Message-ID: <20061107124128.0d847889@cad-250-152.norway.atmel.com>
Date:	Tue, 7 Nov 2006 12:41:28 +0100
From:	Haavard Skinnemoen <hskinnemoen@...el.com>
To:	Andrew Morton <akpm@...l.org>
Cc:	David Brownell <david-b@...bell.net>,
	Andrew Victor <andrew@...people.com>,
	Linux Kernel <linux-kernel@...r.kernel.org>
Subject: [-mm patch 4/4] Atmel SPI driver

SPI master driver for the Atmel AT32/AT91 on-chip SPI controller. This
incarnation of the driver ignores the automatic chip select logic in
the controller and controls the chip selects "manually" using gpio. It
also takes care of a few DMA-related pitfalls like misaligned buffers
or missing rx buffer by using a temporary per-device DMA buffer and
copying as necessary.

The DMA buffer code is a bit defensive in that it waits for each
transfer to run to completion before starting the next, so the
performance is a little disappointing. I want it to work on most/all
at32 and at91 controllers before optimizing this.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@...el.com>
---
 drivers/spi/Kconfig     |    7 
 drivers/spi/Makefile    |    1 
 drivers/spi/atmel_spi.c |  681 ++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/spi/atmel_spi.h |  167 +++++++++++
 4 files changed, 856 insertions(+)

Index: linux-2.6.19-rc4-mm2/drivers/spi/Kconfig
===================================================================
--- linux-2.6.19-rc4-mm2.orig/drivers/spi/Kconfig	2006-11-07 10:34:52.000000000 +0100
+++ linux-2.6.19-rc4-mm2/drivers/spi/Kconfig	2006-11-07 10:38:58.000000000 +0100
@@ -51,6 +51,13 @@ config SPI_MASTER
 comment "SPI Master Controller Drivers"
 	depends on SPI_MASTER
 
+config SPI_ATMEL
+	tristate "Atmel SPI Controller"
+	depends on (ARCH_AT91 || AVR32) && SPI_MASTER
+	help
+	  This selects a driver for the Atmel SPI Controller, present on
+	  many AT32 (AVR32) and AT91 (ARM) chips.
+
 config SPI_BITBANG
 	tristate "Bitbanging SPI master"
 	depends on SPI_MASTER && EXPERIMENTAL
Index: linux-2.6.19-rc4-mm2/drivers/spi/Makefile
===================================================================
--- linux-2.6.19-rc4-mm2.orig/drivers/spi/Makefile	2006-11-07 10:34:52.000000000 +0100
+++ linux-2.6.19-rc4-mm2/drivers/spi/Makefile	2006-11-07 10:38:58.000000000 +0100
@@ -12,6 +12,7 @@ obj-$(CONFIG_SPI_MASTER)		+= spi.o
 
 # SPI master controller drivers (bus)
 obj-$(CONFIG_SPI_BITBANG)		+= spi_bitbang.o
+obj-$(CONFIG_SPI_ATMEL)			+= atmel_spi.o
 obj-$(CONFIG_SPI_BUTTERFLY)		+= spi_butterfly.o
 obj-$(CONFIG_SPI_PXA2XX)		+= pxa2xx_spi.o
 obj-$(CONFIG_SPI_MPC83xx)		+= spi_mpc83xx.o
Index: linux-2.6.19-rc4-mm2/drivers/spi/atmel_spi.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.19-rc4-mm2/drivers/spi/atmel_spi.c	2006-11-07 11:12:12.000000000 +0100
@@ -0,0 +1,681 @@
+/*
+ * Driver for Atmel AT32 and AT91 SPI Controllers
+ *
+ * Copyright (C) 2006 Atmel Corporation
+ *
+ * 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/kernel.h>
+#include <linux/init.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+
+#include <asm/io.h>
+#include <asm/arch/board.h>
+#include <asm/arch/gpio.h>
+
+#include "atmel_spi.h"
+
+/*
+ * The core SPI transfer engine just talks to a register bank to set up
+ * DMA transfers; transfer queue progress is driven by IRQs.  The clock
+ * framework provides the base clock, subdivided for each spi_device.
+ *
+ * Newer controllers, marked with "new_1" flag, have:
+ *  - CR.LASTXFER
+ *  - SPI_MR.DIV32 may become FDIV or must-be-zero (here: always zero)
+ *  - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs)
+ *  - SPI_CSRx.CSAAT
+ *  - SPI_CSRx.SBCR allows faster clocking
+ */
+struct atmel_spi {
+	spinlock_t		lock;
+
+	void __iomem		*regs;
+	int			irq;
+	struct clk		*clk;
+	struct platform_device	*pdev;
+	unsigned		new_1:1;
+
+	u8			stopping;
+	struct list_head	queue;
+	struct spi_transfer	*current_transfer;
+	unsigned long		remaining_bytes;
+
+	void			*buffer;
+	dma_addr_t		buffer_dma;
+};
+
+#define BUFFER_SIZE		PAGE_SIZE
+#define INVALID_DMA_ADDRESS	0xffffffff
+
+/*
+ * TODO: We really want to use the same GPIO API on both architectures.
+ */
+#ifdef	CONFIG_ARM
+
+static inline int request_gpio(unsigned int pin)
+{
+	return 0;
+}
+
+static inline void free_gpio(unsigned int pin)
+{
+
+}
+
+static inline void gpio_set_value(unsigned int pin, int value)
+{
+	at91_set_gpio_value(pin, value);
+}
+
+static inline void gpio_set_output_enable(unsigned int pin, int enabled)
+{
+	at91_set_gpio_output(pin, enabled);
+}
+
+static inline void gpio_set_pullup_enable(unsigned int pin, int enabled)
+{
+
+}
+#endif
+
+/*
+ * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby
+ * they assume that spi slave device state will not change on deselect, so
+ * that automagic deselection is OK.  Not so!  Workaround uses nCSx pins
+ * as GPIOs; or newer controllers have CSAAT and friends.
+ *
+ * Since the CSAAT functionality is a bit weird on newer controllers
+ * as well, we use GPIO to control nCSx pins on all controllers.
+ */
+
+static inline void cs_activate(struct spi_device *spi)
+{
+	unsigned gpio = (unsigned) spi->controller_data;
+
+	dev_dbg(&spi->dev, "activate %u\n", gpio);
+	gpio_set_value(gpio, 0);
+}
+
+static inline void cs_deactivate(struct spi_device *spi)
+{
+	unsigned gpio = (unsigned) spi->controller_data;
+
+	dev_dbg(&spi->dev, "DEactivate %u\n", gpio);
+	gpio_set_value(gpio, 1);
+}
+
+/*
+ * Submit next transfer for DMA.
+ * lock is held, spi irq is blocked
+ */
+static void atmel_spi_next_xfer(struct spi_master *master,
+				struct spi_message *msg)
+{
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+	struct spi_transfer	*xfer;
+	u32			imr = 0;
+	u32			len;
+	dma_addr_t		tx_dma, rx_dma;
+
+	xfer = as->current_transfer;
+	if (!xfer || as->remaining_bytes == 0) {
+		if (xfer)
+			xfer = list_entry(xfer->transfer_list.next,
+					  struct spi_transfer, transfer_list);
+		else
+			xfer = list_entry(msg->transfers.next, struct spi_transfer,
+					  transfer_list);
+		as->remaining_bytes = xfer->len;
+		as->current_transfer = xfer;
+	}
+
+	len = as->remaining_bytes;
+
+	tx_dma = xfer->tx_dma;
+	rx_dma = xfer->rx_dma;
+
+	if (rx_dma == INVALID_DMA_ADDRESS) {
+		rx_dma = as->buffer_dma;
+		if (len > BUFFER_SIZE)
+			len = BUFFER_SIZE;
+	}
+	if (tx_dma == INVALID_DMA_ADDRESS) {
+		if (xfer->tx_buf) {
+			tx_dma = as->buffer_dma;
+			if (len > BUFFER_SIZE)
+				len = BUFFER_SIZE;
+			memcpy(as->buffer, xfer->tx_buf, len);
+			dma_sync_single_for_device(&as->pdev->dev,
+						   as->buffer_dma, len,
+						   DMA_TO_DEVICE);
+		} else {
+			/* Send undefined data; rx_dma is handy */
+			tx_dma = rx_dma;
+		}
+	}
+
+	spi_writel(as, RPR, rx_dma);
+	spi_writel(as, TPR, tx_dma);
+
+	as->remaining_bytes -= len;
+	if (msg->spi->bits_per_word > 8)
+		len >>= 1;
+
+	/* REVISIT: when xfer->delay_usecs == 0, the PDC "next transfer"
+	 * mechanism might help avoid the IRQ latency between transfers
+	 *
+	 * We're also waiting for ENDRX before we start the next
+	 * transfer because we need to handle some difficult timing
+	 * issues otherwise. If we wait for ENDTX in one transfer and
+	 * then starts waiting for ENDRX in the next, it's difficult
+	 * to tell the difference between the ENDRX interrupt we're
+	 * actually waiting for and the ENDRX interrupt of the
+	 * previous transfer.
+	 *
+	 * It should be doable, though. Just not now...
+	 */
+	spi_writel(as, TNCR, 0);
+	spi_writel(as, RNCR, 0);
+	imr = SPI_BIT(ENDRX);
+
+	dev_dbg(&msg->spi->dev,
+		"start xfer %p: len %u tx %p/%08x rx %p/%08x imr %08x\n",
+		xfer, xfer->len, xfer->tx_buf, xfer->tx_dma,
+		xfer->rx_buf, xfer->rx_dma, imr);
+
+	wmb();
+	spi_writel(as, TCR, len);
+	spi_writel(as, RCR, len);
+	spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN));
+	spi_writel(as, IER, imr);
+}
+
+static void atmel_spi_next_message(struct spi_master *master)
+{
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+	struct spi_message	*msg;
+	u32			mr;
+
+	BUG_ON(as->current_transfer);
+
+	msg = list_entry(as->queue.next, struct spi_message, queue);
+
+	/* Select the chip */
+	mr = spi_readl(as, MR);
+	mr = SPI_BFINS(PCS, ~(1 << msg->spi->chip_select), mr);
+	spi_writel(as, MR, mr);
+	cs_activate(msg->spi);
+
+	atmel_spi_next_xfer(master, msg);
+}
+
+static void atmel_spi_dma_map_xfer(struct atmel_spi *as,
+				   struct spi_transfer *xfer)
+{
+	xfer->tx_dma = xfer->rx_dma = INVALID_DMA_ADDRESS;
+	if (!(xfer->len & (L1_CACHE_BYTES - 1))) {
+		if (xfer->tx_buf
+		    && !((unsigned long)xfer->tx_buf & (L1_CACHE_BYTES - 1)))
+			xfer->tx_dma = dma_map_single(&as->pdev->dev,
+						      xfer->tx_buf,
+						      xfer->len,
+						      DMA_TO_DEVICE);
+		if (xfer->rx_buf
+		    && !((unsigned long)xfer->rx_buf & (L1_CACHE_BYTES - 1)))
+			xfer->rx_dma = dma_map_single(&as->pdev->dev,
+						      xfer->rx_buf,
+						      xfer->len,
+						      DMA_FROM_DEVICE);
+	}
+}
+
+static irqreturn_t
+atmel_spi_interrupt(int irq, void *dev_id)
+{
+	struct spi_master	*master = dev_id;
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+	struct spi_message	*msg;
+	struct spi_transfer	*xfer;
+	u32			status, pending, imr;
+	int			ret = IRQ_NONE;
+
+	imr = spi_readl(as, IMR);
+	status = spi_readl(as, SR);
+	pending = status & imr;
+pr_debug("spi irq: stat %05x imr %05x pend %05x\n", status, imr, pending);
+
+	if (pending & (SPI_BIT(ENDTX) | SPI_BIT(ENDRX))) {
+		ret = IRQ_HANDLED;
+
+		spi_writel(as, IDR, pending);
+		spin_lock(&as->lock);
+
+		xfer = as->current_transfer;
+		msg = list_entry(as->queue.next, struct spi_message, queue);
+
+		/*
+		 * If the rx buffer wasn't aligned, we used a bounce
+		 * buffer for the transfer. Copy the data back and
+		 * make the bounce buffer ready for re-use.
+		 */
+		if (xfer->rx_buf && xfer->rx_dma == INVALID_DMA_ADDRESS) {
+			unsigned int len = xfer->len;
+			if (len > BUFFER_SIZE)
+				len = BUFFER_SIZE;
+
+			dma_sync_single_for_cpu(&as->pdev->dev, as->buffer_dma,
+						len, DMA_FROM_DEVICE);
+			memcpy((xfer->rx_buf + xfer->len
+				- len - as->remaining_bytes),
+			       as->buffer, len);
+		}
+
+
+		if (as->remaining_bytes == 0) {
+			msg->actual_length += xfer->len;
+
+			if (!msg->is_dma_mapped) {
+				if (xfer->tx_dma != INVALID_DMA_ADDRESS)
+					dma_unmap_single(master->cdev.dev,
+							 xfer->tx_dma,
+							 xfer->len,
+							 DMA_TO_DEVICE);
+				if (xfer->rx_dma != INVALID_DMA_ADDRESS)
+					dma_unmap_single(master->cdev.dev,
+							 xfer->rx_dma,
+							 xfer->len,
+							 DMA_FROM_DEVICE);
+			}
+
+			/* REVISIT: udelay in irq is unfriendly */
+			if (xfer->delay_usecs)
+				udelay(xfer->delay_usecs);
+
+			if (msg->transfers.prev == &xfer->transfer_list) {
+
+				/* report completed message */
+				cs_deactivate(msg->spi);
+				list_del(&msg->queue);
+				msg->status = 0;
+
+				dev_dbg(master->cdev.dev,
+					"xfer complete: %u bytes transferred\n",
+					msg->actual_length);
+
+				spin_unlock(&as->lock);
+				msg->complete(msg->context);
+				spin_lock(&as->lock);
+
+				as->current_transfer = NULL;
+
+				/* continue; complete() may have queued requests */
+				if (list_empty(&as->queue) || as->stopping)
+					spi_writel(as, PTCR, SPI_BIT(RXTDIS)
+						   | SPI_BIT(TXTDIS));
+				else
+					atmel_spi_next_message(master);
+			} else {
+				if (xfer->cs_change) {
+					cs_deactivate(msg->spi);
+					udelay(1);
+					cs_activate(msg->spi);
+				}
+
+				/*
+				 * Not done yet. Submit the next transfer.
+				 *
+				 * FIXME handle protocol options for xfer
+				 */
+				atmel_spi_next_xfer(master, msg);
+			}
+		} else {
+			/*
+			 * Keep going, we still have data to send in
+			 * the current transfer.
+			 */
+			atmel_spi_next_xfer(master, msg);
+		}
+		spin_unlock(&as->lock);
+	}
+
+	return ret;
+}
+
+static int atmel_spi_setup(struct spi_device *spi)
+{
+	struct atmel_spi	*as;
+	u32			scbr, csr;
+	unsigned int		bits = spi->bits_per_word;
+	unsigned long		bus_hz, sck_hz;
+	unsigned int		npcs_pin;
+	int			ret;
+
+	as = spi_master_get_devdata(spi->master);
+
+	if (as->stopping)
+		return -ESHUTDOWN;
+
+	if (spi->chip_select > spi->master->num_chipselect) {
+		dev_dbg(&spi->dev,
+				"setup: invalid chipselect %u (%u defined)\n",
+				spi->chip_select, spi->master->num_chipselect);
+		return -EINVAL;
+	}
+
+	if (bits == 0)
+		bits = 8;
+	if (bits < 8 || bits > 16) {
+		dev_dbg(&spi->dev,
+				"setup: invalid bits_per_word %u (8 to 16)\n",
+				bits);
+		return -EINVAL;
+	}
+
+	if (spi->mode & (SPI_CS_HIGH | SPI_LSB_FIRST)) {
+		dev_dbg(&spi->dev, "setup: unsupported mode %u\n", spi->mode);
+		return -EINVAL;
+	}
+
+	/* speed zero convention is used by some upper layers */
+	bus_hz = clk_get_rate(as->clk);
+	if (spi->max_speed_hz) {
+		/* assume div32/fdiv/mbz == 0 */
+		if (!as->new_1)
+			bus_hz /= 2;
+		scbr = ((bus_hz + spi->max_speed_hz - 1)
+			/ spi->max_speed_hz);
+		if (scbr >= (1 << SPI_SCBR_SIZE)) {
+			dev_dbg(&spi->dev, "setup: %d Hz too slow, scbr %u\n",
+					spi->max_speed_hz, scbr);
+			return -EINVAL;
+		}
+	} else
+		scbr = 0xff;
+	sck_hz = bus_hz / scbr;
+
+	csr = SPI_BF(SCBR, scbr) | SPI_BF(BITS, bits - 8);
+	if (spi->mode & SPI_CPOL)
+		csr |= SPI_BIT(CPOL);
+	if (!(spi->mode & SPI_CPHA))
+		csr |= SPI_BIT(NCPHA);
+
+	/* TODO: DLYBS and DLYBCT */
+	csr |= SPI_BF(DLYBS, 10);
+	csr |= SPI_BF(DLYBCT, 10);
+
+	npcs_pin = (unsigned int)spi->controller_data;
+	if (!spi->controller_state) {
+		ret = request_gpio(npcs_pin);
+		if (ret)
+			return ret;
+		spi->controller_state = (void *)npcs_pin;
+	}
+
+	gpio_set_value(npcs_pin, 1);
+	gpio_set_output_enable(npcs_pin, 1);
+	gpio_set_pullup_enable(npcs_pin, 0);
+
+	dev_dbg(&spi->dev,
+		"setup: %lu Hz bpw %u mode 0x%x -> csr%d %08x\n",
+		sck_hz, bits, spi->mode, spi->chip_select, csr);
+
+	spi_writel(as, CSR0 + 4 * spi->chip_select, csr);
+
+	return 0;
+}
+
+static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+	struct atmel_spi	*as;
+	struct spi_transfer	*xfer;
+	unsigned long		flags;
+	struct device		*controller = spi->master->cdev.dev;
+
+	as = spi_master_get_devdata(spi->master);
+
+	dev_dbg(controller, "new message %p submitted for %s\n",
+			msg, spi->dev.bus_id);
+
+	if (unlikely(list_empty(&msg->transfers)
+			|| !spi->max_speed_hz))
+		return -EINVAL;
+
+	if (as->stopping)
+		return -ESHUTDOWN;
+
+	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+		if (!(xfer->tx_buf || xfer->rx_buf)) {
+			dev_dbg(&spi->dev, "missing rx or tx buf\n");
+			return -EINVAL;
+		}
+
+		/* FIXME implement these protocol options!! */
+		if (xfer->bits_per_word || xfer->speed_hz) {
+			dev_dbg(&spi->dev, "no protocol options yet\n");
+			return -ENOPROTOOPT;
+		}
+	}
+
+	/* scrub dcache "early" */
+	if (!msg->is_dma_mapped) {
+		list_for_each_entry(xfer, &msg->transfers, transfer_list)
+			atmel_spi_dma_map_xfer(as, xfer);
+	}
+
+	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+		dev_dbg(controller,
+			"  xfer %p: len %u tx %p/%08x rx %p/%08x\n",
+			xfer, xfer->len,
+			xfer->tx_buf, xfer->tx_dma,
+			xfer->rx_buf, xfer->rx_dma);
+	}
+
+	msg->status = -EINPROGRESS;
+	msg->actual_length = 0;
+
+	spin_lock_irqsave(&as->lock, flags);
+	list_add_tail(&msg->queue, &as->queue);
+	if (!as->current_transfer)
+		atmel_spi_next_message(spi->master);
+	spin_unlock_irqrestore(&as->lock, flags);
+
+	return 0;
+}
+
+static void atmel_spi_cleanup(const struct spi_device *spi)
+{
+	if (spi->controller_state)
+		free_gpio((unsigned int)spi->controller_data);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int __devinit atmel_spi_probe(struct platform_device *pdev)
+{
+	struct resource		*regs;
+	int			irq;
+	struct clk		*clk;
+	int			ret;
+	struct spi_master	*master;
+	struct atmel_spi	*as;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!regs)
+		return -ENXIO;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	clk = clk_get(&pdev->dev, "pclk");
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	/* setup spi core then atmel-specific driver state */
+	ret = -ENOMEM;
+	master = spi_alloc_master(&pdev->dev, sizeof *as);
+	if (!master)
+		goto out_free;
+
+	master->bus_num = pdev->id;
+	master->num_chipselect = 4;
+	master->setup = atmel_spi_setup;
+	master->transfer = atmel_spi_transfer;
+	master->cleanup = atmel_spi_cleanup;
+	platform_set_drvdata(pdev, master);
+
+	as = spi_master_get_devdata(master);
+
+	as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE,
+					&as->buffer_dma, GFP_KERNEL);
+	if (!as->buffer)
+		goto out_free;
+
+	spin_lock_init(&as->lock);
+	INIT_LIST_HEAD(&as->queue);
+	as->pdev = pdev;
+	as->regs = ioremap(regs->start, (regs->end - regs->start) + 1);
+	if (!as->regs)
+		goto out_free_buffer;
+	as->irq = irq;
+	as->clk = clk;
+#if !defined(CONFIG_ARCH_AT91RM9200)
+	/* if (!cpu_is_at91rm9200()) */
+		as->new_1 = 1;
+#endif
+
+	ret = request_irq(irq, atmel_spi_interrupt, 0,
+			pdev->dev.bus_id, master);
+	if (ret)
+		goto out_unmap_regs;
+
+	/* Initialize the hardware */
+	clk_enable(clk);
+	spi_writel(as, CR, SPI_BIT(SWRST));
+	spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
+	spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
+	spi_writel(as, CR, SPI_BIT(SPIEN));
+
+	/* go! */
+	dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n",
+			(unsigned long)regs->start, irq);
+
+	ret = spi_register_master(master);
+	if (ret)
+		goto out_reset_hw;
+
+	return 0;
+
+out_reset_hw:
+	spi_writel(as, CR, SPI_BIT(SWRST));
+	clk_disable(clk);
+	free_irq(irq, master);
+out_unmap_regs:
+	iounmap(as->regs);
+out_free_buffer:
+	dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
+			  as->buffer_dma);
+out_free:
+	clk_put(clk);
+	spi_master_put(master);
+	return ret;
+}
+
+static int __devexit atmel_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master	*master = platform_get_drvdata(pdev);
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+	struct spi_message	*msg;
+
+	/* reset the hardware and block queue progress */
+	spin_lock_irq(&as->lock);
+	as->stopping = 1;
+	spi_writel(as, CR, SPI_BIT(SWRST));
+	spi_readl(as, SR);
+	spin_unlock_irq(&as->lock);
+
+	/* Terminate remaining queued transfers */
+	list_for_each_entry(msg, &as->queue, queue) {
+		/* REVISIT unmapping the dma is sort of a NOP on ARM,
+		 * but we shouldn't depend on that...
+		 */
+		msg->status = -ESHUTDOWN;
+		msg->complete(msg->context);
+	}
+
+	dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
+			  as->buffer_dma);
+
+	clk_disable(as->clk);
+	clk_put(as->clk);
+	free_irq(as->irq, master);
+	iounmap(as->regs);
+
+	spi_unregister_master(master);
+
+	return 0;
+}
+
+#ifdef	CONFIG_PM
+
+static int atmel_spi_suspend(struct platform_device *pdev, pm_message_t mesg)
+{
+	struct spi_master	*master = platform_get_drvdata(pdev);
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+
+	clk_disable(as->clk);
+	return 0;
+}
+
+static int atmel_spi_resume(struct platform_device *pdev)
+{
+	struct spi_master	*master = platform_get_drvdata(pdev);
+	struct atmel_spi	*as = spi_master_get_devdata(master);
+
+	clk_enable(as->clk);
+	return 0;
+}
+
+#else
+#define	atmel_spi_suspend	NULL
+#define	atmel_spi_resume	NULL
+#endif
+
+
+static struct platform_driver atmel_spi_driver = {
+	.driver		= {
+		.name	= "atmel_spi",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= atmel_spi_probe,
+	.suspend	= atmel_spi_suspend,
+	.resume		= atmel_spi_resume,
+	.remove		= __devexit_p(atmel_spi_remove),
+};
+
+static int __init atmel_spi_init(void)
+{
+	return platform_driver_register(&atmel_spi_driver);
+}
+module_init(atmel_spi_init);
+
+static void __exit atmel_spi_exit(void)
+{
+	platform_driver_unregister(&atmel_spi_driver);
+}
+module_exit(atmel_spi_exit);
+
+MODULE_DESCRIPTION("Atmel AT32/AT91 SPI Controller driver");
+MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@...el.com>");
+MODULE_LICENSE("GPL");
Index: linux-2.6.19-rc4-mm2/drivers/spi/atmel_spi.h
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.19-rc4-mm2/drivers/spi/atmel_spi.h	2006-11-07 10:38:58.000000000 +0100
@@ -0,0 +1,167 @@
+/*
+ * Register definitions for Atmel Serial Peripheral Interface (SPI)
+ *
+ * Copyright (C) 2006 Atmel Corporation
+ *
+ * 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.
+ */
+#ifndef __ATMEL_SPI_H__
+#define __ATMEL_SPI_H__
+
+/* SPI register offsets */
+#define SPI_CR					0x0000
+#define SPI_MR					0x0004
+#define SPI_RDR					0x0008
+#define SPI_TDR					0x000c
+#define SPI_SR					0x0010
+#define SPI_IER					0x0014
+#define SPI_IDR					0x0018
+#define SPI_IMR					0x001c
+#define SPI_CSR0				0x0030
+#define SPI_CSR1				0x0034
+#define SPI_CSR2				0x0038
+#define SPI_CSR3				0x003c
+#define SPI_RPR					0x0100
+#define SPI_RCR					0x0104
+#define SPI_TPR					0x0108
+#define SPI_TCR					0x010c
+#define SPI_RNPR				0x0110
+#define SPI_RNCR				0x0114
+#define SPI_TNPR				0x0118
+#define SPI_TNCR				0x011c
+#define SPI_PTCR				0x0120
+#define SPI_PTSR				0x0124
+
+/* Bitfields in CR */
+#define SPI_SPIEN_OFFSET			0
+#define SPI_SPIEN_SIZE				1
+#define SPI_SPIDIS_OFFSET			1
+#define SPI_SPIDIS_SIZE				1
+#define SPI_SWRST_OFFSET			7
+#define SPI_SWRST_SIZE				1
+#define SPI_LASTXFER_OFFSET			24
+#define SPI_LASTXFER_SIZE			1
+
+/* Bitfields in MR */
+#define SPI_MSTR_OFFSET				0
+#define SPI_MSTR_SIZE				1
+#define SPI_PS_OFFSET				1
+#define SPI_PS_SIZE				1
+#define SPI_PCSDEC_OFFSET			2
+#define SPI_PCSDEC_SIZE				1
+#define SPI_FDIV_OFFSET				3
+#define SPI_FDIV_SIZE				1
+#define SPI_MODFDIS_OFFSET			4
+#define SPI_MODFDIS_SIZE			1
+#define SPI_LLB_OFFSET				7
+#define SPI_LLB_SIZE				1
+#define SPI_PCS_OFFSET				16
+#define SPI_PCS_SIZE				4
+#define SPI_DLYBCS_OFFSET			24
+#define SPI_DLYBCS_SIZE				8
+
+/* Bitfields in RDR */
+#define SPI_RD_OFFSET				0
+#define SPI_RD_SIZE				16
+
+/* Bitfields in TDR */
+#define SPI_TD_OFFSET				0
+#define SPI_TD_SIZE				16
+
+/* Bitfields in SR */
+#define SPI_RDRF_OFFSET				0
+#define SPI_RDRF_SIZE				1
+#define SPI_TDRE_OFFSET				1
+#define SPI_TDRE_SIZE				1
+#define SPI_MODF_OFFSET				2
+#define SPI_MODF_SIZE				1
+#define SPI_OVRES_OFFSET			3
+#define SPI_OVRES_SIZE				1
+#define SPI_ENDRX_OFFSET			4
+#define SPI_ENDRX_SIZE				1
+#define SPI_ENDTX_OFFSET			5
+#define SPI_ENDTX_SIZE				1
+#define SPI_RXBUFF_OFFSET			6
+#define SPI_RXBUFF_SIZE				1
+#define SPI_TXBUFE_OFFSET			7
+#define SPI_TXBUFE_SIZE				1
+#define SPI_NSSR_OFFSET				8
+#define SPI_NSSR_SIZE				1
+#define SPI_TXEMPTY_OFFSET			9
+#define SPI_TXEMPTY_SIZE			1
+#define SPI_SPIENS_OFFSET			16
+#define SPI_SPIENS_SIZE				1
+
+/* Bitfields in CSR0 */
+#define SPI_CPOL_OFFSET				0
+#define SPI_CPOL_SIZE				1
+#define SPI_NCPHA_OFFSET			1
+#define SPI_NCPHA_SIZE				1
+#define SPI_CSAAT_OFFSET			3
+#define SPI_CSAAT_SIZE				1
+#define SPI_BITS_OFFSET				4
+#define SPI_BITS_SIZE				4
+#define SPI_SCBR_OFFSET				8
+#define SPI_SCBR_SIZE				8
+#define SPI_DLYBS_OFFSET			16
+#define SPI_DLYBS_SIZE				8
+#define SPI_DLYBCT_OFFSET			24
+#define SPI_DLYBCT_SIZE				8
+
+/* Bitfields in RCR */
+#define SPI_RXCTR_OFFSET			0
+#define SPI_RXCTR_SIZE				16
+
+/* Bitfields in TCR */
+#define SPI_TXCTR_OFFSET			0
+#define SPI_TXCTR_SIZE				16
+
+/* Bitfields in RNCR */
+#define SPI_RXNCR_OFFSET			0
+#define SPI_RXNCR_SIZE				16
+
+/* Bitfields in TNCR */
+#define SPI_TXNCR_OFFSET			0
+#define SPI_TXNCR_SIZE				16
+
+/* Bitfields in PTCR */
+#define SPI_RXTEN_OFFSET			0
+#define SPI_RXTEN_SIZE				1
+#define SPI_RXTDIS_OFFSET			1
+#define SPI_RXTDIS_SIZE				1
+#define SPI_TXTEN_OFFSET			8
+#define SPI_TXTEN_SIZE				1
+#define SPI_TXTDIS_OFFSET			9
+#define SPI_TXTDIS_SIZE				1
+
+/* Constants for BITS */
+#define SPI_BITS_8_BPT				0
+#define SPI_BITS_9_BPT				1
+#define SPI_BITS_10_BPT				2
+#define SPI_BITS_11_BPT				3
+#define SPI_BITS_12_BPT				4
+#define SPI_BITS_13_BPT				5
+#define SPI_BITS_14_BPT				6
+#define SPI_BITS_15_BPT				7
+#define SPI_BITS_16_BPT				8
+
+/* Bit manipulation macros */
+#define SPI_BIT(name) \
+	(1 << SPI_##name##_OFFSET)
+#define SPI_BF(name,value) \
+	(((value) & ((1 << SPI_##name##_SIZE) - 1)) << SPI_##name##_OFFSET)
+#define SPI_BFEXT(name,value) \
+	(((value) >> SPI_##name##_OFFSET) & ((1 << SPI_##name##_SIZE) - 1))
+#define SPI_BFINS(name,value,old) \
+	( ((old) & ~(((1 << SPI_##name##_SIZE) - 1) << SPI_##name##_OFFSET)) \
+	  | SPI_BF(name,value))
+
+/* Register access macros */
+#define spi_readl(port,reg) \
+	readl((port)->regs + SPI_##reg)
+#define spi_writel(port,reg,value) \
+	writel((value), (port)->regs + SPI_##reg)
+
+#endif /* __ATMEL_SPI_H__ */
-
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