diff options
Diffstat (limited to 'drivers/spi/spi-pxa2xx.c')
-rw-r--r-- | drivers/spi/spi-pxa2xx.c | 263 |
1 files changed, 44 insertions, 219 deletions
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index 5c8c4f5883c4..304cf6eb50e6 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -30,6 +30,7 @@ #include <linux/delay.h> #include <linux/gpio.h> #include <linux/slab.h> +#include <linux/clk.h> #include <asm/io.h> #include <asm/irq.h> @@ -47,7 +48,7 @@ MODULE_ALIAS("platform:pxa2xx-spi"); #define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR) #define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK) -#define IS_DMA_ALIGNED(x) ((((u32)(x)) & 0x07) == 0) +#define IS_DMA_ALIGNED(x) IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT) #define MAX_DMA_LEN 8191 #define DMA_ALIGNMENT 8 @@ -85,9 +86,6 @@ DEFINE_SSP_REG(SSPSP, 0x2c) #define DONE_STATE ((void*)2) #define ERROR_STATE ((void*)-1) -#define QUEUE_RUNNING 0 -#define QUEUE_STOPPED 1 - struct driver_data { /* Driver model hookup */ struct platform_device *pdev; @@ -117,13 +115,8 @@ struct driver_data { u32 clear_sr; u32 mask_sr; - /* Driver message queue */ - struct workqueue_struct *workqueue; - struct work_struct pump_messages; - spinlock_t lock; - struct list_head queue; - int busy; - int run; + /* Maximun clock rate */ + unsigned long max_clk_rate; /* Message Transfer pump */ struct tasklet_struct pump_transfers; @@ -173,8 +166,6 @@ struct chip_data { void (*cs_control)(u32 command); }; -static void pump_messages(struct work_struct *work); - static void cs_assert(struct driver_data *drv_data) { struct chip_data *chip = drv_data->cur_chip; @@ -444,15 +435,11 @@ static void unmap_dma_buffers(struct driver_data *drv_data) static void giveback(struct driver_data *drv_data) { struct spi_transfer* last_transfer; - unsigned long flags; struct spi_message *msg; - spin_lock_irqsave(&drv_data->lock, flags); msg = drv_data->cur_msg; drv_data->cur_msg = NULL; drv_data->cur_transfer = NULL; - queue_work(drv_data->workqueue, &drv_data->pump_messages); - spin_unlock_irqrestore(&drv_data->lock, flags); last_transfer = list_entry(msg->transfers.prev, struct spi_transfer, @@ -481,13 +468,7 @@ static void giveback(struct driver_data *drv_data) */ /* get a pointer to the next message, if any */ - spin_lock_irqsave(&drv_data->lock, flags); - if (list_empty(&drv_data->queue)) - next_msg = NULL; - else - next_msg = list_entry(drv_data->queue.next, - struct spi_message, queue); - spin_unlock_irqrestore(&drv_data->lock, flags); + next_msg = spi_get_next_queued_message(drv_data->master); /* see if the next and current messages point * to the same chip @@ -498,10 +479,7 @@ static void giveback(struct driver_data *drv_data) cs_deassert(drv_data); } - msg->state = NULL; - if (msg->complete) - msg->complete(msg->context); - + spi_finalize_current_message(drv_data->master); drv_data->cur_chip = NULL; } @@ -917,9 +895,12 @@ static int set_dma_burst_and_threshold(struct chip_data *chip, return retval; } -static unsigned int ssp_get_clk_div(struct ssp_device *ssp, int rate) +static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate) { - unsigned long ssp_clk = clk_get_rate(ssp->clk); + unsigned long ssp_clk = drv_data->max_clk_rate; + const struct ssp_device *ssp = drv_data->ssp; + + rate = min_t(int, ssp_clk, rate); if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP) return ((ssp_clk / (2 * rate) - 1) & 0xff) << 8; @@ -934,7 +915,6 @@ static void pump_transfers(unsigned long data) struct spi_transfer *transfer = NULL; struct spi_transfer *previous = NULL; struct chip_data *chip = NULL; - struct ssp_device *ssp = drv_data->ssp; void __iomem *reg = drv_data->ioaddr; u32 clk_div = 0; u8 bits = 0; @@ -1031,7 +1011,7 @@ static void pump_transfers(unsigned long data) if (transfer->bits_per_word) bits = transfer->bits_per_word; - clk_div = ssp_get_clk_div(ssp, speed); + clk_div = ssp_get_clk_div(drv_data, speed); if (bits <= 8) { drv_data->n_bytes = 1; @@ -1176,31 +1156,12 @@ static void pump_transfers(unsigned long data) write_SSCR1(cr1, reg); } -static void pump_messages(struct work_struct *work) +static int pxa2xx_spi_transfer_one_message(struct spi_master *master, + struct spi_message *msg) { - struct driver_data *drv_data = - container_of(work, struct driver_data, pump_messages); - unsigned long flags; - - /* Lock queue and check for queue work */ - spin_lock_irqsave(&drv_data->lock, flags); - if (list_empty(&drv_data->queue) || drv_data->run == QUEUE_STOPPED) { - drv_data->busy = 0; - spin_unlock_irqrestore(&drv_data->lock, flags); - return; - } - - /* Make sure we are not already running a message */ - if (drv_data->cur_msg) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return; - } - - /* Extract head of queue */ - drv_data->cur_msg = list_entry(drv_data->queue.next, - struct spi_message, queue); - list_del_init(&drv_data->cur_msg->queue); + struct driver_data *drv_data = spi_master_get_devdata(master); + drv_data->cur_msg = msg; /* Initial message state*/ drv_data->cur_msg->state = START_STATE; drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next, @@ -1213,34 +1174,6 @@ static void pump_messages(struct work_struct *work) /* Mark as busy and launch transfers */ tasklet_schedule(&drv_data->pump_transfers); - - drv_data->busy = 1; - spin_unlock_irqrestore(&drv_data->lock, flags); -} - -static int transfer(struct spi_device *spi, struct spi_message *msg) -{ - struct driver_data *drv_data = spi_master_get_devdata(spi->master); - unsigned long flags; - - spin_lock_irqsave(&drv_data->lock, flags); - - if (drv_data->run == QUEUE_STOPPED) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return -ESHUTDOWN; - } - - msg->actual_length = 0; - msg->status = -EINPROGRESS; - msg->state = START_STATE; - - list_add_tail(&msg->queue, &drv_data->queue); - - if (drv_data->run == QUEUE_RUNNING && !drv_data->busy) - queue_work(drv_data->workqueue, &drv_data->pump_messages); - - spin_unlock_irqrestore(&drv_data->lock, flags); - return 0; } @@ -1287,7 +1220,6 @@ static int setup(struct spi_device *spi) struct pxa2xx_spi_chip *chip_info = NULL; struct chip_data *chip; struct driver_data *drv_data = spi_master_get_devdata(spi->master); - struct ssp_device *ssp = drv_data->ssp; unsigned int clk_div; uint tx_thres = TX_THRESH_DFLT; uint rx_thres = RX_THRESH_DFLT; @@ -1369,7 +1301,7 @@ static int setup(struct spi_device *spi) } } - clk_div = ssp_get_clk_div(ssp, spi->max_speed_hz); + clk_div = ssp_get_clk_div(drv_data, spi->max_speed_hz); chip->speed_hz = spi->max_speed_hz; chip->cr0 = clk_div @@ -1385,12 +1317,12 @@ static int setup(struct spi_device *spi) /* NOTE: PXA25x_SSP _could_ use external clocking ... */ if (!pxa25x_ssp_comp(drv_data)) dev_dbg(&spi->dev, "%ld Hz actual, %s\n", - clk_get_rate(ssp->clk) + drv_data->max_clk_rate / (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)), chip->enable_dma ? "DMA" : "PIO"); else dev_dbg(&spi->dev, "%ld Hz actual, %s\n", - clk_get_rate(ssp->clk) / 2 + drv_data->max_clk_rate / 2 / (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)), chip->enable_dma ? "DMA" : "PIO"); @@ -1438,94 +1370,6 @@ static void cleanup(struct spi_device *spi) kfree(chip); } -static int init_queue(struct driver_data *drv_data) -{ - INIT_LIST_HEAD(&drv_data->queue); - spin_lock_init(&drv_data->lock); - - drv_data->run = QUEUE_STOPPED; - drv_data->busy = 0; - - tasklet_init(&drv_data->pump_transfers, - pump_transfers, (unsigned long)drv_data); - - INIT_WORK(&drv_data->pump_messages, pump_messages); - drv_data->workqueue = create_singlethread_workqueue( - dev_name(drv_data->master->dev.parent)); - if (drv_data->workqueue == NULL) - return -EBUSY; - - return 0; -} - -static int start_queue(struct driver_data *drv_data) -{ - unsigned long flags; - - spin_lock_irqsave(&drv_data->lock, flags); - - if (drv_data->run == QUEUE_RUNNING || drv_data->busy) { - spin_unlock_irqrestore(&drv_data->lock, flags); - return -EBUSY; - } - - drv_data->run = QUEUE_RUNNING; - drv_data->cur_msg = NULL; - drv_data->cur_transfer = NULL; - drv_data->cur_chip = NULL; - spin_unlock_irqrestore(&drv_data->lock, flags); - - queue_work(drv_data->workqueue, &drv_data->pump_messages); - - return 0; -} - -static int stop_queue(struct driver_data *drv_data) -{ - unsigned long flags; - unsigned limit = 500; - int status = 0; - - spin_lock_irqsave(&drv_data->lock, flags); - - /* This is a bit lame, but is optimized for the common execution path. - * A wait_queue on the drv_data->busy could be used, but then the common - * execution path (pump_messages) would be required to call wake_up or - * friends on every SPI message. Do this instead */ - drv_data->run = QUEUE_STOPPED; - while ((!list_empty(&drv_data->queue) || drv_data->busy) && limit--) { - spin_unlock_irqrestore(&drv_data->lock, flags); - msleep(10); - spin_lock_irqsave(&drv_data->lock, flags); - } - - if (!list_empty(&drv_data->queue) || drv_data->busy) - status = -EBUSY; - - spin_unlock_irqrestore(&drv_data->lock, flags); - - return status; -} - -static int destroy_queue(struct driver_data *drv_data) -{ - int status; - - status = stop_queue(drv_data); - /* we are unloading the module or failing to load (only two calls - * to this routine), and neither call can handle a return value. - * However, destroy_workqueue calls flush_workqueue, and that will - * block until all work is done. If the reason that stop_queue - * timed out is that the work will never finish, then it does no - * good to call destroy_workqueue, so return anyway. */ - if (status != 0) - return status; - - destroy_workqueue(drv_data->workqueue); - - return 0; -} - static int pxa2xx_spi_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -1535,11 +1379,18 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) struct ssp_device *ssp; int status; - platform_info = dev->platform_data; + platform_info = dev_get_platdata(dev); + if (!platform_info) { + dev_err(&pdev->dev, "missing platform data\n"); + return -ENODEV; + } ssp = pxa_ssp_request(pdev->id, pdev->name); - if (ssp == NULL) { - dev_err(&pdev->dev, "failed to request SSP%d\n", pdev->id); + if (!ssp) + ssp = &platform_info->ssp; + + if (!ssp->mmio_base) { + dev_err(&pdev->dev, "failed to get ssp\n"); return -ENODEV; } @@ -1561,16 +1412,15 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; - master->bus_num = pdev->id; + master->bus_num = ssp->port_id; master->num_chipselect = platform_info->num_chipselect; master->dma_alignment = DMA_ALIGNMENT; master->cleanup = cleanup; master->setup = setup; - master->transfer = transfer; + master->transfer_one_message = pxa2xx_spi_transfer_one_message; drv_data->ssp_type = ssp->type; - drv_data->null_dma_buf = (u32 *)ALIGN((u32)(drv_data + - sizeof(struct driver_data)), 8); + drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT); drv_data->ioaddr = ssp->mmio_base; drv_data->ssdr_physical = ssp->phys_base + SSDR; @@ -1625,7 +1475,9 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) } /* Enable SOC clock */ - clk_enable(ssp->clk); + clk_prepare_enable(ssp->clk); + + drv_data->max_clk_rate = clk_get_rate(ssp->clk); /* Load default SSP configuration */ write_SSCR0(0, drv_data->ioaddr); @@ -1640,33 +1492,21 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) write_SSTO(0, drv_data->ioaddr); write_SSPSP(0, drv_data->ioaddr); - /* Initial and start queue */ - status = init_queue(drv_data); - if (status != 0) { - dev_err(&pdev->dev, "problem initializing queue\n"); - goto out_error_clock_enabled; - } - status = start_queue(drv_data); - if (status != 0) { - dev_err(&pdev->dev, "problem starting queue\n"); - goto out_error_clock_enabled; - } + tasklet_init(&drv_data->pump_transfers, pump_transfers, + (unsigned long)drv_data); /* Register with the SPI framework */ platform_set_drvdata(pdev, drv_data); status = spi_register_master(master); if (status != 0) { dev_err(&pdev->dev, "problem registering spi master\n"); - goto out_error_queue_alloc; + goto out_error_clock_enabled; } return status; -out_error_queue_alloc: - destroy_queue(drv_data); - out_error_clock_enabled: - clk_disable(ssp->clk); + clk_disable_unprepare(ssp->clk); out_error_dma_alloc: if (drv_data->tx_channel != -1) @@ -1687,29 +1527,14 @@ static int pxa2xx_spi_remove(struct platform_device *pdev) { struct driver_data *drv_data = platform_get_drvdata(pdev); struct ssp_device *ssp; - int status = 0; if (!drv_data) return 0; ssp = drv_data->ssp; - /* Remove the queue */ - status = destroy_queue(drv_data); - if (status != 0) - /* the kernel does not check the return status of this - * this routine (mod->exit, within the kernel). Therefore - * nothing is gained by returning from here, the module is - * going away regardless, and we should not leave any more - * resources allocated than necessary. We cannot free the - * message memory in drv_data->queue, but we can release the - * resources below. I think the kernel should honor -EBUSY - * returns but... */ - dev_err(&pdev->dev, "pxa2xx_spi_remove: workqueue will not " - "complete, message memory not freed\n"); - /* Disable the SSP at the peripheral and SOC level */ write_SSCR0(0, drv_data->ioaddr); - clk_disable(ssp->clk); + clk_disable_unprepare(ssp->clk); /* Release DMA */ if (drv_data->master_info->enable_dma) { @@ -1749,11 +1574,11 @@ static int pxa2xx_spi_suspend(struct device *dev) struct ssp_device *ssp = drv_data->ssp; int status = 0; - status = stop_queue(drv_data); + status = spi_master_suspend(drv_data->master); if (status != 0) return status; write_SSCR0(0, drv_data->ioaddr); - clk_disable(ssp->clk); + clk_disable_unprepare(ssp->clk); return 0; } @@ -1772,10 +1597,10 @@ static int pxa2xx_spi_resume(struct device *dev) DRCMR_MAPVLD | drv_data->tx_channel; /* Enable the SSP clock */ - clk_enable(ssp->clk); + clk_prepare_enable(ssp->clk); /* Start the queue running */ - status = start_queue(drv_data); + status = spi_master_resume(drv_data->master); if (status != 0) { dev_err(dev, "problem starting queue (%d)\n", status); return status; |