From 9d5354145104cf392568a948c5ce2cb97f373fd7 Mon Sep 17 00:00:00 2001 From: Alain Volmat Date: Wed, 7 Jul 2021 10:27:01 +0200 Subject: spi: stm32: enable pm_runtime autosuspend This commit enables the pm_runtime autosuspend and sets a 1ms autosuspend delay. Signed-off-by: Alain Volmat Link: https://lore.kernel.org/r/1625646426-5826-3-git-send-email-alain.volmat@foss.st.com Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 05618a618939..4dbd5cbe0c11 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -162,6 +162,8 @@ #define SPI_3WIRE_TX 3 #define SPI_3WIRE_RX 4 +#define STM32_SPI_AUTOSUSPEND_DELAY 1 /* 1 ms */ + /* * use PIO for small transfers, avoiding DMA setup/teardown overhead for drivers * without fifo buffers. @@ -1927,6 +1929,9 @@ static int stm32_spi_probe(struct platform_device *pdev) if (spi->dma_tx || spi->dma_rx) master->can_dma = stm32_spi_can_dma; + pm_runtime_set_autosuspend_delay(&pdev->dev, + STM32_SPI_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_active(&pdev->dev); pm_runtime_get_noresume(&pdev->dev); pm_runtime_enable(&pdev->dev); @@ -1938,6 +1943,9 @@ static int stm32_spi_probe(struct platform_device *pdev) goto err_pm_disable; } + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + dev_info(&pdev->dev, "driver initialized\n"); return 0; @@ -1946,6 +1954,7 @@ err_pm_disable: pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); err_dma_release: if (spi->dma_tx) dma_release_channel(spi->dma_tx); @@ -1970,6 +1979,8 @@ static int stm32_spi_remove(struct platform_device *pdev) pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); + if (master->dma_tx) dma_release_channel(master->dma_tx); if (master->dma_rx) -- cgit v1.2.3 From 70526e0b7601792bf546044fff92c368112f1d3f Mon Sep 17 00:00:00 2001 From: Alain Volmat Date: Wed, 7 Jul 2021 10:27:03 +0200 Subject: spi: stm32: Revert "properly handle 0 byte transfer" 0 byte transfer handling is now done within the core in code added by commit b306320322c9 ("spi: Skip zero-length transfers in spi_transfer_one_message()") This reverts commit 2269f5a8b1a7 ("spi: stm32: properly handle 0 byte transfer") Signed-off-by: Alain Volmat Link: https://lore.kernel.org/r/1625646426-5826-5-git-send-email-alain.volmat@foss.st.com Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 4dbd5cbe0c11..d37bfead4d8c 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -1647,10 +1647,6 @@ static int stm32_spi_transfer_one(struct spi_master *master, struct stm32_spi *spi = spi_master_get_devdata(master); int ret; - /* Don't do anything on 0 bytes transfers */ - if (transfer->len == 0) - return 0; - spi->tx_buf = transfer->tx_buf; spi->rx_buf = transfer->rx_buf; spi->tx_len = spi->tx_buf ? transfer->len : 0; -- cgit v1.2.3 From d87a5d64b5037cfedd7eb47d785b5c159ace8d9b Mon Sep 17 00:00:00 2001 From: Amelie Delaunay Date: Wed, 7 Jul 2021 10:27:04 +0200 Subject: spi: stm32h7: rework rx fifo read function Remove flush parameter and check RXWNE or RXPLVL when end of transfer flag is set. Signed-off-by: Amelie Delaunay Signed-off-by: Alain Volmat Link: https://lore.kernel.org/r/1625646426-5826-6-git-send-email-alain.volmat@foss.st.com Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index d37bfead4d8c..c2144e3c57eb 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -570,29 +570,30 @@ static void stm32f4_spi_read_rx(struct stm32_spi *spi) /** * stm32h7_spi_read_rxfifo - Read bytes in Receive Data Register * @spi: pointer to the spi controller data structure - * @flush: boolean indicating that FIFO should be flushed * * Write in rx_buf depends on remaining bytes to avoid to write beyond * rx_buf end. */ -static void stm32h7_spi_read_rxfifo(struct stm32_spi *spi, bool flush) +static void stm32h7_spi_read_rxfifo(struct stm32_spi *spi) { u32 sr = readl_relaxed(spi->base + STM32H7_SPI_SR); u32 rxplvl = FIELD_GET(STM32H7_SPI_SR_RXPLVL, sr); while ((spi->rx_len > 0) && ((sr & STM32H7_SPI_SR_RXP) || - (flush && ((sr & STM32H7_SPI_SR_RXWNE) || (rxplvl > 0))))) { + ((sr & STM32H7_SPI_SR_EOT) && + ((sr & STM32H7_SPI_SR_RXWNE) || (rxplvl > 0))))) { u32 offs = spi->cur_xferlen - spi->rx_len; if ((spi->rx_len >= sizeof(u32)) || - (flush && (sr & STM32H7_SPI_SR_RXWNE))) { + (sr & STM32H7_SPI_SR_RXWNE)) { u32 *rx_buf32 = (u32 *)(spi->rx_buf + offs); *rx_buf32 = readl_relaxed(spi->base + STM32H7_SPI_RXDR); spi->rx_len -= sizeof(u32); } else if ((spi->rx_len >= sizeof(u16)) || - (flush && (rxplvl >= 2 || spi->cur_bpw > 8))) { + (!(sr & STM32H7_SPI_SR_RXWNE) && + (rxplvl >= 2 || spi->cur_bpw > 8))) { u16 *rx_buf16 = (u16 *)(spi->rx_buf + offs); *rx_buf16 = readw_relaxed(spi->base + STM32H7_SPI_RXDR); @@ -608,8 +609,8 @@ static void stm32h7_spi_read_rxfifo(struct stm32_spi *spi, bool flush) rxplvl = FIELD_GET(STM32H7_SPI_SR_RXPLVL, sr); } - dev_dbg(spi->dev, "%s%s: %d bytes left\n", __func__, - flush ? "(flush)" : "", spi->rx_len); + dev_dbg(spi->dev, "%s: %d bytes left (sr=%08x)\n", + __func__, spi->rx_len, sr); } /** @@ -677,12 +678,7 @@ static void stm32f4_spi_disable(struct stm32_spi *spi) * @spi: pointer to the spi controller data structure * * RX-Fifo is flushed when SPI controller is disabled. To prevent any data - * loss, use stm32h7_spi_read_rxfifo(flush) to read the remaining bytes in - * RX-Fifo. - * Normally, if TSIZE has been configured, we should relax the hardware at the - * reception of the EOT interrupt. But in case of error, EOT will not be - * raised. So the subsystem unprepare_message call allows us to properly - * complete the transfer from an hardware point of view. + * loss, use stm32_spi_read_rxfifo to read the remaining bytes in RX-Fifo. */ static void stm32h7_spi_disable(struct stm32_spi *spi) { @@ -717,7 +713,7 @@ static void stm32h7_spi_disable(struct stm32_spi *spi) } if (!spi->cur_usedma && spi->rx_buf && (spi->rx_len > 0)) - stm32h7_spi_read_rxfifo(spi, true); + stm32h7_spi_read_rxfifo(spi); if (spi->cur_usedma && spi->dma_tx) dmaengine_terminate_all(spi->dma_tx); @@ -913,7 +909,7 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id) if (__ratelimit(&rs)) dev_dbg_ratelimited(spi->dev, "Communication suspended\n"); if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0))) - stm32h7_spi_read_rxfifo(spi, false); + stm32h7_spi_read_rxfifo(spi); /* * If communication is suspended while using DMA, it means * that something went wrong, so stop the current transfer @@ -934,7 +930,7 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id) if (sr & STM32H7_SPI_SR_EOT) { if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0))) - stm32h7_spi_read_rxfifo(spi, true); + stm32h7_spi_read_rxfifo(spi); end = true; } @@ -944,7 +940,7 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id) if (sr & STM32H7_SPI_SR_RXP) if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0))) - stm32h7_spi_read_rxfifo(spi, false); + stm32h7_spi_read_rxfifo(spi); writel_relaxed(sr & mask, spi->base + STM32H7_SPI_IFCR); -- cgit v1.2.3 From dc6620c31326bc50fa22fd8900a9f995d0a04bc1 Mon Sep 17 00:00:00 2001 From: Alain Volmat Date: Wed, 7 Jul 2021 10:27:05 +0200 Subject: spi: stm32h7: don't wait for EOT and flush fifo on disable In nominal cases, disable is called as part of the unprepare_message, after receiving a EOT and after receiving all data so it doesn't make sense to check for EOT and empty the FIFO. Moreover, at the end of the disable, the SPI is disable (SPE) leading to clear of all internal FIFO, leaving the IP in a known status. Signed-off-by: Alain Volmat Link: https://lore.kernel.org/r/1625646426-5826-7-git-send-email-alain.volmat@foss.st.com Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 24 ++---------------------- 1 file changed, 2 insertions(+), 22 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index c2144e3c57eb..535f4bebc010 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -677,13 +677,12 @@ static void stm32f4_spi_disable(struct stm32_spi *spi) * stm32h7_spi_disable - Disable SPI controller * @spi: pointer to the spi controller data structure * - * RX-Fifo is flushed when SPI controller is disabled. To prevent any data - * loss, use stm32_spi_read_rxfifo to read the remaining bytes in RX-Fifo. + * RX-Fifo is flushed when SPI controller is disabled. */ static void stm32h7_spi_disable(struct stm32_spi *spi) { unsigned long flags; - u32 cr1, sr; + u32 cr1; dev_dbg(spi->dev, "disable controller\n"); @@ -696,25 +695,6 @@ static void stm32h7_spi_disable(struct stm32_spi *spi) return; } - /* Wait on EOT or suspend the flow */ - if (readl_relaxed_poll_timeout_atomic(spi->base + STM32H7_SPI_SR, - sr, !(sr & STM32H7_SPI_SR_EOT), - 10, 100000) < 0) { - if (cr1 & STM32H7_SPI_CR1_CSTART) { - writel_relaxed(cr1 | STM32H7_SPI_CR1_CSUSP, - spi->base + STM32H7_SPI_CR1); - if (readl_relaxed_poll_timeout_atomic( - spi->base + STM32H7_SPI_SR, - sr, !(sr & STM32H7_SPI_SR_SUSP), - 10, 100000) < 0) - dev_warn(spi->dev, - "Suspend request timeout\n"); - } - } - - if (!spi->cur_usedma && spi->rx_buf && (spi->rx_len > 0)) - stm32h7_spi_read_rxfifo(spi); - if (spi->cur_usedma && spi->dma_tx) dmaengine_terminate_all(spi->dma_tx); if (spi->cur_usedma && spi->dma_rx) -- cgit v1.2.3 From 7ceb0b8a3ceddc36ae4ef1cba6c25a0e28ed65fc Mon Sep 17 00:00:00 2001 From: Alain Volmat Date: Wed, 7 Jul 2021 10:27:06 +0200 Subject: spi: stm32: finalize message either on dma callback or EOT Depending on the usage, it is necessary to perform the finalize message operation either upon receiving the EOT interruption, eiher upon receiving the DMA callback. Indeed, when relying on DMA, even if the SPI EOT IT has been received, it is necessary to wait for the end of the DMA RX transaction before accessing to the data. Signed-off-by: Alain Volmat Link: https://lore.kernel.org/r/1625646426-5826-8-git-send-email-alain.volmat@foss.st.com Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 57 +++++++++++++++++-------------------------------- 1 file changed, 20 insertions(+), 37 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 535f4bebc010..14ca7ea04e47 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -911,7 +911,10 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id) if (sr & STM32H7_SPI_SR_EOT) { if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0))) stm32h7_spi_read_rxfifo(spi); - end = true; + if (!spi->cur_usedma || + (spi->cur_usedma && (spi->cur_comm == SPI_SIMPLEX_TX || + spi->cur_comm == SPI_3WIRE_TX))) + end = true; } if (sr & STM32H7_SPI_SR_TXP) @@ -1019,42 +1022,17 @@ static void stm32f4_spi_dma_tx_cb(void *data) } /** - * stm32f4_spi_dma_rx_cb - dma callback + * stm32_spi_dma_rx_cb - dma callback * @data: pointer to the spi controller data structure * * DMA callback is called when the transfer is complete for DMA RX channel. */ -static void stm32f4_spi_dma_rx_cb(void *data) +static void stm32_spi_dma_rx_cb(void *data) { struct stm32_spi *spi = data; spi_finalize_current_transfer(spi->master); - stm32f4_spi_disable(spi); -} - -/** - * stm32h7_spi_dma_cb - dma callback - * @data: pointer to the spi controller data structure - * - * DMA callback is called when the transfer is complete or when an error - * occurs. If the transfer is complete, EOT flag is raised. - */ -static void stm32h7_spi_dma_cb(void *data) -{ - struct stm32_spi *spi = data; - unsigned long flags; - u32 sr; - - spin_lock_irqsave(&spi->lock, flags); - - sr = readl_relaxed(spi->base + STM32H7_SPI_SR); - - spin_unlock_irqrestore(&spi->lock, flags); - - if (!(sr & STM32H7_SPI_SR_EOT)) - dev_warn(spi->dev, "DMA error (sr=0x%08x)\n", sr); - - /* Now wait for EOT, or SUSP or OVR in case of error */ + spi->cfg->disable(spi); } /** @@ -1220,11 +1198,13 @@ static void stm32f4_spi_transfer_one_dma_start(struct stm32_spi *spi) */ static void stm32h7_spi_transfer_one_dma_start(struct stm32_spi *spi) { - /* Enable the interrupts relative to the end of transfer */ - stm32_spi_set_bits(spi, STM32H7_SPI_IER, STM32H7_SPI_IER_EOTIE | - STM32H7_SPI_IER_TXTFIE | - STM32H7_SPI_IER_OVRIE | - STM32H7_SPI_IER_MODFIE); + uint32_t ier = STM32H7_SPI_IER_OVRIE | STM32H7_SPI_IER_MODFIE; + + /* Enable the interrupts */ + if (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX) + ier |= STM32H7_SPI_IER_EOTIE | STM32H7_SPI_IER_TXTFIE; + + stm32_spi_set_bits(spi, STM32H7_SPI_IER, ier); stm32_spi_enable(spi); @@ -1736,7 +1716,7 @@ static const struct stm32_spi_cfg stm32f4_spi_cfg = { .set_mode = stm32f4_spi_set_mode, .transfer_one_dma_start = stm32f4_spi_transfer_one_dma_start, .dma_tx_cb = stm32f4_spi_dma_tx_cb, - .dma_rx_cb = stm32f4_spi_dma_rx_cb, + .dma_rx_cb = stm32_spi_dma_rx_cb, .transfer_one_irq = stm32f4_spi_transfer_one_irq, .irq_handler_event = stm32f4_spi_irq_event, .irq_handler_thread = stm32f4_spi_irq_thread, @@ -1756,8 +1736,11 @@ static const struct stm32_spi_cfg stm32h7_spi_cfg = { .set_data_idleness = stm32h7_spi_data_idleness, .set_number_of_data = stm32h7_spi_number_of_data, .transfer_one_dma_start = stm32h7_spi_transfer_one_dma_start, - .dma_rx_cb = stm32h7_spi_dma_cb, - .dma_tx_cb = stm32h7_spi_dma_cb, + .dma_rx_cb = stm32_spi_dma_rx_cb, + /* + * dma_tx_cb is not necessary since in case of TX, dma is followed by + * SPI access hence handling is performed within the SPI interrupt + */ .transfer_one_irq = stm32h7_spi_transfer_one_irq, .irq_handler_thread = stm32h7_spi_irq_thread, .baud_rate_div_min = STM32H7_SPI_MBR_DIV_MIN, -- cgit v1.2.3