Merge branch 'merge'

1 files changed, 483 insertions, 0 deletions

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
new file mode 100644
index 00000000000..5d92a7e5cb4
--- /dev/null
+++ b/drivers/spi/spi_mpc83xx.c
@@ -0,0 +1,483 @@
+/*
+ * MPC83xx SPI controller driver.
+ *
+ * Maintainer: Kumar Gala
+ *
+ * Copyright (C) 2006 Polycom, Inc.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/platform_device.h>
+#include <linux/fsl_devices.h>
+
+#include <asm/irq.h>
+#include <asm/io.h>
+
+/* SPI Controller registers */
+struct mpc83xx_spi_reg {
+	u8 res1[0x20];
+	__be32 mode;
+	__be32 event;
+	__be32 mask;
+	__be32 command;
+	__be32 transmit;
+	__be32 receive;
+};
+
+/* SPI Controller mode register definitions */
+#define	SPMODE_CI_INACTIVEHIGH	(1 << 29)
+#define	SPMODE_CP_BEGIN_EDGECLK	(1 << 28)
+#define	SPMODE_DIV16		(1 << 27)
+#define	SPMODE_REV		(1 << 26)
+#define	SPMODE_MS		(1 << 25)
+#define	SPMODE_ENABLE		(1 << 24)
+#define	SPMODE_LEN(x)		((x) << 20)
+#define	SPMODE_PM(x)		((x) << 16)
+
+/*
+ * Default for SPI Mode:
+ * 	SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk
+ */
+#define	SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \
+			 SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf))
+
+/* SPIE register values */
+#define	SPIE_NE		0x00000200	/* Not empty */
+#define	SPIE_NF		0x00000100	/* Not full */
+
+/* SPIM register values */
+#define	SPIM_NE		0x00000200	/* Not empty */
+#define	SPIM_NF		0x00000100	/* Not full */
+
+/* SPI Controller driver's private data. */
+struct mpc83xx_spi {
+	/* bitbang has to be first */
+	struct spi_bitbang bitbang;
+	struct completion done;
+
+	struct mpc83xx_spi_reg __iomem *base;
+
+	/* rx & tx bufs from the spi_transfer */
+	const void *tx;
+	void *rx;
+
+	/* functions to deal with different sized buffers */
+	void (*get_rx) (u32 rx_data, struct mpc83xx_spi *);
+	u32(*get_tx) (struct mpc83xx_spi *);
+
+	unsigned int count;
+	u32 irq;
+
+	unsigned nsecs;		/* (clock cycle time)/2 */
+
+	u32 sysclk;
+	void (*activate_cs) (u8 cs, u8 polarity);
+	void (*deactivate_cs) (u8 cs, u8 polarity);
+};
+
+static inline void mpc83xx_spi_write_reg(__be32 __iomem * reg, u32 val)
+{
+	out_be32(reg, val);
+}
+
+static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg)
+{
+	return in_be32(reg);
+}
+
+#define MPC83XX_SPI_RX_BUF(type) 					  \
+void mpc83xx_spi_rx_buf_##type(u32 data, struct mpc83xx_spi *mpc83xx_spi) \
+{									  \
+	type * rx = mpc83xx_spi->rx;					  \
+	*rx++ = (type)data;						  \
+	mpc83xx_spi->rx = rx;						  \
+}
+
+#define MPC83XX_SPI_TX_BUF(type)				\
+u32 mpc83xx_spi_tx_buf_##type(struct mpc83xx_spi *mpc83xx_spi)	\
+{								\
+	u32 data;						\
+	const type * tx = mpc83xx_spi->tx;			\
+	data = *tx++;						\
+	mpc83xx_spi->tx = tx;					\
+	return data;						\
+}
+
+MPC83XX_SPI_RX_BUF(u8)
+MPC83XX_SPI_RX_BUF(u16)
+MPC83XX_SPI_RX_BUF(u32)
+MPC83XX_SPI_TX_BUF(u8)
+MPC83XX_SPI_TX_BUF(u16)
+MPC83XX_SPI_TX_BUF(u32)
+
+static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
+{
+	struct mpc83xx_spi *mpc83xx_spi;
+	u8 pol = spi->mode & SPI_CS_HIGH ? 1 : 0;
+
+	mpc83xx_spi = spi_master_get_devdata(spi->master);
+
+	if (value == BITBANG_CS_INACTIVE) {
+		if (mpc83xx_spi->deactivate_cs)
+			mpc83xx_spi->deactivate_cs(spi->chip_select, pol);
+	}
+
+	if (value == BITBANG_CS_ACTIVE) {
+		u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
+		u32 len = spi->bits_per_word;
+		if (len == 32)
+			len = 0;
+		else
+			len = len - 1;
+
+		/* mask out bits we are going to set */
+		regval &= ~0x38ff0000;
+
+		if (spi->mode & SPI_CPHA)
+			regval |= SPMODE_CP_BEGIN_EDGECLK;
+		if (spi->mode & SPI_CPOL)
+			regval |= SPMODE_CI_INACTIVEHIGH;
+
+		regval |= SPMODE_LEN(len);
+
+		if ((mpc83xx_spi->sysclk / spi->max_speed_hz) >= 64) {
+			u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 64);
+			regval |= SPMODE_PM(pm) | SPMODE_DIV16;
+		} else {
+			u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 4);
+			regval |= SPMODE_PM(pm);
+		}
+
+		mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
+		if (mpc83xx_spi->activate_cs)
+			mpc83xx_spi->activate_cs(spi->chip_select, pol);
+	}
+}
+
+static
+int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
+{
+	struct mpc83xx_spi *mpc83xx_spi;
+	u32 regval;
+	u8 bits_per_word;
+	u32 hz;
+
+	mpc83xx_spi = spi_master_get_devdata(spi->master);
+
+	if (t) {
+		bits_per_word = t->bits_per_word;
+		hz = t->speed_hz;
+	} else {
+		bits_per_word = 0;
+		hz = 0;
+	}
+
+	/* spi_transfer level calls that work per-word */
+	if (!bits_per_word)
+		bits_per_word = spi->bits_per_word;
+
+	/* Make sure its a bit width we support [4..16, 32] */
+	if ((bits_per_word < 4)
+	    || ((bits_per_word > 16) && (bits_per_word != 32)))
+		return -EINVAL;
+
+	if (bits_per_word <= 8) {
+		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
+		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
+	} else if (bits_per_word <= 16) {
+		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u16;
+		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u16;
+	} else if (bits_per_word <= 32) {
+		mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u32;
+		mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u32;
+	} else
+		return -EINVAL;
+
+	/* nsecs = (clock period)/2 */
+	if (!hz)
+		hz = spi->max_speed_hz;
+	mpc83xx_spi->nsecs = (1000000000 / 2) / hz;
+	if (mpc83xx_spi->nsecs > MAX_UDELAY_MS * 1000)
+		return -EINVAL;
+
+	if (bits_per_word == 32)
+		bits_per_word = 0;
+	else
+		bits_per_word = bits_per_word - 1;
+
+	regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
+
+	/* Mask out bits_per_wordgth */
+	regval &= 0xff0fffff;
+	regval |= SPMODE_LEN(bits_per_word);
+
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
+
+	return 0;
+}
+
+static int mpc83xx_spi_setup(struct spi_device *spi)
+{
+	struct spi_bitbang *bitbang;
+	struct mpc83xx_spi *mpc83xx_spi;
+	int retval;
+
+	if (!spi->max_speed_hz)
+		return -EINVAL;
+
+	bitbang = spi_master_get_devdata(spi->master);
+	mpc83xx_spi = spi_master_get_devdata(spi->master);
+
+	if (!spi->bits_per_word)
+		spi->bits_per_word = 8;
+
+	retval = mpc83xx_spi_setup_transfer(spi, NULL);
+	if (retval < 0)
+		return retval;
+
+	dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u nsec\n",
+		__FUNCTION__, spi->mode & (SPI_CPOL | SPI_CPHA),
+		spi->bits_per_word, 2 * mpc83xx_spi->nsecs);
+
+	/* NOTE we _need_ to call chipselect() early, ideally with adapter
+	 * setup, unless the hardware defaults cooperate to avoid confusion
+	 * between normal (active low) and inverted chipselects.
+	 */
+
+	/* deselect chip (low or high) */
+	spin_lock(&bitbang->lock);
+	if (!bitbang->busy) {
+		bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
+		ndelay(mpc83xx_spi->nsecs);
+	}
+	spin_unlock(&bitbang->lock);
+
+	return 0;
+}
+
+static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
+{
+	struct mpc83xx_spi *mpc83xx_spi;
+	u32 word;
+
+	mpc83xx_spi = spi_master_get_devdata(spi->master);
+
+	mpc83xx_spi->tx = t->tx_buf;
+	mpc83xx_spi->rx = t->rx_buf;
+	mpc83xx_spi->count = t->len;
+	INIT_COMPLETION(mpc83xx_spi->done);
+
+	/* enable rx ints */
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE);
+
+	/* transmit word */
+	word = mpc83xx_spi->get_tx(mpc83xx_spi);
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word);
+
+	wait_for_completion(&mpc83xx_spi->done);
+
+	/* disable rx ints */
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
+
+	return t->len - mpc83xx_spi->count;
+}
+
+irqreturn_t mpc83xx_spi_irq(s32 irq, void *context_data,
+			    struct pt_regs * ptregs)
+{
+	struct mpc83xx_spi *mpc83xx_spi = context_data;
+	u32 event;
+	irqreturn_t ret = IRQ_NONE;
+
+	/* Get interrupt events(tx/rx) */
+	event = mpc83xx_spi_read_reg(&mpc83xx_spi->base->event);
+
+	/* We need handle RX first */
+	if (event & SPIE_NE) {
+		u32 rx_data = mpc83xx_spi_read_reg(&mpc83xx_spi->base->receive);
+
+		if (mpc83xx_spi->rx)
+			mpc83xx_spi->get_rx(rx_data, mpc83xx_spi);
+
+		ret = IRQ_HANDLED;
+	}
+
+	if ((event & SPIE_NF) == 0)
+		/* spin until TX is done */
+		while (((event =
+			 mpc83xx_spi_read_reg(&mpc83xx_spi->base->event)) &
+						SPIE_NF) == 0)
+			 cpu_relax();
+
+	mpc83xx_spi->count -= 1;
+	if (mpc83xx_spi->count) {
+		if (mpc83xx_spi->tx) {
+			u32 word = mpc83xx_spi->get_tx(mpc83xx_spi);
+			mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit,
+					      word);
+		}
+	} else {
+		complete(&mpc83xx_spi->done);
+	}
+
+	/* Clear the events */
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, event);
+
+	return ret;
+}
+
+static int __init mpc83xx_spi_probe(struct platform_device *dev)
+{
+	struct spi_master *master;
+	struct mpc83xx_spi *mpc83xx_spi;
+	struct fsl_spi_platform_data *pdata;
+	struct resource *r;
+	u32 regval;
+	int ret = 0;
+
+	/* Get resources(memory, IRQ) associated with the device */
+	master = spi_alloc_master(&dev->dev, sizeof(struct mpc83xx_spi));
+
+	if (master == NULL) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	platform_set_drvdata(dev, master);
+	pdata = dev->dev.platform_data;
+
+	if (pdata == NULL) {
+		ret = -ENODEV;
+		goto free_master;
+	}
+
+	r = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	if (r == NULL) {
+		ret = -ENODEV;
+		goto free_master;
+	}
+
+	mpc83xx_spi = spi_master_get_devdata(master);
+	mpc83xx_spi->bitbang.master = spi_master_get(master);
+	mpc83xx_spi->bitbang.chipselect = mpc83xx_spi_chipselect;
+	mpc83xx_spi->bitbang.setup_transfer = mpc83xx_spi_setup_transfer;
+	mpc83xx_spi->bitbang.txrx_bufs = mpc83xx_spi_bufs;
+	mpc83xx_spi->sysclk = pdata->sysclk;
+	mpc83xx_spi->activate_cs = pdata->activate_cs;
+	mpc83xx_spi->deactivate_cs = pdata->deactivate_cs;
+	mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
+	mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
+
+	mpc83xx_spi->bitbang.master->setup = mpc83xx_spi_setup;
+	init_completion(&mpc83xx_spi->done);
+
+	mpc83xx_spi->base = ioremap(r->start, r->end - r->start + 1);
+	if (mpc83xx_spi->base == NULL) {
+		ret = -ENOMEM;
+		goto put_master;
+	}
+
+	mpc83xx_spi->irq = platform_get_irq(dev, 0);
+
+	if (mpc83xx_spi->irq < 0) {
+		ret = -ENXIO;
+		goto unmap_io;
+	}
+
+	/* Register for SPI Interrupt */
+	ret = request_irq(mpc83xx_spi->irq, mpc83xx_spi_irq,
+			  0, "mpc83xx_spi", mpc83xx_spi);
+
+	if (ret != 0)
+		goto unmap_io;
+
+	master->bus_num = pdata->bus_num;
+	master->num_chipselect = pdata->max_chipselect;
+
+	/* SPI controller initializations */
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->command, 0);
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->event, 0xffffffff);
+
+	/* Enable SPI interface */
+	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
+
+	ret = spi_bitbang_start(&mpc83xx_spi->bitbang);
+
+	if (ret != 0)
+		goto free_irq;
+
+	printk(KERN_INFO
+	       "%s: MPC83xx SPI Controller driver at 0x%p (irq = %d)\n",
+	       dev->dev.bus_id, mpc83xx_spi->base, mpc83xx_spi->irq);
+
+	return ret;
+
+free_irq:
+	free_irq(mpc83xx_spi->irq, mpc83xx_spi);
+unmap_io:
+	iounmap(mpc83xx_spi->base);
+put_master:
+	spi_master_put(master);
+free_master:
+	kfree(master);
+err:
+	return ret;
+}
+
+static int __devexit mpc83xx_spi_remove(struct platform_device *dev)
+{
+	struct mpc83xx_spi *mpc83xx_spi;
+	struct spi_master *master;
+
+	master = platform_get_drvdata(dev);
+	mpc83xx_spi = spi_master_get_devdata(master);
+
+	spi_bitbang_stop(&mpc83xx_spi->bitbang);
+	free_irq(mpc83xx_spi->irq, mpc83xx_spi);
+	iounmap(mpc83xx_spi->base);
+	spi_master_put(mpc83xx_spi->bitbang.master);
+
+	return 0;
+}
+
+static struct platform_driver mpc83xx_spi_driver = {
+	.probe = mpc83xx_spi_probe,
+	.remove = __devexit_p(mpc83xx_spi_remove),
+	.driver = {
+		   .name = "mpc83xx_spi",
+	},
+};
+
+static int __init mpc83xx_spi_init(void)
+{
+	return platform_driver_register(&mpc83xx_spi_driver);
+}
+
+static void __exit mpc83xx_spi_exit(void)
+{
+	platform_driver_unregister(&mpc83xx_spi_driver);
+}
+
+module_init(mpc83xx_spi_init);
+module_exit(mpc83xx_spi_exit);
+
+MODULE_AUTHOR("Kumar Gala");
+MODULE_DESCRIPTION("Simple MPC83xx SPI Driver");
+MODULE_LICENSE("GPL");