diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index 1d7ec3129349b2cefeee64afd68fb92ae85a17e5..f821dbc952a42bb2e53a49c110decc859eff3d55 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -13,3 +13,9 @@ config OF_I2C depends on PPC_OF && I2C help OpenFirmware I2C accessors + +config OF_SPI + def_tristate SPI + depends on OF && PPC_OF && SPI + help + OpenFirmware SPI accessors diff --git a/drivers/of/Makefile b/drivers/of/Makefile index 548772e871fd8e52a1ed66156fc0c129e84660af..4c3c6f8e36f51577281f881f6edf464834847111 100644 --- a/drivers/of/Makefile +++ b/drivers/of/Makefile @@ -2,3 +2,4 @@ obj-y = base.o obj-$(CONFIG_OF_DEVICE) += device.o platform.o obj-$(CONFIG_OF_GPIO) += gpio.o obj-$(CONFIG_OF_I2C) += of_i2c.o +obj-$(CONFIG_OF_SPI) += of_spi.o diff --git a/drivers/of/base.c b/drivers/of/base.c index 23ffb7c0caf24148277ddd19c7430b5c90fb6fcb..ad8ac1a8af28689acc7198b22fe95a888d62e6a6 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," 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, 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 344e1b03dd8b708661fcb08982d27ebd79bd586b..6a98dc8aa30b1af9a1e8ce9a2a8264073a631eee 100644 --- a/drivers/of/of_i2c.c +++ b/drivers/of/of_i2c.c @@ -16,62 +16,6 @@ #include #include -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, 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/drivers/of/of_spi.c b/drivers/of/of_spi.c new file mode 100644 index 0000000000000000000000000000000000000000..b01eec026f68b3f8765bd50d35070757b1795785 --- /dev/null +++ b/drivers/of/of_spi.c @@ -0,0 +1,93 @@ +/* + * SPI OF support routines + * Copyright (C) 2008 Secret Lab Technologies Ltd. + * + * Support routines for deriving SPI device attachments from the device + * tree. + */ + +#include +#include +#include +#include + +/** + * of_register_spi_devices - Register child devices onto the SPI bus + * @master: Pointer to spi_master device + * @np: parent node of SPI device nodes + * + * Registers an spi_device for each child node of 'np' which has a 'reg' + * property. + */ +void of_register_spi_devices(struct spi_master *master, struct device_node *np) +{ + struct spi_device *spi; + struct device_node *nc; + const u32 *prop; + int rc; + int len; + + for_each_child_of_node(np, nc) { + /* Alloc an spi_device */ + spi = spi_alloc_device(master); + if (!spi) { + dev_err(&master->dev, "spi_device alloc error for %s\n", + nc->full_name); + spi_dev_put(spi); + continue; + } + + /* Select device driver */ + if (of_modalias_node(nc, spi->modalias, + sizeof(spi->modalias)) < 0) { + dev_err(&master->dev, "cannot find modalias for %s\n", + nc->full_name); + spi_dev_put(spi); + continue; + } + + /* Device address */ + prop = of_get_property(nc, "reg", &len); + if (!prop || len < sizeof(*prop)) { + dev_err(&master->dev, "%s has no 'reg' property\n", + nc->full_name); + spi_dev_put(spi); + continue; + } + spi->chip_select = *prop; + + /* Mode (clock phase/polarity/etc.) */ + if (of_find_property(nc, "spi-cpha", NULL)) + spi->mode |= SPI_CPHA; + if (of_find_property(nc, "spi-cpol", NULL)) + spi->mode |= SPI_CPOL; + + /* Device speed */ + prop = of_get_property(nc, "spi-max-frequency", &len); + if (!prop || len < sizeof(*prop)) { + dev_err(&master->dev, "%s has no 'spi-max-frequency' property\n", + nc->full_name); + spi_dev_put(spi); + continue; + } + spi->max_speed_hz = *prop; + + /* IRQ */ + spi->irq = irq_of_parse_and_map(nc, 0); + + /* Store a pointer to the node in the device structure */ + of_node_get(nc); + spi->dev.archdata.of_node = nc; + + /* Register the new device */ + request_module(spi->modalias); + rc = spi_add_device(spi); + if (rc) { + dev_err(&master->dev, "spi_device register error %s\n", + nc->full_name); + spi_dev_put(spi); + } + + } +} +EXPORT_SYMBOL(of_register_spi_devices); diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ecca4a6a6f94a8b02e9d8143ae2be88d11bd00b5..964124b60db2560b12f15d08dbdeeff43a058e16 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -178,6 +178,96 @@ struct boardinfo { static LIST_HEAD(board_list); static DEFINE_MUTEX(board_lock); +/** + * spi_alloc_device - Allocate a new SPI device + * @master: Controller to which device is connected + * Context: can sleep + * + * Allows a driver to allocate and initialize a spi_device without + * registering it immediately. This allows a driver to directly + * fill the spi_device with device parameters before calling + * spi_add_device() on it. + * + * Caller is responsible to call spi_add_device() on the returned + * spi_device structure to add it to the SPI master. If the caller + * needs to discard the spi_device without adding it, then it should + * call spi_dev_put() on it. + * + * Returns a pointer to the new device, or NULL. + */ +struct spi_device *spi_alloc_device(struct spi_master *master) +{ + struct spi_device *spi; + struct device *dev = master->dev.parent; + + if (!spi_master_get(master)) + return NULL; + + spi = kzalloc(sizeof *spi, GFP_KERNEL); + if (!spi) { + dev_err(dev, "cannot alloc spi_device\n"); + spi_master_put(master); + return NULL; + } + + spi->master = master; + spi->dev.parent = dev; + spi->dev.bus = &spi_bus_type; + spi->dev.release = spidev_release; + device_initialize(&spi->dev); + return spi; +} +EXPORT_SYMBOL_GPL(spi_alloc_device); + +/** + * spi_add_device - Add spi_device allocated with spi_alloc_device + * @spi: spi_device to register + * + * Companion function to spi_alloc_device. Devices allocated with + * spi_alloc_device can be added onto the spi bus with this function. + * + * Returns 0 on success; non-zero on failure + */ +int spi_add_device(struct spi_device *spi) +{ + struct device *dev = spi->master->dev.parent; + int status; + + /* Chipselects are numbered 0..max; validate. */ + if (spi->chip_select >= spi->master->num_chipselect) { + dev_err(dev, "cs%d >= max %d\n", + spi->chip_select, + spi->master->num_chipselect); + return -EINVAL; + } + + /* Set the bus ID string */ + snprintf(spi->dev.bus_id, sizeof spi->dev.bus_id, + "%s.%u", spi->master->dev.bus_id, + spi->chip_select); + + /* drivers may modify this initial i/o setup */ + status = spi->master->setup(spi); + if (status < 0) { + dev_err(dev, "can't %s %s, status %d\n", + "setup", spi->dev.bus_id, status); + return status; + } + + /* driver core catches callers that misbehave by defining + * devices that already exist. + */ + status = device_add(&spi->dev); + if (status < 0) { + dev_err(dev, "can't %s %s, status %d\n", + "add", spi->dev.bus_id, status); + return status; + } + + dev_dbg(dev, "registered child %s\n", spi->dev.bus_id); + return 0; +} +EXPORT_SYMBOL_GPL(spi_add_device); /** * spi_new_device - instantiate one new SPI device @@ -197,7 +287,6 @@ struct spi_device *spi_new_device(struct spi_master *master, struct spi_board_info *chip) { struct spi_device *proxy; - struct device *dev = master->dev.parent; int status; /* NOTE: caller did any chip->bus_num checks necessary. @@ -207,66 +296,28 @@ struct spi_device *spi_new_device(struct spi_master *master, * suggests syslogged diagnostics are best here (ugh). */ - /* Chipselects are numbered 0..max; validate. */ - if (chip->chip_select >= master->num_chipselect) { - dev_err(dev, "cs%d > max %d\n", - chip->chip_select, - master->num_chipselect); - return NULL; - } - - if (!spi_master_get(master)) + proxy = spi_alloc_device(master); + if (!proxy) return NULL; WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); - proxy = kzalloc(sizeof *proxy, GFP_KERNEL); - if (!proxy) { - dev_err(dev, "can't alloc dev for cs%d\n", - chip->chip_select); - goto fail; - } - proxy->master = master; proxy->chip_select = chip->chip_select; proxy->max_speed_hz = chip->max_speed_hz; proxy->mode = chip->mode; proxy->irq = chip->irq; strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); - - snprintf(proxy->dev.bus_id, sizeof proxy->dev.bus_id, - "%s.%u", master->dev.bus_id, - chip->chip_select); - proxy->dev.parent = dev; - proxy->dev.bus = &spi_bus_type; proxy->dev.platform_data = (void *) chip->platform_data; proxy->controller_data = chip->controller_data; proxy->controller_state = NULL; - proxy->dev.release = spidev_release; - /* drivers may modify this initial i/o setup */ - status = master->setup(proxy); + status = spi_add_device(proxy); if (status < 0) { - dev_err(dev, "can't %s %s, status %d\n", - "setup", proxy->dev.bus_id, status); - goto fail; + spi_dev_put(proxy); + return NULL; } - /* driver core catches callers that misbehave by defining - * devices that already exist. - */ - status = device_register(&proxy->dev); - if (status < 0) { - dev_err(dev, "can't %s %s, status %d\n", - "add", proxy->dev.bus_id, status); - goto fail; - } - dev_dbg(dev, "registered child %s\n", proxy->dev.bus_id); return proxy; - -fail: - spi_master_put(master); - kfree(proxy); - return NULL; } EXPORT_SYMBOL_GPL(spi_new_device); diff --git a/include/linux/of.h b/include/linux/of.h index 59a61bdc98b69b58da4f6f9797c131a275c690d1..79886ade070f2e791274c92814bc04bfbcff4947 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 */ diff --git a/include/linux/of_spi.h b/include/linux/of_spi.h new file mode 100644 index 0000000000000000000000000000000000000000..5f71ee8c0868d6d549ded2ca2ffbbfa837160584 --- /dev/null +++ b/include/linux/of_spi.h @@ -0,0 +1,18 @@ +/* + * OpenFirmware SPI support routines + * Copyright (C) 2008 Secret Lab Technologies Ltd. + * + * Support routines for deriving SPI device attachments from the device + * tree. + */ + +#ifndef __LINUX_OF_SPI_H +#define __LINUX_OF_SPI_H + +#include +#include + +extern void of_register_spi_devices(struct spi_master *master, + struct device_node *np); + +#endif /* __LINUX_OF_SPI */ diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index a9cc29d466535f64b7f3cccdcc25c5f43cd96a40..4be01bb4437748c27f80aa79733c3a1360ca13e0 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -778,7 +778,19 @@ spi_register_board_info(struct spi_board_info const *info, unsigned n) * use spi_new_device() to describe each device. You can also call * spi_unregister_device() to start making that device vanish, but * normally that would be handled by spi_unregister_master(). + * + * You can also use spi_alloc_device() and spi_add_device() to use a two + * stage registration sequence for each spi_device. This gives the caller + * some more control over the spi_device structure before it is registered, + * but requires that caller to initialize fields that would otherwise + * be defined using the board info. */ +extern struct spi_device * +spi_alloc_device(struct spi_master *master); + +extern int +spi_add_device(struct spi_device *spi); + extern struct spi_device * spi_new_device(struct spi_master *, struct spi_board_info *);