diff options
author | H Hartley Sweeten <hartleys@visionengravers.com> | 2013-07-08 09:12:37 -0700 |
---|---|---|
committer | Mark Brown <broonie@linaro.org> | 2013-07-17 11:10:59 +0100 |
commit | 84ddb3c1df021c69a40af30e3e30cc7429a5d659 (patch) | |
tree | 0e4b3192f950f2519df9ac1e44e27910f02d5601 /drivers | |
parent | f7ef1da9e22ce390333645fc0ea70ff279eecd55 (diff) |
spi: spi-ep93xx: convert to the queued driver infrastructure
The SPI core provides infrastructure for standard message queueing. Use
that instead of handling it in the driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/spi/spi-ep93xx.c | 165 |
1 files changed, 19 insertions, 146 deletions
diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c index 2e64806b40af..4c9a50ce4f6c 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; @@ -230,7 +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); @@ -306,54 +284,6 @@ static int ep93xx_spi_setup(struct spi_device *spi) } /** - * 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 * @@ -801,50 +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) @@ -984,7 +893,7 @@ static int ep93xx_spi_probe(struct platform_device *pdev) 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; @@ -1002,7 +911,6 @@ static int ep93xx_spi_probe(struct platform_device *pdev) goto fail_release_master; } - spin_lock_init(&espi->lock); init_completion(&espi->wait); /* @@ -1031,23 +939,13 @@ static int ep93xx_spi_probe(struct platform_device *pdev) 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", @@ -1055,8 +953,6 @@ 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_release_master: @@ -1070,29 +966,6 @@ 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); spi_unregister_master(master); |