spi: stm32-qspi: Add dirmap support

Add stm32_qspi_dirmap_read() and stm32_qspi_dirmap_create()
to get dirmap support.

Update the exec_op callback which doens't allow anymore memory map
access. Memory map access are only available through the dirmap_read
callback.

Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://lore.kernel.org/r/20210419121541.11617-4-patrice.chotard@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Patrice Chotard

drivers/spi/spi-stm32-qspi.c

@@ -331,7 +331,7 @@ static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op)
 {
 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
 	struct stm32_qspi_flash *flash = &qspi->flash[mem->spi->chip_select];
-	u32 ccr, cr, addr_max;
+	u32 ccr, cr;
 	int timeout, err = 0;
 
 	dev_dbg(qspi->dev, "cmd:%#x mode:%d.%d.%d.%d addr:%#llx len:%#x\n",
@@ -343,18 +343,6 @@ static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op)
 	if (err)
 		goto abort;
 
-	addr_max = op->addr.val + op->data.nbytes + 1;
-
-	if (op->data.dir == SPI_MEM_DATA_IN) {
-		if (addr_max < qspi->mm_size &&
-		    op->addr.buswidth)
-			qspi->fmode = CCR_FMODE_MM;
-		else
-			qspi->fmode = CCR_FMODE_INDR;
-	} else {
-		qspi->fmode = CCR_FMODE_INDW;
-	}
-
 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
 	cr &= ~CR_PRESC_MASK & ~CR_FSEL;
 	cr |= FIELD_PREP(CR_PRESC_MASK, flash->presc);
@@ -364,8 +352,6 @@ static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op)
 	if (op->data.nbytes)
 		writel_relaxed(op->data.nbytes - 1,
 			       qspi->io_base + QSPI_DLR);
-	else
-		qspi->fmode = CCR_FMODE_INDW;
 
 	ccr = qspi->fmode;
 	ccr |= FIELD_PREP(CCR_INST_MASK, op->cmd.opcode);
@@ -441,6 +427,11 @@ static int stm32_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
 	}
 
 	mutex_lock(&qspi->lock);
+	if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes)
+		qspi->fmode = CCR_FMODE_INDR;
+	else
+		qspi->fmode = CCR_FMODE_INDW;
+
 	ret = stm32_qspi_send(mem, op);
 	mutex_unlock(&qspi->lock);
 
@@ -450,6 +441,64 @@ static int stm32_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
 	return ret;
 }
 
+static int stm32_qspi_dirmap_create(struct spi_mem_dirmap_desc *desc)
+{
+	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
+
+	if (desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT)
+		return -EOPNOTSUPP;
+
+	/* should never happen, as mm_base == null is an error probe exit condition */
+	if (!qspi->mm_base && desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
+		return -EOPNOTSUPP;
+
+	if (!qspi->mm_size)
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+
+static ssize_t stm32_qspi_dirmap_read(struct spi_mem_dirmap_desc *desc,
+				      u64 offs, size_t len, void *buf)
+{
+	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
+	struct spi_mem_op op;
+	u32 addr_max;
+	int ret;
+
+	ret = pm_runtime_get_sync(qspi->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(qspi->dev);
+		return ret;
+	}
+
+	mutex_lock(&qspi->lock);
+	/* make a local copy of desc op_tmpl and complete dirmap rdesc
+	 * spi_mem_op template with offs, len and *buf in  order to get
+	 * all needed transfer information into struct spi_mem_op
+	 */
+	memcpy(&op, &desc->info.op_tmpl, sizeof(struct spi_mem_op));
+	dev_dbg(qspi->dev, "%s len = 0x%x offs = 0x%llx buf = 0x%p\n", __func__, len, offs, buf);
+
+	op.data.nbytes = len;
+	op.addr.val = desc->info.offset + offs;
+	op.data.buf.in = buf;
+
+	addr_max = op.addr.val + op.data.nbytes + 1;
+	if (addr_max < qspi->mm_size && op.addr.buswidth)
+		qspi->fmode = CCR_FMODE_MM;
+	else
+		qspi->fmode = CCR_FMODE_INDR;
+
+	ret = stm32_qspi_send(desc->mem, &op);
+	mutex_unlock(&qspi->lock);
+
+	pm_runtime_mark_last_busy(qspi->dev);
+	pm_runtime_put_autosuspend(qspi->dev);
+
+	return ret ?: len;
+}
+
 static int stm32_qspi_setup(struct spi_device *spi)
 {
 	struct spi_controller *ctrl = spi->master;
@@ -555,7 +604,9 @@ static void stm32_qspi_dma_free(struct stm32_qspi *qspi)
  * to check supported mode.
  */
 static const struct spi_controller_mem_ops stm32_qspi_mem_ops = {
-	.exec_op = stm32_qspi_exec_op,
+	.exec_op	= stm32_qspi_exec_op,
+	.dirmap_create	= stm32_qspi_dirmap_create,
+	.dirmap_read	= stm32_qspi_dirmap_read,
 };
 
 static int stm32_qspi_probe(struct platform_device *pdev)