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path: root/drivers/spi/spi-pl022.c
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Diffstat (limited to 'drivers/spi/spi-pl022.c')
-rw-r--r--drivers/spi/spi-pl022.c352
1 files changed, 95 insertions, 257 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index f37ad2271ad5..400ae2121a2a 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -29,7 +29,6 @@
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/spi/spi.h>
-#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/err.h>
@@ -330,12 +329,13 @@ struct vendor_data {
* @clk: outgoing clock "SPICLK" for the SPI bus
* @master: SPI framework hookup
* @master_info: controller-specific data from machine setup
- * @workqueue: a workqueue on which any spi_message request is queued
- * @pump_messages: work struct for scheduling work to the workqueue
+ * @kworker: thread struct for message pump
+ * @kworker_task: pointer to task for message pump kworker thread
+ * @pump_messages: work struct for scheduling work to the message pump
* @queue_lock: spinlock to syncronise access to message queue
* @queue: message queue
- * @busy: workqueue is busy
- * @running: workqueue is running
+ * @busy: message pump is busy
+ * @running: message pump is running
* @pump_transfers: Tasklet used in Interrupt Transfer mode
* @cur_msg: Pointer to current spi_message being processed
* @cur_transfer: Pointer to current spi_transfer
@@ -365,14 +365,7 @@ struct pl022 {
struct clk *clk;
struct spi_master *master;
struct pl022_ssp_controller *master_info;
- /* Driver message queue */
- struct workqueue_struct *workqueue;
- struct work_struct pump_messages;
- spinlock_t queue_lock;
- struct list_head queue;
- bool busy;
- bool running;
- /* Message transfer pump */
+ /* Message per-transfer pump */
struct tasklet_struct pump_transfers;
struct spi_message *cur_msg;
struct spi_transfer *cur_transfer;
@@ -394,6 +387,7 @@ struct pl022 {
struct sg_table sgt_rx;
struct sg_table sgt_tx;
char *dummypage;
+ bool dma_running;
#endif
};
@@ -448,8 +442,6 @@ static void null_cs_control(u32 command)
static void giveback(struct pl022 *pl022)
{
struct spi_transfer *last_transfer;
- unsigned long flags;
- struct spi_message *msg;
pl022->next_msg_cs_active = false;
last_transfer = list_entry(pl022->cur_msg->transfers.prev,
@@ -477,15 +469,8 @@ static void giveback(struct pl022 *pl022)
* sent the current message could be unloaded, which
* could invalidate the cs_control() callback...
*/
-
/* get a pointer to the next message, if any */
- spin_lock_irqsave(&pl022->queue_lock, flags);
- if (list_empty(&pl022->queue))
- next_msg = NULL;
- else
- next_msg = list_entry(pl022->queue.next,
- struct spi_message, queue);
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
+ next_msg = spi_get_next_queued_message(pl022->master);
/*
* see if the next and current messages point
@@ -497,19 +482,13 @@ static void giveback(struct pl022 *pl022)
pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
else
pl022->next_msg_cs_active = true;
+
}
- spin_lock_irqsave(&pl022->queue_lock, flags);
- msg = pl022->cur_msg;
pl022->cur_msg = NULL;
pl022->cur_transfer = NULL;
pl022->cur_chip = NULL;
- queue_work(pl022->workqueue, &pl022->pump_messages);
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
-
- msg->state = NULL;
- if (msg->complete)
- msg->complete(msg->context);
+ spi_finalize_current_message(pl022->master);
}
/**
@@ -901,10 +880,12 @@ static int configure_dma(struct pl022 *pl022)
struct dma_slave_config rx_conf = {
.src_addr = SSP_DR(pl022->phybase),
.direction = DMA_DEV_TO_MEM,
+ .device_fc = false,
};
struct dma_slave_config tx_conf = {
.dst_addr = SSP_DR(pl022->phybase),
.direction = DMA_MEM_TO_DEV,
+ .device_fc = false,
};
unsigned int pages;
int ret;
@@ -1038,7 +1019,7 @@ static int configure_dma(struct pl022 *pl022)
goto err_tx_sgmap;
/* Send both scatterlists */
- rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
+ rxdesc = dmaengine_prep_slave_sg(rxchan,
pl022->sgt_rx.sgl,
rx_sglen,
DMA_DEV_TO_MEM,
@@ -1046,7 +1027,7 @@ static int configure_dma(struct pl022 *pl022)
if (!rxdesc)
goto err_rxdesc;
- txdesc = txchan->device->device_prep_slave_sg(txchan,
+ txdesc = dmaengine_prep_slave_sg(txchan,
pl022->sgt_tx.sgl,
tx_sglen,
DMA_MEM_TO_DEV,
@@ -1063,6 +1044,7 @@ static int configure_dma(struct pl022 *pl022)
dmaengine_submit(txdesc);
dma_async_issue_pending(rxchan);
dma_async_issue_pending(txchan);
+ pl022->dma_running = true;
return 0;
@@ -1141,11 +1123,12 @@ static void terminate_dma(struct pl022 *pl022)
dmaengine_terminate_all(rxchan);
dmaengine_terminate_all(txchan);
unmap_free_dma_scatter(pl022);
+ pl022->dma_running = false;
}
static void pl022_dma_remove(struct pl022 *pl022)
{
- if (pl022->busy)
+ if (pl022->dma_running)
terminate_dma(pl022);
if (pl022->dma_tx_channel)
dma_release_channel(pl022->dma_tx_channel);
@@ -1493,73 +1476,20 @@ out:
return;
}
-/**
- * pump_messages - Workqueue function which processes spi message queue
- * @data: pointer to private data of SSP driver
- *
- * This function checks if there is any spi message in the queue that
- * needs processing and delegate control to appropriate function
- * do_polling_transfer()/do_interrupt_dma_transfer()
- * based on the kind of the transfer
- *
- */
-static void pump_messages(struct work_struct *work)
+static int pl022_transfer_one_message(struct spi_master *master,
+ struct spi_message *msg)
{
- struct pl022 *pl022 =
- container_of(work, struct pl022, pump_messages);
- unsigned long flags;
- bool was_busy = false;
-
- /* Lock queue and check for queue work */
- spin_lock_irqsave(&pl022->queue_lock, flags);
- if (list_empty(&pl022->queue) || !pl022->running) {
- if (pl022->busy) {
- /* nothing more to do - disable spi/ssp and power off */
- writew((readw(SSP_CR1(pl022->virtbase)) &
- (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
-
- if (pl022->master_info->autosuspend_delay > 0) {
- pm_runtime_mark_last_busy(&pl022->adev->dev);
- pm_runtime_put_autosuspend(&pl022->adev->dev);
- } else {
- pm_runtime_put(&pl022->adev->dev);
- }
- }
- pl022->busy = false;
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
- return;
- }
-
- /* Make sure we are not already running a message */
- if (pl022->cur_msg) {
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
- return;
- }
- /* Extract head of queue */
- pl022->cur_msg =
- list_entry(pl022->queue.next, struct spi_message, queue);
-
- list_del_init(&pl022->cur_msg->queue);
- if (pl022->busy)
- was_busy = true;
- else
- pl022->busy = true;
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
+ struct pl022 *pl022 = spi_master_get_devdata(master);
/* Initial message state */
- pl022->cur_msg->state = STATE_START;
- pl022->cur_transfer = list_entry(pl022->cur_msg->transfers.next,
- struct spi_transfer, transfer_list);
+ pl022->cur_msg = msg;
+ msg->state = STATE_START;
+
+ pl022->cur_transfer = list_entry(msg->transfers.next,
+ struct spi_transfer, transfer_list);
/* Setup the SPI using the per chip configuration */
- pl022->cur_chip = spi_get_ctldata(pl022->cur_msg->spi);
- if (!was_busy)
- /*
- * We enable the core voltage and clocks here, then the clocks
- * and core will be disabled when this workqueue is run again
- * and there is no more work to be done.
- */
- pm_runtime_get_sync(&pl022->adev->dev);
+ pl022->cur_chip = spi_get_ctldata(msg->spi);
restore_state(pl022);
flush(pl022);
@@ -1568,95 +1498,37 @@ static void pump_messages(struct work_struct *work)
do_polling_transfer(pl022);
else
do_interrupt_dma_transfer(pl022);
-}
-
-static int __init init_queue(struct pl022 *pl022)
-{
- INIT_LIST_HEAD(&pl022->queue);
- spin_lock_init(&pl022->queue_lock);
-
- pl022->running = false;
- pl022->busy = false;
-
- tasklet_init(&pl022->pump_transfers, pump_transfers,
- (unsigned long)pl022);
-
- INIT_WORK(&pl022->pump_messages, pump_messages);
- pl022->workqueue = create_singlethread_workqueue(
- dev_name(pl022->master->dev.parent));
- if (pl022->workqueue == NULL)
- return -EBUSY;
return 0;
}
-static int start_queue(struct pl022 *pl022)
+static int pl022_prepare_transfer_hardware(struct spi_master *master)
{
- unsigned long flags;
-
- spin_lock_irqsave(&pl022->queue_lock, flags);
-
- if (pl022->running || pl022->busy) {
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
- return -EBUSY;
- }
-
- pl022->running = true;
- pl022->cur_msg = NULL;
- pl022->cur_transfer = NULL;
- pl022->cur_chip = NULL;
- pl022->next_msg_cs_active = false;
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
-
- queue_work(pl022->workqueue, &pl022->pump_messages);
+ struct pl022 *pl022 = spi_master_get_devdata(master);
+ /*
+ * Just make sure we have all we need to run the transfer by syncing
+ * with the runtime PM framework.
+ */
+ pm_runtime_get_sync(&pl022->adev->dev);
return 0;
}
-static int stop_queue(struct pl022 *pl022)
+static int pl022_unprepare_transfer_hardware(struct spi_master *master)
{
- unsigned long flags;
- unsigned limit = 500;
- int status = 0;
+ struct pl022 *pl022 = spi_master_get_devdata(master);
- spin_lock_irqsave(&pl022->queue_lock, flags);
+ /* nothing more to do - disable spi/ssp and power off */
+ writew((readw(SSP_CR1(pl022->virtbase)) &
+ (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
- /* This is a bit lame, but is optimized for the common execution path.
- * A wait_queue on the pl022->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 */
- while ((!list_empty(&pl022->queue) || pl022->busy) && limit--) {
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
- msleep(10);
- spin_lock_irqsave(&pl022->queue_lock, flags);
+ if (pl022->master_info->autosuspend_delay > 0) {
+ pm_runtime_mark_last_busy(&pl022->adev->dev);
+ pm_runtime_put_autosuspend(&pl022->adev->dev);
+ } else {
+ pm_runtime_put(&pl022->adev->dev);
}
- if (!list_empty(&pl022->queue) || pl022->busy)
- status = -EBUSY;
- else
- pl022->running = false;
-
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
-
- return status;
-}
-
-static int destroy_queue(struct pl022 *pl022)
-{
- int status;
-
- status = stop_queue(pl022);
- /* 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(pl022->workqueue);
-
return 0;
}
@@ -1776,38 +1648,6 @@ static int verify_controller_parameters(struct pl022 *pl022,
return 0;
}
-/**
- * pl022_transfer - transfer function registered to SPI master framework
- * @spi: spi device which is requesting transfer
- * @msg: spi message which is to handled is queued to driver queue
- *
- * This function is registered to the SPI framework for this SPI master
- * controller. It will queue the spi_message in the queue of driver if
- * the queue is not stopped and return.
- */
-static int pl022_transfer(struct spi_device *spi, struct spi_message *msg)
-{
- struct pl022 *pl022 = spi_master_get_devdata(spi->master);
- unsigned long flags;
-
- spin_lock_irqsave(&pl022->queue_lock, flags);
-
- if (!pl022->running) {
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
- return -ESHUTDOWN;
- }
- msg->actual_length = 0;
- msg->status = -EINPROGRESS;
- msg->state = STATE_START;
-
- list_add_tail(&msg->queue, &pl022->queue);
- if (pl022->running && !pl022->busy)
- queue_work(pl022->workqueue, &pl022->pump_messages);
-
- spin_unlock_irqrestore(&pl022->queue_lock, flags);
- return 0;
-}
-
static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
{
return rate / (cpsdvsr * (1 + scr));
@@ -1827,9 +1667,15 @@ static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
/* cpsdvsr = 254 & scr = 255 */
min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
- if (!((freq <= max_tclk) && (freq >= min_tclk))) {
+ if (freq > max_tclk)
+ dev_warn(&pl022->adev->dev,
+ "Max speed that can be programmed is %d Hz, you requested %d\n",
+ max_tclk, freq);
+
+ if (freq < min_tclk) {
dev_err(&pl022->adev->dev,
- "controller data is incorrect: out of range frequency");
+ "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
+ freq, min_tclk);
return -EINVAL;
}
@@ -1841,26 +1687,37 @@ static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
while (scr <= SCR_MAX) {
tmp = spi_rate(rate, cpsdvsr, scr);
- if (tmp > freq)
+ if (tmp > freq) {
+ /* we need lower freq */
scr++;
+ continue;
+ }
+
/*
- * If found exact value, update and break.
- * If found more closer value, update and continue.
+ * If found exact value, mark found and break.
+ * If found more closer value, update and break.
*/
- else if ((tmp == freq) || (tmp > best_freq)) {
+ if (tmp > best_freq) {
best_freq = tmp;
best_cpsdvsr = cpsdvsr;
best_scr = scr;
if (tmp == freq)
- break;
+ found = 1;
}
- scr++;
+ /*
+ * increased scr will give lower rates, which are not
+ * required
+ */
+ break;
}
cpsdvsr += 2;
scr = SCR_MIN;
}
+ WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
+ freq);
+
clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
clk_freq->scr = (u8) (best_scr & 0xFF);
dev_dbg(&pl022->adev->dev,
@@ -1983,9 +1840,12 @@ static int pl022_setup(struct spi_device *spi)
} else
chip->cs_control = chip_info->cs_control;
- if (bits <= 3) {
- /* PL022 doesn't support less than 4-bits */
+ /* Check bits per word with vendor specific range */
+ if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
status = -ENOTSUPP;
+ dev_err(&spi->dev, "illegal data size for this controller!\n");
+ dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
+ pl022->vendor->max_bpw);
goto err_config_params;
} else if (bits <= 8) {
dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
@@ -1998,20 +1858,10 @@ static int pl022_setup(struct spi_device *spi)
chip->read = READING_U16;
chip->write = WRITING_U16;
} else {
- if (pl022->vendor->max_bpw >= 32) {
- dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
- chip->n_bytes = 4;
- chip->read = READING_U32;
- chip->write = WRITING_U32;
- } else {
- dev_err(&spi->dev,
- "illegal data size for this controller!\n");
- dev_err(&spi->dev,
- "a standard pl022 can only handle "
- "1 <= n <= 16 bit words\n");
- status = -ENOTSUPP;
- goto err_config_params;
- }
+ dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
+ chip->n_bytes = 4;
+ chip->read = READING_U32;
+ chip->write = WRITING_U32;
}
/* Now Initialize all register settings required for this chip */
@@ -2170,7 +2020,10 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
master->num_chipselect = platform_info->num_chipselect;
master->cleanup = pl022_cleanup;
master->setup = pl022_setup;
- master->transfer = pl022_transfer;
+ master->prepare_transfer_hardware = pl022_prepare_transfer_hardware;
+ master->transfer_one_message = pl022_transfer_one_message;
+ master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
+ master->rt = platform_info->rt;
/*
* Supports mode 0-3, loopback, and active low CS. Transfers are
@@ -2214,6 +2067,10 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
goto err_no_clk_en;
}
+ /* Initialize transfer pump */
+ tasklet_init(&pl022->pump_transfers, pump_transfers,
+ (unsigned long)pl022);
+
/* Disable SSP */
writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
SSP_CR1(pl022->virtbase));
@@ -2233,17 +2090,6 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
platform_info->enable_dma = 0;
}
- /* Initialize and start queue */
- status = init_queue(pl022);
- if (status != 0) {
- dev_err(&adev->dev, "probe - problem initializing queue\n");
- goto err_init_queue;
- }
- status = start_queue(pl022);
- if (status != 0) {
- dev_err(&adev->dev, "probe - problem starting queue\n");
- goto err_start_queue;
- }
/* Register with the SPI framework */
amba_set_drvdata(adev, pl022);
status = spi_register_master(master);
@@ -2269,9 +2115,6 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
return 0;
err_spi_register:
- err_start_queue:
- err_init_queue:
- destroy_queue(pl022);
if (platform_info->enable_dma)
pl022_dma_remove(pl022);
@@ -2307,9 +2150,6 @@ pl022_remove(struct amba_device *adev)
*/
pm_runtime_get_noresume(&adev->dev);
- /* Remove the queue */
- if (destroy_queue(pl022) != 0)
- dev_err(&adev->dev, "queue remove failed\n");
load_ssp_default_config(pl022);
if (pl022->master_info->enable_dma)
pl022_dma_remove(pl022);
@@ -2331,12 +2171,12 @@ pl022_remove(struct amba_device *adev)
static int pl022_suspend(struct device *dev)
{
struct pl022 *pl022 = dev_get_drvdata(dev);
- int status = 0;
+ int ret;
- status = stop_queue(pl022);
- if (status) {
- dev_warn(dev, "suspend cannot stop queue\n");
- return status;
+ ret = spi_master_suspend(pl022->master);
+ if (ret) {
+ dev_warn(dev, "cannot suspend master\n");
+ return ret;
}
dev_dbg(dev, "suspended\n");
@@ -2346,16 +2186,16 @@ static int pl022_suspend(struct device *dev)
static int pl022_resume(struct device *dev)
{
struct pl022 *pl022 = dev_get_drvdata(dev);
- int status = 0;
+ int ret;
/* Start the queue running */
- status = start_queue(pl022);
- if (status)
- dev_err(dev, "problem starting queue (%d)\n", status);
+ ret = spi_master_resume(pl022->master);
+ if (ret)
+ dev_err(dev, "problem starting queue (%d)\n", ret);
else
dev_dbg(dev, "resumed\n");
- return status;
+ return ret;
}
#endif /* CONFIG_PM */
@@ -2365,7 +2205,6 @@ static int pl022_runtime_suspend(struct device *dev)
struct pl022 *pl022 = dev_get_drvdata(dev);
clk_disable(pl022->clk);
- amba_vcore_disable(pl022->adev);
return 0;
}
@@ -2374,7 +2213,6 @@ static int pl022_runtime_resume(struct device *dev)
{
struct pl022 *pl022 = dev_get_drvdata(dev);
- amba_vcore_enable(pl022->adev);
clk_enable(pl022->clk);
return 0;