ #include <linux/of_i2c.h> #include <linux/module.h> -struct i2c_driver_device { - char *of_device; - char *i2c_type; -}; - -static struct i2c_driver_device i2c_devices[] = { -}; - -static int of_find_i2c_driver(struct device_node *node, - struct i2c_board_info *info) -{ - int i, cplen; - const char *compatible; - const char *p; - - /* 1. search for exception list entry */ - for (i = 0; i < ARRAY_SIZE(i2c_devices); i++) { - if (!of_device_is_compatible(node, i2c_devices[i].of_device)) - continue; - if (strlcpy(info->type, i2c_devices[i].i2c_type, - I2C_NAME_SIZE) >= I2C_NAME_SIZE) - return -ENOMEM; - - return 0; - } - - compatible = of_get_property(node, "compatible", &cplen); - if (!compatible) - return -ENODEV; - - /* 2. search for linux,<i2c-type> entry */ - p = compatible; - while (cplen > 0) { - if (!strncmp(p, "linux,", 6)) { - p += 6; - if (strlcpy(info->type, p, - I2C_NAME_SIZE) >= I2C_NAME_SIZE) - return -ENOMEM; - return 0; - } - - i = strlen(p) + 1; - p += i; - cplen -= i; - } - - /* 3. take fist compatible entry and strip manufacturer */ - p = strchr(compatible, ','); - if (!p) - return -ENODEV; - p++; - if (strlcpy(info->type, p, I2C_NAME_SIZE) >= I2C_NAME_SIZE) - return -ENOMEM; - return 0; -} - void of_register_i2c_devices(struct i2c_adapter *adap, struct device_node *adap_node) { @@ -83,6 +27,9 @@ void of_register_i2c_devices(struct i2c_adapter *adap, const u32 *addr; int len; + if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) + continue; + addr = of_get_property(node, "reg", &len); if (!addr || len < sizeof(int) || *addr > (1 << 10) - 1) { printk(KERN_ERR @@ -92,11 +39,6 @@ void of_register_i2c_devices(struct i2c_adapter *adap, info.irq = irq_of_parse_and_map(node, 0); - if (of_find_i2c_driver(node, &info) < 0) { - irq_dispose_mapping(info.irq); - continue; - } - info.addr = *addr; request_module(info.type); diff --git a/include/linux/of.h b/include/linux/of.h index 59a61bdc98b6..79886ade070f 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -70,5 +70,6 @@ extern int of_n_addr_cells(struct device_node *np); extern int of_n_size_cells(struct device_node *np); extern const struct of_device_id *of_match_node( const struct of_device_id *matches, const struct device_node *node); +extern int of_modalias_node(struct device_node *node, char *modalias, int len); #endif /* _LINUX_OF_H */ |
