[PATCH v3] spi: stm32-qspi: Update spi registering

[PATCH v3] spi: stm32-qspi: Update spi registering

[patrice.chotard]

From: Patrice Chotard <patrice.chotard@foss.st.com>

Some device driver need to communicate to qspi device during the remove
process, qspi controller must be functional when spi_unregister_master()
is called.

To ensure this, replace devm_spi_register_master() by spi_register_master()
and spi_unregister_master() is called directly in .remove callback before
stopping the qspi controller.

This issue was put in evidence using kernel v5.11 and later
with a spi-nor which supports the software reset feature introduced
by commit d73ee7534cc5 ("mtd: spi-nor: core: perform a Soft Reset on
shutdown")

Fixes: c530cd1d9d5e ("spi: spi-mem: add stm32 qspi controller")

Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: <stable@vger.kernel.org> # 5.8.x
---

v3: 
  _ Update error path due to devm_spi_alloc_master() usage

v2: 
  _ update commit message
  _ make usage of devm_spi_alloc_master() instead of spi_alloc_master()

 drivers/spi/spi-stm32-qspi.c | 47 +++++++++++++-----------------------
 1 file changed, 17 insertions(+), 30 deletions(-)

diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
index 514337c86d2c..ffdc55f87e82 100644
--- a/drivers/spi/spi-stm32-qspi.c
+++ b/drivers/spi/spi-stm32-qspi.c
@@ -688,7 +688,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
 	struct resource *res;
 	int ret, irq;
 
-	ctrl = spi_alloc_master(dev, sizeof(*qspi));
+	ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
 	if (!ctrl)
 		return -ENOMEM;
 
@@ -697,58 +697,46 @@ static int stm32_qspi_probe(struct platform_device *pdev)
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi");
 	qspi->io_base = devm_ioremap_resource(dev, res);
-	if (IS_ERR(qspi->io_base)) {
-		ret = PTR_ERR(qspi->io_base);
-		goto err_master_put;
-	}
+	if (IS_ERR(qspi->io_base))
+		return PTR_ERR(qspi->io_base);
 
 	qspi->phys_base = res->start;
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm");
 	qspi->mm_base = devm_ioremap_resource(dev, res);
-	if (IS_ERR(qspi->mm_base)) {
-		ret = PTR_ERR(qspi->mm_base);
-		goto err_master_put;
-	}
+	if (IS_ERR(qspi->mm_base))
+		return PTR_ERR(qspi->mm_base);
 
 	qspi->mm_size = resource_size(res);
-	if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ) {
-		ret = -EINVAL;
-		goto err_master_put;
-	}
+	if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ)
+		return -EINVAL;
 
 	irq = platform_get_irq(pdev, 0);
-	if (irq < 0) {
-		ret = irq;
-		goto err_master_put;
-	}
+	if (irq < 0)
+		return irq;
 
 	ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0,
 			       dev_name(dev), qspi);
 	if (ret) {
 		dev_err(dev, "failed to request irq\n");
-		goto err_master_put;
+		return ret;
 	}
 
 	init_completion(&qspi->data_completion);
 	init_completion(&qspi->match_completion);
 
 	qspi->clk = devm_clk_get(dev, NULL);
-	if (IS_ERR(qspi->clk)) {
-		ret = PTR_ERR(qspi->clk);
-		goto err_master_put;
-	}
+	if (IS_ERR(qspi->clk))
+		return PTR_ERR(qspi->clk);
 
 	qspi->clk_rate = clk_get_rate(qspi->clk);
-	if (!qspi->clk_rate) {
-		ret = -EINVAL;
-		goto err_master_put;
-	}
+	if (!qspi->clk_rate)
+		return -EINVAL;
 
 	ret = clk_prepare_enable(qspi->clk);
 	if (ret) {
 		dev_err(dev, "can not enable the clock\n");
-		goto err_master_put;
+		return ret;
 	}
 
 	rstc = devm_reset_control_get_exclusive(dev, NULL);
@@ -784,7 +772,7 @@ static int stm32_qspi_probe(struct platform_device *pdev)
 	pm_runtime_enable(dev);
 	pm_runtime_get_noresume(dev);
 
-	ret = devm_spi_register_master(dev, ctrl);
+	ret = spi_register_master(ctrl);
 	if (ret)
 		goto err_pm_runtime_free;
 
@@ -806,8 +794,6 @@ static int stm32_qspi_probe(struct platform_device *pdev)
 	stm32_qspi_dma_free(qspi);
 err_clk_disable:
 	clk_disable_unprepare(qspi->clk);
-err_master_put:
-	spi_master_put(qspi->ctrl);
 
 	return ret;
 }
@@ -817,6 +803,7 @@ static int stm32_qspi_remove(struct platform_device *pdev)
 	struct stm32_qspi *qspi = platform_get_drvdata(pdev);
 
 	pm_runtime_get_sync(qspi->dev);
+	spi_unregister_master(qspi->ctrl);
 	/* disable qspi */
 	writel_relaxed(0, qspi->io_base + QSPI_CR);
 	stm32_qspi_dma_free(qspi);
-- 
2.17.1

Re: [PATCH v3] spi: stm32-qspi: Update spi registering

[Lukas Wunner]

On Mon, Jan 17, 2022 at 01:17:44PM +0100, patrice.chotard@foss.st.com wrote:
> Some device driver need to communicate to qspi device during the remove
> process, qspi controller must be functional when spi_unregister_master()
> is called.
> 
> To ensure this, replace devm_spi_register_master() by spi_register_master()
> and spi_unregister_master() is called directly in .remove callback before
> stopping the qspi controller.
> 
> This issue was put in evidence using kernel v5.11 and later
> with a spi-nor which supports the software reset feature introduced
> by commit d73ee7534cc5 ("mtd: spi-nor: core: perform a Soft Reset on
> shutdown")
> 
> Fixes: c530cd1d9d5e ("spi: spi-mem: add stm32 qspi controller")
> 
> Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
> Cc: <stable@vger.kernel.org> # 5.8.x

Reviewed-by: Lukas Wunner <lukas@wunner.de>

Thanks!

Lukas

Re: [PATCH v3] spi: stm32-qspi: Update spi registering

[Mark Brown]

On Mon, 17 Jan 2022 13:17:44 +0100, patrice.chotard@foss.st.com wrote:
> From: Patrice Chotard <patrice.chotard@foss.st.com>
> 
> Some device driver need to communicate to qspi device during the remove
> process, qspi controller must be functional when spi_unregister_master()
> is called.
> 
> To ensure this, replace devm_spi_register_master() by spi_register_master()
> and spi_unregister_master() is called directly in .remove callback before
> stopping the qspi controller.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-linus

Thanks!

[1/1] spi: stm32-qspi: Update spi registering
      commit: e4d63473d3110afd170e6e0e48494d3789d26136

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark