[linux-2.6-block.git] / drivers / of / of_spi.c

/*
 * 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);
Commit	Line	Data
284b0189 GL	1	/*
	2	* SPI OF support routines
	3	* Copyright (C) 2008 Secret Lab Technologies Ltd.
	4	*
	5	* Support routines for deriving SPI device attachments from the device
	6	* tree.
	7	*/
	8
48a9e412	9	#include <linux/module.h>
284b0189 GL	10	#include <linux/of.h>
	11	#include <linux/device.h>
	12	#include <linux/spi/spi.h>
e3873444	13	#include <linux/of_irq.h>
284b0189 GL	14	#include <linux/of_spi.h>
	15
	16	/**
	17	* of_register_spi_devices - Register child devices onto the SPI bus
	18	* @master: Pointer to spi_master device
284b0189	19	*
12b15e83	20	* Registers an spi_device for each child node of master node which has a 'reg'
284b0189 GL	21	* property.
284b0189 GL	22	*/
12b15e83	23	void of_register_spi_devices(struct spi_master *master)
284b0189 GL	24	{
	25	struct spi_device *spi;
	26	struct device_node *nc;
33714881	27	const __be32 *prop;
284b0189 GL	28	int rc;
	29	int len;
	30
12b15e83 AG	31	if (!master->dev.of_node)
	32	return;
	33
	34	for_each_child_of_node(master->dev.of_node, nc) {
284b0189 GL	35	/* Alloc an spi_device */
	36	spi = spi_alloc_device(master);
	37	if (!spi) {
	38	dev_err(&master->dev, "spi_device alloc error for %s\n",
	39	nc->full_name);
	40	spi_dev_put(spi);
	41	continue;
	42	}
	43
	44	/* Select device driver */
	45	if (of_modalias_node(nc, spi->modalias,
	46	sizeof(spi->modalias)) < 0) {
	47	dev_err(&master->dev, "cannot find modalias for %s\n",
	48	nc->full_name);
	49	spi_dev_put(spi);
	50	continue;
	51	}
	52
	53	/* Device address */
	54	prop = of_get_property(nc, "reg", &len);
	55	if (!prop \|\| len < sizeof(*prop)) {
	56	dev_err(&master->dev, "%s has no 'reg' property\n",
	57	nc->full_name);
	58	spi_dev_put(spi);
	59	continue;
	60	}
33714881	61	spi->chip_select = be32_to_cpup(prop);
284b0189 GL	62
	63	/* Mode (clock phase/polarity/etc.) */
	64	if (of_find_property(nc, "spi-cpha", NULL))
	65	spi->mode \|= SPI_CPHA;
	66	if (of_find_property(nc, "spi-cpol", NULL))
	67	spi->mode \|= SPI_CPOL;
f618ebfc WO	68	if (of_find_property(nc, "spi-cs-high", NULL))
f618ebfc WO	69	spi->mode \|= SPI_CS_HIGH;
284b0189 GL	70
	71	/* Device speed */
	72	prop = of_get_property(nc, "spi-max-frequency", &len);
	73	if (!prop \|\| len < sizeof(*prop)) {
	74	dev_err(&master->dev, "%s has no 'spi-max-frequency' property\n",
	75	nc->full_name);
	76	spi_dev_put(spi);
	77	continue;
	78	}
33714881	79	spi->max_speed_hz = be32_to_cpup(prop);
284b0189 GL	80
	81	/* IRQ */
	82	spi->irq = irq_of_parse_and_map(nc, 0);
	83
	84	/* Store a pointer to the node in the device structure */
	85	of_node_get(nc);
d706c1b0	86	spi->dev.of_node = nc;
284b0189 GL	87
	88	/* Register the new device */
	89	request_module(spi->modalias);
	90	rc = spi_add_device(spi);
	91	if (rc) {
	92	dev_err(&master->dev, "spi_device register error %s\n",
	93	nc->full_name);
	94	spi_dev_put(spi);
	95	}
	96
	97	}
	98	}
	99	EXPORT_SYMBOL(of_register_spi_devices);