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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /drivers/of/of_spi.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'drivers/of/of_spi.c')
-rw-r--r--drivers/of/of_spi.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/of/of_spi.c b/drivers/of/of_spi.c
new file mode 100644
index 00000000..6dbc074e
--- /dev/null
+++ b/drivers/of/of_spi.c
@@ -0,0 +1,99 @@
+/*
+ * SPI OF support routines
+ * Copyright (C) 2008 Secret Lab Technologies Ltd.
+ *
+ * Support routines for deriving SPI device attachments from the device
+ * tree.
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/of_irq.h>
+#include <linux/of_spi.h>
+
+/**
+ * of_register_spi_devices - Register child devices onto the SPI bus
+ * @master: Pointer to spi_master device
+ *
+ * Registers an spi_device for each child node of master node which has a 'reg'
+ * property.
+ */
+void of_register_spi_devices(struct spi_master *master)
+{
+ struct spi_device *spi;
+ struct device_node *nc;
+ const __be32 *prop;
+ int rc;
+ int len;
+
+ if (!master->dev.of_node)
+ return;
+
+ for_each_child_of_node(master->dev.of_node, 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 = be32_to_cpup(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;
+ if (of_find_property(nc, "spi-cs-high", NULL))
+ spi->mode |= SPI_CS_HIGH;
+
+ /* 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 = be32_to_cpup(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.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);