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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.c151
1 files changed, 95 insertions, 56 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index 95400fa99d9..2f9cb43a239 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -340,6 +340,10 @@ struct vendor_data {
* @cur_msg: Pointer to current spi_message being processed
* @cur_transfer: Pointer to current spi_transfer
* @cur_chip: pointer to current clients chip(assigned from controller_state)
+ * @next_msg_cs_active: the next message in the queue has been examined
+ * and it was found that it uses the same chip select as the previous
+ * message, so we left it active after the previous transfer, and it's
+ * active already.
* @tx: current position in TX buffer to be read
* @tx_end: end position in TX buffer to be read
* @rx: current position in RX buffer to be written
@@ -373,6 +377,7 @@ struct pl022 {
struct spi_message *cur_msg;
struct spi_transfer *cur_transfer;
struct chip_data *cur_chip;
+ bool next_msg_cs_active;
void *tx;
void *tx_end;
void *rx;
@@ -445,23 +450,9 @@ static void giveback(struct pl022 *pl022)
struct spi_transfer *last_transfer;
unsigned long flags;
struct spi_message *msg;
- void (*curr_cs_control) (u32 command);
+ pl022->next_msg_cs_active = false;
- /*
- * This local reference to the chip select function
- * is needed because we set curr_chip to NULL
- * as a step toward termininating the message.
- */
- curr_cs_control = pl022->cur_chip->cs_control;
- 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);
-
- last_transfer = list_entry(msg->transfers.prev,
+ last_transfer = list_entry(pl022->cur_msg->transfers.prev,
struct spi_transfer,
transfer_list);
@@ -473,18 +464,13 @@ static void giveback(struct pl022 *pl022)
*/
udelay(last_transfer->delay_usecs);
- /*
- * Drop chip select UNLESS cs_change is true or we are returning
- * a message with an error, or next message is for another chip
- */
- if (!last_transfer->cs_change)
- curr_cs_control(SSP_CHIP_DESELECT);
- else {
+ if (!last_transfer->cs_change) {
struct spi_message *next_msg;
- /* Holding of cs was hinted, but we need to make sure
- * the next message is for the same chip. Don't waste
- * time with the following tests unless this was hinted.
+ /*
+ * cs_change was not set. We can keep the chip select
+ * enabled if there is message in the queue and it is
+ * for the same spi device.
*
* We cannot postpone this until pump_messages, because
* after calling msg->complete (below) the driver that
@@ -501,19 +487,29 @@ static void giveback(struct pl022 *pl022)
struct spi_message, queue);
spin_unlock_irqrestore(&pl022->queue_lock, flags);
- /* see if the next and current messages point
- * to the same chip
+ /*
+ * see if the next and current messages point
+ * to the same spi device.
*/
- if (next_msg && next_msg->spi != msg->spi)
+ if (next_msg && next_msg->spi != pl022->cur_msg->spi)
next_msg = NULL;
- if (!next_msg || msg->state == STATE_ERROR)
- curr_cs_control(SSP_CHIP_DESELECT);
+ if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
+ 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);
- /* This message is completed, so let's turn off the clocks & power */
- pm_runtime_put(&pl022->adev->dev);
}
/**
@@ -1244,9 +1240,9 @@ static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
flag = 1;
- /* Disable Transmit interrupt */
- writew(readw(SSP_IMSC(pl022->virtbase)) &
- (~SSP_IMSC_MASK_TXIM),
+ /* Disable Transmit interrupt, enable receive interrupt */
+ writew((readw(SSP_IMSC(pl022->virtbase)) &
+ ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
SSP_IMSC(pl022->virtbase));
}
@@ -1352,7 +1348,7 @@ static void pump_transfers(unsigned long data)
*/
udelay(previous->delay_usecs);
- /* Drop chip select only if cs_change is requested */
+ /* Reselect chip select only if cs_change was requested */
if (previous->cs_change)
pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
} else {
@@ -1379,15 +1375,22 @@ static void pump_transfers(unsigned long data)
}
err_config_dma:
- writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+ /* enable all interrupts except RX */
+ writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
}
static void do_interrupt_dma_transfer(struct pl022 *pl022)
{
- u32 irqflags = ENABLE_ALL_INTERRUPTS;
+ /*
+ * Default is to enable all interrupts except RX -
+ * this will be enabled once TX is complete
+ */
+ u32 irqflags = ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM;
+
+ /* Enable target chip, if not already active */
+ if (!pl022->next_msg_cs_active)
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
- /* Enable target chip */
- pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
/* Error path */
pl022->cur_msg->state = STATE_ERROR;
@@ -1442,7 +1445,8 @@ static void do_polling_transfer(struct pl022 *pl022)
} else {
/* STATE_START */
message->state = STATE_RUNNING;
- pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+ if (!pl022->next_msg_cs_active)
+ pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
}
/* Configuration Changing Per Transfer */
@@ -1504,14 +1508,28 @@ static void pump_messages(struct work_struct *work)
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);
@@ -1522,7 +1540,10 @@ static void pump_messages(struct work_struct *work)
list_entry(pl022->queue.next, struct spi_message, queue);
list_del_init(&pl022->cur_msg->queue);
- pl022->busy = true;
+ if (pl022->busy)
+ was_busy = true;
+ else
+ pl022->busy = true;
spin_unlock_irqrestore(&pl022->queue_lock, flags);
/* Initial message state */
@@ -1532,12 +1553,14 @@ static void pump_messages(struct work_struct *work)
/* Setup the SPI using the per chip configuration */
pl022->cur_chip = spi_get_ctldata(pl022->cur_msg->spi);
- /*
- * We enable the core voltage and clocks here, then the clocks
- * and core will be disabled when giveback() is called in each method
- * (poll/interrupt/DMA)
- */
- pm_runtime_get_sync(&pl022->adev->dev);
+ 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);
+
restore_state(pl022);
flush(pl022);
@@ -1582,6 +1605,7 @@ static int start_queue(struct pl022 *pl022)
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);
@@ -1881,7 +1905,7 @@ static int pl022_setup(struct spi_device *spi)
{
struct pl022_config_chip const *chip_info;
struct chip_data *chip;
- struct ssp_clock_params clk_freq = {0, };
+ struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
int status = 0;
struct pl022 *pl022 = spi_master_get_devdata(spi->master);
unsigned int bits = spi->bits_per_word;
@@ -2184,6 +2208,12 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
goto err_clk_prep;
}
+ status = clk_enable(pl022->clk);
+ if (status) {
+ dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
+ goto err_no_clk_en;
+ }
+
/* Disable SSP */
writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
SSP_CR1(pl022->virtbase));
@@ -2225,7 +2255,17 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
dev_dbg(dev, "probe succeeded\n");
/* let runtime pm put suspend */
- pm_runtime_put(dev);
+ if (platform_info->autosuspend_delay > 0) {
+ dev_info(&adev->dev,
+ "will use autosuspend for runtime pm, delay %dms\n",
+ platform_info->autosuspend_delay);
+ pm_runtime_set_autosuspend_delay(dev,
+ platform_info->autosuspend_delay);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_put_autosuspend(dev);
+ } else {
+ pm_runtime_put(dev);
+ }
return 0;
err_spi_register:
@@ -2237,6 +2277,8 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id)
free_irq(adev->irq[0], pl022);
err_no_irq:
+ clk_disable(pl022->clk);
+ err_no_clk_en:
clk_unprepare(pl022->clk);
err_clk_prep:
clk_put(pl022->clk);
@@ -2297,11 +2339,6 @@ static int pl022_suspend(struct device *dev)
return status;
}
- amba_vcore_enable(pl022->adev);
- amba_pclk_enable(pl022->adev);
- load_ssp_default_config(pl022);
- amba_pclk_disable(pl022->adev);
- amba_vcore_disable(pl022->adev);
dev_dbg(dev, "suspended\n");
return 0;
}
@@ -2424,6 +2461,8 @@ static struct amba_id pl022_ids[] = {
{ 0, 0 },
};
+MODULE_DEVICE_TABLE(amba, pl022_ids);
+
static struct amba_driver pl022_driver = {
.drv = {
.name = "ssp-pl022",
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 05:09:24 +0000