[PATCHv3 2/4] mc13xxx: Add spi driver

[Marc Reilly]

Adds spi specific code for mc13xxx.
Most code extracted from the previous mc13xxx-core.c

Signed-off-by: Marc Reilly <marc at cpdesign.com.au>
---
 drivers/mfd/mc13xxx-spi.c |  168 +++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 168 insertions(+), 0 deletions(-)
 create mode 100644 drivers/mfd/mc13xxx-spi.c

diff --git a/drivers/mfd/mc13xxx-spi.c b/drivers/mfd/mc13xxx-spi.c
new file mode 100644
index 0000000..de832ea
--- /dev/null
+++ b/drivers/mfd/mc13xxx-spi.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright 2009-2010 Pengutronix
+ * Uwe Kleine-Koenig <u.kleine-koenig at pengutronix.de>
+ *
+ * loosely based on an earlier driver that has
+ * Copyright 2009 Pengutronix, Sascha Hauer <s.hauer at pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mc13xxx.h>
+
+#define MC13XXX_REGOFFSET_SHIFT 25
+static int mc13xxx_spi_reg_read(struct mc13xxx *mc13xxx,
+				unsigned int offset, u32 *val)
+{
+	struct spi_transfer t;
+	struct spi_message m;
+	int ret;
+
+	*val = offset << MC13XXX_REGOFFSET_SHIFT;
+
+	memset(&t, 0, sizeof(t));
+
+	t.tx_buf = val;
+	t.rx_buf = val;
+	t.len = sizeof(u32);
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t, &m);
+
+	ret = spi_sync(mc13xxx->spidev, &m);
+
+	/* error in message.status implies error return from spi_sync */
+	BUG_ON(!ret && m.status);
+
+	if (ret)
+		return ret;
+
+	*val &= 0xffffff;
+
+	return 0;
+}
+
+static int mc13xxx_spi_reg_write(struct mc13xxx *mc13xxx, unsigned int offset,
+		u32 val)
+{
+	u32 buf;
+	struct spi_transfer t;
+	struct spi_message m;
+	int ret;
+
+	buf = 1 << 31 | offset << MC13XXX_REGOFFSET_SHIFT | val;
+
+	memset(&t, 0, sizeof(t));
+
+	t.tx_buf = &buf;
+	t.rx_buf = &buf;
+	t.len = sizeof(u32);
+
+	spi_message_init(&m);
+	spi_message_add_tail(&t, &m);
+
+	ret = spi_sync(mc13xxx->spidev, &m);
+
+	BUG_ON(!ret && m.status);
+
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int mc13xxx_spi_probe(struct spi_device *spi)
+{
+	struct mc13xxx *mc13xxx;
+	struct mc13xxx_platform_data *pdata = dev_get_platdata(&spi->dev);
+	int ret;
+
+	mc13xxx = kzalloc(sizeof(*mc13xxx), GFP_KERNEL);
+	if (!mc13xxx)
+		return -ENOMEM;
+
+	dev_set_drvdata(&spi->dev, mc13xxx);
+	spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
+	spi->bits_per_word = 32;
+	spi_setup(spi);
+
+	mc13xxx->dev = &spi->dev;
+	mc13xxx->spidev = spi;
+	mc13xxx->read_dev = mc13xxx_spi_reg_read;
+	mc13xxx->write_dev = mc13xxx_spi_reg_write;
+
+	ret = mc13xxx_common_init(mc13xxx, pdata, spi->irq);
+
+	if (ret) {
+		dev_set_drvdata(&spi->dev, NULL);
+	} else {
+		const struct spi_device_id *devid =
+			spi_get_device_id(mc13xxx->spidev);
+		if (!devid || devid->driver_data != mc13xxx->ictype)
+			dev_warn(mc13xxx->dev,
+				"device id doesn't match auto detection!\n");
+	}
+
+	return ret;
+}
+
+
+static int __devexit mc13xxx_spi_remove(struct spi_device *spi)
+{
+	struct mc13xxx *mc13xxx = dev_get_drvdata(&spi->dev);
+
+	free_irq(spi->irq, mc13xxx);
+
+	mfd_remove_devices(&spi->dev);
+
+	kfree(mc13xxx);
+
+	return 0;
+}
+
+static const struct spi_device_id mc13xxx_device_id[] = {
+	{
+		.name = "mc13783",
+		.driver_data = MC13XXX_ID_MC13783,
+	}, {
+		.name = "mc13892",
+		.driver_data = MC13XXX_ID_MC13892,
+	}, {
+		/* sentinel */
+	}
+};
+
+static struct spi_driver mc13xxx_driver = {
+	.id_table = mc13xxx_device_id,
+	.driver = {
+		.name = "mc13xxx",
+		.bus = &spi_bus_type,
+		.owner = THIS_MODULE,
+	},
+	.probe = mc13xxx_spi_probe,
+	.remove = __devexit_p(mc13xxx_spi_remove),
+};
+
+static int __init mc13xxx_spi_init(void)
+{
+	return spi_register_driver(&mc13xxx_driver);
+}
+subsys_initcall(mc13xxx_spi_init);
+
+static void __exit mc13xxx_spi_exit(void)
+{
+	spi_unregister_driver(&mc13xxx_driver);
+}
+module_exit(mc13xxx_spi_exit);
+
+MODULE_DESCRIPTION("spi driver for Freescale MC13XXX PMIC");
+MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig at pengutronix.de>");
+MODULE_LICENSE("GPL v2");
-- 
1.7.1