diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/of/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/of/Makefile | 1 | ||||
| -rw-r--r-- | drivers/of/of_spi.c | 93 |
3 files changed, 100 insertions, 0 deletions
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index 1d7ec3129349..f821dbc952a4 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 548772e871fd..4c3c6f8e36f5 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/of_spi.c b/drivers/of/of_spi.c new file mode 100644 index 000000000000..b01eec026f68 --- /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 <linux/of.h> +#include <linux/device.h> +#include <linux/spi/spi.h> +#include <linux/of_spi.h> + +/** + * 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); |