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path: root/drivers/spi/spi-pxa2xx.c
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Diffstat (limited to 'drivers/spi/spi-pxa2xx.c')
-rw-r--r--drivers/spi/spi-pxa2xx.c263
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;