spi: dw: device tree and generic queue support

index bf98d63d92b3..cd05c0050325 100644
@@ -36,9 +36,6 @@
 #define DONE_STATE	((void *)2)
 #define ERROR_STATE	((void *)-1)
 
-#define QUEUE_RUNNING	0
-#define QUEUE_STOPPED	1
-
 #define MRST_SPI_DEASSERT	0
 #define MRST_SPI_ASSERT		1
 

@@ -263,18 +260,14 @@ static int map_dma_buffers(struct dw_spi *dws)
 static void giveback(struct dw_spi *dws)
 {
 	struct spi_transfer *last_transfer;
-	unsigned long flags;
 	struct spi_message *msg;
 
-	spin_lock_irqsave(&dws->lock, flags);
 	msg = dws->cur_msg;
 	dws->cur_msg = NULL;
 	dws->cur_transfer = NULL;
 	dws->prev_chip = dws->cur_chip;
 	dws->cur_chip = NULL;
 	dws->dma_mapped = 0;
-	queue_work(dws->workqueue, &dws->pump_messages);
-	spin_unlock_irqrestore(&dws->lock, flags);
 
 	last_transfer = list_entry(msg->transfers.prev,
 					struct spi_transfer,

@@ -283,9 +276,7 @@ static void giveback(struct dw_spi *dws)
 	if (!last_transfer->cs_change && dws->cs_control)
 		dws->cs_control(MRST_SPI_DEASSERT);
 
-	msg->state = NULL;
-	if (msg->complete)
-		msg->complete(msg->context);
+	spi_finalize_current_message(dws->master);
 }
 
 static void int_error_stop(struct dw_spi *dws, const char *msg)

@@ -536,30 +527,12 @@ early_exit:
 	return;
 }
 
-static void pump_messages(struct work_struct *work)
+static int dw_spi_transfer_one_message(struct spi_master *master,
+		struct spi_message *msg)
 {
-	struct dw_spi *dws =
-		container_of(work, struct dw_spi, pump_messages);
-	unsigned long flags;
-
-	/* Lock queue and check for queue work */
-	spin_lock_irqsave(&dws->lock, flags);
-	if (list_empty(&dws->queue) || dws->run == QUEUE_STOPPED) {
-		dws->busy = 0;
-		spin_unlock_irqrestore(&dws->lock, flags);
-		return;
-	}
-
-	/* Make sure we are not already running a message */
-	if (dws->cur_msg) {
-		spin_unlock_irqrestore(&dws->lock, flags);
-		return;
-	}
-
-	/* Extract head of queue */
-	dws->cur_msg = list_entry(dws->queue.next, struct spi_message, queue);
-	list_del_init(&dws->cur_msg->queue);
+	struct dw_spi *dws = spi_master_get_devdata(master);
 
+	dws->cur_msg = msg;
 	/* Initial message state*/
 	dws->cur_msg->state = START_STATE;
 	dws->cur_transfer = list_entry(dws->cur_msg->transfers.next,

@@ -567,46 +540,9 @@ static void pump_messages(struct work_struct *work)
 						transfer_list);
 	dws->cur_chip = spi_get_ctldata(dws->cur_msg->spi);
 
-	/* Mark as busy and launch transfers */
+	/* Launch transfers */
 	tasklet_schedule(&dws->pump_transfers);
 
-	dws->busy = 1;
-	spin_unlock_irqrestore(&dws->lock, flags);
-}
-
-/* spi_device use this to queue in their spi_msg */
-static int dw_spi_transfer(struct spi_device *spi, struct spi_message *msg)
-{
-	struct dw_spi *dws = spi_master_get_devdata(spi->master);
-	unsigned long flags;
-
-	spin_lock_irqsave(&dws->lock, flags);
-
-	if (dws->run == QUEUE_STOPPED) {
-		spin_unlock_irqrestore(&dws->lock, flags);
-		return -ESHUTDOWN;
-	}
-
-	msg->actual_length = 0;
-	msg->status = -EINPROGRESS;
-	msg->state = START_STATE;
-
-	list_add_tail(&msg->queue, &dws->queue);
-
-	if (dws->run == QUEUE_RUNNING && !dws->busy) {
-
-		if (dws->cur_transfer || dws->cur_msg)
-			queue_work(dws->workqueue,
-					&dws->pump_messages);
-		else {
-			/* If no other data transaction in air, just go */
-			spin_unlock_irqrestore(&dws->lock, flags);
-			pump_messages(&dws->pump_messages);
-			return 0;
-		}
-	}
-
-	spin_unlock_irqrestore(&dws->lock, flags);
 	return 0;
 }
 

@@ -677,81 +613,6 @@ static void dw_spi_cleanup(struct spi_device *spi)
 	kfree(chip);
 }
 
-static int init_queue(struct dw_spi *dws)
-{
-	INIT_LIST_HEAD(&dws->queue);
-	spin_lock_init(&dws->lock);
-
-	dws->run = QUEUE_STOPPED;
-	dws->busy = 0;
-
-	tasklet_init(&dws->pump_transfers,
-			pump_transfers,	(unsigned long)dws);
-
-	INIT_WORK(&dws->pump_messages, pump_messages);
-	dws->workqueue = create_singlethread_workqueue(
-					dev_name(dws->master->dev.parent));
-	if (dws->workqueue == NULL)
-		return -EBUSY;
-
-	return 0;
-}
-
-static int start_queue(struct dw_spi *dws)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&dws->lock, flags);
-
-	if (dws->run == QUEUE_RUNNING || dws->busy) {
-		spin_unlock_irqrestore(&dws->lock, flags);
-		return -EBUSY;
-	}
-
-	dws->run = QUEUE_RUNNING;
-	dws->cur_msg = NULL;
-	dws->cur_transfer = NULL;
-	dws->cur_chip = NULL;
-	dws->prev_chip = NULL;
-	spin_unlock_irqrestore(&dws->lock, flags);
-
-	queue_work(dws->workqueue, &dws->pump_messages);
-
-	return 0;
-}
-
-static int stop_queue(struct dw_spi *dws)
-{
-	unsigned long flags;
-	unsigned limit = 50;
-	int status = 0;
-
-	spin_lock_irqsave(&dws->lock, flags);
-	dws->run = QUEUE_STOPPED;
-	while ((!list_empty(&dws->queue) || dws->busy) && limit--) {
-		spin_unlock_irqrestore(&dws->lock, flags);
-		msleep(10);
-		spin_lock_irqsave(&dws->lock, flags);
-	}
-
-	if (!list_empty(&dws->queue) || dws->busy)
-		status = -EBUSY;
-	spin_unlock_irqrestore(&dws->lock, flags);
-
-	return status;
-}
-
-static int destroy_queue(struct dw_spi *dws)
-{
-	int status;
-
-	status = stop_queue(dws);
-	if (status != 0)
-		return status;
-	destroy_workqueue(dws->workqueue);
-	return 0;
-}
-
 /* Restart the controller, disable all interrupts, clean rx fifo */
 static void spi_hw_init(struct dw_spi *dws)
 {

@@ -808,7 +669,7 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
 	master->num_chipselect = dws->num_cs;
 	master->cleanup = dw_spi_cleanup;
 	master->setup = dw_spi_setup;
-	master->transfer = dw_spi_transfer;
+	master->transfer_one_message = dw_spi_transfer_one_message;
 
 	/* Basic HW init */
 	spi_hw_init(dws);

@@ -821,33 +682,21 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
 		}
 	}
 
-	/* Initial and start queue */
-	ret = init_queue(dws);
-	if (ret) {
-		dev_err(&master->dev, "problem initializing queue\n");
-		goto err_diable_hw;
-	}
-	ret = start_queue(dws);
-	if (ret) {
-		dev_err(&master->dev, "problem starting queue\n");
-		goto err_diable_hw;
-	}
+	tasklet_init(&dws->pump_transfers, pump_transfers, (unsigned long)dws);
 
 	spi_master_set_devdata(master, dws);
 	ret = devm_spi_register_master(dev, master);
 	if (ret) {
 		dev_err(&master->dev, "problem registering spi master\n");
-		goto err_queue_alloc;
+		goto err_dma_exit;
 	}
 
 	mrst_spi_debugfs_init(dws);
 	return 0;
 
-err_queue_alloc:
-	destroy_queue(dws);
+err_dma_exit:
 	if (dws->dma_ops && dws->dma_ops->dma_exit)
 		dws->dma_ops->dma_exit(dws);
-err_diable_hw:
 	spi_enable_chip(dws, 0);
 err_free_master:
 	spi_master_put(master);

@@ -857,18 +706,10 @@ EXPORT_SYMBOL_GPL(dw_spi_add_host);
 
 void dw_spi_remove_host(struct dw_spi *dws)
 {
-	int status = 0;
-
 	if (!dws)
 		return;
 	mrst_spi_debugfs_remove(dws);
 
-	/* Remove the queue */
-	status = destroy_queue(dws);
-	if (status != 0)
-		dev_err(&dws->master->dev,
-			"dw_spi_remove: workqueue will not complete, message memory not freed\n");
-
 	if (dws->dma_ops && dws->dma_ops->dma_exit)
 		dws->dma_ops->dma_exit(dws);
 	spi_enable_chip(dws, 0);

@@ -881,7 +722,7 @@ int dw_spi_suspend_host(struct dw_spi *dws)
 {
 	int ret = 0;
 
-	ret = stop_queue(dws);
+	ret = spi_master_suspend(dws->master);
 	if (ret)
 		return ret;
 	spi_enable_chip(dws, 0);

@@ -895,7 +736,7 @@ int dw_spi_resume_host(struct dw_spi *dws)
 	int ret;
 
 	spi_hw_init(dws);
-	ret = start_queue(dws);
+	ret = spi_master_resume(dws->master);
 	if (ret)
 		dev_err(&dws->master->dev, "fail to start queue (%d)\n", ret);
 	return ret;

index 587643dae11e..3fd7ab599ab4 100644
@@ -104,14 +104,6 @@ struct dw_spi {
 	u16			bus_num;
 	u16			num_cs;		/* supported slave numbers */
 
-	/* Driver message queue */
-	struct workqueue_struct	*workqueue;
-	struct work_struct	pump_messages;
-	spinlock_t		lock;
-	struct list_head	queue;
-	int			busy;
-	int			run;
-
 	/* Message Transfer pump */
 	struct tasklet_struct	pump_transfers;
 

index 1492f5ee9aaa..86d247ecd2d2 100644
@@ -16,6 +16,7 @@
 #include <linux/spi/spi.h>
 #include <linux/scatterlist.h>
 #include <linux/module.h>
+#include <linux/of.h>
 
 #include "spi-dw.h"
 

@@ -32,6 +33,7 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
 	struct dw_spi *dws;
 	struct resource *mem;
 	int ret;
+	u32 tmp;
 
 	dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
 			GFP_KERNEL);

@@ -67,7 +69,15 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
 		return ret;
 
 	dws->bus_num = pdev->id;
-	dws->num_cs = 4;
+	if (pdev->dev.of_node == NULL)
+		dws->num_cs = 4;
+	ret = of_property_read_u32(pdev->dev.of_node, "num-cs", &tmp);
+	if (ret == 0)
+		dws->num_cs = tmp;
+	if (dws->num_cs == 0) {
+		dev_err(&pdev->dev, "missing or wrong num-cs property\n");
+		goto out;
+	}
 	dws->max_freq = clk_get_rate(dwsmmio->clk);
 
 	ret = dw_spi_add_host(&pdev->dev, dws);

@@ -92,12 +102,21 @@ static int dw_spi_mmio_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_OF
+static struct of_device_id dw_spi_dt_ids[] = {
+	{ .compatible = "snps,designware-spi" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, dw_spi_dt_ids);
+#endif
+
 static struct platform_driver dw_spi_mmio_driver = {
 	.probe		= dw_spi_mmio_probe,
 	.remove		= dw_spi_mmio_remove,
 	.driver		= {
 		.name	= DRIVER_NAME,
 		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(dw_spi_dt_ids),
 	},
 };
 module_platform_driver(dw_spi_mmio_driver);

index 86d247ecd2d2..4167b6eb47d8 100644
@@ -17,6 +17,7 @@
 #include <linux/scatterlist.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_gpio.h>
 
 #include "spi-dw.h"
 

@@ -80,6 +81,27 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
 	}
 	dws->max_freq = clk_get_rate(dwsmmio->clk);
 
+	if (pdev->dev.of_node) {
+		int i;
+
+		for (i = 0; i < dws->num_cs; i++) {
+			int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
+					"cs-gpios", i);
+
+			if (cs_gpio == -EPROBE_DEFER) {
+				ret = cs_gpio;
+				goto out;
+			}
+
+			if (gpio_is_valid(cs_gpio)) {
+				ret = devm_gpio_request(&pdev->dev, cs_gpio,
+						dev_name(&pdev->dev));
+				if (ret)
+					goto out;
+			}
+		}
+	}
+
 	ret = dw_spi_add_host(&pdev->dev, dws);
 	if (ret)
 		goto out;

index cd05c0050325..2805f43ac35e 100644
@@ -24,6 +24,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/spi/spi.h>
+#include <linux/gpio.h>
 
 #include "spi-dw.h"
 

@@ -36,9 +37,6 @@
 #define DONE_STATE	((void *)2)
 #define ERROR_STATE	((void *)-1)
 
-#define MRST_SPI_DEASSERT	0
-#define MRST_SPI_ASSERT		1
-
 /* Slave spi_dev related */
 struct chip_data {
 	u16 cr0;

@@ -273,8 +271,8 @@ static void giveback(struct dw_spi *dws)
 					struct spi_transfer,
 					transfer_list);
 
-	if (!last_transfer->cs_change && dws->cs_control)
-		dws->cs_control(MRST_SPI_DEASSERT);
+	if (!last_transfer->cs_change)
+		spi_chip_sel(dws, dws->cur_msg->spi, 0);
 
 	spi_finalize_current_message(dws->master);
 }

@@ -500,7 +498,7 @@ static void pump_transfers(unsigned long data)
 			dw_writew(dws, DW_SPI_CTRL0, cr0);
 
 		spi_set_clk(dws, clk_div ? clk_div : chip->clk_div);
-		spi_chip_sel(dws, spi->chip_select);
+		spi_chip_sel(dws, spi, 1);
 
 		/* Set the interrupt mask, for poll mode just disable all int */
 		spi_mask_intr(dws, 0xff);

@@ -551,6 +549,7 @@ static int dw_spi_setup(struct spi_device *spi)
 {
 	struct dw_spi_chip *chip_info = NULL;
 	struct chip_data *chip;
+	int ret;
 
 	/* Only alloc on first setup */
 	chip = spi_get_ctldata(spi);

@@ -604,6 +603,13 @@ static int dw_spi_setup(struct spi_device *spi)
 			| (spi->mode  << SPI_MODE_OFFSET)
 			| (chip->tmode << SPI_TMOD_OFFSET);
 
+	if (gpio_is_valid(spi->cs_gpio)) {
+		ret = gpio_direction_output(spi->cs_gpio,
+				!(spi->mode & SPI_CS_HIGH));
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 

index 3fd7ab599ab4..6d2acad34f64 100644
@@ -3,6 +3,7 @@
 
 #include <linux/io.h>
 #include <linux/scatterlist.h>
+#include <linux/gpio.h>
 
 /* Register offsets */
 #define DW_SPI_CTRL0			0x00

@@ -178,15 +179,20 @@ static inline void spi_set_clk(struct dw_spi *dws, u16 div)
 	dw_writel(dws, DW_SPI_BAUDR, div);
 }
 
-static inline void spi_chip_sel(struct dw_spi *dws, u16 cs)
+static inline void spi_chip_sel(struct dw_spi *dws, struct spi_device *spi,
+		int active)
 {
-	if (cs > dws->num_cs)
-		return;
+	u16 cs = spi->chip_select;
+	int gpio_val = active ? (spi->mode & SPI_CS_HIGH) :
+		!(spi->mode & SPI_CS_HIGH);
 
 	if (dws->cs_control)
-		dws->cs_control(1);
+		dws->cs_control(active);
+	if (gpio_is_valid(spi->cs_gpio))
+		gpio_set_value(spi->cs_gpio, gpio_val);
 
-	dw_writel(dws, DW_SPI_SER, 1 << cs);
+	if (active)
+		dw_writel(dws, DW_SPI_SER, 1 << cs);
 }
 
 /* Disable IRQ bits */