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authorLinus Torvalds <torvalds@linux-foundation.org>2008-07-28 09:05:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-28 09:05:35 -0700
commitd9089c296bdd82e6c1b7f82d04c11b5decde75e7 (patch)
tree6c2a3b8bc1b6f8b5930f6a20b099511dd19aa4ba /drivers/of/of_spi.c
parentbda426f5310ffddcd463fe20f352609e84989514 (diff)
parent00df438e89a9003895948170e1abf64dd4665872 (diff)
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits) powerpc: Disable 64K hugetlb support when doing 64K SPU mappings powerpc/powermac: Fixup default serial port device for pmac_zilog powerpc/powermac: Use sane default baudrate for SCC debugging powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 64-bit powerpc: Show processor cache information in sysfs powerpc: Make core id information available to userspace powerpc: Make core sibling information available to userspace powerpc/vio: More fallout from dma_mapping_error API change ibmveth: Fix multiple errors with dma_mapping_error conversion powerpc/pseries: Fix CMO sysdev attribute API change fallout powerpc: Enable tracehook for the architecture powerpc: Add TIF_NOTIFY_RESUME support for tracehook powerpc: Add asm/syscall.h with the tracehook entry points powerpc: Make syscall tracing use tracehook.h helpers powerpc: Call tracehook_signal_handler() when setting up signal frames powerpc: Update cpu_sibling_maps dynamically powerpc: register_cpu_online should be __cpuinit powerpc: kill useless SMT code in prom_hold_cpus powerpc: Fix 8xx build failure powerpc: Fix vio build warnings ...
Diffstat (limited to 'drivers/of/of_spi.c')
-rw-r--r--drivers/of/of_spi.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/drivers/of/of_spi.c b/drivers/of/of_spi.c
new file mode 100644
index 00000000000..b01eec026f6
--- /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);