spi: refactor spi-coldfire-qspi to use SPI queue framework.

Use the new SPI queue framework; remove use of workqueue, replace
mcfqspi_transfer with mcfqspi_transfer_one_message, add
mcfqspi_prepare_transfer_hw and mcfqspi_unprepare_transfer_hw, update power
management routines.

Signed-off-by: Steven King <sfking@fdwdc.com>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 114 insertions, 141 deletions

diff --git a/drivers/spi/spi-coldfire-qspi.c b/drivers/spi/spi-coldfire-qspi.c
index 6eee64a5d240..b2d4b9e4e010 100644
--- a/drivers/spi/spi-coldfire-qspi.c
+++ b/drivers/spi/spi-coldfire-qspi.c
@@ -25,12 +25,12 @@
 #include <linux/errno.h>
 #include <linux/platform_device.h>
 #include <linux/sched.h>
-#include <linux/workqueue.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/spi/spi.h>
+#include <linux/pm_runtime.h>
 
 #include <asm/coldfire.h>
 #include <asm/mcfsim.h>
@@ -78,10 +78,7 @@ struct mcfqspi {
 
         wait_queue_head_t waitq;
 
-        struct work_struct work;
-        struct workqueue_struct *workq;
-        spinlock_t lock;
-        struct list_head msgq;
+        struct device *dev;
 };
 
 static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
@@ -303,120 +300,80 @@ static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
         }
 }
 
-static void mcfqspi_work(struct work_struct *work)
+static int mcfqspi_transfer_one_message(struct spi_master *master,
+                                         struct spi_message *msg)
 {
-        struct mcfqspi *mcfqspi = container_of(work, struct mcfqspi, work);
-        unsigned long flags;
-
-        spin_lock_irqsave(&mcfqspi->lock, flags);
-        while (!list_empty(&mcfqspi->msgq)) {
-                struct spi_message *msg;
-                struct spi_device *spi;
-                struct spi_transfer *xfer;
-                int status = 0;
-
-                msg = container_of(mcfqspi->msgq.next, struct spi_message,
-                                   queue);
-
-                list_del_init(&msg->queue);
-                spin_unlock_irqrestore(&mcfqspi->lock, flags);
-
-                spi = msg->spi;
-
-                list_for_each_entry(xfer, &msg->transfers, transfer_list) {
-                        bool cs_high = spi->mode & SPI_CS_HIGH;
-                        u16 qmr = MCFQSPI_QMR_MSTR;
-
-                        if (xfer->bits_per_word)
-                                qmr |= xfer->bits_per_word << 10;
-                        else
-                                qmr |= spi->bits_per_word << 10;
-                        if (spi->mode & SPI_CPHA)
-                                qmr |= MCFQSPI_QMR_CPHA;
-                        if (spi->mode & SPI_CPOL)
-                                qmr |= MCFQSPI_QMR_CPOL;
-                        if (xfer->speed_hz)
-                                qmr |= mcfqspi_qmr_baud(xfer->speed_hz);
-                        else
-                                qmr |= mcfqspi_qmr_baud(spi->max_speed_hz);
-                        mcfqspi_wr_qmr(mcfqspi, qmr);
-
-                        mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
-
-                        mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
-                        if ((xfer->bits_per_word ? xfer->bits_per_word :
-                                                spi->bits_per_word) == 8)
-                                mcfqspi_transfer_msg8(mcfqspi, xfer->len,
-                                                      xfer->tx_buf,
-                                                      xfer->rx_buf);
-                        else
-                                mcfqspi_transfer_msg16(mcfqspi, xfer->len / 2,
-                                                       xfer->tx_buf,
-                                                       xfer->rx_buf);
-                        mcfqspi_wr_qir(mcfqspi, 0);
-
-                        if (xfer->delay_usecs)
-                                udelay(xfer->delay_usecs);
-                        if (xfer->cs_change) {
-                                if (!list_is_last(&xfer->transfer_list,
-                                                  &msg->transfers))
-                                        mcfqspi_cs_deselect(mcfqspi,
-                                                            spi->chip_select,
-                                                            cs_high);
-                        } else {
-                                if (list_is_last(&xfer->transfer_list,
-                                                 &msg->transfers))
-                                        mcfqspi_cs_deselect(mcfqspi,
-                                                            spi->chip_select,
-                                                            cs_high);
-                        }
-                        msg->actual_length += xfer->len;
+        struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+        struct spi_device *spi = msg->spi;
+        struct spi_transfer *t;
+        int status = 0;
+
+        list_for_each_entry(t, &msg->transfers, transfer_list) {
+                bool cs_high = spi->mode & SPI_CS_HIGH;
+                u16 qmr = MCFQSPI_QMR_MSTR;
+
+                if (t->bits_per_word)
+                        qmr |= t->bits_per_word << 10;
+                else
+                        qmr |= spi->bits_per_word << 10;
+                if (spi->mode & SPI_CPHA)
+                        qmr |= MCFQSPI_QMR_CPHA;
+                if (spi->mode & SPI_CPOL)
+                        qmr |= MCFQSPI_QMR_CPOL;
+                if (t->speed_hz)
+                        qmr |= mcfqspi_qmr_baud(t->speed_hz);
+                else
+                        qmr |= mcfqspi_qmr_baud(spi->max_speed_hz);
+                mcfqspi_wr_qmr(mcfqspi, qmr);
+
+                mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
+
+                mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
+                if ((t->bits_per_word ? t->bits_per_word :
+                                        spi->bits_per_word) == 8)
+                        mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf,
+                                        t->rx_buf);
+                else
+                        mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf,
+                                        t->rx_buf);
+                mcfqspi_wr_qir(mcfqspi, 0);
+
+                if (t->delay_usecs)
+                        udelay(t->delay_usecs);
+                if (t->cs_change) {
+                        if (!list_is_last(&t->transfer_list, &msg->transfers))
+                                mcfqspi_cs_deselect(mcfqspi, spi->chip_select,
+                                                cs_high);
+                } else {
+                        if (list_is_last(&t->transfer_list, &msg->transfers))
+                                mcfqspi_cs_deselect(mcfqspi, spi->chip_select,
+                                                cs_high);
                 }
-                msg->status = status;
-                msg->complete(msg->context);
-
-                spin_lock_irqsave(&mcfqspi->lock, flags);
+                msg->actual_length += t->len;
         }
-        spin_unlock_irqrestore(&mcfqspi->lock, flags);
+        msg->status = status;
+        spi_finalize_current_message(master);
+
+        return status;
+
 }
 
-static int mcfqspi_transfer(struct spi_device *spi, struct spi_message *msg)
+static int mcfqspi_prepare_transfer_hw(struct spi_master *master)
 {
-        struct mcfqspi *mcfqspi;
-        struct spi_transfer *xfer;
-        unsigned long flags;
-
-        mcfqspi = spi_master_get_devdata(spi->master);
-
-        list_for_each_entry(xfer, &msg->transfers, transfer_list) {
-                if (xfer->bits_per_word && ((xfer->bits_per_word < 8)
-                                        || (xfer->bits_per_word > 16))) {
-                        dev_dbg(&spi->dev,
-                                "%d bits per word is not supported\n",
-                                xfer->bits_per_word);
-                        goto fail;
-                }
-                if (xfer->speed_hz) {
-                        u32 real_speed = MCFQSPI_BUSCLK /
-                                mcfqspi_qmr_baud(xfer->speed_hz);
-                        if (real_speed != xfer->speed_hz)
-                                dev_dbg(&spi->dev,
-                                        "using speed %d instead of %d\n",
-                                        real_speed, xfer->speed_hz);
-                }
-        }
-        msg->status = -EINPROGRESS;
-        msg->actual_length = 0;
+        struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
 
-        spin_lock_irqsave(&mcfqspi->lock, flags);
-        list_add_tail(&msg->queue, &mcfqspi->msgq);
-        queue_work(mcfqspi->workq, &mcfqspi->work);
-        spin_unlock_irqrestore(&mcfqspi->lock, flags);
+        pm_runtime_get_sync(mcfqspi->dev);
+
+        return 0;
+}
+
+static int mcfqspi_unprepare_transfer_hw(struct spi_master *master)
+{
+        struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+        pm_runtime_put_sync(mcfqspi->dev);
 
         return 0;
-fail:
-        msg->status = -EINVAL;
-        return -EINVAL;
 }
 
 static int mcfqspi_setup(struct spi_device *spi)
@@ -502,21 +459,10 @@ static int __devinit mcfqspi_probe(struct platform_device *pdev)
         }
         clk_enable(mcfqspi->clk);
 
-        mcfqspi->workq = create_singlethread_workqueue(dev_name(master->dev.parent));
-        if (!mcfqspi->workq) {
-                dev_dbg(&pdev->dev, "create_workqueue failed\n");
-                status = -ENOMEM;
-                goto fail4;
-        }
-        INIT_WORK(&mcfqspi->work, mcfqspi_work);
-        spin_lock_init(&mcfqspi->lock);
-        INIT_LIST_HEAD(&mcfqspi->msgq);
-        init_waitqueue_head(&mcfqspi->waitq);
-
         pdata = pdev->dev.platform_data;
         if (!pdata) {
                 dev_dbg(&pdev->dev, "platform data is missing\n");
-                goto fail5;
+                goto fail4;
         }
         master->bus_num = pdata->bus_num;
         master->num_chipselect = pdata->num_chipselect;
@@ -525,28 +471,33 @@ static int __devinit mcfqspi_probe(struct platform_device *pdev)
         status = mcfqspi_cs_setup(mcfqspi);
         if (status) {
                 dev_dbg(&pdev->dev, "error initializing cs_control\n");
-                goto fail5;
+                goto fail4;
         }
 
+        init_waitqueue_head(&mcfqspi->waitq);
+        mcfqspi->dev = &pdev->dev;
+
         master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
         master->setup = mcfqspi_setup;
-        master->transfer = mcfqspi_transfer;
+        master->transfer_one_message = mcfqspi_transfer_one_message;
+        master->prepare_transfer_hardware = mcfqspi_prepare_transfer_hw;
+        master->unprepare_transfer_hardware = mcfqspi_unprepare_transfer_hw;
 
         platform_set_drvdata(pdev, master);
 
         status = spi_register_master(master);
         if (status) {
                 dev_dbg(&pdev->dev, "spi_register_master failed\n");
-                goto fail6;
+                goto fail5;
         }
+        pm_runtime_enable(mcfqspi->dev);
+
         dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
 
         return 0;
 
-fail6:
-        mcfqspi_cs_teardown(mcfqspi);
 fail5:
-        destroy_workqueue(mcfqspi->workq);
+        mcfqspi_cs_teardown(mcfqspi);
 fail4:
         clk_disable(mcfqspi->clk);
         clk_put(mcfqspi->clk);
@@ -570,12 +521,12 @@ static int __devexit mcfqspi_remove(struct platform_device *pdev)
         struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 
+        pm_runtime_disable(mcfqspi->dev);
         /* disable the hardware (set the baud rate to 0) */
         mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
 
         platform_set_drvdata(pdev, NULL);
         mcfqspi_cs_teardown(mcfqspi);
-        destroy_workqueue(mcfqspi->workq);
         clk_disable(mcfqspi->clk);
         clk_put(mcfqspi->clk);
         free_irq(mcfqspi->irq, mcfqspi);
@@ -587,11 +538,13 @@ static int __devexit mcfqspi_remove(struct platform_device *pdev)
         return 0;
 }
 
-#ifdef CONFIG_PM
-
+#ifdef CONFIG_PM_SLEEP
 static int mcfqspi_suspend(struct device *dev)
 {
-        struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
+        struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
+        struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+        spi_master_suspend(master);
 
         clk_disable(mcfqspi->clk);
 
@@ -600,27 +553,47 @@ static int mcfqspi_suspend(struct device *dev)
 
 static int mcfqspi_resume(struct device *dev)
 {
-        struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
+        struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
+        struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+
+        spi_master_resume(master);
 
         clk_enable(mcfqspi->clk);
 
         return 0;
 }
+#endif
 
-static struct dev_pm_ops mcfqspi_dev_pm_ops = {
-        .suspend        = mcfqspi_suspend,
-        .resume         = mcfqspi_resume,
-};
+#ifdef CONFIG_PM_RUNTIME
+static int mcfqspi_runtime_suspend(struct device *dev)
+{
+        struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
 
-#define MCFQSPI_DEV_PM_OPS      (&mcfqspi_dev_pm_ops)
-#else
-#define MCFQSPI_DEV_PM_OPS      NULL
+        clk_disable(mcfqspi->clk);
+
+        return 0;
+}
+
+static int mcfqspi_runtime_resume(struct device *dev)
+{
+        struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
+
+        clk_enable(mcfqspi->clk);
+
+        return 0;
+}
 #endif
 
+static const struct dev_pm_ops mcfqspi_pm = {
+        SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume)
+        SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume,
+                        NULL)
+};
+
 static struct platform_driver mcfqspi_driver = {
         .driver.name    = DRIVER_NAME,
         .driver.owner   = THIS_MODULE,
-        .driver.pm      = MCFQSPI_DEV_PM_OPS,
+        .driver.pm      = &mcfqspi_pm,
         .probe          = mcfqspi_probe,
         .remove         = __devexit_p(mcfqspi_remove),
 };