Merge series "spi: stm32: various driver fixes" from Alain Volmat <al…

…ain.volmat@st.com>:

This serie is a reduced version of the serie
[spi: stm32: various driver enhancements] previously sent.

Alain Volmat (1):
  spi: stm32: always perform registers configuration prior to transfer

Amelie Delaunay (3):
  spi: stm32: fix fifo threshold level in case of short transfer
  spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
  spi: stm32: fixes suspend/resume management

Antonio Borneo (1):
  spi: stm32h7: fix race condition at end of transfer

 drivers/spi/spi-stm32.c | 98 ++++++++++++++++++++++++++++++-------------------
 1 file changed, 61 insertions(+), 37 deletions(-)

--
v2: fix conditional statement within [spi: stm32: fix fifo threshold level in case of short transfer]

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drivers/spi/spi-stm32.c

@@ -13,6 +13,7 @@
 #include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>
 #include <linux/spi/spi.h>
@@ -441,7 +442,8 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
 {
 	u32 div, mbrdiv;
 
-	div = DIV_ROUND_UP(spi->clk_rate, speed_hz);
+	/* Ensure spi->clk_rate is even */
+	div = DIV_ROUND_UP(spi->clk_rate & ~0x1, speed_hz);
 
 	/*
 	 * SPI framework set xfer->speed_hz to master->max_speed_hz if
@@ -467,27 +469,37 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
 /**
  * stm32h7_spi_prepare_fthlv - Determine FIFO threshold level
  * @spi: pointer to the spi controller data structure
+ * @xfer_len: length of the message to be transferred
  */
-static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi)
+static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi, u32 xfer_len)
 {
-	u32 fthlv, half_fifo;
+	u32 fthlv, half_fifo, packet;
 
 	/* data packet should not exceed 1/2 of fifo space */
 	half_fifo = (spi->fifo_size / 2);
 
+	/* data_packet should not exceed transfer length */
+	if (half_fifo > xfer_len)
+		packet = xfer_len;
+	else
+		packet = half_fifo;
+
 	if (spi->cur_bpw <= 8)
-		fthlv = half_fifo;
+		fthlv = packet;
 	else if (spi->cur_bpw <= 16)
-		fthlv = half_fifo / 2;
+		fthlv = packet / 2;
 	else
-		fthlv = half_fifo / 4;
+		fthlv = packet / 4;
 
 	/* align packet size with data registers access */
 	if (spi->cur_bpw > 8)
 		fthlv -= (fthlv % 2); /* multiple of 2 */
 	else
 		fthlv -= (fthlv % 4); /* multiple of 4 */
 
+	if (!fthlv)
+		fthlv = 1;
+
 	return fthlv;
 }
 
@@ -971,8 +983,8 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
 	spin_unlock_irqrestore(&spi->lock, flags);
 
 	if (end) {
-		spi_finalize_current_transfer(master);
 		stm32h7_spi_disable(spi);
+		spi_finalize_current_transfer(master);
 	}
 
 	return IRQ_HANDLED;
@@ -1393,7 +1405,7 @@ static void stm32h7_spi_set_bpw(struct stm32_spi *spi)
 	cfg1_setb |= (bpw << STM32H7_SPI_CFG1_DSIZE_SHIFT) &
 		     STM32H7_SPI_CFG1_DSIZE;
 
-	spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi);
+	spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi, spi->cur_xferlen);
 	fthlv = spi->cur_fthlv - 1;
 
 	cfg1_clrb |= STM32H7_SPI_CFG1_FTHLV;
@@ -1585,39 +1597,33 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
 	unsigned long flags;
 	unsigned int comm_type;
 	int nb_words, ret = 0;
+	int mbr;
 
 	spin_lock_irqsave(&spi->lock, flags);
 
-	if (spi->cur_bpw != transfer->bits_per_word) {
-		spi->cur_bpw = transfer->bits_per_word;
-		spi->cfg->set_bpw(spi);
-	}
-
-	if (spi->cur_speed != transfer->speed_hz) {
-		int mbr;
+	spi->cur_xferlen = transfer->len;
 
-		/* Update spi->cur_speed with real clock speed */
-		mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
-					    spi->cfg->baud_rate_div_min,
-					    spi->cfg->baud_rate_div_max);
-		if (mbr < 0) {
-			ret = mbr;
-			goto out;
-		}
+	spi->cur_bpw = transfer->bits_per_word;
+	spi->cfg->set_bpw(spi);
 
-		transfer->speed_hz = spi->cur_speed;
-		stm32_spi_set_mbr(spi, mbr);
+	/* Update spi->cur_speed with real clock speed */
+	mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
+				    spi->cfg->baud_rate_div_min,
+				    spi->cfg->baud_rate_div_max);
+	if (mbr < 0) {
+		ret = mbr;
+		goto out;
 	}
 
+	transfer->speed_hz = spi->cur_speed;
+	stm32_spi_set_mbr(spi, mbr);
+
 	comm_type = stm32_spi_communication_type(spi_dev, transfer);
-	if (spi->cur_comm != comm_type) {
-		ret = spi->cfg->set_mode(spi, comm_type);
+	ret = spi->cfg->set_mode(spi, comm_type);
+	if (ret < 0)
+		goto out;
 
-		if (ret < 0)
-			goto out;
-
-		spi->cur_comm = comm_type;
-	}
+	spi->cur_comm = comm_type;
 
 	if (spi->cfg->set_data_idleness)
 		spi->cfg->set_data_idleness(spi, transfer->len);
@@ -1635,8 +1641,6 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
 			goto out;
 	}
 
-	spi->cur_xferlen = transfer->len;
-
 	dev_dbg(spi->dev, "transfer communication mode set to %d\n",
 		spi->cur_comm);
 	dev_dbg(spi->dev,
@@ -1996,6 +2000,8 @@ static int stm32_spi_remove(struct platform_device *pdev)
 
 	pm_runtime_disable(&pdev->dev);
 
+	pinctrl_pm_select_sleep_state(&pdev->dev);
+
 	return 0;
 }
 
@@ -2007,13 +2013,18 @@ static int stm32_spi_runtime_suspend(struct device *dev)
 
 	clk_disable_unprepare(spi->clk);
 
-	return 0;
+	return pinctrl_pm_select_sleep_state(dev);
 }
 
 static int stm32_spi_runtime_resume(struct device *dev)
 {
 	struct spi_master *master = dev_get_drvdata(dev);
 	struct stm32_spi *spi = spi_master_get_devdata(master);
+	int ret;
+
+	ret = pinctrl_pm_select_default_state(dev);
+	if (ret)
+		return ret;
 
 	return clk_prepare_enable(spi->clk);
 }
@@ -2043,10 +2054,23 @@ static int stm32_spi_resume(struct device *dev)
 		return ret;
 
 	ret = spi_master_resume(master);
-	if (ret)
+	if (ret) {
 		clk_disable_unprepare(spi->clk);
+		return ret;
+	}
 
-	return ret;
+	ret = pm_runtime_get_sync(dev);
+	if (ret) {
+		dev_err(dev, "Unable to power device:%d\n", ret);
+		return ret;
+	}
+
+	spi->cfg->config(spi);
+
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
+	return 0;
 }
 #endif