summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/of/Kconfig6
-rw-r--r--drivers/of/Makefile1
-rw-r--r--drivers/of/of_spi.c93
-rw-r--r--include/linux/of_spi.h18
4 files changed, 118 insertions, 0 deletions
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 1d7ec31..f821dbc 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 548772e..4c3c6f8 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 0000000..b01eec0
--- /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);
diff --git a/include/linux/of_spi.h b/include/linux/of_spi.h
new file mode 100644
index 0000000..5f71ee8
--- /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 <linux/of.h>
+#include <linux/spi/spi.h>
+
+extern void of_register_spi_devices(struct spi_master *master,
+ struct device_node *np);
+
+#endif /* __LINUX_OF_SPI */
OpenPOWER on IntegriCloud