1 files changed, 81 insertions, 272 deletions

diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c
index cad30b8a1d71..31611f7d7be9 100644
--- a/drivers/spi/spi-ep93xx.c
+++ b/drivers/spi/spi-ep93xx.c
@@ -26,7 +26,6 @@
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
-#include <linux/workqueue.h>
 #include <linux/sched.h>
 #include <linux/scatterlist.h>
 #include <linux/spi/spi.h>
@@ -70,19 +69,13 @@
 
 /**
  * struct ep93xx_spi - EP93xx SPI controller structure
- * @lock: spinlock that protects concurrent accesses to fields @running,
- *        @current_msg and @msg_queue
  * @pdev: pointer to platform device
  * @clk: clock for the controller
  * @regs_base: pointer to ioremap()'d registers
  * @sspdr_phys: physical address of the SSPDR register
  * @min_rate: minimum clock rate (in Hz) supported by the controller
  * @max_rate: maximum clock rate (in Hz) supported by the controller
- * @running: is the queue running
- * @wq: workqueue used by the driver
- * @msg_work: work that is queued for the driver
  * @wait: wait here until given transfer is completed
- * @msg_queue: queue for the messages
  * @current_msg: message that is currently processed (or %NULL if none)
  * @tx: current byte in transfer to transmit
  * @rx: current byte in transfer to receive
@@ -96,30 +89,15 @@
  * @tx_sgt: sg table for TX transfers
  * @zeropage: dummy page used as RX buffer when only TX buffer is passed in by
  *            the client
- *
- * This structure holds EP93xx SPI controller specific information. When
- * @running is %true, driver accepts transfer requests from protocol drivers.
- * @current_msg is used to hold pointer to the message that is currently
- * processed. If @current_msg is %NULL, it means that no processing is going
- * on.
- *
- * Most of the fields are only written once and they can be accessed without
- * taking the @lock. Fields that are accessed concurrently are: @current_msg,
- * @running, and @msg_queue.
  */
 struct ep93xx_spi {
-        spinlock_t                      lock;
         const struct platform_device    *pdev;
         struct clk                      *clk;
         void __iomem                    *regs_base;
         unsigned long                   sspdr_phys;
         unsigned long                   min_rate;
         unsigned long                   max_rate;
-        bool                            running;
-        struct workqueue_struct         *wq;
-        struct work_struct              msg_work;
         struct completion               wait;
-        struct list_head                msg_queue;
         struct spi_message              *current_msg;
         size_t                          tx;
         size_t                          rx;
@@ -136,50 +114,36 @@ struct ep93xx_spi {
 /**
  * struct ep93xx_spi_chip - SPI device hardware settings
  * @spi: back pointer to the SPI device
- * @rate: max rate in hz this chip supports
- * @div_cpsr: cpsr (pre-scaler) divider
- * @div_scr: scr divider
- * @dss: bits per word (4 - 16 bits)
  * @ops: private chip operations
- *
- * This structure is used to store hardware register specific settings for each
- * SPI device. Settings are written to hardware by function
- * ep93xx_spi_chip_setup().
  */
 struct ep93xx_spi_chip {
         const struct spi_device         *spi;
-        unsigned long                   rate;
-        u8                              div_cpsr;
-        u8                              div_scr;
-        u8                              dss;
         struct ep93xx_spi_chip_ops      *ops;
 };
 
 /* converts bits per word to CR0.DSS value */
 #define bits_per_word_to_dss(bpw)       ((bpw) - 1)
 
-static inline void
-ep93xx_spi_write_u8(const struct ep93xx_spi *espi, u16 reg, u8 value)
+static void ep93xx_spi_write_u8(const struct ep93xx_spi *espi,
+                                u16 reg, u8 value)
 {
-        __raw_writeb(value, espi->regs_base + reg);
+        writeb(value, espi->regs_base + reg);
 }
 
-static inline u8
-ep93xx_spi_read_u8(const struct ep93xx_spi *spi, u16 reg)
+static u8 ep93xx_spi_read_u8(const struct ep93xx_spi *spi, u16 reg)
 {
-        return __raw_readb(spi->regs_base + reg);
+        return readb(spi->regs_base + reg);
 }
 
-static inline void
-ep93xx_spi_write_u16(const struct ep93xx_spi *espi, u16 reg, u16 value)
+static void ep93xx_spi_write_u16(const struct ep93xx_spi *espi,
+                                 u16 reg, u16 value)
 {
-        __raw_writew(value, espi->regs_base + reg);
+        writew(value, espi->regs_base + reg);
 }
 
-static inline u16
-ep93xx_spi_read_u16(const struct ep93xx_spi *spi, u16 reg)
+static u16 ep93xx_spi_read_u16(const struct ep93xx_spi *spi, u16 reg)
 {
-        return __raw_readw(spi->regs_base + reg);
+        return readw(spi->regs_base + reg);
 }
 
 static int ep93xx_spi_enable(const struct ep93xx_spi *espi)
@@ -230,17 +194,13 @@ static void ep93xx_spi_disable_interrupts(const struct ep93xx_spi *espi)
 /**
  * ep93xx_spi_calc_divisors() - calculates SPI clock divisors
  * @espi: ep93xx SPI controller struct
- * @chip: divisors are calculated for this chip
  * @rate: desired SPI output clock rate
- *
- * Function calculates cpsr (clock pre-scaler) and scr divisors based on
- * given @rate and places them to @chip->div_cpsr and @chip->div_scr. If,
- * for some reason, divisors cannot be calculated nothing is stored and
- * %-EINVAL is returned.
+ * @div_cpsr: pointer to return the cpsr (pre-scaler) divider
+ * @div_scr: pointer to return the scr divider
  */
 static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
-                                    struct ep93xx_spi_chip *chip,
-                                    unsigned long rate)
+                                    unsigned long rate,
+                                    u8 *div_cpsr, u8 *div_scr)
 {
         unsigned long spi_clk_rate = clk_get_rate(espi->clk);
         int cpsr, scr;
@@ -248,7 +208,7 @@ static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
         /*
          * Make sure that max value is between values supported by the
          * controller. Note that minimum value is already checked in
-         * ep93xx_spi_transfer().
+         * ep93xx_spi_transfer_one_message().
          */
         rate = clamp(rate, espi->min_rate, espi->max_rate);
 
@@ -263,8 +223,8 @@ static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
         for (cpsr = 2; cpsr <= 254; cpsr += 2) {
                 for (scr = 0; scr <= 255; scr++) {
                         if ((spi_clk_rate / (cpsr * (scr + 1))) <= rate) {
-                                chip->div_scr = (u8)scr;
-                                chip->div_cpsr = (u8)cpsr;
+                                *div_scr = (u8)scr;
+                                *div_cpsr = (u8)cpsr;
                                 return 0;
                         }
                 }
@@ -319,73 +279,11 @@ static int ep93xx_spi_setup(struct spi_device *spi)
                 spi_set_ctldata(spi, chip);
         }
 
-        if (spi->max_speed_hz != chip->rate) {
-                int err;
-
-                err = ep93xx_spi_calc_divisors(espi, chip, spi->max_speed_hz);
-                if (err != 0) {
-                        spi_set_ctldata(spi, NULL);
-                        kfree(chip);
-                        return err;
-                }
-                chip->rate = spi->max_speed_hz;
-        }
-
-        chip->dss = bits_per_word_to_dss(spi->bits_per_word);
-
         ep93xx_spi_cs_control(spi, false);
         return 0;
 }
 
 /**
- * ep93xx_spi_transfer() - queue message to be transferred
- * @spi: target SPI device
- * @msg: message to be transferred
- *
- * This function is called by SPI device drivers when they are going to transfer
- * a new message. It simply puts the message in the queue and schedules
- * workqueue to perform the actual transfer later on.
- *
- * Returns %0 on success and negative error in case of failure.
- */
-static int ep93xx_spi_transfer(struct spi_device *spi, struct spi_message *msg)
-{
-        struct ep93xx_spi *espi = spi_master_get_devdata(spi->master);
-        struct spi_transfer *t;
-        unsigned long flags;
-
-        if (!msg || !msg->complete)
-                return -EINVAL;
-
-        /* first validate each transfer */
-        list_for_each_entry(t, &msg->transfers, transfer_list) {
-                if (t->speed_hz && t->speed_hz < espi->min_rate)
-                                return -EINVAL;
-        }
-
-        /*
-         * Now that we own the message, let's initialize it so that it is
-         * suitable for us. We use @msg->status to signal whether there was
-         * error in transfer and @msg->state is used to hold pointer to the
-         * current transfer (or %NULL if no active current transfer).
-         */
-        msg->state = NULL;
-        msg->status = 0;
-        msg->actual_length = 0;
-
-        spin_lock_irqsave(&espi->lock, flags);
-        if (!espi->running) {
-                spin_unlock_irqrestore(&espi->lock, flags);
-                return -ESHUTDOWN;
-        }
-        list_add_tail(&msg->queue, &espi->msg_queue);
-        queue_work(espi->wq, &espi->msg_work);
-        spin_unlock_irqrestore(&espi->lock, flags);
-
-        return 0;
-}
-
-/**
  * ep93xx_spi_cleanup() - cleans up master controller specific state
  * @spi: SPI device to cleanup
  *
@@ -409,39 +307,40 @@ static void ep93xx_spi_cleanup(struct spi_device *spi)
  * ep93xx_spi_chip_setup() - configures hardware according to given @chip
  * @espi: ep93xx SPI controller struct
  * @chip: chip specific settings
- *
- * This function sets up the actual hardware registers with settings given in
- * @chip. Note that no validation is done so make sure that callers validate
- * settings before calling this.
+ * @speed_hz: transfer speed
+ * @bits_per_word: transfer bits_per_word
  */
-static void ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
-                                  const struct ep93xx_spi_chip *chip)
+static int ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
+                                 const struct ep93xx_spi_chip *chip,
+                                 u32 speed_hz, u8 bits_per_word)
 {
+        u8 dss = bits_per_word_to_dss(bits_per_word);
+        u8 div_cpsr = 0;
+        u8 div_scr = 0;
         u16 cr0;
+        int err;
 
-        cr0 = chip->div_scr << SSPCR0_SCR_SHIFT;
+        err = ep93xx_spi_calc_divisors(espi, speed_hz, &div_cpsr, &div_scr);
+        if (err)
+                return err;
+
+        cr0 = div_scr << SSPCR0_SCR_SHIFT;
         cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT;
-        cr0 |= chip->dss;
+        cr0 |= dss;
 
         dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
-                chip->spi->mode, chip->div_cpsr, chip->div_scr, chip->dss);
+                chip->spi->mode, div_cpsr, div_scr, dss);
         dev_dbg(&espi->pdev->dev, "setup: cr0 %#x", cr0);
 
-        ep93xx_spi_write_u8(espi, SSPCPSR, chip->div_cpsr);
+        ep93xx_spi_write_u8(espi, SSPCPSR, div_cpsr);
         ep93xx_spi_write_u16(espi, SSPCR0, cr0);
-}
-
-static inline int bits_per_word(const struct ep93xx_spi *espi)
-{
-        struct spi_message *msg = espi->current_msg;
-        struct spi_transfer *t = msg->state;
 
-        return t->bits_per_word;
+        return 0;
 }
 
 static void ep93xx_do_write(struct ep93xx_spi *espi, struct spi_transfer *t)
 {
-        if (bits_per_word(espi) > 8) {
+        if (t->bits_per_word > 8) {
                 u16 tx_val = 0;
 
                 if (t->tx_buf)
@@ -460,7 +359,7 @@ static void ep93xx_do_write(struct ep93xx_spi *espi, struct spi_transfer *t)
 
 static void ep93xx_do_read(struct ep93xx_spi *espi, struct spi_transfer *t)
 {
-        if (bits_per_word(espi) > 8) {
+        if (t->bits_per_word > 8) {
                 u16 rx_val;
 
                 rx_val = ep93xx_spi_read_u16(espi, SSPDR);
@@ -546,7 +445,7 @@ ep93xx_spi_dma_prepare(struct ep93xx_spi *espi, enum dma_transfer_direction dir)
         size_t len = t->len;
         int i, ret, nents;
 
-        if (bits_per_word(espi) > 8)
+        if (t->bits_per_word > 8)
                 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
         else
                 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
@@ -610,7 +509,7 @@ ep93xx_spi_dma_prepare(struct ep93xx_spi *espi, enum dma_transfer_direction dir)
         }
 
         if (WARN_ON(len)) {
-                dev_warn(&espi->pdev->dev, "len = %d expected 0!", len);
+                dev_warn(&espi->pdev->dev, "len = %zu expected 0!", len);
                 return ERR_PTR(-EINVAL);
         }
 
@@ -708,37 +607,16 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
                                         struct spi_transfer *t)
 {
         struct ep93xx_spi_chip *chip = spi_get_ctldata(msg->spi);
+        int err;
 
         msg->state = t;
 
-        /*
-         * Handle any transfer specific settings if needed. We use
-         * temporary chip settings here and restore original later when
-         * the transfer is finished.
-         */
-        if (t->speed_hz || t->bits_per_word) {
-                struct ep93xx_spi_chip tmp_chip = *chip;
-
-                if (t->speed_hz) {
-                        int err;
-
-                        err = ep93xx_spi_calc_divisors(espi, &tmp_chip,
-                                                       t->speed_hz);
-                        if (err) {
-                                dev_err(&espi->pdev->dev,
-                                        "failed to adjust speed\n");
-                                msg->status = err;
-                                return;
-                        }
-                }
-
-                if (t->bits_per_word)
-                        tmp_chip.dss = bits_per_word_to_dss(t->bits_per_word);
-
-                /*
-                 * Set up temporary new hw settings for this transfer.
-                 */
-                ep93xx_spi_chip_setup(espi, &tmp_chip);
+        err = ep93xx_spi_chip_setup(espi, chip, t->speed_hz, t->bits_per_word);
+        if (err) {
+                dev_err(&espi->pdev->dev,
+                        "failed to setup chip for transfer\n");
+                msg->status = err;
+                return;
         }
 
         espi->rx = 0;
@@ -783,9 +661,6 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
                         ep93xx_spi_cs_control(msg->spi, true);
                 }
         }
-
-        if (t->speed_hz || t->bits_per_word)
-                ep93xx_spi_chip_setup(espi, chip);
 }
 
 /*
@@ -838,10 +713,8 @@ static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
         espi->fifo_level = 0;
 
         /*
-         * Update SPI controller registers according to spi device and assert
-         * the chipselect.
+         * Assert the chipselect.
          */
-        ep93xx_spi_chip_setup(espi, spi_get_ctldata(msg->spi));
         ep93xx_spi_cs_control(msg->spi, true);
 
         list_for_each_entry(t, &msg->transfers, transfer_list) {
@@ -858,50 +731,29 @@ static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
         ep93xx_spi_disable(espi);
 }
 
-#define work_to_espi(work) (container_of((work), struct ep93xx_spi, msg_work))
-
-/**
- * ep93xx_spi_work() - EP93xx SPI workqueue worker function
- * @work: work struct
- *
- * Workqueue worker function. This function is called when there are new
- * SPI messages to be processed. Message is taken out from the queue and then
- * passed to ep93xx_spi_process_message().
- *
- * After message is transferred, protocol driver is notified by calling
- * @msg->complete(). In case of error, @msg->status is set to negative error
- * number, otherwise it contains zero (and @msg->actual_length is updated).
- */
-static void ep93xx_spi_work(struct work_struct *work)
+static int ep93xx_spi_transfer_one_message(struct spi_master *master,
+                                           struct spi_message *msg)
 {
-        struct ep93xx_spi *espi = work_to_espi(work);
-        struct spi_message *msg;
+        struct ep93xx_spi *espi = spi_master_get_devdata(master);
+        struct spi_transfer *t;
 
-        spin_lock_irq(&espi->lock);
-        if (!espi->running || espi->current_msg ||
-                list_empty(&espi->msg_queue)) {
-                spin_unlock_irq(&espi->lock);
-                return;
+        /* first validate each transfer */
+        list_for_each_entry(t, &msg->transfers, transfer_list) {
+                if (t->speed_hz < espi->min_rate)
+                        return -EINVAL;
         }
-        msg = list_first_entry(&espi->msg_queue, struct spi_message, queue);
-        list_del_init(&msg->queue);
-        espi->current_msg = msg;
-        spin_unlock_irq(&espi->lock);
 
-        ep93xx_spi_process_message(espi, msg);
+        msg->state = NULL;
+        msg->status = 0;
+        msg->actual_length = 0;
 
-        /*
-         * Update the current message and re-schedule ourselves if there are
-         * more messages in the queue.
-         */
-        spin_lock_irq(&espi->lock);
+        espi->current_msg = msg;
+        ep93xx_spi_process_message(espi, msg);
         espi->current_msg = NULL;
-        if (espi->running && !list_empty(&espi->msg_queue))
-                queue_work(espi->wq, &espi->msg_work);
-        spin_unlock_irq(&espi->lock);
 
-        /* notify the protocol driver that we are done with this message */
-        msg->complete(msg->context);
+        spi_finalize_current_message(master);
+
+        return 0;
 }
 
 static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id)
@@ -1024,14 +876,24 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
 
         info = pdev->dev.platform_data;
 
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0) {
+                dev_err(&pdev->dev, "failed to get irq resources\n");
+                return -EBUSY;
+        }
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                dev_err(&pdev->dev, "unable to get iomem resource\n");
+                return -ENODEV;
+        }
+
         master = spi_alloc_master(&pdev->dev, sizeof(*espi));
-        if (!master) {
-                dev_err(&pdev->dev, "failed to allocate spi master\n");
+        if (!master)
                 return -ENOMEM;
-        }
 
         master->setup = ep93xx_spi_setup;
-        master->transfer = ep93xx_spi_transfer;
+        master->transfer_one_message = ep93xx_spi_transfer_one_message;
         master->cleanup = ep93xx_spi_cleanup;
         master->bus_num = pdev->id;
         master->num_chipselect = info->num_chipselect;
@@ -1042,14 +904,13 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
 
         espi = spi_master_get_devdata(master);
 
-        espi->clk = clk_get(&pdev->dev, NULL);
+        espi->clk = devm_clk_get(&pdev->dev, NULL);
         if (IS_ERR(espi->clk)) {
                 dev_err(&pdev->dev, "unable to get spi clock\n");
                 error = PTR_ERR(espi->clk);
                 goto fail_release_master;
         }
 
-        spin_lock_init(&espi->lock);
         init_completion(&espi->wait);
 
         /*
@@ -1060,55 +921,31 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
         espi->min_rate = clk_get_rate(espi->clk) / (254 * 256);
         espi->pdev = pdev;
 
-        irq = platform_get_irq(pdev, 0);
-        if (irq < 0) {
-                error = -EBUSY;
-                dev_err(&pdev->dev, "failed to get irq resources\n");
-                goto fail_put_clock;
-        }
-
-        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        if (!res) {
-                dev_err(&pdev->dev, "unable to get iomem resource\n");
-                error = -ENODEV;
-                goto fail_put_clock;
-        }
-
         espi->sspdr_phys = res->start + SSPDR;
 
         espi->regs_base = devm_ioremap_resource(&pdev->dev, res);
         if (IS_ERR(espi->regs_base)) {
                 error = PTR_ERR(espi->regs_base);
-                goto fail_put_clock;
+                goto fail_release_master;
         }
 
         error = devm_request_irq(&pdev->dev, irq, ep93xx_spi_interrupt,
                                 0, "ep93xx-spi", espi);
         if (error) {
                 dev_err(&pdev->dev, "failed to request irq\n");
-                goto fail_put_clock;
+                goto fail_release_master;
         }
 
         if (info->use_dma && ep93xx_spi_setup_dma(espi))
                 dev_warn(&pdev->dev, "DMA setup failed. Falling back to PIO\n");
 
-        espi->wq = create_singlethread_workqueue("ep93xx_spid");
-        if (!espi->wq) {
-                dev_err(&pdev->dev, "unable to create workqueue\n");
-                error = -ENOMEM;
-                goto fail_free_dma;
-        }
-        INIT_WORK(&espi->msg_work, ep93xx_spi_work);
-        INIT_LIST_HEAD(&espi->msg_queue);
-        espi->running = true;
-
         /* make sure that the hardware is disabled */
         ep93xx_spi_write_u8(espi, SSPCR1, 0);
 
         error = spi_register_master(master);
         if (error) {
                 dev_err(&pdev->dev, "failed to register SPI master\n");
-                goto fail_free_queue;
+                goto fail_free_dma;
         }
 
         dev_info(&pdev->dev, "EP93xx SPI Controller at 0x%08lx irq %d\n",
@@ -1116,12 +953,8 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
 
         return 0;
 
-fail_free_queue:
-        destroy_workqueue(espi->wq);
 fail_free_dma:
         ep93xx_spi_release_dma(espi);
-fail_put_clock:
-        clk_put(espi->clk);
 fail_release_master:
         spi_master_put(master);
 
@@ -1133,31 +966,7 @@ static int ep93xx_spi_remove(struct platform_device *pdev)
         struct spi_master *master = platform_get_drvdata(pdev);
         struct ep93xx_spi *espi = spi_master_get_devdata(master);
 
-        spin_lock_irq(&espi->lock);
-        espi->running = false;
-        spin_unlock_irq(&espi->lock);
-
-        destroy_workqueue(espi->wq);
-
-        /*
-         * Complete remaining messages with %-ESHUTDOWN status.
-         */
-        spin_lock_irq(&espi->lock);
-        while (!list_empty(&espi->msg_queue)) {
-                struct spi_message *msg;
-
-                msg = list_first_entry(&espi->msg_queue,
-                                       struct spi_message, queue);
-                list_del_init(&msg->queue);
-                msg->status = -ESHUTDOWN;
-                spin_unlock_irq(&espi->lock);
-                msg->complete(msg->context);
-                spin_lock_irq(&espi->lock);
-        }
-        spin_unlock_irq(&espi->lock);
-
         ep93xx_spi_release_dma(espi);
-        clk_put(espi->clk);
 
         spi_unregister_master(master);
         return 0;