diff options
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-pl022.c | 141 |
1 files changed, 85 insertions, 56 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c index 5559b22..1cff8ad 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; @@ -2231,7 +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: @@ -2305,11 +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; } |