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48a9e412b6
This file really needs the full module.h header file present, but was just getting it implicitly before. Fix it up in advance so we avoid build failures once the cleanup commit is present. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
100 lines
2.4 KiB
C
100 lines
2.4 KiB
C
/*
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* SPI OF support routines
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* Copyright (C) 2008 Secret Lab Technologies Ltd.
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*
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* Support routines for deriving SPI device attachments from the device
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* tree.
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*/
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/device.h>
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#include <linux/spi/spi.h>
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#include <linux/of_irq.h>
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#include <linux/of_spi.h>
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/**
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* of_register_spi_devices - Register child devices onto the SPI bus
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* @master: Pointer to spi_master device
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*
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* Registers an spi_device for each child node of master node which has a 'reg'
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* property.
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*/
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void of_register_spi_devices(struct spi_master *master)
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{
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struct spi_device *spi;
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struct device_node *nc;
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const __be32 *prop;
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int rc;
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int len;
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if (!master->dev.of_node)
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return;
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for_each_child_of_node(master->dev.of_node, nc) {
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/* Alloc an spi_device */
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spi = spi_alloc_device(master);
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if (!spi) {
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dev_err(&master->dev, "spi_device alloc error for %s\n",
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nc->full_name);
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spi_dev_put(spi);
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continue;
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}
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/* Select device driver */
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if (of_modalias_node(nc, spi->modalias,
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sizeof(spi->modalias)) < 0) {
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dev_err(&master->dev, "cannot find modalias for %s\n",
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nc->full_name);
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spi_dev_put(spi);
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continue;
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}
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/* Device address */
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prop = of_get_property(nc, "reg", &len);
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if (!prop || len < sizeof(*prop)) {
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dev_err(&master->dev, "%s has no 'reg' property\n",
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nc->full_name);
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spi_dev_put(spi);
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continue;
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}
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spi->chip_select = be32_to_cpup(prop);
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/* Mode (clock phase/polarity/etc.) */
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if (of_find_property(nc, "spi-cpha", NULL))
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spi->mode |= SPI_CPHA;
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if (of_find_property(nc, "spi-cpol", NULL))
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spi->mode |= SPI_CPOL;
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if (of_find_property(nc, "spi-cs-high", NULL))
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spi->mode |= SPI_CS_HIGH;
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/* Device speed */
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prop = of_get_property(nc, "spi-max-frequency", &len);
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if (!prop || len < sizeof(*prop)) {
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dev_err(&master->dev, "%s has no 'spi-max-frequency' property\n",
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nc->full_name);
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spi_dev_put(spi);
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continue;
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}
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spi->max_speed_hz = be32_to_cpup(prop);
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/* IRQ */
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spi->irq = irq_of_parse_and_map(nc, 0);
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/* Store a pointer to the node in the device structure */
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of_node_get(nc);
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spi->dev.of_node = nc;
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/* Register the new device */
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request_module(spi->modalias);
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rc = spi_add_device(spi);
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if (rc) {
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dev_err(&master->dev, "spi_device register error %s\n",
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nc->full_name);
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spi_dev_put(spi);
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}
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}
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}
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EXPORT_SYMBOL(of_register_spi_devices);
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